Introduction to the working principle and structure of high pressure globe valve What are the advant

There are certain restrictions on everything that people can control freely, and pipes are no exception, and valves can be used for both liquid and gas flows.

to control. The flow of substances is different, the valve used is also different, the high-pressure shut-off valve is a kind of high-pressure work used in the valve. The main function of the high-pressure shut-off valve is actually a control function, which is used to control the flow of materials in the pipeline.

Due to its frequent use, people should understand its working principle and structure.

Introduction to high-pressure shut-off valves

A high-pressure 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. This type of valve is very suitable for regulating the flow rate because the stem opening or closing stroke is relatively short, and because it has a very reliable shut-off function, and because the change of the seat port is proportional to the stroke of the disc.

Therefore, this type of valve is ideal for use as a shut-off or regulation as well as throttling.

Working principle and structure of high-pressure globe valve

The stem axis of the cryogenic globe valve is perpendicular to the seat sealing surface. The relatively short opening or closing stroke of the stem and the very reliable shut-off action make this valve ideal for use as a shut-off or adjustment and throttling of the medium.

Once the disc of the high-pressure globe valve is open, there is no longer contact between the seat and the sealing surface of the disc, and it has a very reliable shut-off action, which is very suitable for the use of medium shut-off or adjustment and throttling.

Once the high-pressure globe valve is in the open state, there is no longer contact between its seat and the sealing surface of the valve disc, so the mechanical wear of its sealing surface is small, because the seat and disc of most globe valves are relatively easy to repair or replace the sealing elements without removing the entire valve from the pipeline, which is important for valve and pipeline welding.

It is very suitable for the occasion of being a whole. The flow direction of the medium through these valves changes, so the flow resistance of the globe valve is higher than that of other valves.

Advantages of high-temperature and high-pressure globe valves

1. The structure is simple, and the manufacturing and maintenance are relatively convenient.

2. The working stroke is small and the opening and closing time is short.

3. Good sealing, small friction between sealing surfaces, and long service life.

The high-pressure globe valve is small in size, but the structure is not simple, and it will be easier to understand the structure in combination with its working principle. The high-pressure globe valve is usually used in places with high temperatures, so it can withstand high temperatures, and some people also call it a high-temperature and high-pressure globe valve, which shows how huge its performance is. The high-pressure globe valve has many advantages relatively speaking, which cannot be compared with other valves, and its working environment is special, which is also irreplaceable by other valves.

There are many precautions in the process of using high-pressure shut-off valves, and we need to know more.

Which is the best manufacturer of valves in Shanghai? There are many valve manufacturers in Shanghai, specifically which one is the best, in fact, it is very difficult, this depends on where you can evaluate it conveniently, each manufacturer produces different valve products, and the fields involved are also very different, for example, some are doing water systems, some are doing industrial systems, and industrial systems are divided into many fields, such as: electric power, chemical industry, petroleum, pharmaceuticals and many other fields.

Here is a brief introduction to a few companies, Shanghai Qizhong valve in the field of water system, Suzhou Neway valve, Shanghai Guanlong valve this unit is not bad, industrial valve field can also be.

Here are some of the well-known brands recognized in the valve industry, which are widely recognized and have a high reputation. Although the ranking may change due to time and market conditions, the following brands are generally considered to be one of the top brands in the valve industry: water system valves and industrial valves The following more influential first-line brands can be used as a reference, and the following are the top ten domestic first-line valve brand manufacturers in 2022-2023, but for reference only:

Suzhou Neway Valve, Shanghai Guanlong Valve, Shanghai Qizhong Valve, Sanhua, Suyan, 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.

1. The structure is simple, and the manufacturing and maintenance are relatively convenient.

2. The working stroke is small and the opening and closing time is short.

3. Good sealing, small friction between sealing surfaces, and long service life.

4. The fluid resistance is large, and the force required for opening and closing is large.

5. It is not suitable for media with particles, large viscosity and easy coking.

6. Poor adjustment performance. Hazelnut Electromechanical.

The globe valve is a tool that relies on the pressure of the valve bar to make the sealing surface of the valve disc and the sealing surface of the valve seat tightly fit and prevent the flow of the medium. According to the channel direction, the globe valve is divided into four types: straight-through globe valve, direct flow globe valve, angle globe valve, and plunger globe valve.

The globe valve, also known as the cut-off door, is one of the most widely used valves, and the reason why it is widely popular is that the friction between the sealing surfaces in the opening and closing process is small, relatively durable, the opening height is not large, the manufacturing is easy, and the maintenance is convenient, not only suitable for medium and low pressure, but also suitable for high pressure. The closing principle of the globe valve is to rely on the pressure of the valve stem to make the sealing surface of the disc and the sealing surface of the valve seat fit tightly to prevent the flow of medium. China's valve "three to give" has stipulated that the flow direction of the globe valve is all top-down, so there is directionality when installing.

The structure length of the globe valve is greater than that of the gate valve, and the fluid resistance is large, and the sealing reliability is not strong during long-term operation.

As one of the most important shut-off valves, globe valves play an important role in the aerospace field. As an important component of aerospace equipment, the globe valve realizes the functions of medium transportation, cut-off and regulation, and its sealing performance directly affects the safe and reliable operation of aerospace equipment. The influencing factors and influencing rules of typical globe valve sealing characteristics are studied, which has guiding significance for the structural design of valve sealing pairs, so as to improve the sealing performance and reliability of valves.

The working principle and characteristics of the globe valve.

