Construction classification

1) Parallel gate valve: a gate valve with a sealing surface parallel to the vertical centerline, that is, two sealing surfaces parallel to each other. Parallel gate valves typically use a double gate structure In parallel gate valves, the structure with thrust wedges is the most common, with double-sided thrust wedges in the middle of the two gate plates. This type of gate valve is suitable for low-pressure small and medium-sized (DN40-300mm) gate valves. There are also those with springs between the two rams, which can generate pre tightening force and facilitate the sealing of the rams Wedge gate valve: A gate valve with a sealing surface at an angle to the vertical centerline, i.e. two sealing surfaces forming a wedge shape

1. According to the structure of the gate, it can be divided into

1) Parallel gate valve: a gate valve with a sealing surface parallel to the vertical centerline, that is, two sealing surfaces parallel to each other. Parallel gate valves typically use a double gate structure In parallel gate valves, the structure with thrust wedges is the most common, with double-sided thrust wedges in the middle of the two gate plates. This type of gate valve is suitable for low-pressure small and medium-sized (DN40-300mm) gate valves. There are also those with springs between the two rams, which can generate pre tightening force and facilitate the sealing of the rams Wedge gate valve: A gate valve with a sealing surface at an angle to the vertical centerline, i.e. two sealing surfaces forming a wedge shape The inclination angle of the sealing surface generally includes 2 ° 52 ′, 3 ° 30 ′, 5 °, 8 °, 10 °, etc. The size of the angle mainly depends on the temperature of the medium. The higher the working temperature, the larger the angle taken to reduce the possibility of wedging during temperature changes In wedge gate valves, there are three types: single gate, double gate, and elastic gate. The single gate wedge type gate valve has a simple structure and reliable use, but it requires high precision in the sealing surface angle, making it difficult to process and repair. It is prone to clamping and scratching, and there is a high possibility of wedging during temperature changes. The structure of the double gate wedge gate valve is relatively complex and is commonly used in water and steam medium pipelines. Its advantages are that it has low precision requirements for the angle of the sealing surface, temperature changes are not easy to cause wedging, and when the sealing surface is worn, gaskets can be added to compensate. However, this type of structural component has many parts that are prone to bonding in viscous media, affecting sealing. The main issue is that the upper and lower baffles are prone to rusting after long-term use, and the gate is prone to detachment. The structural feature of the elastic wedge gate valve is that there is a circular groove around the gate, which provides appropriate elasticity for the gate. It has the advantages of simple structure and reliable use of a single gate wedge gate valve, as well as the ability to generate a small amount of elastic deformation to compensate for the deviation generated during the sealing surface angle processing, improving the process performance, and has been widely adopted Special purpose gate valves, such as large-diameter gate valves used on long-distance oil and gas pipelines, adopt a single gate structure for cleaning valves and pipelines