boiler safety valve testing procedure quotation

Safety is of the utmost importance when dealing with pressure relief valves. The valve is designed to limit system pressure, and it is critical that they remain in working order to prevent an explosion. Explosions have caused far too much damage in companies over the years, and though pressurized tanks and vessels are equipped with pressure relief vales to enhance safety, they can fail and result in disaster.

That’s also why knowing the correct way to test the valves is important. Ongoing maintenance and periodic testing of pressurized tanks and vessels and their pressure relief valves keeps them in working order and keep employees and their work environments safe. Pressure relief valves must be in good condition in order to automatically lower tank and vessel pressure; working valves open slowly when the pressure gets high enough to exceed the pressure threshold and then closes slowly until the unit reaches the low, safe threshold. To ensure the pressure relief valve is in good working condition, employees must follow best practices for testing them including:

If you consider testing pressure relief valves a maintenance task, you’ll be more likely to carry out regular testing and ensure the safety of your organization and the longevity of your

It’s important to note, however, that the American Society of Mechanical Engineers (ASME) and National Board Inspection Code (NBIC), as well as state and local jurisdictions, may set requirements for testing frequency. Companies are responsible for checking with these organizations to become familiar with the testing requirements. Consider the following NBIC recommendations on the frequency for testing relief valves:

High-pressure steam boilers greater than 15 psi and less than 400 psi – perform manual check every six months and pressure test annually to verify nameplate set pressure

High-pressure steam boilers 400 psi and greater – pressure test to verify nameplate set pressure every three years or as determined by operating experience as verified by testing history

High-temperature hot water boilers (greater than 160 psi and/or 250 degrees Fahrenheit) – pressure test annually to verify nameplate set pressure. For safety reasons, removal and testing on a test bench is recommended

When testing the pressure relief valve, raise and lower the test lever several times. The lever will come away from the brass stem and allow hot water to come out of the end of the drainpipe. The water should flow through the pipe, and then you should turn down the pressure to stop the leak, replace the lever, and then increase the pressure.

One of the most common problems you can address with regular testing is the buildup of mineral salt, rust, and corrosion. When buildup occurs, the valve will become non-operational; the result can be an explosion. Regular testing helps you discover these issues sooner so you can combat them and keep your boiler and valve functioning properly. If no water flows through the pipe, or if there is a trickle instead of a rush of water, look for debris that is preventing the valve from seating properly. You may be able to operate the test lever a few times to correct the issue. You will need to replace the valve if this test fails.

When testing relief valves, keep in mind that they have two basic functions. First, they will pop off when the pressure exceeds its safety threshold. The valve will pop off and open to exhaust the excess pressure until the tank’s pressure decreases to reach the set minimum pressure. After this blowdown process occurs, the valve should reset and automatically close. One important testing safety measure is to use a pressure indicator with a full-scale range higher than the pop-off pressure.

Thus, you need to be aware of the pop-off pressure point of whatever tank or vessel you test. You always should remain within the pressure limits of the test stand and ensure the test stand is assembled properly and proof pressure tested. Then, take steps to ensure the escaping pressure from the valve is directed away from the operator and that everyone involved in the test uses safety shields and wears safety eye protection.

After discharge – Because pressure relief valves are designed to open automatically to relieve pressure in your system and then close, they may be able to open and close multiple times during normal operation and testing. However, when a valve opens, debris may get into the valve seat and prevent the valve from closing properly. After discharge, check the valve for leakage. If the leakage exceeds the original settings, you need to repair the valve.

According to local jurisdictional requirements – Regulations are in place for various locations and industries that stipulate how long valves may operate before needing to be repair or replaced. State inspectors may require valves to be disassembled, inspected, repaired, and tested every five years, for instance. If you have smaller valves and applications, you can test the valve by lifting the test lever. However, you should do this approximately once a year. It’s important to note that ASME UG136A Section 3 requires valves to have a minimum of 75% operating pressure versus the set pressure of the valve for hand lifting to be performed for these types of tests.

