H74W Single Disc Thin Wafer Check Valve

1. Basic Definition
The H74 wafer check valve (also known as a wafer-type check valve) is a valve that achieves unidirectional flow through a seal between the disc and seat. It is typically used to prevent backflow of media within pipelines. Its model number "H71" complies with the national standard (GB/T 12236), indicating a wafer-type, flange-connected check valve.

2. Structural Features
Valve body materials: Common carbon steel, stainless steel (304/316), alloy steel, etc., suitable for various operating conditions (such as corrosive media or high-temperature and high-pressure environments).
Seal Design: The disc and seat utilize elastic or metal seals. Some models include a buffer device to reduce water hammer.
Mounting Method: Secured by flange or bolts, the structure is compact and takes up little space.

3. Applications
Industrial pipelines: Applications requiring unidirectional flow in the petroleum, chemical, water treatment, HVAC systems, and other applications.
Pump outlet protection: Prevents backflow of media during pump shutdown, potentially damaging equipment (such as pumps and compressors). Special Media: Suitable for media such as steam, oil, acids and alkalis. Select the appropriate model based on the material.

4. Selection Key Points
Media Parameters: Clearly identify the media type, temperature, pressure, and flow range.
Connection Dimensions: Match the pipe flange standard (such as the PN/Class series).
Sealing Requirements: For high-tightness applications, metal seals are preferred. For corrosive media, corrosion-resistant materials (such as fluorine-lined discs) are preferred.

5. Maintenance and Precautions
Regular Inspection: Clean the disc to remove foreign matter and inspect the seal for wear.
Installation Specifications: Ensure that the media flow direction is aligned with the direction indicated by the valve arrow to avoid reverse installation.
In the event of extended non-use: Drain the internal media to prevent rust or crystallization.