national safety valve factory
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.
Kunkle Relief Valve OverviewWhen it comes to industrial and commercial safety and relief valve products, Kunkle’s valve’s catalog is second to none in steam, air, gas, and liquid applications.
Kunkle relief valves range in size from ¼” NPT to 6” flange and are suitable in cryogenic and high temperatures up to 800°F environments at vacuum to 7,500 psig pressure. Kunkle Valve’s code certifications meet several global and national board standards, including ASME Section I, Section IV, and Section VIII, PED, CRN, TU and Chinese, as well as non-code requirements.
Relief Valves for Steam ServiceSteam supplies heat for industrial and chemical processes and also is used to heat buildings, supply mechanical energy, and drive mechanical equipment. Steam moves from the boiler to the end point, then heats by direct heating or indirect heating through a heat exchanger. Kunkle steam relief valves are critical to protecting equipment such as boilers, steam lines, and pressure valves, from being over-pressurized.
Relief Valves for Air ServiceKunkle designs valves for air service, for example for air compressors in mechanical shops and small factories where either low-pressure or high-pressure air is required. NASVI stocks Kunkle relief valves for air service in iron, steel and bronze for a variety of uses.
Relief Valves for Liquid ServiceKunkle also makes valves for liquid service, which provide bypass relief in a variety of applications and liquid types.
More About KunkleKunkle Valve is a renowned pressure relief valve manufacturer. Erastus B. Kunkle invented the safety valve to prevent overpressure in locomotive engines. Kunkle patented it in 1875. Since that time, Kunkle has earned its reputation for high-quality valves, and other equipment manufacturers ship their products with Kunkle’s valves pre-installed.
NASVI has stocked Kunkle safety relief valves since we opened in 1975, so we are confident when we call ourselves Kunkle safety valve experts. Every day we fulfill orders for our customers looking for Kunkle relief valves for steam, air, gas, and liquid applications.
Safety valve Model 64Safety valve 90º angular type of rapid opening (pop action), full nozzle, and spring loaded, adjusting ring, conventional or balanced.Safety valve Model 55Safety valve 90º angular type of rapid opening, semi nozzle, spring loaded.Safety valve Model 51Safety valve 90º angular type of rapid opening (pop action), full nozzle, and spring loaded, adjusting ring, conventional or balanced.Safety valve Model 3-50Safety valve 90º angular type of rapid opening (pop action), full nozzle, spring loaded, adjusting ring.Emergency Valve 2000Safety device intended for installation on storage tanks with the finality of assure a quick evacuation of large volume of fluid inside the tank in the event of an overpressure due to fire condition.Breather Valve 3400Breather valve for overpressure and vacuum, with flanged and threaded connections. This valve is categorized in three different types: Breather, Vacuum and Breather/Vacuum combined.Pilot Operated Safety Relief ValvePilot operated pressure relief valve able to operate at considerably higher set pressure than with spring loaded safety relief valves, the valve operation and lift are unaffected by back-pressure.Valve silencersNoise in some safety and control valves generates levels above 150 dBA / dBC, a situation that is a concern for the technical operations and maintenance of plants.Represented brandsWe work together with major brands adding value to our solutions and services.
Safety valves are used in a variety of applications, including air/gas, vapor, steam and liquid service. Flotech has been approved by the National Board of Boiler and Pressure Vessel Inspectors to perform safety and relief valve testing, repair and certification.
Our valve experts will focus on getting your valves tested, repaired and quickly set to the exact specifications. We evaluate the repair condition of every valve and will recommend the right solution to manage your maintenance program.
Valvulas Nacional-Spain are part of the Pekos Group and have been designing and manufacturing Safety Relief Valves since 1976. Offering specialised products to the petrochemical, chemical and thermo-solar industries with approvals including ASME VIII-Div.1, API 526, and ISO 4126.
