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How are hybrid inverters used in solar projects?

This paper proposes a new configuration of a single-phase hybrid inverter with an integrated battery energy storage, which is suitable for residential households to maximize local consumption of solar energy and thus reduce dependency on grid support. The hybrid inverter is called Direct Storage Hybrid (DSH) Inverter. A transformer-less topology such as HERIC, operating at low frequency to generate a three-level rectangular output voltage, is adopted to connect a photovoltaic (PV) panel to the load and/or the grid. A series active filter is employed to compensate the high harmonic components from the rectangular voltage and provide a sinusoidal voltage. A bidirectional dc/dc converter connects the battery to the PV panel to control the battery state of charge (SoC) and optimize the PV panel operation during both off-grid and grid-connected modes. The DSH inverter can let the battery bypass the dc/dc converter and connect directly to the inverter stage, leading to a significant improvement in throughput efficiency in battery utilization. This paper discusses the operation and loss analysis of the DSH inverter in off-grid mode.

This paper is designed in such a way that it overcomes this limitation by the use of solar energy. NA hybrid inverter lv with Solar Battery Charging System consists of an inverter powered by a 12V Battery. This inverter generates up to 230V AC with the help of driver circuitry and a heavy load transformer. This battery gets charged from two sources, first being the mains power supply itself and second from the solar power. If the mains power supply is available, then the relay switches to main power supply for supplying the load. This power supply also charges the battery for using it as back up the next time when there is a power outage. The use of solar panel to charge the battery gives an additional advantage of surplus power in case the power outage of mains is prolonging. Thus this inverter can last for longer duration’s and provide uninterrupted power supply to the user.

Hybrid inverters are commonly used in the developing world, but they are starting to make their way into daily use in certain areas of the U.S due to their ability to stabilize energy availability.

A solar inverter’s main job is to convert DC power generated from the array into usable AC power. Hybrid inverters go a step further and work with batteries to store excess power as well. This type of system solves issues renewable energy variability and unreliable grid structures.

“Inverters for grid-tied applications can only provide power based on what the array can immediately generate from the sun,” explained Bryan Whitton, product manager at Darfon. “Hybrid inverters can store power in batteries and then drawn upon it as needed for energy stabilization.”

Hybrid inverters can vary in size, performance and features. But Mara White, product manager for OutBack Power, said most models usually operate bi-directionally, meaning they can convert DC power from modules to usable AC power and then convert stored AC from the batteries to power loads when needed. “Hybrids can also remain grid-connected and use a mix of renewable and non-renewable energy to charge batteries and offset loads,” White added.

Some contractors have used hybrid inverters in the residential, remote home applications for the past decade or two. But Allan Gregg, VP of applications engineering at GreatWall—which manufactures Satcon inverters—said the range of applications has expanded over the past few years to include large capacity microgrids as well as grid-connected systems.

Historically, hybrid inverters have been used more frequently in developing countries that do not have access to a reliable power grid.

“In North America and Europe, hybrid inverter-based systems are usually elective,” White explained. “Users choose to use them for storing energy for self-consumption or provide back-up power during emergencies. But in the developing world, hybrids are more of a necessity to compensate for weak or intermittent grids or a lack of grid electricity all together. Microgrids in places such as India, Asia and Africa are also driving na hybrid inverter hv adaptation.”

Still, Whitton said hybrid models are beginning to be used on a more daily basis in areas of the U.S. where the grid is unpredictable, such as Hawaii, or in states where net-metering has been widely supported. “Applications with less than ideal solar characteristic are also good for hybrid-based systems because they can store power and redistribute it during peak times, improving payback,” he added. “Basically, if the site has the potential for losing the grid frequently, you should consider a hybrid for off-grid operation.”

Having the flexibility of a hybrid system can add initial cost to a project, though experts say this can be offset by the ability to self-consume all of one’s available PV electricity.

There are also important design considerations when using hybrid inverters. For example, Gregg warned that the battery bank voltage should be compatible with the DC input requirements of the inverter, and there should be enough solar capacity to supply the load as well as charge the batteries.

Wiring can also be more complex when using hybrid inverters, especially when panels are dedicated for critical backed-up loads. “And as with any device that does several jobs at once, a hybrid inverter is usually slightly less efficient,” White added, “although, improvements in other balance-of-system components can compensate for that slight loss easily.”

There are also specific electrical safety issues with any type of energy storage, so White recommended getting specialized training in energy storage techniques and design. “Most available training is focused on simple grid-tied systems because they have been the majority of U.S. solar installations until now,” she said. “But with incentives changing and the surge in energy storage interest and applications, it’s important to get ahead of the curve and get advanced training quickly.”

Andrew McCalla of Austin, Texas-based Meridian Solar, a Solar Power World top contractor, said he commonly used hybrids in the mid to late ’90s when the now standard grid-tie inverter sector was just a glimmer. “I can imagine that, when regulatory hurdles are fabricated to limit the consumer and societal benefits of bi-directional power flow from distributed generation, these battery-based platforms will become far more common. What is old is new again!”

Another segment of hybrid inverters includes inverters that can use two energy sources. For example, Ginlong offers a PV / wind lv battery hybrid inverter that has inputs for both sources, instead of having to use two inverters. In much of the United States, wind speeds are low in the summer when the sun shines brightest and longest. The wind is strong in the winter when less sunlight is available. Therefore, because the peak operating times for wind and solar systems occur at different times of the day and year, such hybrid systems have the potential to produce power when it’s needed, and reach a higher return on investment.

When you first consider getting solar or battery storage on your home or business, one of the first things you will discover is that you will require an inverter and that there are many different types of inverters available. This article is designed to provide an introduction to the different kinds of inverters available and help you to understand which one will suit your installation. So what does an inverter do? Simply put an Inverter converts DC power to AC power. Solar panels produce DC power and batteries store DC, however most of our appliances run on AC power, as does the electricity grid. This is why all solar systems and battery storage systems need an inverter however there are several different types of inverters depending on whether or not energy storage batteries are required.

On-grid solar installations are the most common and most affordable type of system available at present. These systems use a simple solar inverter, which convert the DC power from your solar panels into AC power which can be fed directly into the grid, or used in your home appliances.

Off-grid and hybrid systems are much more complex because they involve both solar panels as well as battery storage. Multiple inverters are often required in these installations such as a solar inverter and sophisticated battery inverter/charger to manage both grid connection and the charging and discharging of the batteries. These advanced inverter/chargers are known as interactive or multi-mode inverters. However, in recent years a new type of inverter has become available which integrates solar and battery inverter technology into what is known as an all-in-one hv battery hybrid inverter.

A micro-inverter is a very small inverter that is attached to the back of a solar panel. A micro-inverter only converts the power of one or two solar panels to AC so generally many microinverters are required in a single system. Micro-inverters have several advantages over string inverters including performance, safety and monitoring, however the upfront cost can be significantly greater. For more details about micro-inverters, check out our micro-inverters article.

String solar inverters come in single phase and three phase versions although most residential homes in the US and Australia use single phase power, while many homes in Europe use 3-phase power, also all businesses and factories will have three phase power. As a general rule most String solar inverters between 1-6kW are single phase and greater than 6kW are usually three phase.

As home energy storage systems have surged in popularity a new kind of advanced Inverter has emerged known as an hybrid inverter. Hybrid inverters combines a solar inverter and battery inverter/charger into one simple unit. These inverters are a very economical way to enable what is known as ‘self-use’ or 'load shifting' of energy. Allowing you to store solar or off-peak energy in a battery to be used during peak times. Although it is important to know that some all-in-one inverters cannot function during a power outage such as when there is a blackout. They can also have limited functionality and monitoring capabilities.The traditional off-grid solar system uses a simple battery inverter that converters DC power from a battery bank to AC power to supply your home or appliances, these systems need separate battery chargers and regulators. There are more advanced versions of these battery inverters with built in chargers known as inverter/chargers. In recent years very advanced inverters have become available which are inverter/chargers with in-built generator control systems, advanced monitoring capabilities and other features, these are known as interactive or multi-mode inverters. They are typically used in conjunction with a solar inverter to create what is known as an AC coupled system. You can learn more about these and other hybrid inverter types here.

