How does the cryogenic valve work？

Cryogenic valve such as Cast Iron Gate Valve refers to the valve can be used  for low temperature conditions, usually the valve will be regarded as cryogenic  valve when the operating temperature will be lower than -40 degrees c cryogenic  valve is usually used for oil and gas, air separation, natural gas industry,  etc., if it can work the quality determines the safety, economy, continue. With  the development of modern technology, the demand for cryogenic valves is  increasing and the range of use is increasing.

For temperatures above -50 degrees, do not use extended stem generally, for  temperatures below -50 degrees, the length of the extended stem depends on the  specific temperature. Cryogenic valve is mainly used for transmission like  ethylene cryogenic medium, liquid oxygen and liquid hydrogen, liquefied natural  gas, liquefied petroleum, etc., not only easy to explode, flammable, but also  become a gas in the temperature, gasification, volume will expand hundreds of  times.

Cast Iron Gate Valve Manufacturer thinks the low temperature valve material  is very important, if not correct, will lead to the valve body shell and sealing  surface inside and outside leakage, parts of the comprehensive mechanical  ability, strength and hardness is not qualified, will cause fracture. If the  liquefied natural gas leaks, it will explode. Therefore, material is the main  problem in the design and manufacture of LNG valves. The valve body and bonnet  consist of LCB (-46 Deg C), LC3 (-101 Deg C), CF8 (SS304) (-196 Deg C).

Long stem cryogenic valve designed to reduce heat from outside into the  valve; And ensure that the packing gland temperature above 0 degrees Celsius,  ensure that the packing is not affected; Finally, it prevents the stem and parts  above the bonnet from freezing or frosting as packing temperatures drop.

Commonly Used Metal Material For Valve(part1)

Commonly used valve metal materials are: commonly used electric valve metal materials ;commonly used pneumatic valve metal materials

It is not enough to know only the overall structure of the valve from Cast Iron Check Valve Supplier, but also the components and materials of the valve, so as to deepen the understanding of the valve.

In this chapter, ordinary valve body and cover, closure, stem and other three parts are introduced. Valve classification can be divided from the function, material, structure, pressure, diameter, connection, transmission mode, through the valve material to partition is a common classification. According to the material of valve body, the valve can be divided into metal valve, non-metal valve and metal valve body lining valve. And the metal valve is a common zui valve, is also a common zui valve.

Metal valve,it is to show valve body wait for a part to be made by metal material material valve, if Cast Iron Stop Valve, Cast Steel Gate Valve, copper ball valve.

Common valve material is carbon steel, C I1Cr5Mo chrome molybdenum steel, HCr13 is stainless steel, malleable cast iron, K L aluminum alloy, P0Cr18Ni9 is stainless steel, PL00Cr19Ni10 is stainless steel, Q nodular cast iron, R0Cr12Ni12Mo2 is stainless steel, RL00Cr17Ni14Mo2 is stainless steel, S body and cover is too big to the valve, it has to bear the pressure of medium, to adapt to a lake in the temperature range, has certain corrosion resistance, so it determines the weight of a valve and fuel economy, tend to consider when choosing materials.

Common Materials And Conditions Of Use For Valve Sealing Rings

The knowledge of valve sealing ring material is not enough, fast, afraid of trouble, violation of operating procedures, it is easy to cause problems in the installation of sealing ring above, resulting in more serious consequences. Sealing materials include metal materials (aluminum, lead, indium, stainless steel, etc.), as well as non-metal materials (rubber, plastics, ceramics, graphite, etc.), composite materials (such as rubber-asbestos board, aerogel felt - polyurethane), but rubber elastomer materials are the most commonly used.

Valve sealing materials from China Casting Valve Manufacturers in its form is divided into fluid sealing materials, non-fluid sealing materials, dynamic sealing and static sealing four categories, can withstand the joint displacement to achieve the purpose of air-tight, water-tight and embedded in the building joints in the shape and shape of the material.

