What material is the hard seal butterfly valve resistant to acid and alkali

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 the user's stove.

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 changing rapidly, and the rankings may vary by time and region. For the latest ranking information, it is recommended to refer to industry reports, professional institutions or market research data for more detailed and accurate information.

Abstract:The difference between hard seal butterfly valve and soft seal butterfly valve is mainly reflected in the structure, temperature resistance, pressure and sealing performance, among which in the temperature resistance comparison, the soft seal is used in the normal temperature environment, and the hard seal can be used in low temperature, room temperature, high temperature and other environments. Therefore, the scope of application of the hard seal butterfly valve is also relatively wide, and the scope of application includes furnaces, gas, steam, natural gas, city gas, hot and cold air, chemical smelting engineering and power generation environmental protection system, and the pipeline that transports various corrosive and non-corrosive fluid media.

Specifically, about the difference between hard seal butterfly valve and soft seal butterfly valve, and what is the scope of application of hard seal butterfly valve, let's take a look with me in the article! 1. The difference between a hard seal butterfly valve and a soft seal butterfly valve is in the first place.

If butterfly valves are divided according to the sealing form, they can be divided into metal hard seals and rubber soft seals. Let's take a look at the difference between hard seal butterfly valve and soft seal butterfly valve?

1. Structure: Soft seal butterfly valves are mostly centerline type hard seals, and most of them are single eccentric, double eccentric, and triple eccentric butterfly valves.

2. Temperature resistance: soft seal is used in normal temperature environment, hard seal can be used in low temperature, normal temperature, high temperature and other environments.

3. Pressure: soft seal low pressure-normal pressure, hard seal can also be applied to pneumatic soft seal butterfly valve under medium and high pressure conditions.

4. Sealing performance: soft sealing and triple eccentric hard seal butterfly valve have good sealing performance, and triple eccentric butterfly valve can maintain good sealing in the environment of high pressure and high slip temperature.

2. What is the scope of application of the hard seal butterfly valve?

The hard seal butterfly valve, also known as the flap valve, is a simple control valve, which can also be used for the on/off control of low-pressure pipeline media. The hard-sealed butterfly valve mainly plays the role of shut-off and throttling on the pipeline. The butterfly valve opening and closing part is a disc-shaped butterfly plate, which rotates around its own axis in the valve body, so as to achieve the purpose of opening and closing or adjusting, so what is the scope of application of the hard seal butterfly valve?

The hard seal butterfly valve is suitable for the pipelines that transport various corrosive and non-corrosive fluid media in the furnace, gas, steam, natural gas, city gas, hot and cold air, chemical smelting engineering and power generation environmental protection systems, and is used to regulate and cut off the flow of the medium. The flammable hard seal butterfly valve is divided into manual hard seal butterfly valve, pneumatic hard seal butterfly valve, and electric hard seal butterfly valve.

The structural differences between soft seal butterfly valve and hard seal butterfly valve are mainly as follows:

1. Structural differences: soft seal butterfly valves are mostly midline type hard seals, and most of them are single eccentric, double eccentric, and triple eccentric butterfly valves.

2. Temperature resistance: soft seal is used in room temperature environment. Hard seals can be used in low temperature, normal temperature, high temperature and other environments.

3. Pressure: soft seal low pressure-normal pressure, hard seal can also be used in medium and high pressure and other working conditions.

4. Sealing performance: soft seal and triple eccentric hard seal butterfly valve have good sealing performance, and triple eccentric butterfly valve can maintain good sealing in high pressure and high temperature environment.

In view of the above characteristics, the soft seal butterfly valve is suitable for two-way opening and closing and adjustment of ventilation and dust removal pipelines, water treatment, light industry, petroleum, chemical and other industries. Hard seal butterfly valves are mostly used in heating, gas supply, gas, oil, acid and alkali environments.

With the widespread use of butterfly valves, its characteristics of easy installation, convenient maintenance and simple structure are becoming more and more obvious. Electric soft seal butterfly valves, pneumatic soft seal butterfly valves, hard seal butterfly valves, etc. have begun to replace electric gate valves and globe valves on more and more occasions. Providence of Fande Valve Technology Shanghai.

We will describe in detail their definitions, characteristics, advantages and disadvantages according to this selection.

