nuova general instruments safety valve made in china

Actuatech SPA produces a wide range of pneumatic actuators dedicated to the remote control of industrial valves. Their actuators are designed in accordance with international standards, suitable for use with all accessories for handling and control, with the maximum safety and suitability for corrosive environments or potentially dangerous areas. The use of Actuatech SPA pneumatic actuators is especially valued and required in industrial water treatment plants, river water purification and sea water desalination. Moreover, the use of their actuators extends into many areas of industry, among which the chemical, refineries, cooling units for industrial steel plants, mining, wood processing, power generation, oil and gas piping, food industries, and the marine sector. Actuatech SPA offers various types of actuators in aluminum, stainless steel or iron, with treatments of external protection in accordance with specific requests from different industrial sectors.

Pressure relief valves (safety relief valves) are designed to open at a preset pressure and discharge fluid until pressure drops to acceptable levels. The development of the safety relief valve has an interesting history.

Denis Papin is credited by many sources as the originator of the first pressure relief valve (circa 1679) to prevent overpressure of his steam powered “digester”. His pressure relief design consisted of a weight suspended on a lever arm. When the force of the steam pressure acting on the valve exceeded the force of the weight acting through the lever arm the valve opened. Designs requiring a higher relief pressure setting required a longer lever arm and/or larger weights. This simple system worked however more space was needed and it coud be easily tampered with leading to a possible overpressure and explosion. Another disadvantage was premature opening of the valve if the device was subjected to bouncing movement.

Direct-acting deadweight pressure relief valves: Later to avoid the disadvantages of the lever arrangement, direct-acting deadweight pressure relief valves were installed on early steam locomotives. In this design, weights were applied directly to the top of the valve mechanism. To keep the size of the weights in a reasonable range, the valve size was often undersized resulting in a smaller vent opening than required. Often an explosion would occur as the steam pressure rose faster than the vent could release excess pressure. Bouncing movements also prematurely released pressure.

Direct acting spring valves: Timothy Hackworth is believed to be the first to use direct acting spring valves (circa 1828) on his locomotive engine called the Royal George. Timothy utilized an accordion arrangement of leaf springs, which would later be replaced with coil springs, to apply force to the valve. The spring force could be fine tuned by adjusting the nuts retaining the leaf springs.

Refinements to the direct acting spring relief valve design continued in subsequent years in response to the widespread use of steam boilers to provide heat and to power locomotives, river boats, and pumps. Steam boilers are less common today but the safety relief valve continues to be a critical component, in systems with pressure vessels, to protect against damage or catastrophic failure.

Each application has its own unique requirements but before we get into the selection process, let’s have a look at the operating principles of a typical direct acting pressure relief valve.

In operation, the pressure relief valve remains normally closed until pressures upstream reaches the desired set pressure. The valve will crack open when the set pressure is reached, and continue to open further, allowing more flow as over pressure increases. When upstream pressure falls a few psi below the set pressure, the valve will close again.

Most commonly, pressure relief valves employ a spring loaded “poppet” valve as a valve element. The poppet includes an elastomeric seal or, in some high pressure designs a thermoplastic seal, which is configured to make a seal on a valve seat. In operation, the spring and upstream pressure apply opposing forces on the valve. When the force of the upstream pressure exerts a greater force than the spring force, then the poppet moves away from the valve seat which allows fluid to pass through the outlet port. As the upstream pressure drops below the set point the valve then closes.

Piston style designs are often used when higher relief pressures are required, when ruggedness is a concern or when the relief pressure does not have to be held to a tight tolerance. Piston designs tend to be more sluggish, compared to diaphragm designs due to friction from the piston seal. In low pressure applications, or when high accuracy is required, the diaphragm style is preferred. Diaphragm relief valves employ a thin disc shaped element which is used to sense pressure changes. They are usually made of an elastomer, however, thin convoluted metal is used in special applications. Diaphragms essentially eliminate the friction inherent with piston style designs. Additionally, for a particular relief valve size, it is often possible to provide a greater sensing area with a diaphragm design than would be feasible with a piston style design.

The reference force element is usually a mechanical spring. This spring exerts a force on the sensing element and acts to close the valve. Many pressure relief valves are designed with an adjustment which allows the user to adjust the relief pressure set-point by changing the force exerted by the reference spring.

The chemical properties of the fluid should be considered before determining the best materials for your application. Each fluid will have its own unique characteristics so care must be taken to select the appropriate body and seal materials that will come in contact with the fluid. The parts of the pressure relief valve in contact with the fluid are known as the “wetted” components. If the fluid is flammable or hazardous in nature the pressure relief valve must be capable of discharging it safely.

