What are the names of valves and give examples

Here are some of the well-known brands recognized in the valve industry, which are widely recognized and have a high reputation. While rankings may vary depending on time and market conditions, the following brands are generally considered to be among the top brands in the valve industry:

The following are the top ten domestic first-line valve brand manufacturers in 2022-2023, but for reference only: Suzhou Neway Valve Co., Ltd., Shanghai Guanlong Valve Machinery, Shanghai Qizhong Valve Manufacturing, Sanhua, Su Yan, Shentong, Su Valve, Nanfang, Jiang.

First, the word Yao. The above manufacturers are only estimates and references, and the specific situation may vary or fluctuate at any time due to changes in a series of factors such as changes in the market, the size of the competition pattern, and the stability of product quality. As an indispensable key device in industrial production and civil facilities, the quality and reputation of the valve brand directly affect the satisfaction and trust of users.

These brands are known in the valve industry for their innovative technology, high-quality products and reliability. It is important to note that the market and industry are evolving rapidly, and different rankings may vary depending on time and region. For the most up-to-date ranking information, it is recommended to refer to industry reports, professional organizations or market research data for more detailed and accurate information.

Valve is just a general term for the control components in the fluid transportation system, which can be divided into several categories, commonly used butterfly valves, ball valves, globe valves, gate valves, filters, balance valves, safety valves, etc., and are subdivided into manual, electric, pneumatic, etc., according to the connection method, it will be divided into several categories, clamps, flanges, quick assembly, ferrules, bonding, etc., so if you need a valve, you must be clear about what category the valve belongs to, and there must be specific parameters.

Valves have different names according to different structures and functions.

Common gate valves, globe valves, check valves, ball valves, butterfly valves, regulating valves, pressure reducing valves, safety valves, trap valves, diaphragm valves, plug valves, sewage valves, plunger valves, etc.

Valves are widely used and varied, and the difficulty of valve classification is also increasing, so let's take a detailed look at the types and characteristics of valves.

The type of valve.

Ball valve Ball valve is a kind of valve with a ball as a shut-off part, mainly composed of a valve body, a valve seat, a ball, a valve stem, a handle (or other driving device). It is driven by the valve stem and rotates around the axis of the ball valve. It is mainly used in the pipeline to cut off, distribute and change the flow direction of the medium.

For a wide variety of ball valves, including the principle of action, the medium and the different application sites, the user should choose different types of ball valves according to the requirements, and the types of ball valves are classified according to the actual working conditions on site.

Butterfly valve Butterfly valve can be divided into offset plate type, vertical plate type, inclined plate type and lever type according to the structural form. According to the sealing form, it can be divided into two types: relatively sealed type and hard sealed type. Soft-seated butterfly valves are generally sealed with rubber rings, and hard-sealed butterfly valves are usually sealed with metal rings.

According to the connection type, it can be divided into flange connection and clamp connection, and can be divided into manual, gear transmission, pneumatic, hydraulic and electric according to the transmission mode.

Gate valve Gate valve, also known as gate valve, is mainly composed of valve body, valve cover, gate, valve stem, valve seat and sealing packing, and is one of the most common valve types in isolation valves. The main purpose of a gate valve is to cut off the fluid, and it is for this reason that it is often referred to as a "cut-off" valve or a "block" valve. There are many different structural forms of gate valves, and the types of sealing elements used in them are different.

Depending on the structure of the sealing element, it can be divided into several different types. Shut-off valves.

Globe valve, also known as cut-off valve, is the most widely used valve, which is mainly composed of valve body, valve disc, valve cover, valve stem, etc. The valve body and bonnet are pressure-bearing parts, and the valve disc and valve stem are internal parts. A globe valve is a valve in which the shut-off (disc) moves along the centerline of the valve seat.

Depending on this form of disc movement, the change in the seat port is proportional to the disc stroke. Precautions for valve use.

Why is it easy for the double-seat valve to oscillate when working with a small opening?

For a single core, when the medium is a flow-open type, the valve has good stability; When the medium is a flow-closed type, the stability of the valve is poor. The double-seat valve has two spools, the lower spool is in the flow closed, and the upper spool is in the flow open, so that when the small opening is working, the spool of the flow closure type is easy to cause the vibration of the valve, which is the reason why the double-seat valve can not be used for small opening work.

Why is the stem of a linear control valve thinner?

It involves a simple mechanical principle: high sliding friction and low rolling friction. The stem of the linear valve moves up and down, and the packing is slightly compressed, which will wrap the stem very tightly, resulting in a large return difference.

