north american safety valve industries free sample

Of all the challenges you face keeping your customers’ plants operating at full capacity, safety and relief valves shouldn’t be one of them. NASVI’s job is to give you the confidence that your valve supply chain is rock solid regardless the pressure it’s under.

Safety valves, when properly maintained, can last a long time—upwards of 30 years or more. Much more. Recently, a century-old valve arrived at NASVI for repair. After machining and lapping […]

William Rock III, NASVI Valve Disassembler Since 2001 When a valve arrives at our facility for remanufacturing, William Rock III (Bill) is ready and waiting on the front line. He […]

Bronze, steel and stainless steel safety relief valves for air, gas, steam, liquid and vacuum service that meet ASME Section VIII, ‘UV’; Section I, ‘V’, are National Board certified and […]

When it comes to safety valve experience NASVI employees have a mountain of knowledge. Guess how many years of collective experience these three long-time employees have in this short video. […]

This direct spring-operated pressure relief valve, part of the Series 60 and 80, uses special internals and soft seats for optimum, accurate performance. Of course, we have them in stock. […]

The NASVI team goes the extra step in safety valve quality control. Before we ship any valve, we set and test them to the end user’s specifications. This is an […]

Q: My customer has a 2-inch line. Do I need to sell them a 2-inch safety valve? A: Safety valves should be sized and selected based on the set pressure […]

Not only is Kunkle’s 6252/6254 among their largest valves, also it’s a very sought-after one. You guessed it; we keep several in stock. For general application, it is suitable for […]

Valve manufacturers are not immune from the supply chain issues plaguing most industries right now. It’s predicted that it will take some time for shipping channels to be adjusted. NASVI […]

With supply chain disruptions hitting manufacturers, it’s important to be proactive as we approach heating season. With 35,000 relief and safety valves in stock & same day shipping, our extensive […]

Supply the following information: Example: 1.  Quantity of Valves 4 2.  Size of Valve Inlet and Outlet 1 ½” x 2” 3.  Type, Model or Figure Number 1905FC 4.  Manufacturer Consolidated 5.  Inlet and […]

If you’re searching for a new Consolidated 1700 Series Maxiflow™ safety valve, or the 2700 and 1900-P1 Series economizer valves, look no further than NASVI. We’re the only company in […]

Did you know that NASVI has 35,000 safety & relief valves ready to ship at a moment’s notice? Or that warehouse is so huge (63,000 square feet!) we have a […]

NASVI pressure tests over 150 valves every day. Watch the process from adjusting the blow down ring to field service guidelines and performing the test pop, to sealing and shipping […]

If your customers are requesting a Kunkle liquid relief valve, model 218, then it’ll come as no surprise to you that not all distributors stock them and the manufacturer’s lead […]

A cracked valve, a broken part. There are always unwelcome surprises during a scheduled or unplanned shut down. Operations need to be back up and running ASAP. Don’t wait 7-10 […]

A No Brainer. Wearing face masks and social distancing is a no brainer. It isn’t pleasant, but you do what you have to do. Selling safety valves is also a […]

If you’re on the hunt for a new Consolidated 1700 Series Maxiflow™ safety valve, or the 2700 and P1 Series economizer valves, look no further than NASVI. We’re the only […]

What’s the purpose of a drip pan elbow? It provides a means to handle condensate from safety valves used in steam applications. Where are drip pan elbows used? The drip […]

When you sell safety valves, your customers are under pressure to get what they need fast. That’s why NASVI stocks the largest selection of Kunkle Valves for a variety of […]

Suggest a NASVI Valve Exchange Program. If your customer has several safety valves in need of repair but can’t afford to shut down for lengthy repairs, there’s an easy solution: […]

Offer remanufactured safety valves and watch sales grow. More companies today have found that it makes sense to rely on remanufactured safety valves. For most industrial uses, remanufactured valves offer […]