In many high technology applications space is limited and weight is a factor. Some manufactures specialize in miniature components and should be consulted. Material selection, particularly the relief valve body components, will impact weight. Also carefully consider the port (thread) sizes, adjustment styles, and mounting options as these will influence size and weight.

In many high technology applications space is limited and weight is a factor. Some manufactures specialize in miniature components and should be consulted. Material selection, particularly the relief valve body components, will impact weight. Also carefully consider the port (thread) sizes, adjustment styles, and mounting options as these will influence size and weight.

A wide range of materials are available to handle various fluids and operating environments. Common pressure relief valve component materials include brass, plastic, and aluminum. Various grades of stainless steel (such as 303, 304, and 316) are available too. Springs used inside the relief valve are typically made of music wire (carbon steel) or stainless steel.

The materials selected for the pressure relief valve not only need to be compatible with the fluid but also must be able to function properly at the expected operating temperature. The primary concern is whether or not the elastomer chosen will function properly throughout the expected temperature range. Additionally, the operating temperature may affect flow capacity and/or the spring rate in extreme applications.

Beswick Engineering manufactures four styles of pressure relief valves to best suit your application. The RVD and RVD8 are diaphragm based pressure relief valves which are suited to lower relief pressures. The RV2 and BPR valves are piston based designs.

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.

Certification: TS licensing A1, A2, B1, B2, API-6D, CE, ISO9001, ISO14001, OHSAS18001, TUV issued by the API 6FA gate valve, API607 ball valve fireproof test

Neway Valve is one of the leading manufacturers of butterfly valves in China. It has a world-class valve plant that covers an extensive valve program to meet the needs of clients.

Neway butterfly valves are available in a number of series including T Series for concentric butterfly valves, TB Series for double offset butterfly valves, and TC Series for triple offset butterfly valves. These valves are used largely in chemical, nuclear, offshore, power, oil and gas, mining, and air separation industry.

Chaoda Group Wenzhou E-business Co., Ltd is an entirely owned branch of the Chaoda Valves Group Co., Ltd to market and sell valves, forging, casting, flanging, gas meter, etc. The company has earned special titles such as “Zhejiang Famous Product,” “Zhejiang Famous Brand,” and “Zhejiang Exporting Famous Brand.”

Chaoda houses a variety of cryogenic valves that are suitable for many different industries. They feature cryogenic globe, butterfly, check, trunnion ball, floating ball, check, gate, and other valves.

Chaoda forged steel cryogenic lift check valve is immersed in liquid nitrogen (-196 degree C) for 2 to 6 hours, then returned to normal temperature during production. This cycle is repeated twice to ensure the valve’s cryogenic abilities are top-notch. The valve can be made of carbon steel, stainless steel, alloy steel, and duplex stainless steel. It can be operated manually, by gear, electrically, or pneumatically. The valve can be used with oil, chemicals, natural gas, petrochemicals, coal chemicals, and more.

Beijing Valve General Factory Co., Ltd, or BVMC,was founded in 1953. With more than six decades of experience in the industry, the company has earned the position of vice chairman of National Valve Industry Association.

Beijing Valve General Factory has more than 60 years of experience in valve design and manufacturing. The company is actively involved in many national projects and also exports valves to more than 70 countries and regions around the world.

Their cryogenic ball valve can be used in temperatures ranging from -196 to 121 degrees C. The valve can be used with LNG and liquid nitrogen and is fire-safe and anti-static. The valve stem is extended and has extra packing ensuring any anti-flow. You can operate the valve with a handwheel, worm wheel, electric actuator or pneumatic actuator.

The secretary - general of China valve co., ltd was invited to participate in the valve technology forum of Jiangsu province, and made a special report entitled " the development direction of the 13th five - year new product of valve industry ".

First, song secretary - general briefed the development of China"s valve industry. He said, " the twelfth five - year" period, China"s valve industry has a great development. According to statistics, in 2015, the country has the size of enterprises ( annual sales of more than million yuan enterprises ) total 1806. Total assets of 1948 billion yuan, up 2.01 % year - on - year; Production valve 994.11 million tons, up 1.32 % year - on - year; The main business income of RMB 2,566 billion yuan, up - 0.47 %; The total profit was 172 billion yuan, up - 5.78 % year - on - year. Profit rate 6.7 %; The price index of valve products is 98.5 %; Completed export delivery value billion yuan, up - 8. 58 % year - on - year. Among them, Jiangsu province produces 92 million tons of valve products, the main revenue of 544.01 million, up 4.84 % year - on - year, total profit of 40.94 billion, up - 2.55 %, the indicators are better than the national average.