Depending on their service and application– The service and application of a valve affect its lifespan. Valves used for clean service like steam typically last at least 20 years if they are not operated too close to the set point and are part of a preventive maintenance program. Conversely, valves used for services such as acid service, those that are operated too close to the set point, and those exposed to dirt or debris need to be replaced more often.

Pressure relief valves serve a critical role in protecting organizations and employees from explosions. Knowing how and when to test and repair or replace them is essential.

Boiler explosions have been responsible for widespread damage to companies throughout the years, and that’s why today’s boilers are equipped with safety valves and/or relief valves. Boiler safety valves are designed to prevent excess pressure, which is usually responsible for those devastating explosions. That said, to ensure that boiler safety valves are working properly and providing adequate protection, they must meet regulatory specifications and require ongoing maintenance and periodic testing. Without these precautions, malfunctioning safety valves may fail, resulting in potentially disastrous consequences.

Boiler safety valves are activated by upstream pressure. If the pressure exceeds a defined threshold, the valve activates and automatically releases pressure. Typically used for gas or vapor service, boiler safety valves pop fully open once a pressure threshold is reached and remain open until the boiler pressure reaches a pre-defined, safe lower pressure.

Boiler relief valves serve the same purpose – automatically lowering boiler pressure – but they function a bit differently than safety valves. A relief valve doesn’t open fully when pressure exceeds a defined threshold; instead, it opens gradually when the pressure threshold is exceeded and closes gradually until the lower, safe threshold is reached. Boiler relief valves are typically used for liquid service.

There are also devices known as “safety relief valves” which have the characteristics of both types discussed above. Safety relief valves can be used for either liquid or gas or vapor service.

Nameplates must be fastened securely and permanently to the safety valve and remain readable throughout the lifespan of the valve, so durability is key.

The National Board of Boiler and Pressure Vessel Inspectors offers guidance and recommendations on boiler and pressure vessel safety rules and regulations. However, most individual states set forth their own rules and regulations, and while they may be similar across states, it’s important to ensure that your boiler safety valves meet all state and local regulatory requirements.

The National Board published NB-131, Recommended Boiler and Pressure Vessel Safety Legislation, and NB-132, Recommended Administrative Boiler and Pressure Vessel Safety Rules and Regulationsin order to provide guidance and encourage the development of crucial safety laws in jurisdictions that currently have no laws in place for the “proper construction, installation, inspection, operation, maintenance, alterations, and repairs” necessary to protect workers and the public from dangerous boiler and pressure vessel explosions that may occur without these safeguards in place.

The American Society of Mechanical Engineers (ASME) governs the code that establishes guidelines and requirements for safety valves. Note that it’s up to plant personnel to familiarize themselves with the requirements and understand which parts of the code apply to specific parts of the plant’s steam systems.

High steam capacity requirements, physical or economic constraints may make the use of a single safety valve impossible. In these cases, using multiple safety valves on the same system is considered an acceptable practice, provided that proper sizing and installation requirements are met – including an appropriately sized vent pipe that accounts for the total steam venting capacity of all valves when open at the same time.

The lowest rating (MAWP or maximum allowable working pressure) should always be used among all safety devices within a system, including boilers, pressure vessels, and equipment piping systems, to determine the safety valve set pressure.

Avoid isolating safety valves from the system, such as by installing intervening shut-off valves located between the steam component or system and the inlet.

Contact the valve supplier immediately for any safety valve with a broken wire seal, as this indicates that the valve is unsafe for use. Safety valves are sealed and certified in order to prevent tampering that can prevent proper function.

Avoid attaching vent discharge piping directly to a safety valve, which may place unnecessary weight and additional stress on the valve, altering the set pressure.

