What are the advantages and disadvantages of soft seal gate valves

The soft seal gate valve is a rubber-wrapped metal gate valve, the processing is relatively simple, the valve body is made of cast iron or ductile iron, and the outer surface is made of epoxy resin paint, which can meet the sanitary requirements of tap water and is often used in municipal domestic drainage pipelines. Due to the soft seal, the sealing performance is better, especially at low pressure.

The disadvantage is that due to the soft rubber seal, it can only be used for temperatures below 80 degrees, and it is not suitable for particles with particles, as long as the medium that may damage the rubber sealing surface cannot be used.

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.

If the caliber, material and pressure level are the same, the current market ** or soft seal gate valve is about 20-30% more expensive.

The difference between soft seal gate valve and hard seal gate valve:

1. The soft seal gate valve is suitable for non-corrosive gas-liquid medium at room temperature (80). Such as clean water, air, oil, water treatment sewage and other pipelines. And it has a good sealing effect, which can achieve almost zero leakage.

2. The hard seal gate valve is suitable for high temperature (425) with slightly corrosive gas liquid. Such as steam, heat transfer oil, sewage, petroleum, chemical, metallurgy, pipelines. It can have a certain degree of wear resistance.

3. The difference between soft seal gate valve and hard seal gate valve is that the sealing performance of soft seal is better than that of hard seal, but the temperature resistance and wear resistance of hard seal gate valve is better than that of soft seal gate valve.

Hard seal: The seal pair is called a metal material or other hard material on both sides"Hard sealed".This kind of seal has poor sealing performance, but it is resistant to high temperatures, wear, and has good mechanical properties.

Such as: steel + steel; Steel + Copper; steel + graphite; steel + alloy steel; (The steel here may also be cast iron, cast steel, alloy steel may also be hardfacing, sprayed alloys).

Soft seal: The two sides of the sealing pair are made of metal material on one side and the other side is an elastic non-metallic material"Soft seal".This kind of seal has good sealing performance, but it is not resistant to high temperature, easy to wear, and has poor mechanical properties.

Such as: steel + rubber; Steel + PTFE [wiki] polyethylene [wiki]; Wait.

Generally speaking, the soft seal seat is made of non-metallic materials with certain strength, hardness and temperature resistance, with good sealing performance and zero leakage, but the life and adaptability to temperature are relatively poor.

Hard seals are made of metal and have relatively poor sealing performance, although some manufacturers claim to have zero leakage.

Soft seals can not meet the process requirements for some corrosive materials, and hard seals can solve them!

These two seals can complement each other, the soft seal is relatively good in terms of tightness, but now the tightness of the hard seal can also meet the corresponding requirements!

The advantage of soft sealing is good sealing performance, and the disadvantage is that it is easy to age, wear and tear, and has a short service life.

Hard seals have a long service life, but the sealing performance is relatively worse than that of soft seals.

Generally, ordinary gate valves generally leak and are easy to rust, and the company introduces foreign advanced technology to produce soft seal gate valves. It overcomes the defects of poor sealing, elasticity fatigue and easy rust of general gate valves. The soft seal gate valve is a replacement product of the traditional gate valve, which uses the elastic ram to produce a slight amount of deformation to compensate for the effect of good sealing, and the valve has the significant advantages of light switching, reliable sealing, good elastic memory and long service life.

The valve body and bonnet of the soft seal gate valve are cast by precision casting method, which is formed at one time, and is no longer machined at all, and does not use sealing copper rings, saving non-ferrous metals;

There is no pit at the bottom of the soft seal gate valve, no accumulation of slag, and the failure rate of the gate valve opening and closing is low;

The soft seal lined valve plate has a uniform size and strong interchangeability.

First, the sealing material.

The elastic soft seal gate valve and the hard seal gate valve are the sealing materials of the valve seat, and the hard seal is precision machined with the valve seat material to ensure the matching accuracy with the valve core (ball), generally stainless steel and copper. Soft sealing means that the sealing material embedded in the valve seat is a non-metallic material, because the soft sealing material has a certain elasticity, so the processing accuracy requirements will be lower than that of hard sealing.

Second, the manufacturing process.

Due to a lot of chemical industry, the working environment of the machinery industry is more complex, many are high temperature and high pressure, the friction resistance of the medium is large, the corrosiveness is strong, now the technology has progressed, the use of various materials is better, and the processing and other aspects can keep up, so that the hard seal ball valve has been widely promoted. In fact, the principle of hard seal gate valve is the same as that of soft seal, but because it is a seal between metals, it is necessary to take into account the hardness relationship between metals, as well as working conditions, what medium to go, etc. Generally, it is required to do hardening, and the ball and the valve seat should be continuously ground to achieve a seal.

The production cycle of hard seal gate valve is long, the processing is more complicated, and it is not easy to do a good job of hard seal ball valve.