Common materials and conditions of valve sealing ring materials are as follows:

1. Synthetic rubber: synthetic rubber is superior to natural rubber in oil, temperature and corrosion resistance. Temperature t 150 ℃ or less general synthetic rubber, natural rubber t 60 ℃ or less and rubber is used in the nominal pressure of PN 1 mpa or less cut-off valve, gate valve, diaphragm valve, butterfly valve, check valve, pipe valve seal valve, etc.

2. Nylon: nylon has the characteristics of small friction coefficient and good corrosion resistance. Nylon for t temperature of 90 ℃ or less more, nominal pressure PN acuities were 32 mpa ball valve, stop valve, etc.

3. Ptfe:ptfe for t temperature of 232 ℃ or less, nominal pressure PN 6.4 MPa or less cut-off valve, gate valve, ball valve, etc.

4. Cast iron, cast iron used for temperature t 100 ℃ or less, nominal pressure PN 1.6 MPa, gas and oil or less use of gate valves, globe valves, plug valves, etc.Such as Cast Iron Check Valve.

5. Babbitt, babbitt used for temperature t - 70 ~ 150 ℃, nominal pressure PN 2.5 MPa or less ammonia with globe valve.

6. Copper alloys: copper alloys commonly used materials are 6-6-3 tin bronze and 58-2-2 manganese brass. Copper alloy good abrasion resistance, suitable for temperature t 200 ℃ or less, nominal pressure PN 1.6 MPa in the water and steam, or less commonly used in gate valves, globe valves, check valves, plug valves, etc.

Causes Of Failure And Damage Of Stainless Steel Globe Valves

Failure and damage of Carbon Steel Stainless Steel Globe Valves, pipe threaded connections installed between valve. Rotation and thread side, hexagon and octagonal parts can not use a wrench directly acting on the moon shell. The control ability and the size of the pipe end of the water separator should be avoided. Product configuration and hard construction is a kind of pipeline damage.

For sundries in the pipeline to increase water resistance, at the same time to destroy the sealing of valves and fittings is in the pipeline and the inlet filter. Adjust the valve and automatic valve, after the automatic exhaust and installation between the reducing valve and the electric valve, also need to read the manual carefully, according to the requirements of the relevant debugging.

Butterfly valve from Cast Iron Butterfly Valve Suppliers and stainless steel globe valve to the excessive speed, water hammer effect. Valve and pressure should be increased, several times may damage the pipe fittings and valve, must pay attention to the pipeline pressure and temperature fluctuations. Reduced service life of valves and fittings should be avoided.

Analysis of China Casting Valve Manufacturers to choose valves to pay attention to what point

In recent years, the China Casting Valve Manufacturers realized the valve unattended strong automatic control, so the quality of the valve manufacturers to choose the valve to pay attention to which point?

I. parameters and specifications

So-called the parameters of the valve specifications can also be in short calls it the types of products, the principle of the valve consistent but the details are different, so is applicable to different places, such as the valve manufacturer of fire dampers in the mainstream of 3 c contains smoke fire damper and automatic smoke fire damper and so on all sorts of types, main control parameters and specification is the basis of choosing fire damper.

Ii. Applicable place and operating temperature

Cost-effective Cast Iron Gate Valve Manufacturer product identification will be clearly marked in the product operating temperature, it will directly determine its application, some inexpensive valve has certain versatility and generality, but as far as possible choose to install it in the main area, such as public buildings action temperature of fire dampers in exhaust system is relatively high, and the ordinary residential or commercial air conditioning system of action temperature of fire dampers in the 3 c is relatively low.

Iii. Functional requirements

For valve factory valves in the same product in different places have different requirements, so you choose 3 c before either from above or below the line of fire dampers in the choose and buy depends on its basic function and the applicable scope, such as fire damper, for example, still depends on whether you need 3 c fire valve has the function of automatic open and close, whether can meet the needs of normally open, if there is a remote control and signal output, and other functions.