IVI is a VR certified safety valve repair facility, approved by the National Board of Boiler and Pressure Vessel Inspectors as a VR certificate holder (stamp 179). We certify pressure relief valves in the shop and in the field for sections V and UV. We also perform on-site testing (while the plant operates) providing documented reports for all valves tested. We are also certified to administer special process conversions regarding machining, welding, heat treating, and N.D.T. (non-destructive testing) with our VR certificate.

With our VR stamp, we repair all types of pressure relief valves such as Consolidated, Crosby, Kunkle, Farris, Spence, Anderson Greenwood, and numerous other O.E.M. safety and pressure relief valves.

The primary role of a safety relief valve is to prevent over-pressure situations in pressurized vessels or systems. If the tank’s relief valve fails, it can lead to an accident that destroys property, life, or landscape.

The National Board of  Boiler and Pressure Vessel Inspectors is one of the governing bodies for the testing and/or repair of ASME Safety Relief Valves.

You, as the owner of the valve, can test it, but it must be done in accordance with the National Board Inspection Code and your state’s and/or local regulations.

Based on the National Board Code, which bases their inspection intervals on what type of service the valve is used for, the following intervals are suggested:

Also, keep in mind that this piping should be oriented so that no liquid relieved through this piping can flow back and rest on the ASME safety relief valve’s outlet port.

The ASME relief valves are set to fully open at its “set” pressure but will begin to partially open before then – normally at 10% below its set pressure.

If your valve is allowed to do this, trash and/or corrosion can set in over time which could prevent the valve from either closing completely or from fully opening, either of which is not a favorable solution.

For example on a residential water heater the TPR is typically set to open at a pressure of 150 psi or if the water temperature reaches 210°F. On older water heaters using older TPR valves you may find the valve rated to open at 125 psi.

In all events the opening pressure of a pressure or temperature relief valve should never exceed the working pressure of the tank - such a condition is unsafe and violates water heater warranties and plumbing codes.

An inspection of a T&P valve for its ability to perform safely includes a number of checkpoints such as looking for leaks, mechanical damage, blockage, or for a TPRV that is not properly sized or matched to the equipment it"s supposed to protect.

In our photo I"m pointing to the test lever on the temperature/pressure relief valve on a residential water heaters. These safety devices are required on all heated water or steam vessels or tanks and are found on both residential and commercial water heating equipment.

Illustration: typical parts of the operating mechanism of a relief valve, adapted from FlowStar Safety Relief valves cited below. Note that in this illustration the temperature sensing probe that would extend into the hot water from the valve base is not shown. Flowstar is a safety relief valve provider in the UK.

In this illustration key operating or moving parts of this relief valve are identified as (3) Lifting lever, (4) Spring, (6) Bonnet, (9) Disk, (12) Inlet body, (16) Spring Carrier, (17) Spindle or lifting rod operated by (3) the test lever.

It"s a holiday (stores are closed) or a Sunday or late at night such that if the valve fails to close you will not be able to arrange prompt repairs, leaving the building and occupants with no hot water or no heat

Observe the valve discharge: lifting the test lever should result in (hot) water flushing through the valve and its discharge tube into a bucket placed below the discharge tube for that purpose or into a floor drain.

the installation of any relief valves.- TANKLESS WATER HEATER USE & CARE MANUAL [PDF] for Rheem®, RUUD®, Richmond®, Paloma®, and Sure Comfort® residential tankless water heaters.

After lifting the easing lever or relief valve opening lever, lower it gently back to its closed position. You can let the TPR valve "snap" closed on its own - as is recommended by typical water heater TPR valve instructions but Rheem points out [citation needed] that rough handling of the relief valve test lever, such as allowing it to "snap" closed, can damage the temperature and pressure relief valve - a dangerous condition that could lead to a water heater explosion

OPINION: I think that the "snapping relief valve shut" problem is likely to occur principally when testing an old valve whose valve seat washer is already dry and brittle. Letting a newer valve (5 years old or less) test lever snap shut under control of the lever"s own spring ought cause no damage.