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Making process control valve choices

Today’s process control valves offer an ever wider range of features and benefits for industries that require precise control over fluids, steam and other gases. With so many control valves to choose from it is important to establish the features that will deliver the most cost-effective design for a particular application.

Control valves are used to manage the flow rate of a liquid or a gas and in-turn control the temperature, pressure or liquid level within a process. As such, they are defined by the way in which they operate to control flow and include globe valves, angle seat, diaphragm, quarter-turn, knife and needle valves, to name a few. In most cases the valve bodies are made from metal; either brass, forged steel or in hygienic applications 316 stainless steel.

Actuators will use an on-board system to measure the position of the valve with varying degrees of accuracy, depending on the application. A contactless, digital encoder can place the valve in any of a thousand positions, making it very accurate, while more rudimentary measurements can be applied to less sensitive designs.

One of the main areas of debate when specifying globe control valve is determining the size of the valve required. Often process engineers will know the pipe diameter used in an application and it is tempting to take that as the control valve’s defining characteristic. Of greater importance are the flow conditions within the system as these will dictate the size of the orifice within the control valve. The pressure either side of the valve and the expected flow rate are essential pieces of information when deciding on the valve design.

Inside the valve body, the actuator design is often either a piston or a diaphragm design. The piston design typically offers a smaller, more compact valve which is also lighter and easier to handle than the diaphragm designs. Actuators are usually made from stainless steel or polyphenolsulpide (PPS), which is a chemically-resistant plastic. The actuator is topped off by the control head or positioner.

Older, pneumatically operated positioners had a flapper/nozzle arrangement and operated on 3-15psi, so no matter what the state of the valve, open closed or somewhere in between, the system was always expelling some compressed air to the atmosphere.

Compressed air is an expensive commodity, requiring considerable energy to generate and when a manufacturing line is equipped with multiple process control valves all venting to the atmosphere, this can equate to a considerable waste of energy. It is important to not only establish the most appropriate valve design, but also a cost-effective solution that takes account of annual running costs.

Modern, digital, electro-pneumatic valves that use micro-solenoid valves to control the air in and out of the actuator have introduced significant improvements for operators. This design means that while the valve is fully open, fully closed or in a steady state, it is not consuming any air. This, and many other engineering improvements, have made substantial advances in both economy and precision.

Flexible designs

Valve seats can be interchangeable within a standard valve body, which allows the valve to fit existing pipework and the valve seat to the sized to the application more accurately. In some cases, this can be achieved after the valve has been installed, which would enable a process change to be accommodated without replacing the complete valve assembly.

Selecting the most appropriate seal materials is also an important step to ensure reliable operation; Steam processes would normally use metal-to-metal seals, whereas a process that included a sterilization stage may require chemically resistant seals.

Setting up and installing a new valve is now comparatively easy and much less time-consuming. In-built calibration procedures should be able perform the initial setup procedures automatically, measuring the air required to open and close the valve, the resistance of the piston seals on the valve stem and the response time of the valve itself.

Improving safety

Control valves should be specified so they operate in the 40-85% range so if the valve is commanded to a 10% setting, it can detect if something has potentially gone wrong with the control system and the best course of action is to close the valve completely. If the valve is commanded to a position of 10% or less this can cause very high fluid or gas velocities, which have damaging effects on the system and cause considerable noise and damage to the valve itself.

Modern control functionality can offer a solution that acts as a safety device to prevent damage to the process pipework and components. By building in a fail-safe mechanism, any valve position setting below a pre-set threshold will result in the valve closing completely, preventing damage to the surrounding system.

Control inputs can also include safety circuits to ensure safe operating conditions within the process equipment. For example, if an access panel on a vessel containing steam is opened, an interlock switch will open and the valve controlling the steam supply to the vessel can be automatically closed, helping mitigate any risks.

Improving reliability

Many process control environments offer less than ideal conditions for long-term reliability. Moisture-laden atmospheres, corrosive chemicals and regular wash-downs all have the capacity to shorten the service life of a process Self regulating control valve. One of the potential weaknesses of the actuator is the spring chamber where atmospheric air is drawn in each time the valve operates.

One solution is to use clean, instrument air to replenish the spring chamber, preventing any contamination from entering. This offers a defense against the ingress of airborne contaminants by diverting a small amount of clean control air into the control head, maintaining a slight positive pressure, thus achieving a simple, innovative solution. This prevents corrosion of the internal elements and can make a significant improvement to reliability and longevity in certain operating conditions.

While choosing the most appropriate process control valve can be a complex task, it is often best achieved with the assistance of expert knowledge. Working directly with manufacturers or knowledgeable distributors enables process control systems to be optimized for long-term reliability as well as precision and efficiency.

Damien Moran is field segment manager, Hygienic – Pharmaceutical at Bürkert. This article originally appeared on the Control Engineering Europe website. Edited by Chris Vavra, associate editor, Control Engineering, CFE Media and technology, [email protected].

Control valves are generally present whenever fluid flow regulation is required. The three way and angle control valve reliability is critical to the control quality and safety of a plant. An improved dynamic and static valve behaviour would have a major impact on the process output. In order to assess the dynamic performance of the control valve, a computer model of an electro-hydraulic control valve is developed. And the control valve characteristics are investigated through the use of mathematical simulations of the control valve dynamic performance. The results show that the electro-hydraulic driven control valve, which is developed to regulate the mixed-gas pressure in combined cycle power plant, can meet the challenge of the gas turbine.

Control valves play important roles in the control of the mixed-gas pressure in the combined cycle power plants (CCPP). In order to clarify the influence of coupling between the structure and the fluid system at the control valve, the coupling mechanism was presented, and the numerical investigations were carried out. At the same operating condition in which the pressure oscillation amplitude is greater when considering the coupling, the low-order natural frequencies of the plug assembly of the valve decrease obviously when considering the fluid-structure coupling action. The low-order natural frequencies at 25% valve opening, 50% valve opening, and 75% valve opening are reduced by 11.1%, 7.0%, and 3.8%, respectively. The results help understand the processes that occur in the valve flow path leading to the pressure control instability observed in the control valve in the CCPP.

1. Introduction

The steel mills generate vast amounts of blast furnace gas (BFG) and coke-oven gas (COG) in the production. In order to reduce the environmental pollution, some steel mills mix BFG with COG and build combined cycle power plants (CCPP) to make use of the gas [1]. For the normal operation of CCPP, the pressure of mixed gas delivered to the gas turbine should be kept in a steady range.

In CCPP, control valves play important roles in the control of the mixed-gas pressure. The signal of mixed-gas pressure measured using the pressure meter is compared to the signal of the desired pressure by the controller. The controller output accordingly adjusts the opening/closing actuator of the control valve in order to maintain the actual pressure close to the desired pressure. The opening of the control valve depends on the flow forces and the driving forces of the control-valve actuator, while the flow forces and the driving forces are affected by the valve opening. Therefore, there is strong coupling interaction between the fluid and the control valve structure.

According to Morita et al. (2007) and Yonezawa et al. (2008), the typical flow pattern around the Knife Gate Valve is transonic [2, 3]. When pressure fluctuations occur, large static and dynamic fluid forces will act on the valves. Consequently, problematic phenomena, such as valve vibrations and loud noises, can occur, with the worst cases resulting in damage of the valve plug and seal [4]. In order to understand the underlying physics of flow-induced vibrations in a steam control valve head, experimental investigations described by Yonezawa et al. (2012) are carried out. Misra et al. (2002) reported that the self-excited vibration of a piping system occurs due to the coincidence of water hammer, acoustic feedback in the downstream water piping, high acoustic resistance at the control valve, and negative hydraulic stiffness at the control valve [5]. Araki et al. (1981) reported that the steam control-valve head oscillation mechanism was forced vibration, while self-excited vibration was not observed [6].

