Knife type gate valve is suitable for standard speed reading

Pneumatic knife typeflangegate valve

Knife type gate valveDue to its low opening and closing force and good cutting effect, it is widely used in working conditions containing solid particles or fiber media such as metallurgy, mining, papermaking, and sewage treatment. It is crucial to follow authoritative standards to ensure the long-term stable operation of products in complex environments. The following content provides a quick reference for enterprise selection, design, and procurement.

1、 Core industry standard: JB/T 8691-2013 "Non valve cover knife gate valve"

Applicable scope: nominal pressure of 0.25 MPa, 0.6 MPa, 1.0 MPa, nominal size of DN50-DN900, applicable temperature of 0 ℃ -200 ℃.

● Key terms

• Specify the minimum wall thickness and material grade for major components such as valve bodies and gate plates;

• Clearly state that the shell test pressure is 1.5 times the rated pressure and the sealing test pressure is 1.1 times;

• Supplement the minimum inner diameter of the valve body channel and the length requirements for the clamp type connection structure;

The international advanced practices of MSS SP-81-2006 were cited and expanded based on domestic working conditions. ([bzxz.net][1])

This standard is currently a highly recognized specialized specification for knife type gate valves in the industry, covering design, manufacturing, inspection, and ordering instructions.

2、 National universal standards that must be followed synchronously

These two national standards provide unified testing methods and material baselines for various types of metal valves. Knife gate valves must comply with their general terms while implementing JB/T 8691.

3、 Selection and Acceptance Points

1. Verification and certification: The supplier shall provide both JB/T 8691 type test report and GB/T 13927 pressure test certificate.

2. Pay attention to the sealing pair: For slurry and high solid content working conditions, it is recommended to use hard face seals or PTFE soft seals and ensure that they are replaceable.

3. Material matching: Stainless steel such as CF8M and 2205 are preferred for corrosive media; WCB can be selected for room temperature clean water.

4. Spare parts and maintenance: Standardized valve stem, packing, and driving device are used for easy and rapid maintenance in the later stage.

Conclusion

Strictly implementing JB/T 8691-2013, supplemented by the general requirements of GB/T 13927 and GB/T 12224, is the foundation for ensuring the safety, reliability, and high service life of knife gate valves. Our company always organizes design, procurement, and inspection according to the above standards, and is committed to providing users with reliable fluid control solutions.