double safety valve supplier

Searching for tools to control the flow of your piping system? Explore one of the largest featured collections of products and discover a range of wholesale double safety valve on Alibaba.com. When you search for double safety valve and related items, you will be able to find many types of double safety valve varying in size, shape, use, and quality, all at prices in which are highly reasonable!

There are many uses of valves - mainly controlling the flow of fluids and pressure. Some examples include regulating water for irrigation, industrial uses for controlling processes, and residential piping systems. Magnetic valves like those using the solenoid, are often used in a range of industrial processes. Whereas backflow preventers are often used in residential and commercial buildings to ensure the safety and hygiene of the water supplies. Whether you are designing a regulation system for irrigation or merely looking for a new replacement, you will be able to find whatever type of double safety valve that you need. Our products vary from check valves to pressure reducing valves, ball valves, butterfly valves, thermostatic mixing valves, and a lot more.

Distributor of hydraulic press safety, quick opening safety, rotary and safety valves. Amerigear®, Boston Gear®, Carlisle®, DeMag®, Desch® and IMI Norgren®, pneumatic, double action, quick release and flow control valves also provided. Repair and preventative maintenance services are offered. Value added services such as custom barcoding, CAD capabilities, OEM assembly, plant surveys and third party logistics are also available. Serves the metal processing, metal service center, paper mill and paper converting, canning, grinding, commercial laundry, marine, oil and gas and material handling industries. Vendor managed inventory (VMI) programs available. Kanban delivery.

AWP valves and components are suitable for use with natural refrigerants, non-corrosive gases and liquids and cooling brine. These valves and components are perfectly designed, developed and manufactured in accordance with your specifications.

Maximum Safety in a double-poppet safety valve with two independent seals. The safest safety valve. Only Universal uses an independent shear section for easy replacement. No need to remove the top poppet as with competitive products. Also, no need to buy an expensive replacement poppet top. This reduces the chance of fire and contamination. This unique three piece design allows for two independent seals which increases safety and reduces future labor and replacement costs.

Maximum Safety in a double-poppet safety valve with two independent seals. The safest sfety valve. Only Universal uses an independent shear section for easy replacement. No need to remove the top poppet as with competitive products. Also, no need to buy an expensive replacement poppet top. This reduces the chance of fire and contamination. This unique three piece design allows for two independent seals which increases safety and reduces future labor and replacement costs.Application -

✔Pressure relief (upper poppet) to prevent pressure build-up✔Both poppet and seats are completely independent of the shear section, so when sheared the valve assures a 100% liquid tight seal✔The single link design provides ease of operation and reduced maintenance✔An air test port allows line testing without breaking the integrity of the line✔Raised bosses provide secure anchoring✔Optional model 522DP with 2” external male threads for easy connection to secondary containment pipingConstruction -

Industry leading pressure and safety relief valve designs with over 140 years of technical and application expertise providing custom engineered solutions for O&G, Refining, Chemical, Petrochemical, Process and Power applications. Our designs meet global and local codes and standards (API 526; ASME Section I, IV & VIII; EN ISO 4126; PED & more). Gain insight into the performance of your pressure relief valves with wireless monitoring.

Emergency situations are not the only times relief valves are active; once installed they continuously regulate the flow of substance. They can also be pre-set to open when the pressure or temperature gets to a certain point that may be dangerous. Generally valves are placed on or near the pump head of the hose, pipe or tube. A wide variety of relief valve designs exist, although most resemble ball-check valves, swing check valves or diaphragm valves.

This last is particularly useful when controlling a flow of fluids that contains suspended solids. Most relief valves are spring operated, as are the majority of check valves. One specialized type of relief valve is known as a vacuum relief valve. As opposed to a normal relief valve, which relieves high pressure, a vacuum relief valve is used to relieve dangerously low pressures, or vacuums, by inserting air or an inert gas.

Like every other type of check valve, relief valves may be constructed from a variety of materials, including PVC, brass, ductile iron, copper, polyethylene, polypropylene, aluminum, steel, stainless steel and rubber. Which raw substance is used to produce each relief valve depends on the environment said relief valve will be in. The wrong product could result in erosion or contamination of the process stream. However, as long as research is done, finding the appropriate type of relief valve is possible. Every plumbing or fluid transfer application in the industrial, commercial and domestic arenas employ or will employ check valves. In fact, check valves of all kinds are an essential part of every day life. Because they need not be supervised to function and prevent product malfunction, check valves are not only desirable but often required by law to ensure the safety of water, gas and pressure applications.