Those studies cited previously are mainly aimed at the modeling of the self-excited vibration, the analysis of vibration parameters stability, and so on [7–11]. Whereas, the studies on the influence of nonlinear fluid-structure coupling of control valve on the valve control characteristics, such as the pressure regulation feature, are still very limited [12–17]. In the CCPP, the valve control characteristics affected by the fluid-structure coupling are particularly important for the stability of the mixed-gas pressure control. It has not been uncommon to see that the instability of the mixed-gas pressure causes a severe disturbance or even an emergency shutdown of the whole plant, and the handling of such an emergency often becomes a source of new problems and confusion. In this paper, numerical investigations are carried out to clarify the influence of fluid-structure coupling of control valve on not only the flow field but also the gas pressure regulation and the natural frequency changes of the control valve. This study helps understand the processes that occur in the valve flow path leading to the mixed-gas pressure pulsations, which is valuable for the pressure stability control of the mixed gas in the CCPP.

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8 Benefits of Spin Class That’ll Convince You to Finally Try One

One of the many reasons we love cycling is that it allows us to get outside and explore. But with winter at our doorstep, sometimes the weather is just plain awful or there’s just not enough time in the day. The next best option? A Spin class, of course.

Most studios offer a variety of class options—some as short as 20 minutes or as long as 90 minutes—so you’re always able to fit a workout into your schedule. Nowadays, there are even at-home magnetic spinning bike available that stream classes directly into your living room from companies like Peloton, NordicTrack, and Technogym. Peloton’s beginner-friendly classes, for example, teach participants the correct form and technique that will translate to every other level.

Plus, the work you do in a class—whether that’s at home or in a gym—complements your on-the-road training perfectly, according to Peloton instructor Jess King. “It’s an opportunity for you to play around with your training—there’s something for you to hear, learn, and experience that you can take with you back on the road. So why not dip into both worlds?” she says.

Spinning is one of those things that seems a bit intimidating if you’ve never done it before. But as long as you have access to a gym or a bike, you can take classes that range from beginner to expert, King says, each of which helps build the main muscle groups used for cycling and your cardiovascular system.

“We have this unique opportunity to create something for everyone,” King says. But most studios and instructors offer a variety of options that will suit your needs or experience level.

And if you’ve already got the stamina to climb hills and ride long outside, you’re that much more ready to conquer a Spin class. Both studios and at-home options offer longer, more advanced classes as well.

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It goes without saying that taking a Spin class is not the same as riding outside. While you can still experience similar terrain (hills and flat ground), King says in-studio and virtual Spin classes can feel more like a party than a workout.

“There’s music from all different decades—from classic rock to EDM—and we use interval training, tabata training, and heart rate training, so it’s still a great workout,” she says about Peloton, though competitors offer a similar experience.

A lot of times when you’re out on the road, it’s just you and the voice that’s in your head. That can be a good thing when you want to escape to nature and clear your mind, but it can be a bad thing when the voice is telling you to turn home. Being in a class setting changes things up—especially when you have the motivation of an instructor cheering you on. (Because let’s be real, there are times when you just really don’t want to do that interval workout on your own.)

“Spin gives you a new perspective on how to ride, breathe, and think about your body,” King says.

When you take an indoor cycling class, everyone from the instructor to the other participants are there to encourage and support you.

“Everyone is rooting for you—you’re not alone in this experience,” King says. “We’re using the bike as the medium for that connection and energy.”

And Charlee Atkins, C.S.C.S., former master instructor at SoulCycle and founder of Le Sweat, agrees. “[Everyone] is very supportive—they hold each other accountable and celebrate each other’s wins and losses,” she says. “They oftentimes can become an ‘extended family’ of sorts.”

It can be really tough to be out on your indoor cycle spinning bike alone, struggling to finish a particularly challenging ride. Sometimes your first instinct is to give up. But when there are other people around you, it makes you want to keep going and prove you can finish what you started. That’s exactly what taking a Spin class does. And that mindset can and will benefit you on the road, too.

If you’ve already found a great community of riders outdoors, indoor classes offer the same camaraderie and accountability, just in a different setting.

4. It’s a great total-body workout.

Not only does a Spin class benefit your muscles—everything from your legs to your core—but it’s also a great low-impact cardiovascular workout, which improves your blood flow, increases your stamina, boosts your mood, and prevents against chronic issues such as high blood pressure, heart disease, stroke, and diabetes, according to Mayo Clinic.

And because of this intense cardio workout, you’ll burn a ton of calories, too. While King says the average is about 400 to 600 calories per class, she’s seen some riders burn more if they’re going particularly hard and long.

Some indoor cycling classes even incorporate the use of hand weights to “promote upper-body work, since cycling is a predominantly lower-body workout,” Atkins adds. So in one 45-minute session, you can challenge your upper body, lower body, and core.

5. It’s convenient.

Riding outside can take a couple of hours to complete, and most people don’t have that kind of time during the week. So taking an indoor cycling class either at home, at a gym, or in a studio is a great option for when your schedule is packed, and you only have an hour or less to work out.

But don’t worry—exercising for a shorter amount of time doesn’t mean you aren’t reaping the same benefits as a longer workout. Many classes feature high-intensity intervals which help you build increased cardiovascular and muscular fitness in less time than a longer but steady-state ride out on the road.

6. It’s low impact.

Indoor cycling won’t beat up your joints like other forms of cardio such as running. “It’s great for people who are coming back from an injury,” says Atkins, because your hips, knees, and ankles won’t take all the impact. This makes it a great choice for those who aren’t yet functioning at 100 percent after getting hurt, older adults looking for a way to stay active without putting extra pressure on their joints, or those who suffer from arthritis.

7. You can make it your own.

Out on the roads, you can’t lower the grade of a mountain if you’re not up for climbing it that day. But the beauty of a Spin class is that you can customize it to your own needs. The Spin instructor is there to guide you, but you can always modify the workout.

For example, you don’t have to stay on the bike during the upper-body workout portion of the class if you feel safer on solid ground. You can also go slower if you need to—you don’t have to worry about getting dropped. And if the class motivates you to push yourself even harder, maybe try racing your friend next to you. Everyone in class is there to work out to the best of their ability while enjoying the motivational vibes of the group. So whatever you’re feeling, go ahead and do your thing.

8. It gives your bike a break.

Switching it up with some Spin classes will also give your commercial spinning bike a break from the elements, not just your body. Rain, dirt, and snow will take their toll on your components over time. Replacing just some of your workouts with Spin classes will give you the opportunity to buy and install new parts, or time to take your bike into the shop for a tuneup.

Spinning might look about the same as outdoor cycling or riding a stationary bike, but in many ways, it’s a far more intense workout—and one of the easiest to overdo.

First, there aren’t many (if any) breaks in spin class. “When you’re biking outside, you have to be aware of road dangers like water and cars, so you have to slow down at times,” says Dr. Maureen Brogan, an assistant professor of medicine at New York Medical College who has conducted research into spinning. Especially if you’re a novice road rider, it’s going to take some time before you’re comfortable enough on two wheels to really push yourself hard for long distances. That’s not the case on a spinning bike, where newbies can hop on and ride hard from the start.

Popular spinning studios like Flywheel and SoulCycle have their riders clip their feet into the stationary bikes. As long as the wheels turn, legs keep pumping. Combine this always-working aspect with the thumping music, enthusiastic instructors and energetic group atmosphere of most spinning studios, and it’s easy to get intense exercise and burn calories by the bucketful.

“The muscles you use on spinning bikes, the gluteus maximus and the quadriceps, are some of the largest in your body, so you’re using a lot of energy,” Brogan says—600 calories an hour, and sometimes more.

This puts spinning near the top of the list when it comes to high-intensity workouts. A study from Sweden found that one hour of spinning was enough to trigger the release of blood chemicals associated with heart stress or changes. While that may sound like a bad thing, these blood chemicals—or biomarkers—signal the heart is getting a good workout. “These kinds of findings have also been seen with prolonged exertion such as marathons,” says study author Dr. Smita Dutta Roy of Sahlgrenska University Hospital in Sweden. While more research is needed to tease out the risks or benefits associated with exercise of this intensity, she says that some of the biomarker shifts her team observed could lead to blood vessel repair and renewal.

It can also help improve body composition, decrease fat mass and lower blood pressure and cholesterol, says Jinger Gottschall, an associate professor of kinesiology at Penn State University. Some of her research has shown that high-intensity spinning can increase fitness levels even in trained athletes. “In every study we’ve done, we’ve seen increases in heart and lung capacity,” she says. She calls spinning “the optimal cardio workout,” and says you can get all the intensity of a treadmill or stair-climber without the impact.

