Compressor Check Valves: What They Do and Why They Fail

Compressor MaintenanceA compressor’s check valves perform an essential function that’s vital to the operation of a compressed air system. Located between the compressor and the air receiver tank or main header, a check valve is designed to prevent air from bleeding out of the tank or header and back into the inlet line when a compressor shuts down. Unloader valves, meanwhile, allow air to bleed out of the compressor line to reduce load on startup.

A check valve typically consists of a valve mechanism that keeps the header sealed when there is higher pressure in the header than on the compressor side. As a result of this design, a faulty check valve may sometimes leak at lower pressures but not at higher pressures. In fact, leaks can often be traced back to a faulty check valve.

So what happens to compressors when their check valves fail?

In addition to causing leaks, a check valve failure can damage the compressor itself. If a check valve fails in its open position, it can allow air to leak back from the header into the compressor when it’s not running. This, in turn, can cause the compressor to spin backwards, thereby damaging it in the process. More often than not, however, we see check valves fail when they’re closed. When this happens, the stuck valve can cause pressure to increase uncontrollably, ultimately leading to a compressor surge.

The good news is, there are steps you can take to reduce the likelihood of check valve failures in your compressed air system.

To begin with, it’s important to select an appropriately-sized check valve based on the valve’s orientation (vertical or horizontal), your compressor’s flow conditions and type of media (air or another gas). Your compressed air system should also be outfitted with filters to keep compressor lines and check valves free of debris. Finally, be sure to conduct routine maintenance on the system’s valve and compressor lines. This includes flushing the system, disassembling valves to inspect for corrosion and replacing damaged valves if necessary.

At Case Controls, we can help you maintain your compressed air system to prevent check valve failures and other common performance issues. To learn more about the onsite and remote support services we offer, feel free to give us a call at (812) 422-2422 or contact us online today.

A Brief Explanation of Centrifugal Compressor Valves

Industrial compressorThe valves in a centrifugal compressor are responsible for regulating air intake and the bypass air.  This regulates the air discharged and also works to prevent surge. Within a compressor, you can typically find several different types of valves that each serve a unique function. Learn more about a few of the most common compressor valves below!

Butterfly Valve

This type of valve can be found in a wide variety of industrial applications. In compressors, butterfly valves are often used as air inlet valves. An inlet butterfly may be either electronically or pneumatically actuated. As the butterfly valve closes, effectively reducing the inlet flow and limiting the compressor’s ability to generate pressure and airflow.

Ball Valve

This type of rotary valve functions similarly to a butterfly valve, but it regulates pressure using a ball with a hole through it instead of a circular plate mounted on a rotating shaft. By virtue of this design, ball valves are able to create a more complete seal than butterfly valves, which makes them ideal for regulating the flow of gasses. They are also generally less prone to pressure drops than butterfly valves.  These are mainly used for the blow off function.

Inlet Guide Vane (IGV)

This is another common type of inlet valve, but its design is distinctly different from that of a butterfly valve. An IGV regulates airflow using a series of radial blades or “guide vanes” arranged in the intake. When the valve is open, the vanes are parallel to the airflow. When it’s fully closed, the vanes are perpendicular to the airflow. As the guide vanes are rotated from open to partially closed, they cause the air to rotate in the same direction as the impeller. This reduces the incidence angle of the incoming air and consequently reduces that amount of energy required to produce pressure. This design characteristic makes IGVs an especially efficient type of intake valve.

Blow Off Valve (BOV)

This type of valve is used to prevent compressor surge. A BOV is also referred to as a bypass valve, but BOVs vent excess air into the atmosphere. The BOV can be found on the intake pipe between the turbo and throttle body.

These are just a few of the many components that work together to make a compressor function effectively. At Case Controls, we design and build industrial control systems that optimize compressor efficiency and prevent costly breakdowns. To learn more, feel free to give us a call or contact us online today.

An Introduction to the Industrial Internet of Things

Case Control SystemsThe revolutionary technology that has come to define the Information Age can allow us to do much more than just surf the web and check our emails. Over the course of the past few decades, the Internet has had a similarly transformative effect on industrial infrastructures as well.

The Internet of Things (IoT) is a catch-all term that refers to any devices or appliances that are networked together via systems such as Ethernet, WiFi, Modbus TCP or RTU. It’s become a popular buzzword among tech writers in recent years, but IoT devices have been successfully implemented in industrial settings for quite a while now. In fact, we showcased this technology way back in 1997 at the Rockwell Automation Fair. Today, we offer native Ethernet/IP connectivity on all Case Control Systems.

So what benefits does the IoT offer in the context of compressor controls?

