compressor safety valve leaking free sample

You may not worry often, if at all, about whether or not your air compressor is running safely. And you really don’t have to, because compressor manufacturers do. From the pressure rating on the air storage tank to emergency stop buttons, air compressors are designed with safety in mind.

But that doesn’t mean you should never think about your compressor’s safety features. In most cases, they need to be inspected regularly to make sure they’re working properly. One key safety feature that should be inspected regularly is the air pressure relief valve (PRV), sometimes called a safety relief valve.

The pressure relief valve is a safety valve that protects the compressor component that it’s attached to from being exposed to a pressure above its rated maximum operating pressure. This rating, called the maximum working pressure (MWP), is the pressure that the vessel has been certified to continuously operate at safely.

So when a compressor is running at or below its maximum working pressure—in other words, when it’s running “normally”—the relief valve doesn’t do anything.

However, when the air pressure inside a compressor exceeds its MWP, the pressure relief valve will activate to “blow off” the excessive pressure within the compressor. Without a relief valve, the storage tank could rupture from the excessive pressure, damaging the compressor itself, possibly other property near it, and even causing injuries (or worse) to anyone standing nearby.

Before we can talk about how the air pressure relief valve works, we first need to look at how air pressure inside a compressor is managed when everything is running normally.

Under normal circumstances, the air pressure in a compressor is controlled by a pressure switch in an electro/mechanical control system or, in the case of an electronic controller, a pressure transducer and controller settings. When the cut-out set pressure for the pressure switch is reached, the compressor will stop compressing air (unload) until the cut-in set pressure is reached, at which time it will start compressing air again (load). If the pressure switch fails, the compressor would not be able to start compressing air again, or potentially worse, not be able to stop. Most compressors also have a high-pressure safety switch that should stop the compressor if the pressure exceeds the unload set point.

A pressure relief valve is a straightforward safety backup to the pressure switch and high-pressure switch, or the controller set points, should any of these components fail with the compressor running. The safety relief valve is set above the high-pressure safety switch and generally at or below the vessel’s maximum operating pressure. Inside the valve is a spring, and the pressure created by the spring’s tension keeps the valve closed under normal operating conditions. However, as the air pressure increases in pressure vessels (like the storage tank), it eventually exceeds the rated pressure of the relief valve, causing the relief valve to open and the excess pressure to be “blown off” to the atmosphere.

If the pressure relief valve fails open, air will continually vent to the atmosphere, preventing the air stream from becoming fully pressurized. The compressor should be shut down and the relief valve replaced before the compressor is restarted. The open relief valve will likely cause a loss of production and possible danger to personnel as a result of the flow of high-pressure air with flying debris and an unsafe sound level.

A pressure relief valve failing closed presents a potentially more dangerous situation. As noted earlier, the relief valve exists to allow excessive pressure to be “blown off” so that the air pressure inside the compressor’s pressure vessels don’t exceed their rated specifications. If the valve fails closed, this pressure venting can’t happen. Unless compressed air demand matches the compressed air supply, the pressure inside the compressor will continue to build. Eventually, the pressure increase would cause the storage tank to rupture, damaging the compressor and possibly causing additional damage and injury to property and people nearby.

If the relief valve is opening because the air pressure in the compressor has exceeded the valve’s pressure set point, that means the valve is working and doing what it was designed to do. But because this indicates the MWP of the compressor has been exceeded, the condition that’s causing excessive pressure should be diagnosed and corrected.

If the relief valve opening wasn’t caused by excessive pressure inside the compressor, then the valve is most likely “failing open”. Most likely, this is because the valve has become “soft” over time, i.e. the valve spring is providing less counterpressure, so it’s opening at a lower pressure than it should.

Whether the valve opened because of excessive pressure in the compressor or because the valve is failing, you should have your local air compressor distributor inspect your compressor before running it again for two reasons:

First, your distributor can determine whether the valve opened due to a failing relief valve or excessive compressors pressure and perform any needed maintenance or service to get your compressor running efficiently and safely again.

Second, regardless of why the pressure relief valve opened, replacing it may be recommended to ensure safe compressor operation, depending on the valve manufacturer. (Replacement is recommended for Sullair compressors.)

Important: Running the compressor after the relief valve has opened, regardless of the reason why it opened, can put both your property at risk of damage and people at risk of injury (or worse). While this may be obvious if the compressor is building up excess pressure, it also applies if the valve failed open. As noted above, even a valve that fails open poses some risk, and next time it could fail closed.

Given how critical a working air pressure relief valve is to the safe and efficient operation of your air compressor, you may wonder whether you need to do any regular inspecting or testing of the valve to make sure it is working. Because this can vary by manufacturer, you should consult your owner’s manual or contact your local air compressor distributor for frequency and type of inspection needed. For most Sullair compressors, inspection for damage or leakage is recommended, but testing is not recommended, as doing so may compromise the valve’s performance.

However, one thing you should do is schedule regular maintenance with your local air compressor distributor. As part of regular maintenance, a service technician can inspect the PRV and let you know it’s at an age or in a condition at which the manufacturer recommends replacement. Also, problems with the compressor’s performance, e.g. not reaching normal operating pressure, may help the service technician identify a failing relief valve after ruling out other possible causes.

When a pressure vessel like a receiver, sump tank or other storage vessel is purchased separately from the compressor, it may not be supplied with a pressure relief valve. To ensure its safe operation, you should add a PRV.

When selecting a PRV to add to the pressure vessel, you must choose a valve with a pressure set point set at or below the maximum working pressure of the vessel. You will find the MWP (and other useful information) on a tag welded to the pressure vessel. Also, flow capacity of the PRV must meet or exceed the total compressed air supplied to the vessel.

For example, if you have two compressors with capacities of 500 and 750 cfm (14.2 and 21.2 m³/min), and a pressure vessel with a maximum working pressure of 200 psi (13.8 bar), the minimum settings for a pressure relief valve would be 1250 cfm (35.4 m³/min) and a set point 200 psi (13.8 bar) or less.

