What is the difference between a turbine double eccentric hemispherical valve and a handle double ec

It is the difference between the drive, the turbine is driven by gears, which is easier to switch on, and the handle is pushed by an open threaded rod, which is more gravity.

The double eccentric hemispherical valve uses the eccentric valve body, the eccentric ball and the valve seat, and the valve stem is automatically centered in the common trajectory when the valve stem is rotated, and the closing process is tighter and tighter, so as to fully achieve the purpose of good sealing. The ball and seat of the valve are completely separated, which eliminates the wear of the sealing ring, overcomes the problem of constant wear of the traditional ball seat and the sealing surface of the ball, and the non-metallic elastic material is embedded in the metal seat, and the metal surface of the valve seat is well protected. This product is especially suitable for steel industry, aluminum industry, fiber, micro solid particles, pulp, coal ash, petroleum gas and other media.

Double eccentric hemispherical valve features.

1. Its structure adopts the principle of eccentric tightening to achieve the purpose of tightening, adjusting and closing through the transmission mechanism, the sealing pair is a metal surface ring with a hard surface contact seal, the double eccentric structure is located in the hidden ball room when the double eccentric structure is opened, the valve core is located in the hidden ball room, the flow section is large, and the valve core is not washed out, the valve core is not washed out when closed, and the valve core spherical surface is gradually along the valve seat when opened, which effectively removes the scaling obstacle and realizes reliable sealing. It is particularly effective for mixed-flow conveyance of two-phase mixed-flow solids that are prone to fouling precipitation.

2. The hemisphere of the valve is made of bimetal, and different alloys are welded on the base metal, and the valve seat is also welded accordingly after special treatment, and the sealing surface is combined into various types such as anti-corrosion, wear-resistant, high-strength, etc., to meet the needs of different occasions.

3. Tight sealing, zero leakage of harmful gases.

4. The valve core of the sealing pair is left with a compensation amount, and when the valve is worn, it is rotated a little when it is closed, so that it can be reliably sealed and prolong the service life. In addition, the user unscrews the compression nut and the valve seat is still available after adjustment or replacement, avoiding the drawbacks of scrapping the entire unit after the valve seal fails.

Due to the selection of different alloys (or combination balls) of surfacing welding, the bimetallic sealing pair can be used for wear-resistant, corrosion-resistant, high-temperature resistant and strict sealing conditions.

1. General valve: specification and model DN40600. It is suitable for sewage treatment, pulp, urban heating and other occasions with strict requirements.

2. Special valve for petrochemical industry: specification DN40600. It is suitable for all kinds of oil products such as heavy oil and weak corrosion and two-phase mixed-flow media in the chemical industry.

3. Gas valve: specification DN40600. It is suitable for the transmission control of coal gas, natural gas and liquefied gas.

4. Special valve for slurry: specification DN40600. It is suitable for industrial pipeline transportation with crystallization precipitation or fouling in liquid and solid two-phase mixed flow or chemical reaction in liquid transportation.

5. Special valve for coal fly ash slag: specification DN40600. It is suitable for the control of power plants, hydraulic slag removal or gaseous conveying pipelines.

Enforce the standard. Design: GB12237 89

Flange connection: GB steel).

Structure length: GB12221 89

Here are some 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 influential first-line brands of water system valves and industrial valves can be used as a reference, but for reference only: Suzhou Neway Valve, Shanghai Guanlong Valve, Shanghai Qizhong Valve, Sanhua, Chaoda, 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.

<> with the continuous development of the industry, the demand for ball valves, especially ball valves under high temperature and high pressure harsh working conditions, is increasing, and ball valves are required to have higher performance such as wear resistance, erosion resistance, high temperature resistance, and corrosion resistance. However, although the traditional full-bore ball valve and valve seat are surface hardened by surfacing welding and spraying technology, their service life, cost and performance still cannot meet the requirements of use, such as industrial silicon, coal chemical industry, blast furnace gas, gas and other harsh working conditions. The double eccentric hemispherical valve is a new product developed by absorbing the advantages of ball valves, V-shaped valves and orbital ball valves with different structures.