Offer NASVI’s quick turnaround on repair and testing services. At NASVI, our repair services are designed to keep: Your customer’s safety and relief valves at peak operating efficiency, and Put […]

You don’t have to be an expert in the field of safety and relief valves to sell them because that’s our job. And we’re only a phone call away. We’ll […]

Today, many companies are finding when maintenance budgets need to be stretched; a safe way to save is to rely on remanufactured safety valves. For most industrial uses, remanufactured valves […]

Increase profits, make our new Repair Facility your first stop. North American’s new Service Center is equipped to handle any safety valve repair. NASVI has the specifications for nearly every […]

A.J. Podschwit has an extensive background in industrial sales. In his role as application engineer at North American, he puts it to use every day. “Customers call with specs, but […]

Our goal is to make it easy for you to profit from the sales of safety and relief valves. Call us for assistance. We can help you with sales planning, […]

I am writing this on March 26 and the virus is well into its third week in the United States. We received a letter from Homeland Security that North American […]

Earlier this year, I shared a little product education on safety valves that can make you look really smart to customers, which usually means more orders for everything you sell. […]

• More than 35,000 valves in 3,100 varieties • Currently set and ship over 200 valves per day • We repair over 40 valves a week with plenty of capabilities […]

Kolby Gabbert has been with North American for nearly a year, and compared to many NASVI employees, he’s still a newcomer. Kolby is an application engineer and enjoys the customer […]

Offer North American’s remanufactured safety valves as an alternative and watch your sales grow. Many companies have found that it makes sense to rely on remanufactured safety valves. For most […]

Our repair service center is designed to keep your customer’s safety and relief valves at peak operating efficiency. In addition to an experienced, skilled staff, NASVI’s Service Center is equipped […]

Our giant inventory and remarkable selection awaits your call. One of the customers recently inquired about the availability of five 4-inch liquid flanged valves. The end user had made a […]

Today, many companies are finding when maintenance budgets need to be stretched; a safe way to save is to rely on remanufactured safety valves. For most industrial uses, remanufactured valves […]

Our repair service center is designed to keep your customer’s safety and relief valves at peak operating efficiency. And put extra profits in your pocket. North American’s Service Center is […]

Offer NASVI’s quick turnaround on repair and testing services. At NASVI, our repair services are designed to keep: Your customer’s safety and relief valves at peak operating efficiency, and Put […]

For some reason I get asked pretty frequently if I’m a surgeon. Believe me, you don’t want me operating on you. I tell people I’m the Safety Value Doctor because […]

Offer NASVI’s quick turn-around on repair and testing services. Over the years, our Service Center has proven popular with maintenance managers. It allows your customer’s plant to have their valves […]

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.

Our repair service center is designed to keep your customer’s safety and relief valves at peak operating efficiency. And put extra profits in your pocket.

North American’s Service Center is equipped to handle any safety valve repair. NASVI has the specifications for nearly every safety valve ever made—allowing technicians to make repairs to exact specifications. The center has six lathes on site, so technicians can restore tolerances on existing parts in quick order. If a part cannot be restored, it can generally be replaced from our extensive parts inventory.

Once repairs are complete, valves are tested and then set at one of six, fully equipped test stations. The boiler is on every day for testing steam valves. It’s always ready, allowing us to set and ship your valves fast.

Over the years, our Service Center has proven popular with maintenance managers. It allows the plant to have their valves repaired, serviced and set quickly, which minimizes downtime. They also like the service because it saves them money.

Our repair service also includes updating the valve to the latest design standard when necessary. All valves serviced in our repair facility carry a one-year standard warranty. North American holds ASME’s V and UV stamps and National Board’s NB and VR stamps. The next time your customer has questions about repairing or upgrading their safety or relief valves, give one of our application engineers a call.

With North American’s Service Center, you can maximize your customer’s uptime while saving both time and money. Make our Service Center your service center. Just one call will provide quick solutions to all your repair needs. An application engineer will work directly with you to customize a program to meet your customer’s needs.