Finally, when attaching the valve to the vessel, the porting must not be reduced to a size less than the size of the inlet port of the pressure relief valve.

Because the pressure relief valve is critical to the safe operation of your compressed air system, if you’re not sure how to select the correct PRV and properly and safely add it to the pressure vessel, contact your local air compressor distributor. They have the experience and expertise to ensure that the PRV is sized and installed correctly.

If the tank is over pressurized, the pressure switch isn"t shutting off the motor when the air tank fills to the cut-out pressure. Move the pressure switch lever to the off position. If the compressor continues to run, replace the pressure switch, because the switch isn"t shutting off the compressor motor.

If the compressor shuts off when you move the pressure switch lever to the off position, pull the safety valve ring and release all air from the tank. Switch the pressure switch lever to the on position and allow the tank to fill. If the compressor doesn"t shut off when the air tank fills to the cut-out pressure, replace the pressure switch, because the switch isn"t shutting off the compressor motor when tank pressure reaches the cut-out pressure.

An air compressor problem could stem from one of many issues, such as an air leak, an oil leak or a broken part. In some cases, you might have insufficient pressurization or air flow. In other cases, the compressor might fail to start up or stop running as prompted. Whatever the cause of the problem, the symptoms can be frustrating, costly and time-consuming.

Thankfully, most such problems can be corrected with proper air compressor troubleshooting. The Titus Company has developed this troubleshooting guide for reference when your air compressor won’t work. Whether you’re hearing excessive noise from your portable air compressor or your system won’t build pressure, you’ll find the cause here — and, hopefully, a solution. If not, call us. We’ll be there quickly with our 24/7 emergency services.

Good air pressure is essential to a well-powered machine. When air is leaking from your tank or hoses, you’ll notice low pressure, which brings on extra time and energy costs that can leave your business behind. An air leak could be down to one of several factors. Fortunately, leaks can be sealed with the right kind of air compressor troubleshooting. The following symptoms are among the most common leak-related air compressor problems:

If you shut off the air compressor on full charge, yet the gauge drops while the compressor is deactivated, you definitely have an air leak. The compressor might even automatically restart just to counter the situation. What you need to do in this situation is pinpoint the source of the leak.

Apply soap to the connections: With the compressor unplugged, cover the connections with liquid soap, including all the couplers and the pressure switch. If bubbles form at any point, that is where the leak is located. Tighten up the coupler, if possible, where the bubbling occurs.

Inspect the tank check valve: Air leaks are sometimes caused by tank check valves that fail to close completely. If the pressure gauge continues to drop when the tank is off, access the tank valve and inspect its condition. The valve might need to be cleaned or replaced.

If the air leaks occur only when a hose is plugged into the compressor, disconnect the hose. If the pressure gauge stops dropping, the hose is the source of your leak.

If your compressor is losing pressure through the oil fill tube, check the piston seals. In most such cases, the piston seals will be badly worn and in need of immediate replacement. This is a problem that you should remedy immediately, as worn pistons can cause metal-on-metal friction that could swiftly lead to internal corrosion.

Air leaks from under the hood are sometimes encountered on smaller air compressors. To diagnose the problem, remove the hood, run the compressor for a few minutes, then shut it off and unplug the compressor. Feel around the motor parts for any sort of air draft. Chances are, the leak will originate from the tank valve, in which case you will need to remove and clean or possibly replace the valve.

If you notice an electrical issue, you need to take a look at it or have a professional come out as soon as possible. It could be anything from your motor capacitors to misfiring piston rings. If the power cuts out on your air compressor — or the power is insufficient and unreliable — the problem is most likely down to one of the following factors:

Extension cords: If your compressor is connected to an outlet via an extension cord, the motor could be deprived of sufficient energy, causing the motor to overheat. Compressors are not like home electronics, which can suffice on extension cords and power bars. An air compressor should only be powered through a direct connection to a power source.

An old motor: If your compressor has run on the same motor for many years, it could be time for a change-out. An older motor is liable to have worn windings, loose capacitor wires and other general wear that could easily result in blown fuses and breakers.

An air compressor consumes massive volumes of power at the time of startup. This is known as the inrush, which vastly exceeds the amount of power generally consumed throughout the rest of a usage cycle. To prevent fuses from breaking during this inrush, compressor motors are equipped with starter capacitors, which manage the incoming power. A dimming light is one of the tell-tale signs that the starter capacitor is worn and due for a replacement.

If your air compressor trips off the moment it powers on, the issue is likely caused by trapped air over the pistons. To test for this problem, shut off the tank, unplug it from the power supply and drain the tank of all air. This should relieve the pistons of undue air pressure and allow the tank to start without further issues. Trapped air over the pistons is usually caused by a faulty unloader valve, which should be inspected, cleaned and possibly replaced if the issue persists.

When an air compressor fails to start up, shut down or provide any degree of air pressure while active, the problem could be down to one of several issues. Each case should be taken on its own, as follows:

Aside from the obvious oversights such as a disconnected power cord or a deactivated power switch, a compressor will typically fail to start when it lacks sufficient air pressure. If the cut-in pressure is not proportional to the amount of air pressure stored in the tank, the compressor will often fail to start. Check the cut-in setting on the pressure switch and adjust the level accordingly.

The compressor should stop once the tank pressure drops to the cutoff point. If this fails to occur, the problem will generally be down to one of two issues:

Faulty pressure release valve: If the valve fails to release pressure, the tank will be too pressurized for the motor to stop running. In cases like these, you should cut the power and refrain from further use until the valve is replaced, as further use could seriously damage the compressor.

Faulty pump: If the motor is running and making noise yet no air comes out, you probably have a faulty air-intake pump that needs to be replaced. As long as the compressor is not too hot, you can feel for lack of pump pressure manually with a pair of protective gloves.