The low-impact nature of spinning makes it great exercise for older adults or people recovering from orthopedic injuries, she adds. “Because you can adjust the resistance and moderate the pace and intensity of your ride, it opens the door for many people to participate,” she says.

But it’s also easy for people who are new to spinning to overexert themselves. “If you’re not used to vigorous exercise, or to exercising the large lower-body muscles involved in spinning, you can overdo it,” Brogan says. She’s a kidney expert by training, and some of her research has linked spinning to rhabdomyolysis, a condition in which muscles break down to the point that they release a protein that can poison the kidneys. “People have swollen legs or trouble walking, and sometimes they take aspirin or NSAIDs for the muscle pain, which is the last thing they should do because those can also damage the kidneys,” she says. Problems like this can set in a day or two after spin class, she says.

While overexertion is possible with any form of exercise, she says the risks during spinning may be higher—especially when you consider that some spinners lose up to a liter of water during an hour-long session.

Even for trained athletes, there’s some evidence that spinning too often may lead to trouble. A study in the Journal of Strength and Conditioning Research concluded that spinning may push some people past the threshold at which the exercise is beneficial. “If indoor cycling were used as an everyday training activity, it is possible that the overall intensity would be too high and possibly contribute to developing nonfunctional overreaching,” the authors of that study write. (“Nonfunctional overreaching” is sports science lingo for a workout that’s so strenuous it leads to fatigue and performance declines, rather than fitness improvements.)

Overall, spinning is exceptional exercise. But if you’re new to it, you need to ease in and give your muscles time to adapt to its intensity. Even if you’re an experienced athlete, pushing yourself to your limit the first or second time you get on a spinning bike may be risky, Brogan says. Even once you’ve found your spinning legs, daily sessions may still be overkill.

But if you’re looking for a high-intensity workout a few days a week—and especially if running or other forms of vigorous aerobic exercise hurt your joints—spinning may be the ideal way to keep your heart and body in shape.

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Top Industrial Belt Conveyor Issues

The advent of troughed belt conveyors fundamentally changed industrial processing, increasing efficiencies, reducing labor requirements, improving safety, and streamlining production. These flexible devices have become the standard for moving product and material around a facility and are found in every industry imaginable.

While belt conveyors provide a reliable, efficient bulk handling solution, they can experience occasional problems. And when issues arise, they can wreak havoc on a production line. Below are some of the most commonly seen issues when working with belt conveyors, including what causes these problems and how to prevent them.

Note: This is not a comprehensive list and does not substitute for the expertise of a professional. Always consult your original equipment manufacturer or manual to ensure all necessary safety, maintenance, and troubleshooting guidelines are followed. Maintenance and storage procedures should always be carried out by a trained professional. FEECO does not make any representations or warranties (implied or otherwise) regarding the accuracy and completeness of this guide and shall in no event be liable for any loss of profit or any commercial damage, including but not limited to special, incidental, consequential, or other damage.

Carryback is the material that remains on the belt after discharge and is perhaps the most common struggle among conveyor pulley. Typically all conveyors experience carryback to some extent, but given its potential for serious consequences, keeping it to a minimum is essential.

WHY CARRYBACK IS AN ISSUE

Carryback creates a messy and potentially hazardous work environment, as it gets into the undercarriage and surrounding area of the conveyor. This can cause outages and increase the time devoted to cleaning and maintenance.

Not only does carryback create a mess, but material allowed to build up on rollers, idlers, and pulleys degrades these components, causing excessive wear. Further, a buildup of carryback can also cause belt tracking issues, potentially wearing and damaging the belt.

WHAT CAUSES CARRYBACK

Carryback is largely a result of the conveyed material’s characteristics and propensity for sticking. In general, a material with a higher moisture content is more likely to stick to the belt. Similarly, carryback can be more of a problem in humid environments where hygroscopic materials pull moisture from the air, increasing the likelihood of sticking.

Sticking can also occur when condensation is produced as a result of extreme temperature differences between the material and the belt.

HOW TO PREVENT CARRYBACK

The best way to prevent carryback is to utilize one or more belt cleaners. Belt cleaners can be installed at both the head and tail pulley and serve to ride against the conveyor belt, dislodging any material that may be adhered to the belt. These devices substantially reduce buildup on the belt, and depending on the level of carryback, several options may be appropriate. Common options include a self-cleaning tail pulley, return side belt plow (v-plow), and dual belt cleaners.

Routine cleaning should also be prioritized as part of a conveyor head pulley maintenance program in order to minimize any remaining buildup on components.

CONVEYOR BELT MISTRACKING

Tracking, or training, refers to the way in which the belt rides on the rollers. Conveyor belts should always track centrally. Mistracking occurs when the conveyor rubber belt rides unevenly on rollers, favoring one side over the other.

Like carryback, mistracking can cause several issues in a conveyor system. This includes uneven belt wear, belt damage resulting from catching or rubbing on surrounding infrastructure, material spillage, warped belting or belts that are not square, and more.

Mistracking is also recognized as a safety violation by the US Department of Labor’s Mine Safety and Health Administration (MSHA). When a belt is not tracking properly, areas that are normally safe can become pinch points, presenting a hazard to workers. Mistracking can also cause material to fall off of the conveyor, falling on to workers and equipment, or creating piles that present a safety risk.

WHAT CAUSES MISTRACKING

Since conveyor bend pulley are carefully balanced, any number of factors may be the source of mistracking, making it difficult to identify the origin of the problem. Potential causes of mistracking include improper idler spacing, seized or worn rollers, a misaligned frame, material buildup on any part of the conveyor, excessive belt tensioning, and a worn or damaged belt, to name a few.

HOW TO PREVENT MISTRACKING

The range of possible mistracking causes make a blanket solution to prevention impossible. There are, however, measures that can help to reduce the potential for this issue to occur.

Conveyors can fall out of perfect alignment through normal wear and tear. As a result, routinely inspecting alignment of the conveyor structure and its many components helps to prevent mistracking. Off-center loading can also create an alignment issue, so ensure that chutes are positioned centrally over loading areas.

Since mistracking can be caused by material buildup, it’s also important to keep the belt conveyor, idlers, and pulleys clean. This will reduce wear on components, which could also cause mistracking.

Slight off-tracking issues can be remedied by “knocking idlers,” a practice in which idlers are skewed a small amount to correct an off-tracking belt.

SLIPPAGE

Belt slippage typically occurs around the drive/head pulley and happens when the belt and pulley do not have enough grip to adequately turn the belt around the pulley.

WHY BELT SLIPPING IS AN ISSUE

Belt slipping reduces productivity and efficiency, causing process upsets, or preventing the proper amount of material from being conveyed. It can also cause belt wear and damage, and put added stress on the motor, resulting in premature failure.

WHAT CAUSES SLIPPAGE

There are several reasons why a belt experiences slipping. This includes:

Low temperatures (cold temperatures can reduce the amount of grip between the pulley and belt)

Improperly installed pulley lagging

Buildup on pulley

Inadequate belt tension

Worn head pulley

Smooth pulley surface

Load that is too heavy for conveyor

HOW TO PREVENT SLIPPAGE

There are several ways to prevent slippage. Maintaining an adequate belt tension is critical to preventing slippage. It’s important to note, however, that while over-tensioning the belt may seem like an easy fix, this should be avoided, as it can stretch and damage the belt, as well as put added stress on the motor.

When there is not enough grip between the pulley and the belt, consider installing lagging. Lagging is a material added to the surface of the pulley for increased traction.

Alternatively, a snub pulley may be installed. A snub pulley is simply an idler installed at a point which increases the arc between the belt and pulley to improve friction between the two.

MATERIAL SPILLAGE

Material spilling off of the conveyor is also a commonly encountered problem. While spillage can occur at any point along the conveyor path, not surprisingly, it is most common at load and transfer points.

WHY SPILLAGE IS AN ISSUE

As with other issues, material spilling off of the conveyor belt reduces productivity and efficiency, encourages product/material loss, and increases wear on equipment. Further, as mentioned, spillage can be a significant safety hazard, falling on employees and increasing the likelihood of employees slipping or falling.

