What is the difference between the German standard gate valve and the national standard gate valve

This article analyzes in detail the difference between the German standard gate valve and the national standard gate valve. If you think it will help you, please raise your hand and give the American Vodon valve a thumbs up.

If the gate valve is divided according to the standard, it can be divided into GB is the national standard, the American standard (ANSI), and the German standard (DIN); Generally, China's gate valve brands use GB is the national standard, the American gate valve brand, such as the American Vton, generally uses the American standard (ANSI), and the German brand gate valve, such as the German lit, generally uses the German standard (DIN); So what is the difference between these three standard gate valves, this article will conduct a detailed analysis.

1. The standard is different.

GB is the national standard, American standard (ANSI), German standard (DIN).

2. Differences in models.

The valve model of the national standard is named according to the pinyin letter of the valve category. Such as: safety valves: A butterfly valve, D diaphragm valves, g check valves, H globe valves, J throttle valves, l Blowdown valves, P ball valves, Q traps, S gate valves, Z and so on.

American standard valves generally add 150lb, 300 and other pressure unit values behind them; The model number of the German standard is generally added to the DIN.

3. Difference in pressure level.

There are no special specifications between American standard valves, German standard valves, and national standard valves, which are nothing more than the difference between production standards and pressure levels, and the material of the valve body and the material of the internal parts are easy to say, nothing more than cast iron, cast steel, stainless steel, etc. Taking the American standard as an example, the American standard pressure level is from 125LB to 2500LB (or 200PSI to 6000PSI), and the standard main API, ANSI, commonly known as API, ANSI valves are American standard valves; The pressure of German standard valves is usually PN10 to PN320, using DIN standard; If it is a flange connection valve, the corresponding flange standard should also be used. The world's main valve standards are also the American Standard Petroleum Association API Standard, the American National Standard ANSI, the German Standard DINs, the Japanese Standard JIS, the National Standard GB, the European Union Standard EN, and the British Standard BS.

4. Standard difference of flanges; For example, the imported American standard gate valve of Vton of the United States, the standard of the flange is 150LB and 300LB of ANSI; The imported cast steel gate valve of the national standard, the flange standard is the standard of GB, JB, HG.

2. The length of the structure is different; For example, the length of the imported German standard gate valve and the national standard gate valve of the American Weidun VTON is the same, but the American standard gate valve is different, and the length of the American standard gate valve is relatively short.

3. The inspection requirements are different.

American standard, German standard, national standard) valve standards and inspection requirements:

Chinese National Standard (GB).

Standard of the Ministry of Machinery of China (JB).

American National Standards (ANSI).

American Petroleum Institute Standards (API).

American Society for Testing and Materials (ASTM) standards

American Valve and Pipe Fitting Manufacturers Standardization Society Standard (MSS).

Japanese Industrial Standard (JIS).

German National Standard (DIN).

French National Standard (NF).

British National Standards, European Standards (BS, EN).

Other national valve standards (OCT, IEEE, UL).

The main difference between the German standard gate valve and the national standard gate valve is that the structural length is different, and the structural length of the German standard gate valve is slightly shorter than that of the national standard valve. Specifically, there is no special model specification between the German standard gate valve and the national standard gate valve, and the difference is that the production standard and pressure level are different. The pressure of German standard valves is usually PN10 to PN320, using DIN standard; If it is a flange connection valve, the corresponding flange standard should also be used.

The national standard valve is relatively according to the national standard standard. FYI.

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.

The opening and closing parts of the national standard gate valve are the ram, the direction of movement of the ram is perpendicular to the direction of the fluid, and the gate valve can only be fully opened and closed, and cannot be adjusted and throttled. Gate valve is a kind of valve with a wide range of use, the shut-off device with a general diameter of dn 50mm is selected from it, and sometimes the shut-off device with a very small diameter is also selected with two sealing surfaces of the gate valve gate, and the two sealing surfaces of the most commonly used mode gate valve form a wedge, and the wedge-shaped angle varies with the valve parameters, usually 50, and 2 ° 52 when the medium temperature is not high' 。The gate plate of the wedge gate valve can be made into a whole, which is called a rigid gate; It can also be made into a ram that can produce a slight amount of deformation to improve its manufacturability and make up for the deviation of the sealing surface angle in the processing process, which is called elastic ram.

Gate valve is the main control equipment for the flow or conveying volume of powder, grain, granular and small materials, and is widely used in metallurgy, mining, building materials, food, chemical and other industries to control flow changes or quickly cut off.

The national standard gate valve specifically refers to the type of cast steel gate valve, which can be divided into wedge gate valve and parallel gate valve according to the sealing surface configuration, and the wedge gate valve can be divided into: single gate type, double gate type and elastic gate type; Parallel ram type gate valves can be divided into single ram type and double ram type. According to the thread position of the stem, it can be divided into two types: open rod gate valve and dark rod gate valve.

When the national standard gate valve is closed, the sealing surface can only rely on the medium pressure to seal, that is, the sealing surface of the ram is pressed to the valve seat on the other side by relying on the medium pressure 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 forcibly pressed to the valve seat by external force to ensure the tightness of the sealing surface.

The gate plate of the national standard gate valve moves in a straight line with the valve stem, which is called the lifting rod gate valve (also known as the open rod gate valve). Usually there is a trapezoidal thread on the lifting rod, through the nut at the top of the valve and the guide groove on the valve body, the rotary motion is changed into linear motion, that is, the operating torque is changed into operating thrust.

When the valve is opened, when the ram lift height is equal to 1:1 times the valve diameter, the flow of the fluid is completely unobstructed, but this position cannot be monitored during operation. In actual use, it is marked by the apex of the valve stem, that is, the position that cannot be opened, as its fully open position.

In order to account for the lock-up phenomenon of temperature changes, it is usually rewound 1 2-1 turns back to the vertex position as the position of the fully open valve. Therefore, the fully open position of the valve is determined by the position of the ram (i.e. the stroke).

Some gate valves, the stem nut is located on the gate, and the handwheel rotates to drive the valve stem to rotate, and the gate is lifted, this kind of valve is called a rotary rod gate valve or a dark rod gate valve.

A gate valve is a valve in which the shut-off (ram) moves in the vertical direction along the centerline of the channel. The gate valve can only be used for full opening and full care in the pipeline, and cannot be used for adjustment and throttling. Gate valve is a kind of valve with a wide range of use, generally the diameter of DN 50mm shut-off device is used for it, sometimes the diameter of the shut-off device is also used gate valve.