Faulty gasket: If the compressor only generates small amounts of pressure, there might be an issue with the gasket between the low-pressure and high-pressure compartments of the compressor, such as air flowing from one side to the other without sufficient pressurization.

Fortunately, pumps and gaskets can easily be changed out. With a simple parts replacement, you should be able to get many more years of performance from the compressor at hand.

If compressor oil works its way into the air lines, the effects could be detrimental elsewhere in the compressor because the pump uses a different kind of lubricant than other parts of the system. Once inside the air lines, that oil will be dispersed to other areas, potentially causing seals to crack or swell. Oily air lines are most troubling when the oil travels to plastic parts of the air valve.

In a reciprocating air compressor, the oil must first travel past the piston seals to make its way to the tank. When this occurs, the seals should be replaced immediately. This would also be an opportune time to replace the valve and gasket.

When removing the oil, take a look at it and ensure it appears clear and consistent. Sometimes, you may notice your oil has a milky look to it — this happens when your air compressor is exposed to excessive humidity and condensation has gotten into the oil reservoir. In this case, you should drain and replace the oil and move your air intake pipe to a less humid environment.

If you experience these problems, remove the filter housing from the intake pump and run the compressor again. If the problems cease and the compressor runs normally, the issue is rooted in the air intake media. From here, you have two options — cleaning or replacing. To clean a compressor filter, run water through it until you don’t see any dirt particles.

If an air compressor seems to have stopped working due to a broken part, you first need to test the part to verify the root of the problem. A compressor will not work if the following parts are broken. Fortunately, all can be replaced:

The intake filter is a crucial part of the air compressor because it strains impure particulates from the incoming air. Since it physically sticks out from the rest of the unit, an intake filter is one of the more easily broken parts to an air compressor. Fortunately, it is also one of the easier parts to replace. As long as you find a filter with the same thread size and roughly the same portal size and diameter, it should work for your machine.

If you break the pressure switch on an air compressor, you might be surprised by the underlying complexities. Fact is, any old replacement switch will not solve the problem due to all the connecting points of the manifold. To fix the problem, you will need to find a switch that accommodates each of the four or five connecting points, which will generally include sockets for the pressure relief valve, the air tank gauge, the compressor tank and the quick coupling.

Before you buy a new pressure switch and manifold, take note of the following details on the old switch, each of which must be matched on any new switch you attach to the compressor:

Many newer air compressors — particularly those on the lower-cost end of the spectrum — blow air with fans made of plastic, which is less expensive than metal but is also more easily prone to wear and tear. Fortunately, a replacement fan made of either material will work in almost any compressor. Therefore, if you have a fan with broken plastic blades, you could turn this into an opportunity to upgrade to metal.

Before you pick a replacement fan, check the compressor manual for a listing of the part number and corresponding dimensions. If not found, measure the dimensions and the hole diameter of the original fan. Take note of the number of blades and the direction of airflow, as both details are consequential to the performance and make of the compressor.

If the motor of your air compressor fails to power on when you flip the switch, it could be a matter of the switch itself, though you should run some tests before you draw any conclusions. Check the power cord to ensure that it is plugged into a functioning socket. If the power switch still fails to activate the compressor, plug a light or electronic device into the outlet to see if that powers on.

If the outlet works for other devices but not your compressor, pull back the housing that confines the switch, remove it from the socket and check the compressor owner’s manual for specs on the switch. Make sure that your replacement switch will match the specs and fit the socket.

Air compressors serve all kinds of purposes on a professional as well as personal scale. From pressing plants and factories to repair shops and studios, pressurized air is used to assemble everything from automobiles and aircraft to appliances and home furnishings. Today’s compressors are designed to deliver optimal power with sleek designs through many usage cycles.

At The Titus Company, we offer maintenance on a variety of air compressor types and brands. Contact us today to learn more about our products and services and how we can help you fix an air compressor that won’t work as intended.

A little product education can make you look super smart to customers, which usually means more orders for everything you sell. Here’s a few things to keep in mind about safety valves, so your customers will think you’re a genius.

A safety valve is required on anything that has pressure on it. It can be a boiler (high- or low-pressure), a compressor, heat exchanger, economizer, any pressure vessel, deaerator tank, sterilizer, after a reducing valve, etc.

There are four main types of safety valves: conventional, bellows, pilot-operated, and temperature and pressure. For this column, we will deal with conventional valves.

A safety valve is a simple but delicate device. It’s just two pieces of metal squeezed together by a spring. It is passive because it just sits there waiting for system pressure to rise. If everything else in the system works correctly, then the safety valve will never go off.

A safety valve is NOT 100% tight up to the set pressure. This is VERY important. A safety valve functions a little like a tea kettle. As the temperature rises in the kettle, it starts to hiss and spit when the water is almost at a boil. A safety valve functions the same way but with pressure not temperature. The set pressure must be at least 10% above the operating pressure or 5 psig, whichever is greater. So, if a system is operating at 25 psig, then the minimum set pressure of the safety valve would be 30 psig.

Most valve manufacturers prefer a 10 psig differential just so the customer has fewer problems. If a valve is positioned after a reducing valve, find out the max pressure that the equipment downstream can handle. If it can handle 40 psig, then set the valve at 40. If the customer is operating at 100 psig, then 110 would be the minimum. If the max pressure in this case is 150, then set it at 150. The equipment is still protected and they won’t have as many problems with the safety valve.

Here’s another reason the safety valve is set higher than the operating pressure: When it relieves, it needs room to shut off. This is called BLOWDOWN. In a steam and air valve there is at least one if not two adjusting rings to help control blowdown. They are adjusted to shut the valve off when the pressure subsides to 6% below the set pressure. There are variations to 6% but for our purposes it is good enough. So, if you operate a boiler at 100 psig and you set the safety valve at 105, it will probably leak. But if it didn’t, the blowdown would be set at 99, and the valve would never shut off because the operating pressure would be greater than the blowdown.