If water does not flow freely when the temperature/pressure relief valve is opened, the valve should be replaced by a licensed plumber, making sure that an approved, properly-rated TP valve is installed.

If your temperature/pressure relief valve has not been tested or replaced sooner than five years, Rheem recommends that the TP valve should simply be replaced. More frequent replacement of the safety valve may be needed in areas where hard water is found.

Watch out: some of the TPR valve test procedures and articles we reviewed point out that testing the valve by operating it more often than recommended risks damaging the valve, causing leaks, and possibly making it unsafe.

If the relief valve closes but continues to drip, you might be able to stop the drip by flushing the valve seat (lifting the test lever) a time or two.

When that does not work, try tapping gently on the center lift pin or rod to try to re-seat the valve washer. Don"t bang the heck out of the valve or you may convert a small leak into a dangerous hot water catastrophe.

If water continues to flow you may need to remove pressure from the hot water system or boiler; at a water heater this may be achieved by running hot water at nearby sinks or tubs

Considering the risks and costs of a bad T&P valve flooding a home at any time, particularly one that"s in the process of being sold, at least some home inspectors will eschew actually testing the T&P valve by lifting the test lever.

Watch out: if you do not test the T&P valve at a home inspection you should explain why (risk of a building flood) and you should advise your client to have such a test performed by their plumber promptly on taking control of the property. Avoid an ugly surprise by explaining what could go wrong.

Excessive temperature or pressure: A heating appliance that is at a too-high temperature or too-high pressure (a first check is to look at the temperature settings on the equipment and on a heating boiler to look at the system pressure: both should be below the valve-opening temperature and pressure given on the TPR valve label)

Watch out: the reasons that a dripping or leaking relief valve is dangerous include failure to notice that the system the valve is intended to protect is already operating at an unsafe temperature or pressure, OR the risk that continued leakage leads to scale clogging of the valve so that it cannot open in an emergency.

Virtually every temperature / pressure relief valve manufacturer whose product line includes TPR valves with a test lever or mechanism recommends that the temperature and pressure safety relief valve be tested, though the test interval recommended ranges from three years to six months, varying by type of inspection and valve type.

Really? In nearly 50 years of building inspection and repair work I [DF] have never once found a residential water heater installation at which the T&P valve is inspected regularly much less annually.

Typically the valve is noticed and replaced when the building occupants or owner observe a leak. Nevertheless we urge readers, plumbers, and other building occupants and owners to be sure that the recommendations of their TPR or easing valve manufacturer are followed. Failing to do so is dangerous.

Details of TPR valve inspection, including other inspection points beyond the actual valve testing (discussed just below) are at RELIEF VALVES - TP VALVES - home

The answer is: it"s debatable. Some inspectors test the valve, providing an extra level of expert safety inspection, while others, afraid of a flood or hoping to shorten their job-time by reducing their inspection scope, skip this step.

OPINION: The T&P valve is a critical safety device on water heaters and heating boilers and is a standard safety device found in most buildings. In our opinion, omission of any inspection of the TPR valve whatsoever would be malpractice, putting building occupants at risk. A building professional should know better.

But what about going beyond visual inspection? Under most home inspection standards that expect the inspector to operate "normal homeowner or user controls" on building equipment, one could argue that the inspector both can and should "test" the TPR valve by lifting the test lever.

Watch out: The results of testing a T&P valve, if the valve won"t close again, can be a flood of hot water in the building, risking burns, water damage, and considerable shouting.

Speaking from personal experience, I [DF] have operated a T&P valve only to see the old valve spit out its valve seat washer, leading to a horrible hot water flood.

Back in the day before I knew much about this hazard, during a plumbing job I made an emergency "Sunday night" replacement TPR valve seat washer (cut out of a piece of Tupperware©) to permit the owners to have hot water until the valve could be replaced the next day. Under normal circumstances this is not something you should attempt.