WHAT CAUSES SPILLAGE

In general, it is not uncommon to see some level of material spillage. Excessive fugitive material, however, likely indicates an underlying issue. Typical causes of excess spillage include belt misalignment, belt damage or wear, high-impact loading, and chute misalignment.

HOW TO PREVENT SPILLAGE

Spillage in general is managed by a well-designed conveyor system. The use of skirtboards and dust pick-off points are useful in reducing the potential for material spillage.

Ensuring that chutes are clear and located centrally above the loading zone will also help to prevent spillage. Additionally, impact beds for heavy loading prevent the belt from sagging, which can also release fugitive material.

Keeping conveyors aligned and in proper working order will also help to prevent excess fugitive material from escaping, as any deviation from proper operation has the potential to spill material.

PREVENTION IS KEY

Any one of the aforementioned issues has the potential to cause serious problems: premature equipment failure, unexpected downtime, employee injuries, and more. Even if problems do not reach a high level of severity, however, they still represent unnecessary hazards and losses in productivity and efficiency. For these reasons, a preventative approach to conveyor problems is always the best policy.

Regularly inspect the steel cord conveyor belt to look for signs of trouble: excessive material spillage, abnormal sounds, visual indicators, or other abnormalities. Always ensure that the equipment, as well as the surrounding area, are kept clean. Replace conveyor components that begin to show signs of wear.

By taking these measures, the potential for unexpected downtime and lengthy repairs is greatly reduced.

CONCLUSION

Troughed belt conveyors offer reliable handling in nearly any setting, but they can occasionally exhibit issues, particularly if not kept clean and maintained; carryback, mistracking, slippage, and spillage are some of the most commonly encountered issues when working with belt conveyors. While each issue presents significant risk and potential for damage, these issues are largely prevented by keeping a close eye on conveyor operation and performance, and promptly addressing any issues that arise.

FEECO manufactures custom belt conveyors and conveyor systems for use in nearly every industry, with expertise around hundreds of materials. Our Customer Service Team offers a full range of services for conveyors, from replacement parts, to repairs, and even inspections and conveyor audits. For more information on our belt conveyors or conveyor parts and service support, contact us today!

[keenobservationtiger]

Tiller mortality and its relationship to grain yield in spring wheat

A primary determinant of grain yield in barley (Hordeum vulgare L. emm. Lam) is the number of ear-bearing tillers per plant at harvest, which depends both on the production of tillers and on their subsequent survival to form ears. This three-year field study compares tiller production and survival in relation to final grain yield in three types of barley: 2-rowed winter (2rw), 6-rowed winter (6rw) and 2-rowed spring (2rs), grown in two contrasting environments. These three types differed significantly in shoot and ear number, the winter barleys showing higher tiller production, with the maximum number of tillers ranging from 798 to 2315 m−2 in 2rw, 711 to 1527 in 6rw and 605 to 1190 in 2rs. Grain yield across environments and years was strongly correlated () with the number of ears at harvest. The maximum number of shoots produced by each type of barley was inversely related to the mean temperature during the tillering phase. Tiller mortality was inversely related to the maximum shoot production, being significantly lower in barleys with less tillering capacity, i.e. the spring type (with average values of 34.3% and 42.7% in the two environments). The highest tiller mortality occurred before anthesis and, to a lesser extent, from anthesis to maturity. These data support the hypothesis that the principal cause for tiller mortality in barley grown under Mediterranean conditions is the competition between tillers for a limited supply of resources.

Spikeless tillers of wheat (Triticum aestivum L.) affect grain yield because of less than optimum effective plant population. This study was conducted to examine the genetic variability for tiller mortality, and its relationship to grain yield in diverse wheat lines. Twenty lines were evaluated in replicated field tests in 4 years at Rampur, Nepal. The characters investigated were maximum number of tiller produced, the number of reproductive tillers, tiller mortality, and grain yield. The lines differed significantly for all characters. The tiller mortality ranged from 7 to 30%. There were substantial effects of environment on all four characters. The entry-by-year interactions were significant for all traits, primarily because of changes in the relative genotypic differences for these traits in the four years. However, certain lines consistently ranked low or high for tiller mortality. There was a significant negative correlation between front tine tiller and grain yield in 3 out of 4 years. There was a positive correlation of highest tiller number with reproductive tiller number and with tiller mortality. Grain yield showed a nonsignificant positive correlation with maximum tiller number. The reproductive tiller number was positively correlated with grain yield. Results of this study indicate that spikeless tillers contribute negatively to grain yield and that genetic variation exists for tiller mortality in spring wheat.

Vegetative growth in the form of tillers is crucial to final yield in winter wheat (Triticum aestivum L.). To understand the impact management practices have on tiller initiation, a study was conducted using two seeding rates (1.9 × 106 vs. 6.8 × 106 ha−1) and two N timing applications (single vs. split). Tillers initiated in the fall made up the majority of spikes compared to tillers initiated from 1 January to the start of jointing (GS 30). Tillers initiated in March at either seeding rate produced very few kernels spike–1, low kernel weight, and contributed little to yield. At the high seeding rate, tillers initiated prior to 1 January were responsible for more than 87% of the grain yield. Tillers produced in January– February produced 5 to 11% of the final yield, while tillers produced in March contributed less than 2%. In contrast, at the low seeding rate tillers produced in January–February made up 20 to almost 60% of the final yield. Overall, this study shows the timing and rate of leaf initiation impacts yield and yield components. Earlier tillers have an advantage in that they have shorter periods of leaf development that result in more leaf area which in turn supports more kernel spike–1 and heavier kernels, thus more grain weight per spike. Timing of N (single vs. split) application resulted in no significant impact on tiller development, spike number, kernel number, kernel weight, or grain yield.

The number of spikes ha–1 is a critical yield component of wheat yield. Two factors contribute to the total number of spikes ha–1 at harvest, number of mainstem (MS) spikes and number of tillers plant–1. The number of tillers produced per plant is controlled by the environment during the period of tiller development from three-leaf stage to jointing (GS13–GS30) (Klepper et al., 1982) and the amount of tiller mortality that occurs from jointing to anthesis (GS30–GS69) (Jewiss, 1972; Rawson, 1971). Recent research has shown that the timing of tiller initiation and management factors such as seeding rate influence the rate of leaf development on each tiller which, in turn, influences tiller size and mortality (Tilley et al., 2015). The timing of tiller initiation and management factors such as planting date (Oakes et al., 2016) that promote leaf development could also influence other yield components such as kernels spike–1 and kernel weight. An understanding of when the most spikes are formed and the management factors that promote tiller formation during this critical period would help growers improve wheat yield.

Tillers can be formed at multiple nodes on the MS, and secondary and tertiary tillers can form from nodes on the tillers themselves (Klepper et al., 1982; Evers and Vos, 2013). Under glasshouse conditions Klepper et al. (1982) found that once a tiller is initiated, leaf development on the tiller proceeded at the same rate as leaf development on the MS. However, subsequent research has found that leaf development on each tiller proceeds at a slower rate than that on the MS or even on preceding tillers (Tilley et al., 2015). This indicates that tillers initiated first will always have an advantage in growth and development compared to those initiated later. This advantage will increase as time passes resulting in more leaf area. It is likely that tillers with more leaf area will produce more kernels, heavier kernels, and will be less likely to be lost to tiller mortality.

Timing of tiller initiation can also influence tiller mortality. Charles-Edwards (1984) concluded that self-thinning within plant communities is largely due to the lack of assimilate needed to continue growth and development within the individual stem which, in turn, can lead to a decrease in plant weight and eventually a decrease in plant yield. Some works have explored the purpose of rear tine tiller and the effects it may have on the plant as a whole and concluded tillers that abort may have benefited the plant due to assimilate and nutrient accumulation (Lupton and Pinthus, 1969; Palfi and Dezsi, 1960). However, Langer and Dougherty (1976) concluded that dead tillers had a negative effect on grain yield due to competition for assimilates and nutrients (Sharma, 1995).