First and foremost, connected compressor controls offer superior efficiency and reliability compared to traditional air supply systems. When multiple air compressors are connected to a programmable logic controller (PLC), a master control system can monitor the air supply system and make continuous adjustments to keep the compressors running at maximum efficiency. This makes it easy to evaluate compressed air KPIs over time. In the event that one compressor in the system fails, the master software can even step in and automatically trigger another compressor to pick up the slack. This, in turn, can make the air supply system far more stable and reliable.

Interested in learning more about the IoT capabilities of our compressor control systems? Give us a call or contact us online today to speak with a representative!

Understanding the Importance of Pressure Dew Point Monitoring

Compressed air systems are utilized in many different processes in a variety of industries. Dew point monitoring is often essential with compressed air systems. This is what you need to know about the importance of monitoring dew point.

The dew point is the temperature at which condensation will form. This term is familiar to most people from weather forecasts. It is a useful measurement because it correlates to the amount of water vapor in the air or in a gas. Dew point is a term that refers to the dew point of a gas at a pressure that is higher than atmospheric pressure. The dew point temperature of a gas increases with pressure. The dew point is important when working with many compressed air systems.

The dew point is not important in some systems. Tire inflation compressors, for example, are not likely to be significantly affected by a variable dew point. In many applications, however, the dew point is important. Pipes with excessive condensate from a higher dew point freeze up if there is too much water. In many industrial applications, excess moisture in a compressed air system may lead to equipment problems. The header pipes made of carbon steel can rust, and pressure vessels can be compromised due to corrosion and rust. Actuators at a production line can rust and corrode due to excessive water making it through the compressed air system.

There are many applications that utilize compressed air to provide conveyance like food powders, plastics and even carbon black. These application require dew point be kept low to avoid product contamination. Consideration should also be given to controlling the dryer to the targeted dew point. The atmospheric moisture will change as the weather changes. Therefore, there may be energy savings possible by controlling the dew point.

Dew point monitoring can be achieved by installing high-quality dew point sensors and monitors in the compressed air system. The use of a pressure dew point monitoring system allows you to be sure that you are reliably maintaining the desired moisture level in a compressed air system. There are many factors that can affect the reliability of a dew point monitoring system, making it worthwhile to partner with experienced compressor control experts.

Case Controls provides high-quality control solutions for industrial compressed air systems. Our solutions have been proven over time with a variety of compressors. Contact us at 812-422-2422 to learn how our expertise and resources can improve the performance of your compressed air system.

Compressor KPIs: What Are They and How Can They Be Used?

If you own or operate an industrial operation that relies on compressed air systems, then you know exactly how important it is for these systems to run as efficiently as possible. Inefficient compressed air systems can cost companies thousands of dollars every year and take a toll on equipment over time. Therefore, it’s important for companies in the industrial sector to take a look at all of the Key Performance Indicators, or KPIs, associated with their compressed air systems. KPIs can be used to evaluate the performance of systems and to improve the overall compressed air efficiency in your facility.

There are a handful of KPIs that can be measured during routine inspections of compressed air systems.

For efficiency, power consumption is a KPI. There are many companies that don’t monitor their power consumption closely enough over time to see if they could reduce it, and again, it ends up costing them money. The basic measure could be CFM/HP or CFM/KW (the inverses KW/CFM is often used). It would be good to compare the CFM to standard SCFM conditions to adjust for temperature and other atmospheric conditions. It is important to measure the actual CFM going to the plant. If done properly this KPI will provide valuable information as to how well the supply of compressors online is matched to the demand.

One KPI that represents demand is to compare CFM to production measures. Examples of this are CFM/parts produced per week or month. It could also be CFM/tons produced. This KPI will provide a good indication of compressed air wasted at the process or an increase in leakage or artificial demand.

One other important KPI is system pressure. As the pressure increases in your system, so will the power consumption, which could end up costing you additional money. By keeping your system pressure within an acceptable range, you can cut costs and make your system more efficient. The KPI can be measured as an average pressure as well as a standard deviation around that average.

There are other KPIs that can also be monitored to evaluate how efficiently a compressed air system is running as well. Air flow, temperature and carbon footprint are all KPIs that you should be keeping an eye on. By keeping track of KPI data and crunching numbers based on your findings, you can make your operation running more efficiently in the future. As it is often stated, you cannot control what you do not measure.

At Case Engineering Inc., we’ve been designing, maintaining and servicing compressed air control systems for more than 30 years. Contact us at 812-422-2422 to learn more about how we can make your company’s compressed air system better and more efficient today.


Understanding Air System Artificial Demand

Companies that rely on compressed air systems are constantly looking for ways to make them run more efficiently. Many of these companies end up spending more money than they need to on an annual basis simply because their existing air systems are inefficient and wasting air. One of the many reasons that this can happen is due to something called artificial demand.

Essentially, artificial demand is, according to Compressed Air Challenge, “the excess volume of air that is required by unregulated end uses as a result of supplying higher pressure than necessary for applications.” Artificial demand in an air system is something that needs to be considered as part of the overall air system, and it should be monitored to make sure your air system is running properly.