All safety valves that are on steam or air are required by code to have a test lever. It can be a plain open lever or a completely enclosed packed lever.

Safety valves are sized by flow rate not by pipe size. If a customer wants a 12″ safety valve, ask them the flow rate and the pressure setting. It will probably turn out that they need an 8×10 instead of a 12×16. Safety valves are not like gate valves. If you have a 12″ line, you put in a 12″ gate valve. If safety valves are sized too large, they will not function correctly. They will chatter and beat themselves to death.

Safety valves need to be selected for the worst possible scenario. If you are sizing a pressure reducing station that has 150 psig steam being reduced to 10 psig, you need a safety valve that is rated for 150 psig even though it is set at 15. You can’t put a 15 psig low-pressure boiler valve after the reducing valve because the body of the valve must to be able to handle the 150 psig of steam in case the reducing valve fails.

The seating surface in a safety valve is surprisingly small. In a 3×4 valve, the seating surface is 1/8″ wide and 5″ around. All it takes is one pop with a piece of debris going through and it can leak. Here’s an example: Folgers had a plant in downtown Kansas City that had a 6×8 DISCONTINUED Consolidated 1411Q set at 15 psig. The valve was probably 70 years old. We repaired it, but it leaked when plant maintenance put it back on. It was after a reducing valve, and I asked him if he played with the reducing valve and brought the pressure up to pop the safety valve. He said no, but I didn’t believe him. I told him the valve didn’t leak when it left our shop and to send it back.

If there is a problem with a safety valve, 99% of the time it is not the safety valve or the company that set it. There may be other reasons that the pressure is rising in the system before the safety valve. Some ethanol plants have a problem on starting up their boilers. The valves are set at 150 and they operate at 120 but at startup the pressure gets away from them and there is a spike, which creates enough pressure to cause a leak until things get under control.

If your customer is complaining that the valve is leaking, ask questions before a replacement is sent out. What is the operating pressure below the safety valve? If it is too close to the set pressure then they have to lower their operating pressure or raise the set pressure on the safety valve.

Is the valve installed in a vertical position? If it is on a 45-degree angle, horizontal, or upside down then it needs to be corrected. I have heard of two valves that were upside down in my 47 years. One was on a steam tractor and the other one was on a high-pressure compressor station in the New Mexico desert. He bought a 1/4″ valve set at 5,000 psig. On the outlet side, he left the end cap in the outlet and put a pin hole in it so he could hear if it was leaking or not. He hit the switch and when it got up to 3,500 psig the end cap came flying out like a missile past his nose. I told him to turn that sucker in the right direction and he shouldn’t have any problems. I never heard from him so I guess it worked.

If the set pressure is correct, and the valve is vertical, ask if the outlet piping is supported by something other than the safety valve. If they don’t have pipe hangers or a wall or something to keep the stress off the safety valve, it will leak.

There was a plant in Springfield, Mo. that couldn’t start up because a 2″ valve was leaking on a tank. It was set at 750 psig, and the factory replaced it 5 times. We are not going to replace any valves until certain questions are answered. I was called to solve the problem. The operating pressure was 450 so that wasn’t the problem. It was in a vertical position so we moved on to the piping. You could tell the guy was on his cell phone when I asked if there was any piping on the outlet. He said while looking at the installation that he had a 2″ line coming out into a 2×3 connection going up a story into a 3×4 connection and going up another story. I asked him if there was any support for this mess, and he hung up the phone. He didn’t say thank you, goodbye, or send me a Christmas present.

Valve leakage is a common but troublesome occurrence in industrial facilities. While some valves are expected to have a certain level of leakage, especially as they begin to reach nameplate set pressure, other valve leakage is problematic and can even be dangerous for your facility. If you suspect valve leakage, here are a few reasons why your safety or pressure relief valve may be leaking, how to test the valve, and how to troubleshoot a valve you’ve confirmed is leaking. Four common reasons a pressure relief valve might be leaking include:

Pressure relief and safety relief valves will leak if the valve isn’t fully closed. This is a common problem in industrial settings where environments are often dusty or dirty. If there is any debris in the valve, it can obstruct the valve from fully closing, causing it to leak.

Pressure relief valves age and can begin to deteriorate, especially in factories and facilities where they encounter extreme temperatures and a great deal of wear. Over time, valves can become damaged, which affects their ability to close properly. If there is any damage or excessive wear to the valve seat or seal, leakage is likely.

Another common cause of safety relief valve leakage is when the valve is the wrong size for the project. Whether it’s a loose fit or the wrong fit entirely, a poorly fitting valve won’t be able to function properly, and will often leak.

If you suspect a leaking safety relief valve, or if you would like to complete regular maintenance to prevent valve leakage in the first place, it’s good to know that it is possible to test for a leaking valve. Known as a seat tightness or leakage test, these tests maintain the pressure relief valve’s inlet pressure at a certain percentage of the valve’s set pressure, so the valve technician can assess the valve’s condition.

The AccuTEST inline valve testing system offers a unique feature —  the Lift and Hold test — specifically designed to test for leakage. The system performs an automated leakage test according to the operator’s requirements. The operator sets the percent of set pressure and the duration of the test. When the operator starts the test, the AccuTEST system takes over, holding the valve at the appointed percentage of set pressure for the specified duration. While the system holds the valve at pressure, the operator is able to count any bubbles in the valve to assess its condition and determine whether the valve is leaking or not.

When you have confirmed the source of the leak, you can assess whether the valve could be repaired, or if it should be completely replaced. For example, if the valve is the wrong size or if the valve is damaged, it’s best to replace it. If the valve can be cleaned and adjusted to function properly, then repair may be an option.