Watch out: If the lift/test lever on a temperature/pressure relief valve is blocked from movement that prevents the valve from being tested - a step recommended at least annually by relief valve manufacturers.

Watch out: Depending on the relief valve model and design, a blocked relief valve test lever may prevent the valve from opening in response to pressure or temperature.

Special thanks to home inspector "anonymous", a member of the ASHI Technical Review Committee, for suggesting clarification of the hazards of blocked pressure or temperature relief valve test lever hazards - by private email 2017/04/21

American Water Heater Co., INSTALLATION INSTRUCTIONS FOR TEMPERATURE AND PRESSURE VALVE [PDF] - Retrieved 2018/04/21, original source: http://www.americanwaterheater.com/media/23796/6500260.pdf

ANSI: Relief Valves and Automatic Gas Shutoff Devices for Hot Water Supply Systems, ANSI Z21.22, and the Standard CAN1-4.4 Temperature, Pressure, Temperature and Pressure Relief Valves and Vacuum Relief Valves

Ball, Joseph F., P.E., Field Repairs of Pressure Relief Valves Part 2: Testing Mr. Ball is the Director, Pressure Relief Department, National Board of Boiler and Pressure Vessel Inspectors,

Technology of Steam, Bulletin of National Board of Boiler and Pressure Vessel Inspectors, (2014 pp 8-10) - Retrieved 2018/04/21, original source: https://www.nationalboard.org/SiteDocuments/Bulletins/SU2014.pdf

Mr. Ball is director of the National Board Pressure Relief Department. He is responsible for pressure relief device new construction and repair certification programs, and test lab operations. He is also responsible for the conduct of shop reviews of valve and rupture disk manufacturers, assemblers, repair organizations, and test laboratories, and is an ASME Authorized Observer for the National Board Testing Laboratory.

National Board of Boiler and Pressure Vessel Inspectors Mailing Address: 1055 Crupper Avenue Columbus, Ohio 43229-1183 USA, Phone: 614.888.8320 Email: information@nationalboard.org

California, City of Merced, RELIEF VALVE DISCHARGE PIPING PLUMBING CODE [PDF] based on UPC 608.5, building code interpretation regarding the discharge piping from water heater temperature-pressure relief valves based on the California Plumbing Code, Merced Civic Center

CROSBY PRESSURE RELIEF VALVE ENGINEERING HANDBOOK [PDF] Technical Document No. TP-V300, (1997), Crosby Valve, Inc., retrieved 2018/04/21, original source: http://www.isibang.ac.in/~library/onlinerz/resources/enghandbook3.pdf

CROSBY RELIEF VALVE Series 800, 900 PRESSURE RELIEF VALVE INSTALLATION, MAINTENANCE, ADJUSTMENT INSTRUCTIONS [PDF] - Op. Cit. retrieved 2018/04/22, original source: http://50.244.15.10/techlib/Crosby/Crosby_ReliefValve_800_900_iom_D498.pdf

Pentair Valves & Controls, PENTAIR PRV ENGINEERING HANBOOK [PDF] (2012) - Anderson Greenwood, Crosby and Varec Products, Pentair Valves & Controls, Retrieved 2018/04/21, original source: http://www.iomosaic.com/diersweb/docs/pvcmc-0296-us_tcm106-35825.pdf

Spirax Sarco, STEAM SYSTEM SAFETY VALVE INSTALLATION [PDF], Spirax Sarco Limited, Tel: K+44 (0) 1242 521361, Offices world wide, Website: http://www.spiraxsarco.com/ retrieved 2018/04/22, original source: http://www.spiraxsarco.com/Resources/Pages/Steam-Engineering-Tutorials/safety-valves/safety-valve-installation.aspx

An exploding 30-gallon water heater has the force of about one pound of dynamite.and has the power to destroy a house and injure or kill those inside. Thankfully, explosions have been significantly reduced because temperature and pressure (T&P) relief valves are now being used nationally to protect water heaters from explosion.