Management practices such seeding rate and N application timing can influence the timing and rate of leaf and tiller development (Bauer et al., 1984; Tilley et al., 2015) and grain yield. Tompkins et al. (1991) concluded that grain yields will decline as seeding rates decline. This in part is due to a decrease in spikes. However, it was determined that grain yield can decrease at high seeding rate (HSR) (Gooding et al., 2002) due to a decrease in kernels spike–1 and a decrease in kernel weight (Puckridge and Donald, 1967; Tompkins et al., 1991). Tilley et al. (2015) found that seeding rates influenced the rate of leaf development. Phyllochron intervals (PI) were shorter for each tiller at a low seed rate (LSR) compared to the same tillers at a HSR. This resulted in more leaves on each tiller, more tillers produced and fewer tillers lost to tiller mortality.

Nitrogen is recognized as a vital nutrient needed for growth and development (Miller, 1939; Wilhelm et al., 2002). Nitrogen application timing recommendations for winter wheat in North Carolina (NC) are based on the tiller density (Weisz et al., 2001, 2011). Winter split applications are encouraged if tiller density <550 m–2. Otherwise the standard NC recommendation is to apply N at GS 30, the time when the wheat stem begins to elongate. Maidl et al. (1998) confirms that early N application increased plant density and concluded that N fertilizer treatment applied during stem elongation not only reduced tiller mortality but also led to high grain yield in both MS and tillers.

To understand the impact of the timing of tiller initiation and management practices on kernel development and yield, a method of counting and marking leaves and tillers was created to monitor tiller growth and decline. This monitoring of individual tillers resulted in the ability to measure the number of heads, kernel number and kernel weight each tiller produced, and its contribution to final yield. The objectives of this study were to: (i) measure yield and yield components of tillers initiated at different periods during the growth of wheat and how tillers initiated at different periods contribute to overall grain yield, and (ii) determine the impact of seeding rate and timing of N applications on the productivity and sustainability of tillers initiated at different periods during the growth cycle of wheat.

MATERIALS AND METHODS

Field Experiment

Field experiments were conducted at two sites in eastern NC and one site in western NC. At the Tidewater Research Station (TRS) in Plymouth, NC, experiments were conducted in 2009, 2010, and 2011. On a private farm in Beaufort County (BC) experiments were conducted in 2009 and 2010. On the third site in western NC (Piedmont Research Station [PRS] in Salisbury, NC) a single trial was conducted in 2011. The soil at TRS was a Cape Fear loam (clayey, mixed, thermic Typic Umbraqult) soil. At the BC site in 2009 and 2010 the experiment was conducted on a Cape Fear fine sandy loam (clayey, mixed, thermic Typic Umbraqult). The 2011 experiment at PRS was conducted on a Mecklenburg clay loam (fine, mixed, thermic Ultic Hapludult). In 2009, plots were planted on 3 November at TRS and 4 November in BC. In 2010, plots were planted on 10 November at TRS and 11 November in BC. In 2011, plots were planted on 10 November at TRS and 15 November at PRS.

At each site, Pioneer 26R12, a high yielding wheat variety in NC, was planted in 16.9-cm rows into a conventional tilled field following corn. The experimental design at all sites was a split plot design with main plots consisting of two seeding rates, 1.9 × 106 and 6.8 × 106 ha–1, and subplots consisting of 134 kg N ha–1 applied either as a single application in March or a split application with half applied in late January or early February and the remaining half applied by late March. In 2009–2010, the first N application was made on 15 February with the second split and single N application made on 22 March. In 2010–2011, the first N application was applied on 4 February while the remaining split and single applications were completed on 18 March. During the 2011–2012 growing season at TRS, the first split application was applied on 19 January with the final split and single N applications applied on 12 March. Applications at the PRS were applied 1 wk later on 26 January and 19 March. All treatments were replicated five times.

Disease pressure was minimum across all three site years and did not reach current threshold recommendations (Weisz et al., 2011). However, weed and insect control practices were applied. In 2009–2010 at TRS, thifensulfuren-methyl/tribenuron-methyl was applied POST at 0.04 kg a.i. ha–1 on 8 Mar. 2010. The BC location received the same application on 9 Mar. 2010. In 2010–2011 at both TRS and BC, thifensulfuren-methyl/tribenuron-methyl was applied POST at 0.04 kg a.i. ha–1 on 14 Mar. 2011. In 2011–2012 at TRS, mesosulfuren-methyl was applied POST at 0.33 kg a.i. ha–1 on 6 Dec. 2011 and thifensulfuren-methyl/tribenuron-methyl applied POST at 0.05 kg a.i. ha–1 on 1 Jan. 2012. At the PRS, chlorsulfuron/metsulfuron-methyl was applied PPE at 0.03 kg a.i. ha–1 on 3 Nov. 2011 and thifensulfuren-methyl/tribenuron-methyl was applied POST at 0.05 kg a.i. ha–1 on 28 Feb. 2012.

Individual plots were 24.4-m long and 1.98-m wide equaling a total of 48.31m2. Each plot was divided into three sections. The first 18.01 m2 section was designated for grain yield and grain sampling. This section of the plot was harvested using a Gleaner K2 combine with a Harvestmaster Graingage (Juniper Systems, Logan, UT) that recorded moisture, grain weight, and test weight. The TRS in 2010–2011 was harvested on 20 June and on 22 June during 2011–2012. Beaufort County in 2010–2011 was harvested on 23 June and PRS was harvested on 29 June during the 2011–2012 season. Grain weight was adjusted to 15.5% moisture before calculating yield.

The second section equaling 9.12 m2 was designated for marked samples. Five plants from each plot were marked and the number of full and partial leaves on each MS and tiller were recorded along with the total number of tillers at current growth stage. This was done once a month from planting to harvest. Throughout the 2009–2010 growing season, observations were made at TRS and BC on 22 December, 28 January, 1 March, 19 March, 7 April, and 26 April. During the 2010–2011 growing season, observations were made on 7 December, 31 January, 4 March, 2 April, and 30 April. During the 2011 growing season, leaf and Garden Tiller and Cultivator counts were recorded on 9 December, 2 January, 11 February, and 3 April at TRS and 15 December, 9 January, 24 February, and 13 April at PRS. Each new and existing tiller was noted using either a black, silver, or red permanent marker to mark leaf number. Black markings represented tillers that were initiated from planting through the end of December. Silver markings represented early winter tillers that developed from the first of January to the beginning of March. Red markings represented late spring tillers produced from March till growth stage GS30. The three colors used to track tillers helped categorize each individual tiller and determined whether or not they initiated in the fall, winter, or spring. Furthermore, tillers were marked on each subsequent leaf to track the number of leaves produced throughout the growing season. Harvest samples were taken in 2010–2011 and 2011–2012 at TRS, BC, and PRS on the same dates that the larger plots were harvested. At harvest, each of these five plants were clipped and placed in individual bags. For each plant, the MS and tillers were separated by color markings (black, silver, red) counted and hand threshed to determine the number of spikes and grain weight spike–1 for each tiller initiation period. The data for all five plants were averaged to represent values for each plot.

The last 21.18 m2 of each plot was reserved for destructive sampling. Method for destructive sampling consisted of a 2-m stick and a garden shovel. A trench, encamping an area of 0.33 m2, was carefully dug around plants to a depth of 15 cm and the plants were then excavated from the destructive sampling area. Samples were taken on 17 June 2010, at TRS and BC. On 15 and 20 June 2011, destructive samples were taken at TRS and BC. Destructive samples were taken at TRS and PRS in 3012 but were destroyed before they could be processed. Leaf counts were taken from each individual stem and recorded. Leaf numbers were determined by counting the nodes on the plant. This was done by splitting the plant at the base and finding the small (0.6–1.25 cm) gap between the compressed nodes and the first separated node. The first separated node was counted as the fifth node (fifth leaf) and subsequent nodes (leaves) were counted in ascending order. Plants were separated into classes corresponding to the periods of tiller initiation (black, silver, and red) based on leaf number and the ratio of stems found in each initiation period in the marked samples. This ratio was determined by counting the number of MS or tillers from each category (black, silver, and red) in the five marked plants described above and dividing that number by the total number of MS or tillers produced in these same plants. Using the ratio of MS or tillers that were initiated from planting to the end of December (Black), the same ratio of plants with the highest leaf numbers in the destructive sample were designated as having been initiated during this period. Plants with the next highest leaf number were considered initiated during the period from 1 January to the end of February; and plants with the fewest leaves were considered initiated after 1 March. Spikes from samples representing each initiation period were hand threshed and grain weight, kernel number and 100 kernel seed weight were measured.