Once your leaking safety relief valve has been repaired or replaced and is functioning as it should, it’s important to consider implementing regular maintenance and testing. Leaking pressure relief valves can present serious complications for the functionality of your facility. Implementing a regular maintenance and pressure relief valve testing schedule can help you stay in front of concerns like this, ensuring your facility is running efficiently, and at pressure, at all times.

If you are concerned about a leaking safety or pressure relief valve, or are seeking inline valve testing equipment that is capable of performing seat tightness or leakage tests, you might be interested in AccuTEST’s equipment. With exclusive Lift and Hold testing capabilities, AccuTEST inline pressure relief valve testing equipment offers the functionality you need. See how our equipment works in real-time — schedule a live webinar demo today.

Your pressure relief valves are the most important pieces of safety equipment in your facility or along your pipelinesystem. There’s no margin for error. Your PRVs need to work — every time. So how do you know when you can get by with a repair, or when it’s time to replace them?

In many cases, regular valve testing and repair isn’t optional. It’s mandatory. But how do you know if it’s time for a replacement? Here are three times you need to think about repairing or replacing your pressure relief valves.

Pressure relief valves are designed to open to relieve pressure in your system and then close again. In a clean environment, they may be able to open and close multiple times with no problems. But, in some cases, when a valve opens, debriscan get into the valve seat, which can prevent the valve from returning to its originalclosed position.

In some locations and industries, regulations govern how long valves are allowed to be in operation before they need to be repaired or replaced. For example, your state inspector may require that your valves be completely disassembled, inspected, repaired, and tested every five years. In extreme cases, such as if a valve is frozen, the local jurisdiction will mandate replacement.

For smaller valves and applications, you can test your valve by lifting the test lever. Note, though, thatyou shouldn’t do this too often, only about once a year.ASME UG136A Section 3 requires valves have at a minimum of 75% operating pressure versus the set pressure of the valve for hand lifting to be performed.

For larger valves and applications, you can send them to us for testing or we can visit your facility and test them online through ourElectronic Valve Testing (EVT) services.

The service and application a valve is used for affects its longevity. A valve used for clean service, such as steam, can last a long time — easily 20 years if it isn’t operated too close to the set point and gets the right preventative maintenance program. On the other hand, a valve that used for acid service, operated too close to the set point, or exposed to dirt or debris in the system will need to be replaced more often — such as every 10 years.

Our technicians are factory-trained to repair and recertify valves back to their OEM specifications. But is that the best course of action? Or should you just replace them?

In general, we recommend repairing your valves when possible to get the most out of your investment. However, sometimes, replacement is simply more cost-effective than repair.

In either case, it will certainly cost less to replace the valve than to pay for any damage you might incur from keeping it in service past its prime!

In general, it’s difficult to impossible to say exactly how long your pressure relief valves will last. It depends on several factors, including the service, the system, and how the valves are operated. The best way to both keep your valves operating correctly and identify when they need to be replaced is to put them on a regular preventative maintenance program, ideally supported by a valve management software like ValvKeep.

At Allied Valve, your safety is our first priority. Our pressure relief valve repair services can keep your valves working at their highest levels of performance.Learn more about what we can do for you.

Conventionally when we talk about oil lubricated screw air compressor maintenance, it is mostly about replacing consumables such as filters and lubricant on time. While these consumables have a defined usable life and have a direct effect on the efficiency and the life of the air compressor itself when not replaced on time, there are a few critical valves in the air compressor that require maintenance as well. Compressor valves directly affect the efficiency, safety, and the functionality of the screw air compressor. Let us understand some of the commonly available valves in a screw air compressor, why they need maintenance, and discuss some of the frequently asked questions about screw air compressor valves.

A screw air compressor is very similar to a human heart. While a human heart has tricuspid, pulmonary, mitral, and aortic valves, a screw air compressor has four critical valves namely air inlet, minimum pressure, blow down, and safety valves.

Air inlet valve is also commonly known as the ‘Intake valve’ which is typically assembled on the airend’s intake. The air inlet valve of a conventional fixed speed screw air compressor controls the air intake into the compressor. It remains closed when the compressor starts to lower the starting load on the main motor and when the desired working pressure is attained in the compressed air circuit and thus enabling the compressor’s motor to run without any load. In some compressors that are capable of providing a variable output by modulating the amount of air it sucks in, the inlet valve holds various opening positions to regulate the volume of air entering the compressor. The effective performance of the inlet valve directly affects the compressor’s capacity and its power consumption during load and no-load conditions.

The minimum pressure valve is typically assembled on the exit of the air-oil separation tank of a compressor. The minimum pressure valve acts as a check valve preventing back flow of compressed air into the airend, retains a minimum pressure in the compressor system for lubrication, offers a restriction to avoid a collapse of the air-oil separation filter, and ensures a suitable velocity of flow across the air-oil separator that ensures efficient air-oil separation. The effective performance of the minimum pressure valve directly affects the compressor’s lubrication, air-oil separation efficiency, and power consumption during load and no-load conditions.

The blow down valve is typically found on a dedicated exhaust line from the air-oil separation tank. The blow down valve evacuates the compressed air in the air-oil separation tank each time the compressor runs on a no-load and when the compressor shuts down to ensure there is no back pressure when the compressor starts to load next time. The blow down valve of a conventional screw compressor is typically actuated by a solenoid valve. The effective performance of the blow down valve affects the compressor’s power consumption during un-load, capacity of the compressor when running on load, and the life of the motor.

The safety valve is typically mounted directly on the air-oil separator tank. The only function of the safety valve is to blow off the compressed air in the air-oil separation tank when the pressure in the air-oil separation tank exceeds the set pressure of the safety valve and there by prevents the tank from cracking under high pressure. A malfunctioning safety valve affects the safe operation of the air compressor or results in leakage of compressed air continuously.