For this reason, the valve stem is designed to be very small, and the packing is often used with a small friction coefficient PTFE packing to reduce the backlash, but the problem is that the valve stem is small, it is easy to bend, and the packing life is also short. To solve this problem, the best way is to use the travel valve stem, that is, the angle stroke type of control valve, its rapid opening valve stem is 2 3 times thicker than the linear stroke valve stem, and the use of long life of acres such as graphite packing, the stem stiffness is good, the packing life is long, and its friction torque is small, and the return difference is small.

<>1. There are 4 kinds of valve materials: gray cast iron, malleable cast iron, ductile iron, and nickel cast iron.

2. Gray cast iron refers to cast iron with flake graphite, which is called gray cast iron because the fracture is dark gray when fractured. The main components are iron, carbon, silicon, manganese, sulfur and phosphorus, which is the most widely used cast iron, and its output accounts for more than 80% of the total cast iron output.

3. Malleable cast iron, which is made of molten iron of a certain chemical composition poured into white blanks, and then annealed into cast iron, has high strength, plasticity and impact toughness, and can partially replace carbon steel.

4. Ductile iron is a high-strength cast iron material developed in the fifties of the 20th century, and its comprehensive properties are close to steel.

5. The metallographic structure of nickel cast iron is spherical graphite distributed on the austenitic body containing a small amount of carbide, so it has good high temperature resistance, corrosion resistance and wear resistance.

Composition: The valve is composed of two parts: actuation and actuation. The driving part comprises a driving device, a transmission component, a valve stem, etc.; The executive part includes the valve body, bonnet, opening and closing parts, etc.

The valve is a control component in the fluid transportation system, which has the functions of shut-off, regulation, diversion, preventing backflow of the ear, stabilizing pressure, diverting or overflow pressure relief. Valves for fluid control systems range from the simplest shut-off valves to those used in the most complex automation systems. Valves can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, slurries, oils, liquid metals and radioactive media.

As we all know, the air intake system of protective ventilation is set up next to the secondary entrance, and the entrance and exit of the dust and filtration room are set in a closed passage, separated by a closed door. Because the closed passage can only be closed and isolated to achieve the purpose of anti-virus, so in the case of outdoor poisoning, the protective closed door or closed door of the closed channel shall not be opened - this brings a problem: when the ventilation mode needs to be converted from clean to isolated or from isolated to filtered when the outdoor is poisoned, how should the staff operate the closed valve in order to safely realize the conversion of the ventilation mode.

It is understood that the closed valves on the market of protective products can be divided into two types: manual closed valves and manual electric closed valves according to the driving mode. Manual type airtight valves can only be realized by manually operating the handle...

Cut-off valves are mainly used to cut off or turn on the flow of media. Including gate valves, globe valves, diaphragm valves, ball valves, plug valves, etc

Disc valves, piston valves, ball plug valves, needle instrument valves, etc.

Control valves are mainly used to regulate the flow and pressure of the medium. Including regulating valves, throttle valves, pressure reducing valves, etc.

Check valves are used to stop the backflow of media. Check valves of various constructions are included.

Diverter valves are used to separate, distribute, or mix media. Including distribution valves and traps of various structures.

Safety valves are used for safety protection in case of overpressure of the medium. Various types of safety valves are included.

Classified by main parameters.

a) Classification by pressure.

Vacuum valve A valve whose working pressure is lower than the standard atmospheric pressure.

Low pressure valve A valve whose nominal pressure pn is less than.

Medium Pressure Valve A valve with a nominal pressure of pn.

High Pressure Valve A valve with nominal pressure.

Ultra-high pressure valve A valve with a nominal pressure pn greater than 100MPa.

2) Classification according to the temperature of the medium.

High temperature valve T > 450C valve.

Medium temperature valves 120 C less than t less than 450 C valves.

Normal temperature valves -40 C less than t less than 120 C valves.

Cryogenic valves -100 C less than t less than -40 C valves.

Cryogenic valves T Valves less than -100 C.

3) Classification according to the material of the valve body.

Non-metallic material valves: such as ceramic valves, FRP valves, plastic valves.

Metal material valves: such as copper alloy valves, aluminum alloy valves, lead alloy valves, titanium alloy valves, Monel alloy valves.

Cast iron valves, carbon steel valves, cast steel valves, low alloy steel valves, high alloy steel valves.

Metal body lined valves: such as lead-lined valves, plastic-lined valves, enamel-lined valves.

Common Taxonomy.

This classification method is divided according to principle, function and structure, and is the most commonly used classification method at home and abroad. General points.

Gate valves, globe valves, throttle valves, instrument valves, plunger valves, diaphragm valves, plug valves, ball valves, butterfly valves, check valves, pressure reducing valves.

Safety valves, steam traps, regulating valves, foot valves, filters, blowdown valves, etc.