3. Conditions of use.

Soft seals can generally reach high seals, while hard seals can be high or low according to requirements; Soft seals need to be fireproof, because at high temperatures, the material of the soft seal will leak, while the hard seal does not have this problem; Hard seals can generally be made at very high pressures, but soft seals cannot; Due to the problem of the medium flowing, the soft seal cannot be used in some occasions (such as some corrosive media); Finally, hard-seal valves are generally more expensive than soft-sealed. As for the manufacturing, there is not much difference between the two, the main thing is the difference between the valve seats, the soft seal is non-metallic, and the hard seal is metal.

Fourth, in the selection of equipment.

The selection of soft and hard seal gate valves is mainly based on the process medium, temperature and pressure, the general medium contains solid particles or has wear or the temperature is higher than 200 degrees, it is best to choose a hard seal, the diameter is greater than 50 valves, the pressure difference of the valve is larger, and the torque of the opening valve should be considered when the torque is larger, and the fixed hard seal gate valve should be selected, regardless of the soft and hard seal, the sealing level can reach 6.

1. In terms of planning mechanism: the hard seal is the seal between metal and metal, and the sealing ball and valve seat are metal. The machining accuracy and skills are relatively difficult, and it is generally used in high pressure, generally more than 35MPa.

A soft seal is a seal between metal and non-metal, such as nylon PTFE, and the standard of manufacture is the same.

2. Sealing material: elastic soft seal gate valve and hard seal gate valve are the sealing materials of the valve seat, and the hard seal is precision machining of the valve seat material to ensure the accuracy of cooperation with the valve core (ball), generally stainless steel and copper. Soft sealing means that the sealing material embedded in the valve seat is a non-metallic material, because the soft sealing material has a certain elasticity, so the processing accuracy needs to be relatively low than the hard seal.

3. Manufacturing skills: due to the chaotic working environment of many chemical and machinery industries, many of them are high temperature and high pressure, and the friction resistance of the medium is large and corrosive. Nowadays, the skills have improved, the use of various materials is better, and the processing and other aspects can keep up, so that the hard seal ball valve has been widely promoted.

In fact, the principle of hard seal ball valve is the same as that of soft seal, but because it is a seal between metals, it is necessary to consider the hardness contact between metals, as well as working conditions, what medium to go, etc. Generally, it needs to be hardened, and the ball and seat need to be continuously ground to reach the seal. The production cycle of the hard seal ball valve is long, the processing is messy, and it is not easy to do a good job of the hard seal ball valve.

4. In terms of application conditions: soft seals can generally reach high seals, while hard seals can be high or low according to needs. Soft seals need to be fireproof, because at high temperatures, the material of the soft seal will leak, while the hard seal has no such doubt.

Hard seals can generally be made at very high pressures, but soft seals cannot; Soft seals cannot be used in some occasions due to the problem of the medium flowed (such as some corrosive media). Hard-seal valves are generally more expensive than soft-sealed.

As for the manufacturing, the two are not much different, the first is the difference between the valve seats, the soft seal is the wrong metal, and the hard seal is metal.

The soft ambush sealed gate valve mainly has the following characteristics:1The stainless steel oil circuit plate and the single-flow valve group rental soft seal gate valve are made of mechanical processing.

Casting method, one-time molding, no mechanical treatment, no sealing copper ring, saving rare metals; 2. There is no slag accumulation at the bottom end, and the failure rate of gate valve opening and closing is low. 3. The valve plate is lined with soft sealing plastic, with uniform specifications and strong compatibility mode. Therefore, stainless steel soft seal gate valve is the trend of the development of collapse and dry gate valve, and it is a valve that wants to be selected in the field of aquatic industry.

When opening and closing, just prevent moisture and don't tighten it. Opening and closing became more and more difficult, and the liner fell off. Most of the disc valves used in the aquaculture industry are stainless steel soft-sealed gate valves, but because the silicone ring is easy to be damaged during the installation of the gate valve, which endangers the sealing characteristics, many businesses have introduced metal material seals.

The gate valve replaces the plastic sealed gate valve. Because of the low elasticity of the seal, stainless steel soft-seal gate valves generally use axial force construction, especially three-dimensional axial force construction.

Soft seal gate valve is a new type of fluid control valve, which has been widely used due to its several advantages:

1.Good sealing: The soft nano-wheel seal gate valve adopts the combination of elastic material sealing surface and metal sealing surface, which can effectively avoid the occurrence of leakage.

2.Convenient maintenance: The parts of the soft seal gate valve can be used interchangeably, and the pipe can be replaced and repaired without dismantling, which greatly saves the maintenance time and cost.

3.Low fluid resistance: The soft seal gate valve adopts friction sealing, and the sealing surface does not produce excessive extrusion deformation, so the resistance of the fluid is small when passing through, which can reduce the energy consumption of pipeline transportation.

4.Wide range of applications: The soft seal gate valve is suitable for water, oil, gas and other media, with a wide range of working temperatures, and has a strong adaptability to rubber tomato.

5.Long life: The soft dense beam roll-seal gate valve adopts advanced technology and high-quality materials, which has good corrosion resistance and wear resistance, and has a long life.

To sum up, the soft seal gate valve is easy to use, simple to maintain, has good sealing, adaptability and durability, and can be widely used in liquid and gas control pipeline systems.