The valve plays an important role in cutting off and throttling the medium in the pipeline where it is located, and the globe valve is an extremely important cut-off valve, and its sealing is by applying torque to the valve stem, and the valve stem exerts pressure to the valve disc in the axial direction, so that the sealing surface of the valve disc and the sealing surface of the valve seat are tightly fitted, and the medium is prevented from leaking along the gap between the sealing surfaces.

The sealing pair of the globe valve is composed of the sealing surface of the disc and the sealing surface of the valve seat, and the valve stem drives the disc to move vertically along the center line of the valve seat. In the process of opening and closing the globe valve, the opening height is small, easy to adjust the flow rate, and the manufacturing and maintenance are convenient, and the pressure is widely applicable.

Compared with another commonly used cut-off valve in industrial production, the alarm valve, in terms of structure, the globe valve is simpler than the former, which is convenient for manufacturing and maintenance. In terms of service life, the sealing surface of the globe valve is not easy to wear and abrasion, and there is no relative sliding between the valve disc and the seat sealing surface in the process of valve opening and closing, so the wear and abrasion of the sealing surface is smaller, so the service life of the sealing pair is improved, and the valve disc stroke is small in the fully closed process, and its height is smaller than that of the alarm valve. The disadvantage of the globe valve is that the opening and closing torque is large and it is difficult to realize the rapid opening and closing, because the flow channel in the valve body is relatively tortuous, and the fluid flow resistance is large, resulting in a large loss of fluid power in the pipeline.

(1) The structure of the high-pressure globe valve is simpler than that of the gate valve, and it is more convenient to manufacture and maintain.

2) The sealing surface is not easy to wear and scratch, and the sealing performance is good. During the opening and closing process, there is no relative sliding between the valve and the protruding surface of the valve body, so the damage and scratches are not serious, the sealing performance is good, and the service life is long.

3) The stroke of the valve disc is small when the valve is opened, and the height of the cut-off valve is smaller than that of the gate valve, but the structural length is longer than that of the gate valve.

4) The opening and closing moment is large, the opening and closing is laborious, and the opening and closing time is the main.

5) The fluid resistance is large, because the medium channel in the valve body is tortuous, the fluid resistance is large, and the power consumption is large.

6) Nominal pressure: When the medium flows in the direction of PN is less than or equal to 16MPa, the general flow is downstream, and the medium is upward from the direction under the valve disc.

Flowing; When the nominal pressure PN is greater than or equal to 20MPa, counterflow and medium driven valves are generally used. The valve is down and up.

flow to increase sealing capacity. When used, the globe valve medium can only flow in one direction and cannot change the flow direction.

7) When fully open, the disc is often corroded. The seat shaft of the globe valve is perpendicular to the protrusion of the seat. The relatively short opening and closing stroke of the seat and the very reliable cutting action make this gate valve suitable for media cutting. or cut-off regulation and throttling.

The high-pressure globe valve has a simple structure and is easy to manufacture and maintain. The working stroke is small and the switching time is short. Good sealing, small friction between sealing surfaces, long life.

However, the fluid resistance of the high-pressure globe valve is large, and the force required for opening and closing is large. It is not suitable for granular media with high viscosity and easy coking. Poor regulation performance.

The globe valve is a forced sealed valve, so it is widely used, and the role of the globe valve is said to be three points: cut-off, regulation, and throttling; It is also said that it is fully open and closed, so what are the functions of the globe valve and what is the working principle of the globe valve?

The role of the shut-off valve.

The opening and closing parts of the globe valve are plug-shaped discs, the sealing surface is flat or conical, and the disc moves in a straight line along the center line of the fluid. The movement form of the valve stem has a lifting rod type (the valve stem is lifted, and the handwheel is not lifted), and there is also a lifting and rotating rod type (the handwheel and the valve stem rotate and lift together, and the nut is located on the valve body).

The stem axis of the globe valve is perpendicular to the seat sealing face. The medium flow direction of the globe valve is changed from the top of the valve disc into the valve cavity, at this time, under the action of medium pressure, the force of closing the valve is small, and the force of opening the valve is large, the opening or closing stroke of the valve stem is relatively short, once the globe valve is in the open state, there is no longer contact between its valve seat and the sealing surface of the valve disc, so its sealing surface mechanical wear is small, and has a very reliable cut-off action. Since the seat and disc of most globe valves are relatively easy to repair or replace the sealing elements, there is no need to remove the entire instrument valve from the pipeline, which is very suitable for the occasion where the instrument valve and the pipeline are welded into one.

How the globe valve works.

Let's assume that there is a pipe with a lid, water flows from the bottom of the pipe and flows out in the direction of the nozzle, and the cover of the outlet nozzle is equivalent to the closing and balancing vertical closure of the stop valve.

The check valve relies on rotating the handwheel to make the valve stem rise and fall, and drive the valve disc to make a linear displacement parallel to the flow direction of the medium, so as to achieve the purpose of opening and closing. The handwheel rotates in a clockwise direction, and the working medium enters through the disc fluid and the channel below, at this time, the sealing force applied must be equal to or greater than the sum of the specific pressure generated on the sealing surface and the upward force of the medium.

When the globe valve is opened, the opening height of the disc is 25% of the nominal diameter 30%, the flow rate has reached the maximum, indicating that the valve has reached the fully open position. Therefore, the fully open position of the globe valve should be determined by the stroke of the disc.

Note: 1The shut-off valve allows the medium to flow in one direction only and is directional when installed.

2.The function of the globe valve is either 0 or 1, either through or not. In other words, the shut-off valve is only suitable for full opening and full closing, and it is not recommended to adjust and throttle.