In more lay terms, this artificial demand is the extra pressurized air in the system that is not being used or is being generated even though the attached components or end applications are not being used.  The higher pressure causes more CFM to flow through orifices, leaks or similar types of openings.  This means that the system is always running as though it needs to provide pressurized air throughout the system, even if the actual demand isn’t there. For example, a 20 PSI increase on a ¼ pipe will cause 10 more CFM to flow out the opening.

Many compressed air users don’t realize artificial demand exists and therefore don’t know how to reduce its effects. Companies can reduce the artificial demand by implementing an overall controls system to maintain the compressed air system at the actual pressure that is required. This minimizes extra strain on generation units, reduces pressure being held throughout the system unnecessarily, and can decrease utility costs while increasing the lifespan of the system overall.

Is your company currently using an air system where the supply and demand are out of whack and not conducting true load sharing? Are you operating your air system at a higher pressure because it is not under control?  Case Controls can help you with this problem by offering up real solutions. We can provide you with compressor management equipment that will bring your artificial demand down and see to it that your equipment doesn’t waste any energy or money when it’s running. Whether you want to install AirMaster load sharing solutions for centrifugal compressors or you want us to take a look at your current setup and give you our opinion on your best course of action, we are happy to help you get your facility under control.

Call us at 812-422-2422 today and find out how we can help you get the most from your compressed air equipment.

Safety Concerns with Compressed Air

Compressed air is something that’s often utilized in industrial, commercial and agricultural workplaces. It has a lot of practical applications, and it is so useful that it is often labeled the fifth utility, alongside other utilities like water, electricity and natural gas in terms of importance to an industrial facility. Compressed air, however, can be very dangerous if you don’t take all of the necessary safety precautions before using it. Let’s review some of the potential dangers associated with using compressed air on the job site.

Compressed Air GunWhat’s the Risk?

Compressed air is – as the name implied – pressurized and compressed to such a degree that blowing air directly at a person can actually end up causing injury. In serious instances, this air can penetrate the skin and even causing lead to a life-threatening air embolism. Likewise, compressed air can rupture ear drums and even displace eyeballs if you don’t pay attention and operate air-powered equipment as carefully as possible.  OHSA restricts the maximum of 35 psi of air be used for blowing applications or process that people can be directly exposed.

Tiny particles can also be blown by compressed air, and these small grains of dust, dirt or other materials can cause extensive damage to skin and various body parts. Even if compressed air doesn’t actually come into contact with someone, the noise that it creates can harm their hearing. These are just a few of the most common dangers linked to compressed air as reported by the Ohio Bureau of Workers Compensation.

Another concern results from the fact that compressed often contains some level of oil.  This can result in oil being injected into the body.  It can result in oil injection injuries, similar to high pressure hydraulic.  Loss of limbs or even death can be the consequence of this type of injury if immediate medical attention is not provided.

Staying Safe

To prevent these problems, you should never aim compressed air at another person. You should also avoid using compressed air for cleaning purposes as the blowing air could lead to unintended harm. It’s also important to always wear earplugs when you are working around compressed air to protect your hearing.  There are also OHSA approved nozzels and regulator that can be applied to help prevent the injuries.

Finally, if you use machinery that relies on compressed air, you should inspect it periodically to ensure that all air hoses and fittings are properly installed. Compressed air can put a lot of strain on the hoses and components attached to the system, which means that hoses can come loose from time to time. This can turn into real hazard if a hose comes loose, causing it to whip around wildly and blowing pressurized air in every direction.

If you use industrial compressed air utilities in your line of work, Case Controls can help you make sure it is being used in an optimal way. Contact us at 812-422-2422 today to speak with one of our representatives about the compressed air automation services we provide for our customers.

Case Controls: A History of Successes

Case Controls has been helping companies design and build world-class control solutions for all of their industrial compressed air systems for more than 30 years now. While the cutting-edge and innovative solutions that we have created have played a big role in our success over the years, we couldn’t possibly be as successful as we are today without our excellent state-of-the-art facility in Evansville, Indiana and, more importantly, the staff members who fill it and help us to be the best in the business.

The building that we use as our central location was built in 1916 and used to be the Illinois Central Freight Depot, a freight train station in that shipped and received merchandise to and from locations around the region, as Historic Evansville notes. With a design that was originally built to house freight for the railroad, this structure has handled the past century well, and still remains structurally sound and reliable for our needs today. Take a look at this video from YouTube user FeeltheHistory to see more of the history of the building.

When Case Controls took over the building in 1986, we refurbished it completely, and we have continued to update and make improvements to it every year since. As the sole occupant in the building, we have been able to convert the expansive space to meet all of our needs, and now have designated areas tailored to function for training, testing, engineering and manufacturing inside of the building. Each of these areas plays a pivotal role in our ability to deliver the best products and services to our customers.

