The difference between cast iron gate valve and seated gate valve

The opening and closing parts of the cast iron gate valve are the gate plate, the direction of movement of the gate plate is perpendicular to the fluid direction, and the gate valve can only be fully opened and closed, and can not be adjusted and throttled. The ram has two sealing faces, and the two sealing faces of the most commonly used mode gate valve form a wedge-shaped and wedge-shaped angle valve. The cast iron gate valve is an automatic valve, and the sealing surface can only rely on the medium pressure to seal, that is, only rely on the medium pressure to press the sealing surface of the ram to the valve seat on the other side to ensure the sealing of the sealing surface, which is self-sealing.

Most gate valves are forcibly sealed, that is, when the valve is closed, the ram should be forced to the valve seat by external force to ensure the tightness of the sealing surface. The opening and closing parts of the seat seal gate valve are the gate, the direction of movement of the gate is perpendicular to the direction of the fluid, and the gate valve can only be fully opened and closed, and can not be adjusted and throttled. Seat seal gate valve is widely used in tap water, sewage, construction, petroleum, chemical, food, medicine, textile, electric power, shipbuilding, metallurgy, energy system and other fluid pipelines as a regulating and interception device, to solve the valve seat and valve plate after the sealing surface corrosion or deformation, the valve plate can automatically compensate and compress the cover and the pressure between the elastic seat seal gate valve automatic balance, to solve the problem of soft sealing material by friction and damage to the sealing surface, because the gate valve seal sleeve can be replaced, greatly increase the use of valves.

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 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, 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.

Summary. Hello, glad to come to your question, of course there is a certain difference.

The difference is that the form of the sealing surface of the ram is different.

Is there a difference between an elastic seated gate valve and an ordinary gate valve?

Hello, glad to come to your question, of course there is a certain difference.

The difference is that the form of the sealing surface of the ram is different.

Generally, gate valves are generally leaking and easy to rust. The elastic seat seal contains the Chanchun gate valve and the gate, and the material is cast iron lined with rubber. It overcomes the shortcomings of general plucking, such as poor sealing, fatigue of elasticity, and easy rusting.

I hope my answer will be helpful to you, and I wish you all the best.

The carbon steel gate valve is a cast steel gate valve, which is represented as Z41H-16C from the valve model

Carbon steel is carbon steel, including cast carbon steel, rolled carbon steel, forged carbon steel, etc.; Cast steel is a variety of cast steel parts obtained through casting methods, including cast carbon steel, cast alloy steel, etc.

The so-called cast steel and carbon steel are just the names produced by the different classifications of steel.

Many people will think that carbon steel gate valve and cast steel gate valve are 2 kinds of material valves, the following by Wenzhou Boyuan valve to analyze:

Cast steel check valve and carbon steel check valve are check valves of the same material, both of which are made of WCB A216 carbon steel.

Cast steel check valve, because the WCB material of the valve body, the blank are cast, so the name is Siyi, it is called cast steel check valve.

Carbon steel check valve, because the main material of WCB material is carbon steel, so it is named carbon steel check valve.

Cast steel has less carbon content, good toughness, and higher pressure and temperature resistance than cast iron. Cast iron valves are not suitable for diesel, seawater and acidic media. Cast iron valves are less expensive.

The valve (famen) is a control component in the fluid transfer system, which has the functions of shut-off, regulation, diversion, prevention of backflow, pressure stabilization, diversion or overflow pressure relief. Valves for fluid control systems range from the simplest shut-off valves to the most complex valves used in automated control 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. According to the material, the valve is also divided into cast iron valves, cast steel valves, stainless steel valves, etc.), chromium-molybdenum steel valves, chromium-molybdenum-vanadium steel valves, duplex steel valves, plastic valves, non-standard customized and other valve materials.

Cast iron is divided into ductile iron, malleable cast iron, and gray cast iron.

Ductile iron models with a Q on the back

Malleable cast iron models with a K on the back

The nominal pressure of gray cast iron is less than or equal to that of cast steel: carbon steel is greater than or equal to that of model preparation.

For the specific model preparation, please refer to JB T 308 (valve model preparation method).

Temperature resistant. Cast steel valves can withstand high temperatures, and cast iron valves cannot be used with water.

**, the properties of various materials are not the same.

They are made of significantly different materials and use them in different environments! The cost also has its own merits. In short, the specific situation is analyzed on a case-by-case basis.