You don’t have to be an expert in the field of safety and relief valves to sell them. We are here to help. Our goal is to make it easy for you to profit from the sales of safety and relief valves. Our expertise comes from taking care of our customers for over 42 years. And our large inventory allows us to offer same day shipment from stock on every valve Kunkle makes.

The sole responsibility of our dedicated applications engineers is to take care of your requirements. We will help you with sales planning, product selection and after sale service when needed. We will even provide you with catalogs that have no reference to NASVI. Our valuable advice is free and as close as your phone. So the next time your customer calls and needs a safety or relief valve, call a NASVI Applications Engineer.

They’ll have a quick answer on price, availability and shipment. When it comes to selling safety valves, you don’t have to stock anything. Simply call 1-800-800-8882 or visit us on the web at www.nasvi.com. We’ll make it easy for you!

Our two-truck unit responds to customer requests anywhere, offering on-site repair and resetting of safety valves during scheduled maintenance shutdowns.

Step into the mobile repair unit and you’ll find all the equipment necessary to perform highest-caliber repairs: sand blaster, compressor, lathe, mill/drill press, lapping machine–-it’s all inside. There’s also a Consolidated® seat-resurfacing machine with all adapters for every orifice in the Maxi-Flow® boiler line. Completed valve work will carry the VR stamp.

The Field Service Unit also includes a state of-the-art computerized lift-assist testing unit that allows for testing set pressures and resetting high-pressure safety valves in the field. The testing unit makes testing valves that are welded in-line or stationary possible without removing the valves. Your customers won’t be required to pressure down or increase pressure to test for set pressure. The lift assist testing unit also allows for resetting valves after repairs have been made while the valves are on-line.

If you have prospects or customers that bought their replacement valves elsewhere because you haven’t been able to provide on-site service, you will want to get back with them and talk about this service. If you have questions about pricing and scheduling of our Field Service Unit, give us a call at (800) 800-8882.

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As one of the leading manufacturers of cavity free plug valves and special valves, AZ supplies to production plants in the chemical, petrochemical, pharmaceutical, paper, food industries as well as for nuclear power plants and many other areas. Special valves for highest demands in areas with high operating pressures and aggressive, toxic or abrasive media are designed and developed together with our customers. In the 50 years of the company’s existence, AZ has continuously developed to meet the increasing requirements of customers active around the world and today AZ manufactures internationally on four continents.

In 2023, the sales of Pressure Relief Valve in Global Market is expected to reach US$ 4,509.8 Mn. and is projected to expand steadily at a CAGR of 4.6% to reach a market valuation of close to US$ 7,070.9 Mn by 2033.

In recent past valve costs have increased globally, which can be attributed to growing tariffs from the North American region, particularly the US. Leading players from the European and American regions have facilities in both high- and low-income nations. In contrast, labor-intensive production processes like the creation of rough castings for valves and valve components take occur in low-cost manufacturing nations like China. These processes include design, research and development, and testing. Due to low prices and quality maintenance, OEMs are able to do so. However, growing US government tariffs on steel and aluminum imports from China have had a substantial negative influence on pressure relief valve profit margins and costs.

However, the rapid growing industrialization and increasing safety precaution are the factors that are expected to fuel the market growth of Pressure relief valves across the globe during the assessment period, the Pressure relief valve market is expected to experience demand growth with CAGR of 4.6% during the forecasted period.

From 2017 to 2022, the Global Pressure Relief Valve Market expanded at a CAGR of around 2.4%. The advancement in product technology to connect the valves digitally enables end users to monitor pressure in various applications digitally which has generated significant demand from the various industry sector during the forecasted period.

Numerous applications where pressure levels are crucial for continuous and efficient machinery performance demand for the utilization of pressure relief valves. These include the various sectors operating with steam, air, gas, or liquid such as oil and gas, power generation and the petrochemicals industry. Multiphase applications and chemical processing systems both have high installation rate of pressure relief valves. With rapid development industrial sector & expansion of oil & Gas pipelines across the developing as well as developed economies the demand for PRV is also expected to expand, Persistence Market Research expects the market to expand at a 4.6% CAGR through 2033.