SVI Industrial offers both shop and field diagnostic and control valve repair services. By utilizing “Bench Mark” diagnostic equipment, we can input your control valve’s configuration information, run baseline tests, then provide detailed documentation that will show the valve’s performance. This information can be used to determine if your control valve needs minor instrumentation calibrations or possibly a major overhaul.
We can work independently or with your reliability engineers to establish a database of your safety relief devices throughout your plant. You can count on our experience and knowledge to establish a recommended frequency of safety valve testing and repairs of your safety valves, that meet your corporate requirements and requirements set by your state inspector and insurance auditor based on “best practices” from the National Board.
SVI Industrial holds three “VR” certificates from the National Board of Boiler and Pressure Inspectors authorizing our technicians to repair, set and certify safety pressure valves inline, on our customer’s site and at any of our shop locations for both ASME Section I and VIII code stamped safety valves. Our skilled valve technicians will evaluate the condition of your safety valve, make the proper recommendations and work diligently to get your safety valves tested, repaired and set to the correct specifications and back in-line as quickly as possible in order to minimize interruption of your daily operations.
We are a turnkey service provider with the capability to service, repair or replace your welded in-line steam safety valves, including pipe prep, welding, removal and heat treating. SVI Industrial is your one-stop source for all of your industrial safety valve repair and other maintenance needs.
Pressure relief devices are used to provide a means of venting excess pressure which could rupture a boiler or pressure vessel. A pressure relief device is the last line of defense for safety. If all other safety devices or operating controls fail, the pressure relief device must be capable of venting excess pressure.
There are many types of pressure relief devices available for use in the boiler and pressure vessel industry. This inspector guide will address the most common devices found on boilers and pressure vessels. Virtually all jurisdictions require a pressure relief device to be manufactured and certified in accordance with the ASME BPV Code in addition to being capacity-certified by the National Board.
Safety Valve – This device is typically used for steam or vapor service. It operates automatically with a full-opening pop action and recloses when the pressure drops to a value consistent with the blowdown requirements prescribed by the applicable governing code or standard.
Relief Valve – This device is typically used for liquid service. It operates automatically by opening farther as the pressure increases beyond the initial opening pressure and recloses when the pressure drops below the opening pressure.
Safety Relief Valve – This device includes the operating characteristics of both a safety valve and a relief valve and may be used in either application.
Temperature and Pressure Safety Relief Valve – This device is typically used on potable water heaters. In addition to its pressure-relief function, it also includes a temperature-sensing element which causes the device to open at a predetermined temperature regardless of pressure. The set temperature on these devices is usually 210°F.
Drain holes in the device body and discharge piping, when applicable, must be open to allow drainage of liquids from over the device disk on spring loaded valves. Any liquid allowed to remain on top of the device disk can adversely affect the operating characteristics of the device.
The National Board strives to keep information in the hands of website users. Provided here are more than 70 Technical Articles previously published in the National Board BULLETINand/or from the proceedings of past General Meetings.
SVI Industrial offers both shop and field diagnostic and control valve repair services. By utilizing “Bench Mark” diagnostic equipment, we can input your control valve’s configuration information, run baseline tests, then provide detailed documentation that will show the valve’s performance. This information can be used to determine if your control valve needs minor instrumentation calibrations or possibly a major overhaul.
We can work independently or with your reliability engineers to establish a database of your safety relief devices throughout your plant. You can count on our experience and knowledge to establish a recommended frequency of safety valve testing and repairs of your safety valves, that meet your corporate requirements and requirements set by your state inspector and insurance auditor based on “best practices” from the National Board.
SVI Industrial holds three “VR” certificates from the National Board of Boiler and Pressure Inspectors authorizing our technicians to repair, set and certify safety pressure valves inline, on our customer’s site and at any of our shop locations for both ASME Section I and VIII code stamped safety valves. Our skilled valve technicians will evaluate the condition of your safety valve, make the proper recommendations and work diligently to get your safety valves tested, repaired and set to the correct specifications and back in-line as quickly as possible in order to minimize interruption of your daily operations.