1 spool.

The valve core of the ball valve is a ball, because of the structure of its fixed ball, the valve is fixed under the condition of high pressure, especially in the closed state, the valve ball is fixed, and the upper valve stem and the lower branch decompose part of the pressure from the medium, so the valve ball does not offset downstream, so the pressure borne by the downstream valve seat is relatively small, so the friction that the valve overcomes when the valve is small, the wear of the valve seat is small, and the service life of the valve is long, especially for the valve that often acts, this structure is more suitable.

The spool of a gate valve is a wedge-shaped disc or this parallel disc. Its lower part has no pivot. Therefore, when the valve is applied under high pressure and in the closed state, the valve plate bears a great pressure from the medium, and because of its flat valve plate structure, all the medium pressure acts on the valve plate at the same time, and the valve plate will be pressed to the downstream valve seat (at the same time, the excessive pressure acts on the vertical plane of the valve plate, which will make the valve plate whether it is a wedge or a parallel double gate, there will be a certain deformation), then the valve needs to overcome great friction when it is opened, and the wear of the valve seat prints the life of this valve is short.

2 seats. The ball valve has a spring inside the seat, and the sealing design of the seat makes it difficult for the residue in the medium to enter the seat. The valve seat is in contact with the valve ball for a long time under the action of the spring, so when the valve is moving, the valve seat has a certain scraper effect, which can scrape off the slag attached to the valve core after long-term operation, so the sealing performance of the valve can be guaranteed for a long time. Especially in the application of high temperature and high pressure, because the material of the valve seat, valve body and valve ball is selected with the same coefficient of thermal expansion when selecting, as well as the valve seat with spring structure, when the valve is closed, the huge temperature difference and the drop in temperature will not affect the action of the valve, and the valve will not produce the phenomenon of locking.

The seat of the gate valve is very narrow, and in high temperature applications, when the valve is closed, the temperature drops because the medium does not flow, so the seat will tighten, resulting in a large compression force on the valve plate. When the valve is opened again, a large torque is required to overcome this compressive force, which will cause great damage to the valve seat and affect the life of the valve seat. This affects the service life of the valve.

In addition, due to the weight of the ram itself when the valve is closed, it will bring a great impact force to the valve and make a lot of noise.

3 Itinerary. The ball valve has an angular stroke and therefore has a small installation space and low height.

The stroke of the gate valve is straight, so the installation space is large and the height is high.

4 Actuators.

Due to the fixed ball design, the torque value of opening and closing is small, so the actuator is correspondingly small. Due to the large compressive force of the valve plate on the valve seat, it is necessary to overcome this large friction force, and the actuator is equipped with a large torque.

5. The flow direction of the medium is double flow, and there is no installation flow direction problem on site. Generally, it is a single flow.

6. Long service life, short compared with ball valves.

7 Maintenance. Generally, there is no maintenance, especially the ball and seat, which do not need to be replaced within 5 years due to low wear.

Due to the high wear and tear of the seat, regular maintenance is required.

The ball valve relies on the ball in the valve body to intercept the fluid, and the sky closes relatively quickly. The gate valve is to rely on the ram to lift and drop to intercept the fluid, and the switch is slower. But with less effort.

Gate valve: suitable for use when [fully open] or [fully closed] is required, if it is used when [half-open], it may damage the valve body; It has the characteristics of maintaining a certain flow path area, small flow change of the valve body, and very little pressure loss when fully opened; In a fully enclosed state, it has excellent sealing performance.

Ball valve: It can be opened and closed at 90 degrees, and it is easy to operate. Suitable for use when fully open or fully closed.

Caution: Use in the half-open state, which may damage the valve body; The fluid performance is good, and the flow path and pipe diameter can be combined into one; Due to the use of PTEE sealant gaskets, the type and temperature of the fluid are somewhat limited.

Ball valves are more durable than gate valves, and after a long period of use, gate valves are prone to water leakage.

The ball valve is quarter-stroke and the ram is linear.

The ball valve relies on the ball in the valve body to intercept the fluid, and the sky closes relatively quickly. The gate valve is to rely on the ram to lift and drop to intercept the fluid, and the switch is slower. But with less effort.

The sealing surface of the ball valve is spherical.

The sealing surface of the gate valve is flat.

The ball valve has low flow resistance, and the gate valve is suitable for high-pressure and high-temperature pipes.

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