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ValveCast Iron Diaphragm ValveCasting Trunnion Ball Valvecheck valveConnection Lift Plug ValveControl ValveCryogenic Ball ValveCryogenic Check ValveCryogenic Emergency Cut off ValveCryogenic Gate ValveCryogenic Globe ValveCryogenic Long Stem Globe ValveCryogenic Pneumatic Actuated Globe ValveCryogenic Short Stem Globe ValveCryogenic Steam Jacket Globe ValveCryogenic ValveDiaphragm ValveDIN Globe ValveDIN Non Rising Stem Ductile Iron Gate ValveDIN Non Rising Stem Gate ValveDIN NRS Cast Iron Gate ValveDIN Rising Stem Cast Iron Gate ValveDIN Rising Stem Ductile Iron Gate ValveDIN Rising Stem Gate ValveDIN Soft Seat Gate ValveDirect Acting Pressure Reducing ValveDouble Block and Bleed Ball ValveDouble Disc Gate ValveDouble Eccentric Butterfly ValveDouble Offset Butterfly ValveDouble Orifice Air Release ValveDouble Orifice Kinetic Air ValveDual Plate Lug Check ValveDual Plate Wafer Check ValveDuctile Iron Diaphragm ValveDuplex 1B 3 PC Ball ValveDuplex 3 Piece Ball ValveDuplex Basket 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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.

Consolidated boasts 140+ years of dedicated Pressure Relief Valve (PRV) Engineering and Manufacturing expertise.  We know overpressure protection!  With more than 10 major first-to-market products and features, Consolidated continues to deliver innovative technical solutions to the world"s most challenging overpressure protection applications.  When combined with the expertise and full-scale service of the Green Tag Center (GTC) Network, Consolidated is able to provide a comprehensive approach to Valve Lifecycle Management (VLM) that is second to none.

Comprehensive Valve Lifecycle Management (VLM) enabled by state-of-the-art tools and delivered by the unparalleled Consolidated Green Tag Center (GTC) Network, Consolidated supports our product throughout the entire lifecycle.

Combination water meters comprises of a bulk Woltmann insert and a low-flow Volumetric insert or meter, flow is diverted between them by a by-pass valve that is set at a predetermined flow rate. This allows the combination meter to have a very large measurement range.

Whole products such as valves, boilers & showers undergo mechanical and water quality testing. This type of approval demonstrates full compliance with the requirements of the regulations and bye-laws, provided the fitting is installed according to any conditions given with the approval.

BS EN 331:2015 specifies the characteristics for the construction, performance and safety of ball valves and closed bottom taper plug valves. It also details the test methods and marking provisions. It applies to metallic valves not directly buried for domestic and commercial installations inside or outside of buildings, using gases of the first, second and third family (specified in EN 437) and working up to 0,2 × 105 Pa, 0,5 × 105 Pa, 1 × 105Pa, 5 × 105 Pa and 20 × 105Pa and with temperature limits from – 5 °C or -20 °C to + 60 °C.

Classification, verification, risk management, and technical advisory to the maritime industry on safety, enhanced performance, fuel efficiency, etc. As a classification society, DNV GL sets standards for ships and offshore structures – known as Class Rules. They comprise safety, reliability and environmental requirements that vessels and other offshore mobile structures in international waters must comply with. DNV GL is authorized by 130 maritime administrations to perform certification or verification on their behalf.

Valves have been qualified by testing to API standards 607, 4th Edition. The valve design incorporates a secondary metal seat in the body, providing the required shutoff should the primary seats be destroyed by fire.

Many of our marine valves can be pressure tested, witnessed by a classification society and supplied with 3.1 & 3.2 certifications on request, these include Lloyd’s Register of Shipping, DNV-GL (Det Norske Veritas), RINA, Bureau Veritas, Germanischer Lloyds, NK and ABS (American Bureau of Shipping). Please contact sales with your requirements.

Prevent dangerous spikes in pressure with a pneumatic safety valve. They are designed for safety of your system and maintenance of optimal system performance.

Curtiss-Wright"s selection of Pressure Relief Valves comes from its outstanding product brands Farris and Target Rock. We endeavor to support the whole life cycle of a facility and continuously provide custom products and technologies. Boasting a reputation for producing high quality, durable products, our collection of Pressure Relief Valves is guaranteed to provide effective and reliable pressure relief.

While some basic components and activations in relieving pressure may differ between the specific types of relief valves, each aims to be 100% effective in keeping your equipment running safely. Our current range includes numerous valve types, from flanged to spring-loaded, threaded to wireless, pilot operated, and much more.

A pressure relief valve is a type of safety valve designed to control the pressure in a vessel. It protects the system and keeps the people operating the device safely in an overpressure event or equipment failure.

A pressure relief valve is designed to withstand a maximum allowable working pressure (MAWP). Once an overpressure event occurs in the system, the pressure relief valve detects pressure beyond its design"s specified capability. The pressure relief valve would then discharge the pressurized fluid or gas to flow from an auxiliary passage out of the system.

