To summarize the features of knife gate valves:

Release time:

2022-03-28

Knife Gate Valves: These include plate-type gate valves, knife-type slurry gate valves, knife-type slag-discharge gate valves, single-clamp slurry gate valves, and manual single-clamp knife gate valves. According to the configuration of their sealing surfaces, gate valves can be classified into wedge-type gate valves and parallel-type gate valves. Wedge-type gate valves, in turn, can be further divided into single-gate, double-gate, and flexible-gate types.

　　Knife Gate Valves: These include plate-type gate valves, knife-type slurry gate valves, knife-type slag-discharge gate valves, single-clamp slurry gate valves, and manual single-clamp knife gate valves. According to the configuration of their sealing surfaces, gate valves can be classified into wedge-type gate valves and parallel-type gate valves. Wedge-type gate valves, in turn, can be further subdivided into single-gate, double-gate, and flexible-gate types.

　　Parallel-gate valves can be classified into single-gate and double-gate types. According to the thread orientation of the valve stem, they can be further divided into rising-stem gate valves and non-rising-stem gate valves. Structural features: This valve boasts distinct advantages such as lightweight operation, reliable sealing, excellent elastic memory, and a long service life. It can be widely used in pipelines for tap water, sewage, construction, petroleum, chemical industry, food, pharmaceuticals, light and textile industries, power generation, shipbuilding, metallurgy, energy systems, and other applications as both a regulating and shut-off device.

　　Features of knife gate valves: Ultra-short structural length saves materials and significantly reduces the overall weight of the piping system. They occupy a small footprint, effectively support pipe strength, and help minimize the likelihood of pipeline vibration. The gate plate is made of austenitic stainless steel, greatly enhancing its corrosion resistance and effectively preventing sealing leaks caused by gate plate corrosion.

　　The upper sealing packing is made of flexible PTFE, ensuring reliable sealing and simple, responsive operation. The gate plate functions like a knife blade, effectively blocking various impurities in the medium. If a hard-sealed stainless steel material is used and the valve disc is subjected to spray welding treatment, the valve’s requirements for temperature and pressure can be significantly enhanced.

The vast majority of stainless steel knife gate valves employ forced sealing: that is, when the valve is closed, an external force is applied to forcibly press the gate against the high-pressure valve seat, thereby ensuring a tight seal on the sealing surfaces. Some gates can also be designed to undergo slight deformation, which helps improve their manufacturability and compensate for any misalignment in the sealing surface angles that may occur during the manufacturing process. Such gates are referred to as flexible gates. The majority of knife gate valves rely on forced sealing—meaning that when the valve is closed, an external force is used to press the gate firmly against the high-pressure valve seat, thus guaranteeing a secure seal on the sealing surfaces. Valves of this type are generally installed horizontally in pipelines.

2023-05-11

Next, let’s talk about several operating procedures for knife gate valves.

When a gate valve is closed, the sealing surfaces rely solely on the pressure of the medium to achieve a seal—specifically, the sealing surface of the gate is pressed against the valve seat on the opposite side by the medium’s pressure, thereby ensuring a tight seal. This type of sealing is known as self-sealing. In contrast, most gate valves employ forced sealing: when the valve is closed, an external force must be applied to press the gate against the valve seat in order to guarantee the sealing performance of the sealing surfaces. Such valves should be installed vertically in the pipeline.

2023-05-11

Next, let’s talk about whether knife gate valves have fire-resistant and anti-static requirements.

When an electrostatic knife gate valve is opened or closed, the sphere and the valve seat experience mutual friction. The static electricity generated by this friction tends to accumulate on the sphere—something that is unacceptable for ball valves used in gas, fuel, and chemical pipelines, as it could potentially lead to pipeline explosions. Ball valves with antistatic designs are equipped with static discharge devices.

2023-05-11

Next, let’s talk about some important considerations for the installation, operation, and maintenance of pneumatic knife gate valves.

Pneumatic knife gate valves have a wide range of applications, spanning from ordinary fields to more diverse industries—from coal preparation, gangue removal, and slag discharge in coal-fired power plants to urban wastewater treatment; from general industrial pipelines to pipeline systems used in food, sanitation, and pharmaceutical industries. So, what are the key considerations when installing, using, and maintaining pneumatic knife gate valves?

2023-05-11

Slurry Valve Manufacturer: How are stainless steel knife gate valves good?