We are a turnkey service provider with the capability to service, repair or replace your welded in-line steam safety valves, including pipe prep, welding, removal and heat treating. SVI Industrial is your one-stop source for all of your industrial safety valve repair and other maintenance needs.
When things go wrong, safety valves have only one function—to protect your people, plant and profits. When safety is at stake it’s vital not only to have the best equipment but make sure it is specific and fitted correctly. There is no room for mistakes: Transport valves upright and never lift them by the easing lever.
As soon as mankind was able to boil water to create steam, the necessity of the safety device became evident. As long as 2000 years ago, the Chinese were using cauldrons with hinged lids to allow (relatively) safer production of steam. At the beginning of the 14th century, chemists used conical plugs and later, compressed springs to act as safety devices on pressurised vessels.
Early in the 19th century, boiler explosions on ships and locomotives frequently resulted from faulty safety devices, which led to the development of the first safety relief valves.
In 1848, Charles Retchie invented the accumulation chamber, which increases the compression surface within the safety valve allowing it to open rapidly within a narrow overpressure margin.
Today, most steam users are compelled by local health and safety regulations to ensure that their plant and processes incorporate safety devices and precautions, which ensure that dangerous conditions are prevented.
The principle type of device used to prevent overpressure in plant is the safety or safety relief valve. The safety valve operates by releasing a volume of fluid from within the plant when a predetermined maximum pressure is reached, thereby reducing the excess pressure in a safe manner. As the safety valve may be the only remaining device to prevent catastrophic failure under overpressure conditions, it is important that any such device is capable of operating at all times and under all possible conditions.
Safety valves should be installed wherever the maximum allowable working pressure (MAWP) of a system or pressure-containing vessel is likely to be exceeded. In steam systems, safety valves are typically used for boiler overpressure protection and other applications such as downstream of pressure reducing controls. Although their primary role is for safety, safety valves are also used in process operations to prevent product damage due to excess pressure. Pressure excess can be generated in a number of different situations, including:
The terms ‘safety valve’ and ‘safety relief valve’ are generic terms to describe many varieties of pressure relief devices that are designed to prevent excessive internal fluid pressure build-up. A wide range of different valves is available for many different applications and performance criteria.
In most national standards, specific definitions are given for the terms associated with safety and safety relief valves. There are several notable differences between the terminology used in the USA and Europe. One of the most important differences is that a valve referred to as a ‘safety valve’ in Europe is referred to as a ‘safety relief valve’ or ‘pressure relief valve’ in the USA. In addition, the term ‘safety valve’ in the USA generally refers specifically to the full-lift type of safety valve used in Europe.
Pressure relief valve- A spring-loaded pressure relief valve which is designed to open to relieve excess pressure and to reclose and prevent the further flow of fluid after normal conditions have been restored. It is characterised by a rapid-opening ‘pop’ action or by opening in a manner generally proportional to the increase in pressure over the opening pressure. It may be used for either compressible or incompressible fluids, depending on design, adjustment, or application.
Safety valves are primarily used with compressible gases and in particular for steam and air services. However, they can also be used for process type applications where they may be needed to protect the plant or to prevent spoilage of the product being processed.
Relief valve - A pressure relief device actuated by inlet static pressure having a gradual lift generally proportional to the increase in pressure over opening pressure.
Relief valves are commonly used in liquid systems, especially for lower capacities and thermal expansion duty. They can also be used on pumped systems as pressure overspill devices.
Safety relief valve - A pressure relief valve characterised by rapid opening or pop action, or by opening in proportion to the increase in pressure over the opening pressure, depending on the application, and which may be used either for liquid or compressible fluid.
In general, the safety relief valve will perform as a safety valve when used in a compressible gas system, but it will open in proportion to the overpressure when used in liquid systems, as would a relief valve.
Safety valve- A valve which automatically, without the assistance of any energy other than that of the fluid concerned, discharges a quantity of the fluid so as to prevent a predetermined safe pressure being exceeded, and which is designed to re-close and prevent further flow of fluid after normal pressure conditions of service have been restored.
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.