While our building has evolved over the years, many of the long-time employees on our team have remained the same and continue to work hard to help Case Controls deliver our compressed air solutions.

Case ControlsJohn Craddock started Case in 1986 as a general automation house. We soon became one of the first authorized Allen Bradley distributors in the U.S., and for 25 of our 31 years, we have specialized in automated air compression systems, with it becoming our sole focus under Craddock’s leadership roughly 19 years ago.

Another one of our longtime employees is Jeff Small, who started at Case in 1998. As a member of our team for nearly two decades, Small has worked up in the company, Case Controlstaking on more responsibilities and duties, and now manages all aspects of panel fabrication. It’s employees like Small that make Case such a special place to work and allow us to continue offering reliable and purpose-built solutions for our clients.

Throughout our history, Case Controls has adapted to meet the needs of changing technologies and the demands of our clients, and we remain committed to continuing to grow and serve our customers well into the future. We welcome the opportunity to work with companies who need help with their compressed air automation and hope that you will consider working with us. Call us at 812-422-2422 today to learn more about how Case Controls can assist you and your facility.

New Master Controls Help Paper Company Save $560K

Like many other companies out there, a paper company in Eastover, North Carolina, hit a point recently where they felt as though their plant wasn’t as efficient as it should be. They were using two 800HP Joy centrifugal compressors with obsolete Quad III controllers and three Atlas Copco fixed speed rotary screw compressors with obsolete controls, and they felt as though they were wasting a significant amount of compressed air and energy every single day.

They were right. The company called on Case Controls to take a look at their system and help them decide whether or not new master controls would solve the problem they were facing. After surveying all of their equipment, we ultimately concluded that they could cut down on their wasted energy by installing a new AirLogix® control system and Quad III retrofit kits for their two Joy centrifugal compressors. Additionally, we provided the company with AirLogixPD™ rotary screw controls for their Atlas Copco machines.

We also installed an AirMaster™ load sharing system to manage demand across all compressors. There was no need to add a separate programmable logic controller (PLC) system to manage this load sharing since the rotary screw compressors were upgraded with CompactLogix PLCs™, which made the AirMaster™ floating master architecture a feasible solution.

During two, two-week outages, we made the upgrades to the centrifugal and rotary screw systems in sequence, and when the work was completed, the company found that our solutions helped the plant out immensely. The increased efficiency in operations has been documented as more than $560,000 annually – an incredible savings in operational costs. With compressors no longer running when there was no demand, excess air production dropped thanks to their new master controls, creating a vastly more efficient facility.

If you run a business that relies on air compressors and you think that you might be spending too much money every year on energy, you should consider doing what this paper company did and investing in new equipment. Case Controls can supply you with the products and services you need to increase your efficiency, often finding solutions that can save your company thousands of dollars per year, meaning your investment will frequently pay for itself. Contact us at 812-422-2422 today to see how we can help you.

Coffee Processor Perks Up Savings with New PLC System

Until recently, a major coffee processor was operating a plant that utilized a very inefficient system. The plant relied on a 350 Centac centrifugal compressor, a 500 Joy centrifugal compressor, two 500 HP Atlas Copco rotary screw compressors, and two 800HP Atlas Copco rotary screw compressors – all of which provided plenty of power, but inefficiently. The machinery was used to provide compressed air to convey coffee throughout the processing facility – a primary function of the plant – but to manage the large swings in airflow demand, plant employees had to manually control the different compressors throughout the day.

While there was plenty of capacity available at plant, the lack of an automation system to control the compressors meant fluctuating demand and difficult to manage. As you might guess, this, in turn, led to the company wasting a significant amount of compressed air every day, and over time, it cost the company hundreds of thousands of dollars per year. Plant management commissioned a study to find out how they could start saving money and brought in our team to help improve their operations.

Case Controls stepped in and made a number of improvements that helped the plant work more efficiently. While the company was already using AirLogix® controls on their centrifugal machines that were installed by Case Controls, however there was no network that connected the compressors. We installed a programmable logic controller (PLC) system that communicated with all of the rotary compressors along with the centrifugal compressors that allowed them to work together. We also helped with the plant’s demand-side integration. The system automatically calculated the projected demand based upon which conveyors were being used.

The results were astounding. They found in a study after Case Controls finished the upgrades that the improvements generated an overall savings of more than $111,000 in the first year. The company also found that, due to the improvements that were made, the operators who work in the plant are now more aware of how to manage the compressed air necessary for the conveyance systems, resulting in an overall increase in efficiency.

Case Controls can help your company save money and improve your operations, as well. We offer a wide range of control solutions to manage air compressors at industrial facilities and can help assess your operation and help you find increased efficiency. Learn more by calling us today at 812-422-2422.