Though each compressor manufacturer has their own unique valve design, compressor valves in general contain moving parts such as springs, valve plates, and plungers that affect the opening and closing of the valves and rubber seals / seats that offer perfect sealing when the valves remain closed. These moving parts wear or lose their mechanical properties over a period of time and the sealing components typically ‘age’ over time and lose their effectiveness and will need to be replaced.

Compressor manufacturers typically design these components to operate efficiently for several thousand or millions of operation cycles. However, several factors such as variability in the demand pattern, sizing of the air compressor against a certain air demand, the environment in which the air compressor operates, promptness of preventive maintenance, etc. determine how long these valves efficiently operate.

Many times, it is difficult to identify a malfunctioning valve or a valve operating with worn-out parts as the compressor continues to generate air. The typical symptoms of a malfunctioning valve are loss in compressor"s capacity, increase in power consumption during load or/and unload, drop in discharge pressure, increase in oil carry-over and more load on motor. These symptoms are either difficult to notice or have other frequently common assignable causes such as air leak before suspecting the compressor valves.

Case studies show that operating a screw air compressor with a worn-out / malfunctioning valve could increase its overall power consumption by 10 - 15%. Power cost contributes to more than 75% of the compressor’s total life cycle cost over ten years and hence this is a significant impact. Unserviced valves also lower the life span of downstream accessories by half. In some cases, a malfunctioning safety valve may result in a catastrophe.

Air compressor manufacturers typically offer convenient valve maintenance kits for customers that contain the internal parts of the valve that wear or age out. Changing the valve kits is a much more sensible and economical option than changing the complete valve.

It is difficult or almost impossible to identify a malfunctioning valve unless it is opened for inspection. Hence it is absolutely mandatory that these valves are inspected for effectiveness every year and the internal moving parts replaced as a part of preventive maintenance once every year or two depending on the operating conditions of the air compressor. It is typical for compressor manufacturers to mandate a valve kit replacement once every two years as a proactive measure.

In particular, the safety valve must be inspected and certified every year per the local safety laws to ensure they are functional and efficient. Sometimes, replacing the safety valve entirely with a valid certificate for one year is more economical as the certification procedures could be equally expensive on an existing valve.

As stated before, it is challenging to identify a valve that is worn out unless it is opened and inspected, but there are a few indicators that a qualified compressor technician can use to deduct a malfunctioning valve.

Low duty cycle operation: A sophisticated screw air compressor in today’s day and age carries a convenient microprocessor-based human-machine interface that keeps track of operating hours of the compressor under load and un-load conditions and the number of load/unload counts the compressor is subjected to over a period of time. A higher un-load hours and load/unload count indicates that the air compressor is oversized against the actual air demand. This in turn indicates the air compressor ‘cycles’ frequently between load and un-load mode as opposed to running continuously on load. Every time a compressor ‘cycles’, the inlet valve, blow down valve, and minimum pressure valve is brought into play where their internals ‘actuate’. Frequent actuation of these valves results in a faster wear of the internals and hence results in shorter life.

High operating temperature: A compressor that runs on a high operating temperature affects the life of the valve’s sealing components, which causes them to ‘age’ fast.

Compressor not building pressure: If the air demand has not changed over time and the facility is relatively free of any air leakage, the air compressor is probably not delivering the rated output. There is a high probability that there is a malfunctioning valve.

Increase in compressor’s power consumption: An increase in the air compressor’s power consumption profile over a period of time where there has been no abnormal change in the air demand and usage pattern indicates an increase in either the load or un-load power. There is a high probability that this is because of a malfunctioning valve.

Based on the design philosophy adopted by the air compressor manufacturer, the oil lubricated screw air compressors could have a few more valves that are critical to functional performance that must be maintained as well. Some of the other valves frequently used in an air compressor are as follows:

Temperature control valve (also known as thermal valve) is used to regulate the flow of oil through the oil cooler based on the operating temperature.

Drain valves are used to drain lubricant at the time of lubricant change over or cleaning. Air compressors equipped with a moisture trap at the outlet of the after cooler also has a drain valve (automatic or timer based) to discharge water collected.

The presence or absence of one of these valves and the type of actuation of these valves (electronic / mechanical) depends on air compressor’s design architecture. The Operation and Maintenance Manual (OMM) and the Piping and Instrumentation Diagram (P&ID) supplied by the air compressor manufacturer are excellent resources that explain the purpose, functioning, and maintenance requirements of these valves.

Many of the air compressor valves are highly specialized and exclusive. Their designs are usually complex and some even need special tools to service them. The internal components" build quality and material selection are extremely important and proprietary. Hence it is highly critical that only genuine valve kits issued by the air compressor manufacturer are used to maintain the valves. An inferior after-market replacement will most certainly compromise the performance of the entire compressor, void the original manufacturer"s warranty of the compressor, cause consequential damage to other parts of the compressor, and above all, be a safety hazard.

In conclusion, while it is important to change the screw air compressor"s filters and lubricants on time, it is equally important to perform preventive maintenance on these critical valves in a screw air compressor as recommended by the air compressor manufacturer. While the intake valve, minimum pressure valve, safety valve, and blowdown valve are critical to the performance and safety of the compressor, there could be other valves in the compressor that are critical and need maintenance. The air compressors sizing and the environment in which it operates are crucial factors that affect the life of the air compressor. Finally, it is critical to proactively service these valves using genuine kits issued by the compressor manufacturer to enable the air compressor performs efficiently and safely.

ELGi North America, headquartered in Charlotte, NC, is a subsidiary of ELGi Equipments Limited, a leader in compressed air solutions for over 60 years. Established in 2012, ELGi North America, in conjunction with its subsidiaries, Pattons, Pattons Medical, and Michigan Air Solutions, offers a comprehensive range of compressed air products and services. Our product offering includes oil-lubricated and oil-free rotary screw and reciprocating compressors, dryers, filters, and ancillary accessories. ELGi and its subsidiaries serve multiple industry verticals spanning medical applications, pharmaceuticals, food & beverage, construction, manufacturing, and infrastructure. For more information, visit https://www.elgi.com/us/.

