compressor safety valve adjustment factory

I can see there are markings on the valve,but I can"t read them in situ. Once I get the new valve, I"ll read the markings on the existing valve once I have it out.

New replacement air compressor pressure safety relief valves. Using the correct one for your application is critical for safety. If you need help picking the right one, please call us for assistance.

Relief valves are designed to create the proper pressure within your tank, ensuring there isn"t a build-up of too much pressure. When it comes to adjusting relief valves, many cautions and warnings need to be taken into consideration. Certain relief valves allow adjustment, but extreme caution needs to be taken as improper confirmation on how the adjustment went could cause significant damage.

In this blog, we will go over (including the use of a chart) how to select the proper size relief valve for your application, and tips on safely and properly adjusting a relief valve.

Every installation where the pump has the possibility of producing more pressure than the pressure tank"s capability must have a relief valve installed. Without a relief valve, an accidental sticking of the pressure switch contacts could cause the pump to continue running which could result in the pressure tank bursting.

It is important to note that not all relief valves can be adjusted. Heavy duty relief valves have the capability to be adjusted, but it is the installer"s responsibility to select and confirm that

The main responsibility of the system designer or installer is to accurately select a pressure relief valve that has good flow characteristics that can maintain a maximum pressure considerably lower than the system"s designed pressure. Typically, this can be determined by knowing the maximum pressure rating of the pressure tank. To find this out, you may need to contact the tank manufacturer if it is not clearly labelled on the tank itself.

Below is a flow guide that you can follow to help you select the proper size relief valve for your application. If you are getting close to the maximum gallons per minute (GPM) of your system, it is recommended that you go up a minimum of one size ensuring that there is adequate flow to compensate for the friction loss that can happen in the piping.

As already stated multiple times: when working with and adjusting relief valves, you need to take extreme caution. Field adjustment is NOT recommended on pressure relief valves. If the factory setting on the relief valve is changed in the field, the installer must test the system to ensure the setting that was changed will still allow good pressure relief for the size of the entire system.

All the adjusting screws you will need are concealed with acorn nuts to prevent tampering. When the pump or compressor is running, you can remove any tags and the acorn nuts.

By turning the adjustment screw counterclockwise until the pressure gauge is below the desired setting, you will loosen the jam nut and reduce the spring tension.

Failing to confirm that the adjustment is executed correctly and safely could result in serious damage and injury. In order to properly verify, you will need to safely test by bypassing the pressure switch. You will need to watch the calibrated pressure gauge that"s in the system. The tester must be positioned near the manual switch at the pump to quickly shut it off if the system pressure creeps closer to the maximum rating of the pressure tank. If the output of the pump exceeds the capacity of the re-set pressure relief valve, you will need to select a higher flow rate PRV.

Relief valves add a certain peace of mind to your system. It is key to ensure that if an adjustment is needed, every step is taken with the utmost safety, and that proper testing is performed to ensure the adjustment was done correctly. Taking your time, and being aware of the cautions, will allow you to properly perform the adjustment.

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.

In order to ensure that the maximum allowable accumulation pressure of any system or apparatus protected by a safety valve is never exceeded, careful consideration of the safety valve’s position in the system has to be made. As there is such a wide range of applications, there is no absolute rule as to where the valve should be positioned and therefore, every application needs to be treated separately.

A common steam application for a safety valve is to protect process equipment supplied from a pressure reducing station. Two possible arrangements are shown in Figure 9.3.3.

The safety valve can be fitted within the pressure reducing station itself, that is, before the downstream stop valve, as in Figure 9.3.3 (a), or further downstream, nearer the apparatus as in Figure 9.3.3 (b). Fitting the safety valve before the downstream stop valve has the following advantages:

• The safety valve can be tested in-line by shutting down the downstream stop valve without the chance of downstream apparatus being over pressurised, should the safety valve fail under test.

• When setting the PRV under no-load conditions, the operation of the safety valve can be observed, as this condition is most likely to cause ‘simmer’. If this should occur, the PRV pressure can be adjusted to below the safety valve reseat pressure.

Indeed, a separate safety valve may have to be fitted on the inlet to each downstream piece of apparatus, when the PRV supplies several such pieces of apparatus.

• If supplying one piece of apparatus, which has a MAWP pressure less than the PRV supply pressure, the apparatus must be fitted with a safety valve, preferably close-coupled to its steam inlet connection.

• If a PRV is supplying more than one apparatus and the MAWP of any item is less than the PRV supply pressure, either the PRV station must be fitted with a safety valve set at the lowest possible MAWP of the connected apparatus, or each item of affected apparatus must be fitted with a safety valve.

• The safety valve must be located so that the pressure cannot accumulate in the apparatus viaanother route, for example, from a separate steam line or a bypass line.

It could be argued that every installation deserves special consideration when it comes to safety, but the following applications and situations are a little unusual and worth considering:

• Fire - Any pressure vessel should be protected from overpressure in the event of fire. Although a safety valve mounted for operational protection may also offer protection under fire conditions,such cases require special consideration, which is beyond the scope of this text.

• Exothermic applications - These must be fitted with a safety valve close-coupled to the apparatus steam inlet or the body direct. No alternative applies.

• Safety valves used as warning devices - Sometimes, safety valves are fitted to systems as warning devices. They are not required to relieve fault loads but to warn of pressures increasing above normal working pressures for operational reasons only. In these instances, safety valves are set at the warning pressure and only need to be of minimum size. If there is any danger of systems fitted with such a safety valve exceeding their maximum allowable working pressure, they must be protected by additional safety valves in the usual way.

In order to illustrate the importance of the positioning of a safety valve, consider an automatic pump trap (see Block 14) used to remove condensate from a heating vessel. The automatic pump trap (APT), incorporates a mechanical type pump, which uses the motive force of steam to pump the condensate through the return system. The position of the safety valve will depend on the MAWP of the APT and its required motive inlet pressure.

This arrangement is suitable if the pump-trap motive pressure is less than 1.6 bar g (safety valve set pressure of 2 bar g less 0.3 bar blowdown and a 0.1 bar shut-off margin). Since the MAWP of both the APT and the vessel are greater than the safety valve set pressure, a single safety valve would provide suitable protection for the system.

Here, two separate PRV stations are used each with its own safety valve. If the APT internals failed and steam at 4 bar g passed through the APT and into the vessel, safety valve ‘A’ would relieve this pressure and protect the vessel. Safety valve ‘B’ would not lift as the pressure in the APT is still acceptable and below its set pressure.

It should be noted that safety valve ‘A’ is positioned on the downstream side of the temperature control valve; this is done for both safety and operational reasons:

Operation - There is less chance of safety valve ‘A’ simmering during operation in this position,as the pressure is typically lower after the control valve than before it.

Also, note that if the MAWP of the pump-trap were greater than the pressure upstream of PRV ‘A’, it would be permissible to omit safety valve ‘B’ from the system, but safety valve ‘A’ must be sized to take into account the total fault flow through PRV ‘B’ as well as through PRV ‘A’.

A pharmaceutical factory has twelve jacketed pans on the same production floor, all rated with the same MAWP. Where would the safety valve be positioned?

One solution would be to install a safety valve on the inlet to each pan (Figure 9.3.6). In this instance, each safety valve would have to be sized to pass the entire load, in case the PRV failed open whilst the other eleven pans were shut down.

If additional apparatus with a lower MAWP than the pans (for example, a shell and tube heat exchanger) were to be included in the system, it would be necessary to fit an additional safety valve. This safety valve would be set to an appropriate lower set pressure and sized to pass the fault flow through the temperature control valve (see Figure 9.3.8).

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.