Statistical Procedures

For the marked plant samples the data taken from TRS in 2010–2011 and 2011–2012 at BC in 2010–2011 and PRS in 2011–2012 were analyzed using a repeated measures design with the Proc Mixed procedure in SAS (SAS Institute, Inc., Cary, NC) to determine if there were differences in the number of spikes plant–1 and grain weight spike–1 among site-year, tiller initiation periods (planting to 31 December, 1 January to 28 February, and after 1 March) seeding rate, and N application timing. In all cases, site-year, seeding rate and N timing were treated as fixed effects, while blocks and the interactions with blocks were treated as random. When differences were detected, Fisher’s Protected LSD was used to separate means.

In the destructive sample plots some samples were lost in 2011–2012. Therefore, only samples taken in 2009–2010 and 2010–2011 at TRS and BC were used in the analysis. The Proc Mixed procedure in SAS (SAS Institute, Inc.) was used to determine if there were differences in spikes m–2, kernels spike–1, weight per 100 kernels, and grain yield among site-years, mini power tiller tractor initiation period, seeding rate and N application timing. As with previous analysis, site-year, seeding rate, and N timing were treated as fixed effects; while blocks and the interactions with blocks were treated as random. When differences were detected, Fisher’s Protected LSD was used to separate means.

Grain yield from the large 18.01 m2 section of each plot for the 2010–2011 and 2011–2012 seasons at TRS and BC were analyzed using the Proc Mixed procedure in SAS (SAS Institute, Inc.) to determine if there were differences in grain yield among site-years, seeding rate, and N application timing. These site-years were chosen so that the grain yield from the large samples could be compared with that calculated from the small 2-m samples.

[keenobservationtiger]

Solving problems on the tube mill

Tube mill machine line face a variety of challenges every day in their effort to produce high-quality tubing in a cost-effective and productive way.

This article examines some of the typical problems producers encounter, some common causes of these problems, and some ideas for how to solve these problems.

Lost Mill Time During Operation and Changeovers

Often, excessive downtime during normal operation or tooling/job changeover can be attributed to one or more of the following causes:

1. No written procedures for setup. Every mill should have written procedures for all operators to follow. The machine, tooling, and steel are fixed factors in the mill setup equation; the only variable is the human factor. This is why it is so important to have written procedures in place to control the process. Written procedures also provide a tool for troubleshooting when problems arise.

2. No setup chart. Tweaking the mill during setup loses valuable setup time. Operators must work the tooling the way it was designed. This means setting up to the parameters of a setup chart.

3. Lack of formal training. Formal training helps operators perform the procedures for carbon steel tube mill machine and maintenance and ensures that all operators are on the same track.

4. Disregard of parameters from previous setup. If the Galvanized tube mill machine has been set up according to the written procedures and setup chart, the operator can write down the numbers from the digital readout on the single-point adjustment (SPA) unit, allowing the next operator to set up where the first left off. Setting up to the numbers can save as much as 75 percent of total setup time, as long as all the other tips discussed in this article are followed.

5. Mill in poor condition. A poorly maintained mill costs valuable time and scrap during setup and operation. The mill must be dependable so that the operator is not chasing mechanical problems during normal operation and setup. A good maintenance program, as well as rebuilds or upgrades when necessary, is essential.

6. Mill in misalignment. Tube mill misalignment, poor mill condition, and inaccurate setup account for 95 percent of all problems in tube production. Most mills should be aligned at least once a year.

7. Tooling in poor condition. Operators must know how much life is left in the tooling before the next scheduled rework. Running the tooling until it cannot produce tubing anymore not only wastes valuable mill time, but produces scrap and affects delivery schedules. All tube production companies should have a tooling maintenance program in place.

Any of these causes of lost time on the mill can have varying degrees of value, depending on the severity of the conditions. The bottom line is, the more of these items that are in control, the less downtime on the mill.

Splitting in the Weld Zone

Weld zone splitting can be a result of some or all of the following:

Overly narrow strip with insufficient material to forge

Poor alignment or setup

Insufficiently worked fin passes, so the edge is not prepared for welding

Poor slit edge

Off-center strip approach (strip rolled over) to the weld box, preventing forging between the weld rolls

Nonparallel edges entering the welding machine

Inappropriate weld power for mill speed

Poor-quality steel with improper chemistry

Irregular Size in the Sizing Section

When irregular size occurs in the sizing section, the problem may not necessarily be in the sizing section itself. The operator also must check the setup in the breakdown, fin, and welding section of the mill to ensure proper presentation to the sizing section. If the forming section sends improperly formed tube to the sizing section, irregular tube size can result.

The operator also should check for bent shafts, oversized bores on the tooling, or undersized outside diameters (ODs) on the driven shafts. The integrity of the side roll boxes also should be checked.

In addition to these checks, the operator should consider the following questions:

Is the weld size in accordance with the setup chart?

Is the weld size round?

Are the strip edges parallel, with no step going into the weld rolls?

Is the weld scarf smooth?

Are rework shims installed under the bottom driven shafts to maintain the metal line?

Are the correct spacers installed on the driven shafts and to the correct length?

Are the bearings and bearing blocks tight?

Are the side rolls parallel?

Is the tube being cooled properly?

Are all the drives coordinated and adjusted to match the rework of the tooling?

Has the chemistry or hardness of the material changed?

Weld Chatter

Weld chatter is the inability to achieve a clean cut of the outside weld bead after welding. The scarf knife chatters and produces a ribbed or rough cut on the OD of the tube. This is unacceptable in most of the end products produced by the tube and pipe industry.

Several techniques can be used to prevent weld chatter.

The scarf knife should have a slightly larger radius than the tube OD. This will provide a concentric, clean cut.

An ironing pass should be used after the scarf stand. As the name implies, this stand irons out any hot imperfections the scarf knife may leave behind. It also adds a tremendous amount of stability to the scarfing operation.

On mills that employ induction welding, moving the induction coil upstream a bit and away from the weld rolls helps temper the edges of the strip by preheating them before welding. This results in a more malleable material that is softer and easier for the scarf knife to cut.

The heel of the scarf knife or insert should be ground to an angle of 18 degrees from the horizontal, and the tool should be set at an angle of 15 degrees from the vertical. This provides the proper clearance so the knife does not drag on the tube or pipe. A straight up-and-down approach to the tube or pipe invites chatter.

In general, several tube mill components should be checked on a regular basis. This should be done at least monthly, but should be based on the usage. A higher production rate or running heavier metals through the mill requires more frequent checks. Shafts should be checked for OD, looseness, bending, and parallelism. Shoulder alignment should be checked, and the integrity of the entry table, drive stands, side roll boxes, weld box, and Turk's head units should be ensured. Of course, rolls should be checked to ensure they have been installed on the correct stands.

Once a year, the mill should be aligned. A mill alignment usually takes one or two days and is most often done by a professional. Every day, the mill operator should use a setup chart and follow all operating procedures.

The operator also should know the chemistry, Rockwell hardness, width, and thickness of the strip entering the mill and should document these values. Tube size should be measured between each pass.

Most important, for high-quality, consistent results in tube producing, an operation standard should be established for all employees to follow.

High‐frequency welded carbon tube mill machine line is designed to produce round tube diameter of 10.0 – 38.1mm, and wall thickness of 0.4 ‐1.8mm.This line utilizes roll forming to process steel strip into various shapes. Using high frequency induction heating, this line is capable of producing section material of various diameters and sizes by squeezing weld seam together into closed shape. The application of advanced aperture technology, PLC automatic control system and British Eurasia Digital speed‐regulating unit ensure that the production line works reliably and operates and maintains easily.

Every detail is the evidence of showing our company's strength and works's hardworking and it is the basical assurance of every machine we are producing.We are targeting to provide our customers with high-quality equipment or machines.

