Manufacturing standards for slurry valves require...

Release time:

2022-01-27

The manufacturing standards for slurry valves are as follows: 1. With the exception of the valve disc and packing gland, which are made of 316L stainless steel, the remaining valve body, valve stem, handwheel, and support rods shall be made of cast steel or wear-resistant cast iron.

The manufacturing standards for slurry valves are as follows:

1. With the exception of the valve disc and packing gland, which are made of 316L stainless steel, the remaining valve body, valve stem, handwheel, and support rods are all made of cast steel or wear-resistant cast iron.

2. The U-shaped seal of the slurry valve is made of fluororubber, and the lateral sealing packing uses PTFE packing.

3. The thickness of the valve body and valve disc shall comply with domestic standards. Of course, the thicker the valve disc, the better the performance.

4. A closing limiter shall be installed on the valve to prevent leakage or damage to the U-shaped seal caused by over-closing of the valve, while ensuring the valve remains sealed.

5. The handle features a double-bearing structure and is equipped with an oiling point (hole), ensuring smooth, flexible valve operation and convenient use.

6. The soda ash plant is equipped with specialized instruments to inspect the material and defects of slurry valves; all products that fail to meet quality requirements will be returned as required.

Slurry valves are generally categorized into two types: integral and clamp-type. The valve bodies of slurry valves are often made from materials that meet specific requirements, and their structures are either U-shaped or T-shaped. The valve body of an integral slurry valve features an O-ring sealing structure, which differs from the disc-type slurry valve's design. This structural design overcomes the drawback of the U-shaped sealing structure in disc-type slurry valves, which tends to shift and deform under external forces. The gate plates of both types of slurry valves are roughly identical and adopt a knife-edge design, effectively addressing the issues of difficulty in closing the valve and leakage.

There are two methods for actuating slurry valves: one is manual, which is commonly used for valves with relatively low operating torque; the other is electro-hydraulic actuation, which provides high torque and allows for flexible adjustment. As for fluid media, the resistance offered by slurry valves can be considered comparable to that of smaller valves. Moreover, in the sealing of slurry valves, graphite is mostly employed as a packing material, ensuring highly reliable sealing performance.

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?