Below is an example of one of our pilot operated pressure relief valves in action; the cutaway demonstrates when high pressure is released from the system.

Air pressure relief valves can be applied to a variety of environments and equipment. Pressure relief valves are a safety valve used to keep equipment and the operators safe too. They"re instrumental in applications where proper pressure levels are vital for correct and safe operation. Such as oil and gas, power generation like central heating systems, and multi-phase applications in refining and chemical processing.

At Curtiss-Wright, we provide a range of different pressure relief valves based on two primary operations – spring-loaded and pilot operated. Spring-loaded valves can either be conventional spring-loaded or balanced spring-loaded.

Spring-loaded valves are programmed to open and close via a spring mechanism. They open when the pressure reaches an unacceptable level to release the material inside the vessel. It closes automatically when the pressure is released, and it returns to an average operating level. Spring-loaded safety valves rely on the closing force applied by a spring onto the main seating area. They can also be controlled in numerous ways, such as a remote, control panel, and computer program.

Pilot-operated relief valves operate by combining the primary relieving device (main valve) with self-actuated auxiliary pressure relief valves, also known as the pilot control. This pilot control dictates the opening and closing of the main valve and responds to system pressure. System pressure is fed from the inlet into and through the pilot control and ultimately into the main valve"s dome. In normal operating conditions, system pressure will prevent the main valve from opening.

The valves allow media to flow from an auxiliary passage and out of the system once absolute pressure is reached, whether it is a maximum or minimum level.

When the pressure is below the maximum amount, the pressure differential is slightly positive on the piston"s dome size, which keeps the main valve in the closed position. When system pressure rises and reaches the set point, the pilot will cut off flow to the dome, causing depressurization in the piston"s dome side. The pressure differential has reversed, and the piston will rise, opening the main valve, relieving pressure.

When the process pressure decreases to a specific pressure, the pilot closes, the dome is repressurized, and the main valve closes. The main difference between spring-loaded PRVs and pilot-operated is that a pilot-operated safety valve uses pressure to keep the valve closed.

Pilot-operated relief valves are controlled by hand and are typically opened often through a wheel or similar component. The user opens the valve when the gauge signifies that the system pressure is at an unsafe level; once the valve has opened and the pressure has been released, the operator can shut it by hand again.

Increasing pressure helps to maintain the pilot"s seal. Once the setpoint has been reached, the valve opens. This reduces leakage and fugitive emissions.

At set pressure the valve snaps to full lift. This can be quite violent on large pipes with significant pressure. The pressure has to drop below the set pressure in order for the piston to reseat.

At Curtiss-Wright we also provide solutions for pressure relief valve monitoring. Historically, pressure relief valves have been difficult or impossible to monitor. Our SmartPRV features a 2600 Series pressure relief valve accessorized with a wireless position monitor that alerts plant operators during an overpressure event, including the time and duration.

There are many causes of overpressure, but the most common ones are typically blocked discharge in the system, gas blowby, and fire. Even proper inspection and maintenance will not eliminate the occurrence of leakages. An air pressure relief valve is the only way to ensure a safe environment for the device, its surroundings, and operators.

A PRV and PSV are interchangeable, but there is a difference between the two valves. A pressure release valve gradually opens when experiencing pressure, whereas a pressure safety valve opens suddenly when the pressure hits a certain level of over pressurization. Safety valves can be used manually and are typically used for a permanent shutdown. Air pressure relief valves are used for operational requirements, and they gently release the pressure before it hits the maximum high-pressure point and circulates it back into the system.

Pressure relief valves should be subject to an annual test, one per year. The operator is responsible for carrying out the test, which should be done using an air compressor. It’s imperative to ensure pressure relief valves maintain their effectiveness over time and are checked for signs of corrosion and loss of functionality. Air pressure relief valves should also be checked before their installation, after each fire event, and regularly as decided by the operators.

Direct-acting solenoid valves have a direct connection with the opening and closing armature, whereas pilot-operated valves use of the process fluid to assist in piloting the operation of the valve.

A control valve works by varying the rate of fluid passing through the valve itself. As the valve stem moves, it alters the size of the passage and increases, decreases or holds steady the flow. The opening and closing of the valve is altered whenever the controlled process parameter does not reach the set point.

Control valves are usually at floor level or easily accessible via platforms. They are also located on the same equipment or pipeline as the measurement and downstream or flow measurements.

An industrial relief valve is designed to control or limit surges of pressure in a system, most often in fluid or compressed air system valves. It does so as a form of protection for the system and defending against instrument or equipment failure. They are usually present in clean water industries.

A PRV is often referred to as a pressure relief valve, which is also known as a PSV or pressure safety valve. They are used interchangeably throughout the industry depending on company standards.