T&P relief valves, when installed properly, prevent high water temperatures, which can cause flashing of hot steam at faucets or any water outlets in the system, or cause an explosion. And, they prevent high pressures, which can damage the water heater system piping or components.

Watts Water Technologies Co., WATTS LFN30 N30 INSTALLATION INSTRUCTIONS, RELIEF VALVES (DIAPHRAGM ACTUATED) [PDF] Retrieved 2018/04/21, original source: http://media.wattswater.com/1910203.f

These valves protect against excessive pressure only. To prevent excessive temperature above 212°F, which might result in a hot water explosion, combined temperature and pressure protection is essential. WATTS Combination Temperature and Pressure Relief Valves give this protection.

Series 53L Pressure Relief Valves are used in residential applications to protect against excessive pressure on domestic storage tanks and tankless water heaters..... ANSI Z21.22 approved, design certified and listed by CSA, and UL listed.

I recently tested the T&P valve on my electric water heater. I let it the snap back closed, as this is what a lot of websites said, and it appeared to test fine. However, I then found on your website, which said the lever is supposed to gently raised and lowered, or the valve could be damaged. I tested the valve again in this manner. Water flowed freely and it appears to have closed back properly.

Indeed typical water heater manufacturer"s instructions mention TPR valve testing procedures. Letting the valve "snap back" closed helps assure that the stop valve seats securely against the washer. I"ve done exactly that when the valve was dripping after a test.

To actuate the valve, hold the trip lever fully open for approximately five seconds in order to flush the valve seat free of any sediment. Then permit the valve check to snap shut.- source: American Water Heater Co., - Source: AMERICAN WATER HEATER INSTALLATION INSTRUCTIONS FOR TEMPERATURE AND PRESSURE VALVE [PDF] -

However in this article we noted that Rheem has pointed out [citation needed] that rough handling of the relief valve test lever, such as allowing it to "snap" closed, can damage the temperature and pressure relief valve - a dangerous condition that could lead to a water heater explosion or BLEVE EXPLOSION.

At least once a year, lift and release the lever handle on the temperature pressure relief valve, located near the top of the water heater, to make certain the valve operates freely. Allow several gallons to flush through the discharge line to an open drain. - Source:  RHEEM ELECTRIC WATER HEATER MANUAL [PDF]

I don"t think that the snap-back is going to damage a valve that"s otherwise in good condition. But an old TPR valve that has not been tested in sometime may have a dried-out washer that will fail when the valve is tested. In that case the valve needed to be replaced even before

On rare occasions with an old valve whose valve seat was scale-coated and in another instance when the valve internal washer was dried-out, snapping back the valve led to an obvious failure: the valve dripped constantly.

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RELIEF VALVE, TP VALVE TEST at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

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TECHNICAL REFERENCE GUIDE to manufacturer"s model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop Weldon & Associates

Tired of keeping track of your valve inventory’s annual certification records? We offer complete management of your safety relief valves. With an inventory of repair parts and in stock relief valves of all sizes, we can respond to any customer emergency. We offer annual certification services as well as repair of all major brands, including Kunkle, Conbraco, Consolidated, Dresser, Apollo and more.