Over the years, through the introduction of technology and digestion and absorption and independent development, and technological transformation, the industry has generally increased the level of product development, design and manufacturing. At present can produce more than 3000 models, more than 40,000 specifications of valve products. Parameter range: nominal size from dn3 to 8000; Pressure from vacuum to 600; Temperature from cryogenic - 196 ℃ to high temperature 1200 ℃; Varieties include gate valve, globe valve, throttle valve, plug valve, ball valve, butterfly valve, diaphragm valve, check valve, relief valve, pressure relief valve, steam trap and regulating valve, etc., total 12 categories. The overall level has reached the level of international middle developed countries, and a few products have reached or are close to the international advanced level. The testing means and test conditions for conventional valves have been met. Test bench for individual special valves, such as high temperature test, ultra low temperature test and safety valve full performance test bench for nuclear power plant ( steam emission 660 / h ), etc. have been completed.

In addition to some special valves, domestic valves can basically meet the various fields of national economy and infrastructure construction needs. In particular, in recent years, the valve localization of millions of kilowatts nuclear power plants has made a significant breakthrough, with the nuclear sufa technology industry co., ltd, Dalian high - height valve co., ltd and Shanghai valve plant co., ltd as a group of key enterprises have developed important nuclear grade valve products, of which the nuclear class globe valve, check valve, butterfly valve and the majority of gate valves realize the localization. The localization rate of nuclear valve has been increased from 6 % in 8 years to more than 75 %. The full welded pipeline ball valve ( 11 - 15 MPa, dn28 ″ - 48 ″ ) is developed for the valve enterprise represented by Chengdu Ride valve group, Wuzhou valve group and Shanghai resistance rice co., ltd, and 48 ″ fully welded pipeline ball valve can be fully realized domestically. The development of these new products fills the domestic gap, and some products have reached or are close to the world"s leading level.

Through the digestion and absorption of imported technology and independent research and development, especially after the " twelfth five - year" period, the production level and product quality of thermal power valves have been greatly improved, providing a large number of key valves for supercritical and ultra-supercritical thermal power units.

Products of F92, f91 and wb36 electric gate valves and high - pressure heater three - way valve, high - pressure exhaust valve, high pressure steam trap, small turbine exhaust pipe large caliber vacuum electric butterfly valve, reheater reduction of water control valve, water storage tank regulating valve and reheater safety valve that producted by Hadian group Harbin power station valve co., ltd, Henan Kaifeng high pressure valve co., ltd, Shanghai valve factory co., ltd, Shanghai Huaerde electric power plant, Nantong power station valve co., ltd, nanfang valve co., ltd, Huaxia valve co., ltd ,Shanghai automation instrument group automation instrument, seven factories and other enterprises have been successively applied to Jiangsu Nantong power plant, Jiangsu Jurong power plant, Henan Jiaozuo power plant, Chongqing Hechuan power plant, Wanzhou power plant and Changxing power plant, such as 1000 MW ultra supercritical thermal power plant, the operation is good, broke the high temperature and high pressure valve of China"s ultra - supercritical thermal power unit, all rely on imported situation, through the national energy bureau stage acceptance.

In recent years, centrum, Suzhou NUVE and River valve stock company take full advantage of the advantages of the financing platform of listed companies, actively explore the " horizontal expansion, vertical extension" of the industrial transformation road, in order to seek new investment opportunities and economic growth point. During the " twelfth five - year plan ", several companies successfully completed the issuance of stock projects, a total of more than 10 billion yuan for nuclear power valves, and other high-end valve capacity expansion project, to successfully seize a new round of high-end valve market, the realization of the" 13th five - year " strategic objectives laid the foundation.

Secondly, song secretary - general proposed the new product development and promotion application of the 13th five - year plan. He referred to products in the following areas:

Such as: the reheater safety valve, main steam gate valve, high pressure heater three-way valve, main steam safety valve and high-low pressure bypass control valve for the key valves of large ultra-supercritical thermal power units;

The main steam isolation valve, voltage regulator proportional spray valve, blasting valve, main steam safety valve and voltage regulator safety valve of the one million PWR primary steam pressure water reactor for large nuclear power station;

The large diameter high temperature high pressure hydrogenation valve of petrochemical and coal chemical valve, four - way bellows switch ball valve, high pressure wear resistant valve, pilot safety valve and ultra low temperature relief valve, etc.;

" 56" high pressure welded ball valve, forced sealing valves, high pressure cock valves, cryogenic ball valves for liquefied natural gas, cryogenic butterfly valves for liquefied natural gas and low temperature axial flow check valves for liquefied natural gas, etc. In addition, song secretary - general also specifically mentioned the development of high-end electromagnetic valve.