Not sure on 13D/13R systems but if memory serves me existing sprinkler systems are allowed to leak 3PSI every 2 hours on commercial installations. Running 3-4 minutes every 3 hours doesn"t seem like a very long run time or frequency for that matter. That"s running for a culmitive of 32 minutes a day across 8 separate on/off cycles. If you know the capacity of the sprinkler system and the supervisory pressure you can calculate the allowable leak rate and make the judgement if a repair is needed. Typically riser mounted air compressors are sized volumetrically for system capacity (in gallons). If undersized the run times can get extended. If indeed a riser mounted compressor then it"s likely an oil free compressor and oil free compressors are typically loud by most comparison. With all that said, the Quiet Series (I assume you"re talking about the Q-Series by GAP) are very quiet. Almost unnoticeable if you"re in the same room with it. Sounds more like the volume is complaint not the frequency or run time.

Safety should be the priority in any workplace environment, whether it’s a construction site, a factory or another setting. Business leaders want to make sure their employees are safe, maintain high morale among their workforce and reduce the possibility of damaged or broken machinery. By employing practical safety measures, your company can benefit from increased uptime and fewer repair or replacement expenses.

Having safety measures in place is especially important when working with air compressors and other high-powered machinery. Compressed air should be treated with the same amount of care as other energy sources, as misuse or a lack of the proper precautions can present risks. It’s essential that all operators have the proper training, have read all instruction manuals thoroughly and understand how to mitigate safety risks and potential damage. Manuals contain an abundance of valuable information and will tell you how to keep your compressors running for longer periods without damage or injury.

There are also plenty of other resources that discuss how to maintain safety when operating pneumatic tools and air compressors. This guide will take you through the basics of using an air compressor, what to check before use, what to monitor and how to keep operators and workspaces safe to minimize air compressor dangers.

Air compressors are useful for many jobs, but they can also become dangerous when not maintained properly or misused. Compressor machines, hoses, pneumatic tools and electric connections can all pose hazards in the workplace. Air compressor accidents could potentially cause harm to workers and machinery.

What are some of the most common hazards related to air compressors? They include electrical dangers, fumes, flying particles, high pressures and high noise levels.

Operators and workers can mitigate these dangers by following proper safety measures and air compressor precautions, which we will discuss later in the guide.

Depending on where you’re working, the intake air can contain pollutants and contaminants that are harmful to your health. From carbon monoxide to dust and debris, the air in the compressor collects from the surrounding space. To keep yourself safe while using the compressor unit, you must work in an area with proper airflow or natural air access, as well as protective gear, such as a respirator or dust mask.

While the likelihood of a workplace fatality due to an air compressor failure is low, it can happen in some extreme circumstances. If a compressor tank explodes, it can endanger your workers’ lives, but typically, the highest amount of danger lies with the operator. Due to the high pressures and pneumatic tools attached, operators must abide by all safety rules and regulations, including having the proper protective gear.

Every operator needs to undergo proper training and learn the relevant safety standards before using an air compressor. If you upgrade your air compressors or make any repairs, it’s essential to update operators on any changes so they know how to use the machine correctly and know what to look out for. It’s also important to check air compressor safety regulations from the Occupational Safety and Health Administration (OSHA) and ensure you’re in compliance with any that apply to your uses or machines.

The way your equipment and workspace are set up can have a significant impact on safety. Some air compressor and workspace setup tips to keep in mind include:

Component pressure ratings: Make sure that all components, including hoses, pipes and fittings, are rated for the maximum pressure of the air compressor.

Relief valves: Relief valves automatically release air if the pressure in the tank gets too high. These valves are important air compressor tank safety features, so you should never attempt to adjust, bypass or remove them.

Drain valves: If your compressor has an electric drain valve, make sure it is at least a foot and a half above the ground. Electric drain valves must be kept away from moisture.

Workspace humidity: It’s important to keep the humidity in your workspace from getting too high. To decrease the moisture in the air, try increasing air circulation in the workspace, operating your compressor for longer periods, using a peripheral crankcase heater or adding a dryer to your compressed air system.

Before using a compressor, you need to check various components to make sure the machine will work properly. To keep track of any issues and ensure you’ve looked at all the necessary areas, create an air compressor safety checklist for your operators to complete before each job. Some of the elements you may want to look at include:

Oil level: It’s essential to check and see if the machine has an appropriate amount of oil. Using it without an adequate amount of oil can ruin it to the point of requiring costly repairs or replacement. If it needs more oil, add oil to the reservoir but be careful not to overfill it. Also, be sure to keep oil from spilling onto the exterior of the compressor.

Fuel level:To run an air compressor, you need to have a sufficient amount of fuel. It can be a pain to have to refill in the middle of a job, as it requires you to stop, allow the compressor time to cool off and then refill the tank. Don’t refuel your air compressor when it’s on or has been shut off for only a short time. You should only conduct refuels and oil changes when the machine is cold.

Air filter:Whether you use a given compressor every day or only every once in a while, check the air filter before use. If it appears dirty or clogged, you should remove and wash it — if you have the right kind of screen — or replace it with a new filter.

Air connection:Before turning on your air compressor, make sure that it is securely connected to the air source. If the connection is weak or loose, the compressor may not perform as expected, and parts could disconnect, potentially leading to injury.

Outlets: Ensure your air compressor is only used with outlets that have the proper grounding. If you plug an air compressor into an incorrectly grounded outlet, it could damage the machine’s electrical circuitry and even cause a fire.

There are also air compression safety tips and procedures for particular parts of the compressor. Three of these components include the pressure regulation devices, air receivers and distribution lines. Each of these is significant in maintaining a healthy machine and operating it safely.