This is great stuff, gentlemen. I really appreciate the discussion. And yes, they did want to avoid having to force the boiler through a cycle to get steam up. They used the same little Karcher pressure-washer to wedge the boiler when the Master was laid up in her off season. Speaking of which- the Samson V"s tripple-pass boiler was last steamed almost 20 years ago then blown down and drained with the hand-holes left open. For some years after her retirement the sternwheeler Samson V was run at the dock seasonally by a group of volunteers. She was never designed for this. When in DPW service she was kept steamed up all year around except for cleanings and inspections. Also her tripple pass/ induced-draught boiler had the typical single expansion sternwheeler arrangement of exhausting steam to atmosphere up the funnel for additional draught, which was badly needed. From what I understand blow-back was a real danger. She was generally run at full speed for part of every work day. Anyways- she was run as a demonstration for some time on weekends at low levels of draught during the late 1980s beginning of the "90s. I don"t know what damage might have been done by rapidly cycling the boiler, but after getting to help punch the tubes on the Master, I got excited at the possibility of at least doing some maintenance on the Samson"s boiler to at least conserve it and unbolted the front smoke box cover. I was dismayed to find the tubes clogged with soot and scale ( from being run at low draught, I guess and then left) and the smokebox was filled to about two feet with soot. Unfortunately the Samson was also allowed to sink at her dock back in 1995 and the soot and scale in the smoke box sat there ever since and the asbestos lining of the smolebox has crumbled into the soot. I realized I was monkeying around with something I couldn"t fix so I bolted the smokebox back up and she"s sat like that ever since. Previously I removed an enormous ammount of soot and scale from the induced draught fan housing and uptakes and treated the sometimes paper thin sheet-metal w/ rust stabilizer. I am worried about the tube plates where the soot is lying on them and how fast they may be corroding. The City of New Westminster has no plans to run the ship again and I am not directly involved at the present time, but in the long run the survival of this ship will likely depend on her being as close as possible to a working vessel. This is a big question, but are there some simple things I could suggest to the current maintenance/restoration people to limit deterioration?

Ensure compliance, prevent overpressure and protect downstream equipment with industry regulated repairs for Section I & Section VIII Pressure and Safety Relief Valves. We offer rapid response and delivery times to minimize plant downtime while maximizing valve performance. We service all major makes and manufacturers for emergency, maintenance and scheduled outage needs. We also repair and replace conservation, tank and vacuum vents. Contact our sales team today to receive a quotation to repair, test or replace your safety relief valves.

Valsource is certified by The National Board of Boiler and Pressure Vessel Inspectors to repair and test Section I and Section VIII Pressure relief and Safety Relief Valves. Every valve is repaired to standards set by The National Board’s VR program. We provide 24/7 repair, testing and engineering services. We also maintain an extensive inventory and can provide replacement valves and parts with same day delivery options.

Valsource provides 24/7 repair and testing services in our shop or in the field. Our valve program allows our technicians to repair, remove, install and test your pressure relief and safety relief valves on-site. Using our AVK Electronic Test Vessel Package, our technicians are able to accurately test safety relief valves on-site without removing them from line. The primary function is to verify the set pressure in-line without having to shut down a system or unit. This service is a sure way to guarantee minimal downtime and peak valve performance. If you are preparing to service your boiler, Valsource technicians will come to your site and test each main steam safety valve to determine which valves require service. We will perform the repairs in-house or on-site using our 53’ field machining trailer, install and re-test back to calibrated set points.

If you need the best in valve repair and remanufacturing, Valsource can deliver the right options for your company. We offer rapid response times and emergency repair services available to resolve unplanned outages quickly. Our experienced technicians look forward to working with you to determine the most effective solutions for your valve repair needs.

Vinson understands that complete reliability of all Pressure Relief Devices is essential to protect, not only a plant’s assets, but most importantly all personnel and the environment. Vinson offers both field and in-shop repair services, and is proud to be one of the nation’s leading National Board certified VR & TO Repair Facilities. With certifications on air/gas/liquid and steam service (Section I & VIII), Vinson provides setting, repair and testing services on all manufacturers valves up to 10,000 psi.