The ball valve adopts double eccentric sealing structure, which has low wear, small torque, good sealing performance and long service life. The valve seat and hemisphere are treated with a special hardening process, which is especially suitable for the requirements of wear resistance, erosion resistance, corrosion resistance and high temperature resistance under harsh working conditions.

2. Structural characteristics.

Hemispherical body The hemispherical body of the double eccentric hemisphere valve adopts double eccentric design, which has reliable sealing effect, instant disengagement, small torque and long service life. It can be used in harsh working conditions for conveying particulate media. Its structural principle is that the center line of the hemisphere and the center line of the valve stem offset size a, and the center line offset size b of the valve seat, when fully opened, the ball and the valve seat are completely disengaged, and there is a certain gap, the radius of rotation is divided into long radius and short radius, the tangent of the long radius rotation trajectory will form an angle with the sealing surface of the valve seat, when the valve is opened and closed, the hemisphere has a fade out of the valve seat surface (as shown in the figure when the opening is 10 °, the core has been completely detached) and the effect of gradual extrusion, As a result, the mechanical wear and abrasion between the seat and the hemisphere during opening and closing is reduced, and the service life is improved.

The working principle of the eccentric hemispherical valve: it relies on rotating the valve chain to make the valve unblocked or occluded. The ball valve switch is lightweight, small in size, can be made into a large diameter, reliable sealing, simple structure, easy maintenance, the sealing surface and the spherical surface are often in a closed state, not easy to be eroded by the medium, and have been widely used in various industries.

a. Opening process.

1. In the closed position, the ball is pressed on the valve seat by the mechanical pressure of the valve stem.

2. When the handwheel is turned counterclockwise, the valve stem moves in the opposite direction, and its bottom angular plane disengages the ball from the valve seat.

3. The stem continues to lift and interacts with the guide pin in the spiral groove of the stem so that the ball begins to rotate frictionlessly.

4. Until it reaches the fully open position, the valve stem is lifted to the limit position, and the ball rotates to the fully open position.

b. Closing process.

1 When closing, rotate the handwheel clockwise, the stem begins to descend and makes the ball leave the seat and start rotating.

2. Continue to rotate the handwheel, and the valve stem is affected by the guide pin embedded in the spiral groove on it, so that the valve stem and the ball rotate 90° at the same time.

3 When it was about to close, the ball had been rotated 90° without contact with the valve seat.

4. In the last few turns of the handwheel, the angular plane at the bottom of the stem is mechanically wedged to compress the ball so that it is tightly pressed against the valve seat to achieve a complete seal.

Eccentric hemispherical valves are divided into two types in terms of appearance and structure

1. Body-mounted type: mainly for the medium with very serious erosion and wear, the replacement and maintenance of the damaged opening and closing parts of the body-mounted structure is very convenient, and there is no need to remove the whole valve from the pipeline, which greatly saves the maintenance time and cost.

2. Side-mounted type: The side-mounted type has a compact structure and light valve weight, which is suitable for occasions where the valve installation space is required.

1. The fluid resistance is small, and its resistance coefficient is equal to that of the pipe section with the length of Tonghui tremor.

2. Simple structure, small size and light weight.

3. Tight and reliable, at present, the sealing surface material of the grinding ball valve is widely used plastic, with good sealing, and has been widely used in the vacuum system.

4. Easy to operate, fast opening and closing, from full open to full closed, as long as the rotation is 90°, which is convenient for long-distance control.

5. It is easy to maintain, the structure of the ball valve is simple, the sealing ring is generally movable, and it is more convenient to disassemble and replace.

6. When fully open or fully closed, the sealing surface of the ball and the valve seat is isolated from the medium, and when the medium passes, it will not cause the erosion of the noisy surface before the valve is sealed.

7. Wide range of application, from small to a few millimeters, as large as a few meters, from high vacuum to high pressure can be applied.