Valves:Ensure that the safety valves on your air tank are set to at least 10% or 15 psi — whichever is greater — above the operating pressure of the compressor but never higher than the air receiver’s working pressure limit. If using an air compressor in freezing temperatures, check that the safety valves are positioned in a way that prevents water from collecting inside the unit. If a valve freezes, thaw it and empty the compressor tank before reactivating the unit. The machine should also have shielded blowoff valves so sudden blowoffs don’t result in equipment damage or injury.

Air intake: The air intake should receive air only from clean, outdoor sources. Place a filter or screen at the intake valve to keep the intake air clean.

Speed: Check the manual that came with your compressor for the maximum recommended speed and ensure that you never run your compressor at speeds exceeding this level.

Draining:If your air compressor doesn’t have an automatic drain, be sure to drain the air receiver regularly so liquid does not build up inside of it.

Gauges and valves: Ensure that your air receiver has a pressure gauge and a safety valve that meets the American Society of Mechanical Engineers (ASME) standards.

Operators should also take certain precautions while operating air compressors and after completing a project using an air compressor. It’s essential to remain in control of compressor units at all times. Sound footing and standing on a level surface at a safe distance from the unit is crucial as is keeping your hands, clothing and hair away from the air nozzle and tools.

Also, be sure to wear the proper safety gear for the job. No matter what tool you’re using for a given project, it’s vital to wear protective gear for your ears and eyes at all times. According to the Center for Disease Control, an estimated 22 million workers face exposure to potentially harmful noise every year. The risks involved with failing to wear hearing guards might not always be apparent at first, but adverse effects due to exposure to noise are often experienced later, in some cases years down the line. Personal protective equipment (PPE) to consider includes goggles, face masks, rubber or leather gloves, steel-toed shoes and leather or PVC aprons. Cotton clothing is not an effective barrier to compressed air. Cover any part of the body that is at risk of coming into contact with compressed air or flying particles.

To prevent safety issues, it’s crucial to keep an eye out for any potential issues while you’re using an air compressor. Once you start the machine and begin your work, be sure to check the following items consistently:

Surroundings: In addition to managing your own safety, keep an eye out for other workers and ensure you’re keeping the surrounding area safe. Make sure that all your hoses, cables and wires are tucked away where no one can trip on them and that you keep your area clean.

Voltage:Pay close attention to your air compressor’s voltage. If repairs are needed, power down the machine, lock and tag out all power sources and release all pressure from the compressor. If your compressor is designed for indoor use, don’t use it outdoors, as rain or wet conditions can cause electrical problems.

Performing preventative maintenance is essential to keeping your compressor running smoothly and safely. It can increase the longevity of your machine and improve its capabilities. Running a clean, well-kept machine will also promote the wellbeing of your workers and operators and help manage air compressor risks.

Receive the proper training:Anyone performing maintenance on an air compressor should have received the appropriate training to ensure they conduct maintenance tasks correctly and safely.

Follow the manufacturer’s recommendations: To ensure safety in maintenance and operation, it’s important to follow the care and maintenace recommendations of your compressor’s manufacturer.

Disconnect power: Before performing maintenance work, shut off the machine and disconnect it from all power sources. Lock open the electrical switch for the compressor and tag it so no one starts it by mistake.

Clean the unit properly:Cleaning your air compressor regularly will improve its performance and extend its life. When it comes to cleaning carbon remnants from the various parts of an air compressor, it’s safe to use soapy water or a lye solution, but you should never use anything flammable, such as kerosene. Following every cleaning, completely purge the air system.

Lubricate properly:Don’t use oils with low flash points to lubricate compressor parts. These oils could combust due to the high temperatures produced by air compressors during operation. It’s essential, however, to keep parts lubricated with the proper oils and to avoid over-lubrication to prevent corrosion.

Take steps to prevent rust: One of the most dangerous possibilities when it comes to air compressors is a rusty tank. Rust increases the unit’s chances of combusting, putting anyone nearby in danger. To prevent rust due to the accumulation of liquid, use the underside valve to drain the tank daily. If a tank becomes rusted, don’t attempt to repair it. A rusted tank requires replacement.

Although proper maintenance can help extend the life of your air compressor, you may still occasionally need to troubleshoot issues. Follow these compressed air safety tips when troubleshooting your equipment:

Shut down your compressor:Turn off your compressor, disconnect it from power and bleed any remaining air pressure before doing any troubleshooting or repair work. Make sure that the shutoff valve is always within reach in case something goes wrong during operation.

Follow safety procedures for hose malfunctions:If a hose malfunctions or comes apart at the coupling, you can prevent whipping with two components. One is an air fuse of the proper size, which you should install in the hose upstream. The other is a whip-inhibiting device that is placed along the coupling of a hose. If an air hose does start whipping around uncontrollably or another similar air hose problem occurs, don’t try to stop and control it by grabbing the hose. To prevent injury, turn off the air source before touching the hose.

Use reliable parts: If a component becomes damaged or needs to be replaced for any reason, use only reliable, high-quality parts that are the correct size, material and type for your machine. Using the wrong parts or low-quality components can result in decreased compressor performance, damage to your equipment and safety hazards.

As one of the world’s leading sellers of compressed air products for nearly 100 years, Quincy Compressor offers an array of machines and parts for many industries. With our one-of-a-kind offers and round-the-clock support, we’ve supplied and serviced businesses in the automotive, manufacturing and construction sectors, among others.

People have various uses for compressed air, and at Quincy, we’ve got them all covered. With Quincy, there’s no application too demanding for our top-of-the-line products to handle with utmost ease and maximum efficiency. Everyone who shops with us receives support from our authorized partners, day or night, as well as industry-leading warranties on select compressor products.

If you’re in the market for compressed air devices or related equipment, explore our website, where you can download whitepapers for more information on our wide range of products. You can also contact your local authorized Quincy Compressor distributor for air compressor sales and service in your area.