A pressure relief valve (PRV) is a safety device used on pressure vessels, boilers, or integrated in process control systems to prevent damage due to excessive pressure. When a pressure exceeds a preset limit, the valve opens to relieve some of the gas, vapor, liquid, or steam, the pressure then drops to a manageable or normal value. In most scenarios, the valve will reclose or reseat so there is no downtime or interruption in the process. There are several types and classifications of pressure relief valves available in the industry, periodic testing and maintenance is mandatory for most PRV’s found in Oil & Gas, Power Generation, Chemical, and Aerospace. This maintenance and testing may occur in the field or the device may be removed for a complete overhaul in order to meet the ASME or API published codes for pressure relief devices. Proper operation is essential to prevent damage or injury to personnel.

A common approach to testing PRV’s is to install an analog test gauge or several gauges depending on accuracy requirements, apply pressure, and then watch the needle of the gauge to catch setpoint pressure. The technician may repeat the test several times in order to get a true baseline and record the results manually. The results from different technicians may vary and the accuracy of the test is subject to interpretation.

In 2013, The Boiler Safety Bureau, working with the devoted owners of these historical boilers, adopted the National Boiler Inspection Code for Historical Boilers. This allowed standardized procedures for the inspection and repairs of these boilers.

North Carolina General Statutes Chapter 95 Article 7B states that the Bureau will create and conduct a safety program to provide instruction on how to properly care, maintain, operate, and exhibit historical boilers. The program will also include instruction on how to train an apprentice.

• Range of Capability:​ MVS is able to test and repair a wide range of pressure relief valves installed on smaller 1/2-inch and up to larger 6x8 flange connections.

• Documentation:​ Technicians complete detailedrecord keeping of testing and repair reports.All information is tracked and managed in an online database.

• NBIC VR Certified:​ Test and repair procedures areperformed using calibrated instruments.Technicians can test, repair, and re-certify asrequired. If a valve fails, then it is rebuilt, retested, and repeated until acceptable.

• Capacity:​ 53-foot climate-controlled trailer isdesigned and equipped to accommodate a widerange of valves with temperature-controlled testing and repair conditions.

Is your Section 1 Boiler Safety Valve Body Wall Eroding?With many of these valves being original installation, making it is possible that  75%of all current Boiler valves were installed in the 1960’s*, theanswer is probably yes.

Body wall deterioration can occur over time in any process, and is an often overlooked factor in the review and repair of a safety valve population. Other issues related to the body wall thickness factor are that the availability of old design parts is declining, and the nozzle height of older models is different than what is available today.

The National Board Inspection Code does not address the wall thickness of Safety Valves as a component of the VR Program. This could lead to failure if the wall thickness is not sufficient for the pressure / reaction force that is acting on it. If this feature is never checked in accordance with a standard, it could prove to be the feature that causes a failure.

Additionally, inspecting the body wall thickness of your safety valve population helps to minimize the risk associated  with the current long lead time for new Safety Valves. Anticipating outages before they can occur helps to position end users to be their most competitive.

ASME B16.34, Table 3B showcases the ASME Valve Body Minimum Wall Thickness* calculations per diameter and pressure class.  Utilizing this table will help better inform the end user of the state of their valve body wall, leading to prevention of a failure.

As the experts in the service, maintenance, and repair of Safety Valves, Setpoint Integrated Solutions stands by as a trusted partner to inspect your safety valve population. We look forward to helping you identify issues before they occur while improving safety and mitigating costly downtime.

*Citation of ASME 6.1.1 of B16.34-2013 regarding Wall Thickness, which states: “For inspection purposes the wall thickness of valve bodies at the time of manufacture, except as indicated in paras. 6.1.3 through 6.1.7, 6.2, and 6.7, shall be no less than the minimum values “tm”either as shown in table 3A or table 3B or calculated using the equation shown in Mandatory Appendix VI (which yield essentially the same result). Linear interpolation may be used for wall thickness values intermediate to those listed or calculated. See Nonmandatory appendix B, section B-5 for an explanation of the interpolation procedure. The minimum thickness requirement for the body wall is applicable only as measured from internal walled surfaces. Minimum wall thickness shall not include liners, linings, or cartridges.