Both emerging and advanced regions have seen a surge in oil and gas consumption. In order to meet the rising demand and supply for oil and gas, industries are concentrating on expanding their production facilities through onshore and offshore exploration. Since the oil and gas sector is one of the key end uses for the global pressure relief valves market thus expanding oil & gas Sector is generating lucrative opportunity for the demand growth of PRVs in upcoming period.

Furthermore, growing regulation for use of pressure relief valves in power generation sector is further set to create opportunities for the market. For instance, there are currently about 50 nuclear reactors under development. By safeguarding turbines, super heaters, and boilers to enable the stations to operate at prescribed pressures, pressure relief valves play a crucial part in the successful and safe operations of nuclear facilities.

Manufacturing businesses will be significantly and directly impacted by the Asia Pacific region"s volatile and uncertain markets. The operational costs of the manufacturing processes, which are the main concern of manufacturers, will be directly impacted by rising tariffs and raw material costs used to manufacture valves. Rising raw material costs immediately impact the integrity of the supply chain and the selling price of a product. Manufacturers in the Asia Pacific region are becoming increasingly concerned about the steady growth in cost of the raw materials used to make pressure relief valves. This is expected to, restrain the market"s expansion for pressure relief valves.

With an absolute dollar opportunity of around US$ 600.0 Mn, North America is expected to be the most lucrative market for pressure relief valves suppliers. U.S is leading the North American market, and is expected to witness a 1.5X growth during 2023-2033. The market for pressure relief valves has recently experienced considerable growth in sales as a result of growing industrialisation and advancements in urban waste water management systems. Apart from that U.S. is also second largest importer & Exporter of Pressure relief valves, which makes it a targeting region for the manufacturers & Suppliers.

In 2023, the German Pressure Relief Valve market is likely to hold around 25% of the market by value share in Europe. Germany"s extensive remanufacturing capabilities are likely to play a crucial part in development of industrial growth. Sales growth for pressure relief valves is anticipated to be boosted in the upcoming years as manufacturers are planning to invest more in safety & developments of industrial Sites.

With a CAGR of 5.9%, India is expected to lead the South Asian market throughout the assessment period and experience significant expansion. Pressure relief valve demand is anticipated to increase as a result of India"s low production and labour costs, as well as less regulations & certifications required for PRVs, which are encouraging various industry players, including oil & gas, pharmaceutical, chemical, and textile manufacturers, to expand their manufacturing facilities in India.

By the end of the assessment period, spring-loaded pressure relief valves will hold a value share of over 40% of the market for pressure relief valves worldwide. Due to its broad range of applications and other technological advantages over other valves, this valve is widely utilized. The design and use of pressure relief valves is covered by a number of international codes and standards, the most popular of which being the ASME (American organization for mechanical engineers) Boiler and Pressure Vessel Code, also known as ASME code. Despite the fact that this code varies by region.

In 2023, the demand for pressure relief valves is primarily driven by the Medium Pressure segment in Set Pressure segment of the market. By the end of the forecast period, it is projected that pressure relief valves with a medium pressure range will still be widely utilized in a variety of end use sectors. The market for medium pressure relief valves is expected to continue expanding due to rising end-use sectors including oil and gas, chemical, and others.

The primary purpose of a safety valve is to protect life, property and the environment. Safety valves are designed to open and release excess pressure from vessels or equipment and then close again.

The function of safety valves differs depending on the load or main type of the valve. The main types of safety valves are spring-loaded, weight-loaded and controlled safety valves.

Regardless of the type or load, safety valves are set to a specific set pressure at which the medium is discharged in a controlled manner, thus preventing overpressure of the equipment. In dependence of several parameters such as the contained medium, the set pressure is individual for each safety application.

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.