Tag Archives: Compressed Air Systems

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.

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.