A hard seal butterfly valve is a seal that is made of metal or other hard materials on both sides of the sealing pair"Hard sealed"。The sealing performance of the butterfly valve hard seal is poor, but it is resistant to high temperature, high pressure, wear and tear, and has good mechanical properties. For example, the commonly used Vton hard-sealed butterfly valve can be used in high-temperature occasions with a temperature of 650.

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 alloy).

Soft Seal Butterfly Valve: One side of the sealing pair is made of metallic material, and the other side is an elastic non-metallic material, generally rubber and PTFE, which is called"Soft seal".The sealing performance of this seal is better, such as the commonly used Weidun VTON's imported soft seal butterfly valve, no matter used in water, oil, gas and other media, it can achieve zero leakage and good sealing; However, it is not resistant to high temperature, easy to wear, and has poor mechanical properties.

Such as: steel + rubber; steel + PTFE;

The soft sealing seat is made of non-metallic materials with certain strength, hardness and temperature resistance, with good sealing performance, and the hard seal of Weidun VTON can reach zero leakage, but the life and adaptability to temperature are relatively poor. Hard seals are made of metal, and the sealing performance is relatively poor, although some valve manufacturers claim to be able to achieve zero leakage butterfly valves, but in reality it is difficult to achieve. Soft sealing can not meet the process requirements of some corrosive materials, and hard seal disc valve can solve it!

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 the soft seal disc valve is that it has good sealing performance, and the disadvantage is that it is easy to age, wear and tear, and has a short service life. Hard-seated butterfly valves have a long service life, but the tightness is relatively worse than that of soft-sealed butterfly valves.

The difference between the structure of a hard-seated butterfly valve and a soft-seated butterfly valve:

1. Structural differences: soft seal butterfly valves are mostly midline butterfly valves, and hard seals are mostly single eccentric butterfly valves, double eccentric butterfly valves, and triple eccentric butterfly valves.

2. Temperature resistance: soft seal butterfly valve is used in room temperature environment. Hard seals can be used in low temperature, normal temperature, high temperature and other environments.

3. Pressure: soft seal butterfly valve low pressure-normal pressure, hard seal can also be used under medium and high pressure conditions.

4. Sealing performance: soft seal butterfly valve and triple eccentric hard seal butterfly valve have good sealing performance, and triple eccentric butterfly valve can maintain good sealing in high pressure and high temperature environment.

Selection of soft seal butterfly valve and hard seal butterfly valve.

In view of the above characteristics, VTON soft seal butterfly valve is suitable for two-way opening and closing and adjustment of ventilation and dust removal pipelines with high sealing requirements and low temperature and pressure, water treatment, light industry, petroleum, chemical and other industries. Weidun VTON hard seal butterfly valve is mostly used in the occasion of relatively low sealing requirements, but the medium temperature is high, the pressure is high, and the wear is relatively strong, heating, gas supply, and gas, oil, acid and alkali and other environments.

Features of Soft Seal Butterfly Valve Small, lightweight, easy to disassemble and maintain, and can be installed in any position. The structure is simple, compact and 90 degrees open and close quickly. The operating torque is small, labor-saving and lightweight. The flow characteristics tend to be straight, and the regulation performance is good. The number of opening and closing tests is more than 10,000 times, and the service life is long. , to achieve complete sealing, gas test leakage is zero. , choose from different component materials, and can be suitable for a variety of media. Features of Hard Seal Butterfly Valve:

1) The unique design of three-way eccentricity [1] enables frictionless transmission between the sealing surfaces, which prolongs the service life of the valve.

2) Elastic seal is generated by torque.

3) The ingenious wedge-shaped design makes the valve have the function of automatic sealing that is tighter and tighter, and the sealing surface has compensation and zero leakage.

4) Small size, light weight, light operation and easy installation.

5) Pneumatic and electric devices can be configured according to user requirements to meet the needs of remote control and program control.

6) The material of the replacement parts can be applied to various media, and the lining can be anti-corrosion.

7) Diversification of continuous structure: butt clamp, flange, butt welding.

According to the economic conditions and the medium used and the on-site environmental conditions, the customer can choose whether the butterfly valve is soft or hard sealed.

Hard seal butterfly valve: The seal pair is made of metal material or other hard materials on both sides is called a hard seal. 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 alloy).

Soft seal butterfly valve: The two sides of the sealing pair are made of metal material on one side and the other side is elastic non-metallic material is called 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]; and other rotary lobe pumps.

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

Hard-seated butterfly valves have a long service life, but the tightness is relatively worse than that of soft-sealed.