Botou Boheng Metallurgical Equipment Manufacturing Co.,Ltd was established in 2003, and located in Botou city Hebei province. Boheng is a high and new-techonology enterprise specialized in design,development and manufacture of ERW welded pipe equipment,high precision slitting & crossing-cutting equipment,spiral welded pipe equipment,cold forming equipment and crossing-cutting equipment,spiral welded pipe equipment,cold forming equipment and rollers. Boheng is the pioneer that had the key processing technology of the international advanced whole set welded pipe mill. Boheng always adhere to the enterprise policy "contribute to the society with excellent techniques,high quality products and perfect service".

Technology capability:

(1)Engineer able to service overseas

(2)Work out reasonable investment scheme,selecting rational model unit

(3)Provide free equipment layout,factory planning for you

(4)Provide free equipment foundation drawing,if necessary,offer technical guidance on-site for equipment foundation construction

(5)Provide equipment installation and commission,ensure the normal operation of production line

(6)Provide professional technical training to help your stuff familiar with equipment ASAP

[keenobservationtiger]

Cotton Buds Making Business

The cotton swab making machine business is rapidly progressing in India. Cotton is the staple fiber made from the natural fibers of cotton plants. The cotton made from the genus Gossypium is primarily composed of cellulose, which is an insoluble organic compound that is a soft and fluffy material. Cotton is the most important fiber crop, which provides the basic raw material to the cotton textile industry. Cotton is grown in tropic and sub-tropic parts and requires uniformly high temperature and is a Kharif crop; it is sown and harvested in different parts of India depending upon the climatic conditions.

China, the USA, and India are the world’s major cotton-producing countries, accounting for about 60% of the world’s production. China alone consumes around 40% of the world’s cotton, and it is a significant export revenue source for major cotton-producing countries of the world.

Cotton is cultivated around 117 lakh hectares in India and accounts for about 37.5% of the global cotton area, and contributes to 26% of the global cotton production. Cotton holds an essential place in the Indian textile mills, and it is used as a primary raw material of India. Cotton provides livelihood to around 60 million people of India by means of cotton cultivation, processing, marketing, and exports.

Cotton buds are the most common item which is used for cleaning the ear, first-aid, cosmetic application, cleaning, and arts and crafts. The cotton buds are composed of small wads of cotton which are wrapped around a rod made of wood, paper, or plastic. The cotton buds were developed in 1923 by a Polish-American Loe Gerstenzang which later became the most widely sold brand name of cotton swabs.

The cotton bud with a single tip on a wooden handle is mostly used in medical settings and is the traditional cotton buds. The cotton buds used for domestic purposes are usually short, about 3 inches long, and double-tipped. Traditionally, the handles of the cotton buds were made of woods while later it was made of the rolled paper and sold in large quantities. The cotton buds are available in a wide variety of colors, such as blue, pink, or green. The manufacturing of the test swabs in a record time of seven days is a dream come true under the ”Make in India” initiative which has conceptualized the production and provided employment to so many unemployed people in India.

The cotton buds are most commonly used for cleaning the ear by removing earwax.  The cotton buds are used for domestic purposes such as cleaning and arts and crafts purposes. The medical buds are used to take microbiological cultures which are usually rubbed into the affected area and wiped where the bacteria grows across the culture medium. They can also be used to apply medicines to selective areas targeting to remove substances or clean them. They can be used as an applicator for applying cosmetics, ointments, or other substances.

The cotton buds are also used to take the DNA samples by scraping cells from the inner cheek in the case of humans. The cotton swabs are also often used in the construction of the plastic model kits while paintings. They are also frequently used for cleaning the laser diode lens of an optical drive in conjunction with rubbing alcohol. In addition to his, they are used to clear the large parts of the computer such as video cards and fans and also used widely to clean video games cartridges in the past.

With so many uses, the demand for cotton buds in the market is growing at a rapid rate and is an essential tool for the healthcare of all individuals irrespective of age, race, culture, or religion, etc. keeping this in mind, the idea to start the automatic cotton swab making machine business is a golden opportunity for the young and aspiring entrepreneurs.

With the increased diversity of product ranges from adult-centric to baby and child-centric and increased popularity of cotton buds in the modern as well as in traditional retailing has increased the sales of the cotton buds to grow. With the rising demand, the locally produced cotton buds have become popular across rural India. it has also become popular in small as well as in metropolitan cities because of the availability of the cotton buds at a much lower price as compared to the branded products have been a key focus for the small manufacturers in India. Therefore, it is an ideal business for employing in the Rural areas as well as it will promote the ‘Make in India” initiative of the Modi Government.

The Government of India is promoting all the manufacturing units, especially in the areas where China enjoys a big share in the global market. The government to achieve the Atma Nirbhar Bharat is pushing the exports by giving various aids to the small and marginal businessmen and it aims to reduce the dependency of the country on the imported goods.

The government through various joint ventures and supporting the local businesses is expanding India’s share in the global market. Keeping this in mind, the government has announced various production-linked incentives for manufacturing the earbuds. This is a great opportunity for Indian earbuds manufacturers to raise their business. It is a big step towards making India self-reliant and manufactures their products. Almost 260 schemes are contracted by the Tri-services at an approximate cost of Rs. 3.5 lakh crores and with the latest embargo on the import of 101 items, the contracts worth Rs 1, 30,000 crore is expected to be placed upon the domestic industries in India.

Registration:- To start the buds manufacturing business in India, the first and foremost thing is the registration of your firm either as a proprietorship company or as a partnership firm. One must register the company as a Proprietorship firm if he has to start his buds manufacturing business as One Person company. To start a partnership firm, one must get registered with the Registrar of companies (ROC) and register as a Limited Liability Partnership (LLP) or the Private Limited Company.

GST Registration:- To start a business, it is now mandatory for any business to obtain a GST number, tax identification number, and an insurance certificate.

License for Trade:- Trade license is very important to be acquired to start a buds manufacturing business. It can be obtained from the local bodies of the respective states.

MSME or SSI Registration:- To avail of the government schemes and benefits, one must obtain the MSME or SSI registration. This will help the businessman to receive all the governmental benefits arising from various schemes.

Trademark:- It is required to make sure to register the buds manufacturing business with the trademark which will help in protecting the brand name.

Before starting a semi automatic cotton swab making machine business, one has to make sure to select the proper machines which are proper for operations suitable for your business.

Following are the description of machines used in the cotton buds making business-

Automatic Cotton Swab Packing Machine : –

The automatic cotton bud making machine is the machine that uses the computer PLC process control and warm wind drying technology is used to help to absorb the coating layer. The microcomputer servo motor aids feed the cotton layer and wrap the absorbent material. In this technology, there is no requirement for a different packaging machine separately.

Spindle Fabrication Machine : –

The paper spindles are processed with the help of a dyeing cutting machine from a heavy grade paper and then a thin layered paper is rolled around it to make it light. While a wooden spindle is developed with the help of a lathe machine process. The plastic spindle is made from the extrusion molding process machine, where the plastic is melted and extruded through a die and sent to a hopper machine.

Packaging Machine : –

The cotton buds are sent through the packaging wheels where the buds are rolled with the pouch. A sensor is attached to the packaging wheel which counts the buds and places them into the packaging bag which is packed with the packaging wheel.

The automatic cotton swab packing machine does not require a lot of space for its operation and it can be started from home. Anyone can start the business even from home this will reduce the cost of investment. The cotton buds making business has the potential to give a good place in the market by becoming a high profit earning business in a short period. With the increased demand for cotton buds, the business is very ideal for start-ups and young entrepreneurs.

In the times like this where the pandemic has left no nation in a mess, India has started the manufacturing of indigenous swabs or cotton buds for the testing of Covid-19. A Mumbai based Micro, Small and Medium Enterprise (MSME) and Tulips has got a green signal from the Indian Council for Medical Research (ICMR) and the National Institute for Virology in Pune. These firms have started manufacturing the polyester-spun swabs which are way cheaper than the imported swabs from the US and China. This has helped various small and indigenous manufactures to retain their livelihood and it has also resulted in producing cheaper testing kits at an affordable price.

We Indians have in reality converted the deadly pandemic into an opportunity and the government through various initiatives has been aiding the cotton buds making business. The government is also being aided by various Non-governmental Organisations like Aatmnirbhar Sena is working very hard to provide finances and cheap credit to aspiring and innovative minds and fulfilling their dream of starting the business.

Therefore, the growth and development of cotton and cotton made products has a vital role in the overall development of the Indian economy.