402-403 Flanged All-Weld Diaphragm Seals

The Ashcroft® 402 and 403 flanged all-weld diaphragm seals or isolation devices protect pressure measuring instruments. Used to ensure process compatibility, they are also applied when process media exhibits high temperature, pulsation or the potential to clog an instrument connection. An ideal selection for applications needing added product integrity.

Key Features:
  • Wide selection of diaphragm and lower housing materials
  • All welded construction
  • Flushing port (type 403) provides easy cleaning / flushing due to process media prone to clogging
Specifications:
  • Style:
    Type 402: flange
    Type 403: flange with flushing port
  • Process size: 1/2″ to 3″
  • Flange rating: 150 to 1500 class

The 402 and 403 flanged all-weld diaphragm seals are ideal where fugitive emission and hazardous process protection are essential:

Process Market:
  • Oil and Gas
  • Refineries
  • Chemical and Petrochemical
  • Water and Wastewater
Process Applications:
  • Oil and Gas Fracking
  • NACE Compliant Processes (Sour Gas Separation)
  • Biogas and Biodiesel
 

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Tools

  • Distributor Locator

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  • Materials Selector

    Use the selector to review compatible wetted materials and requirements of your application.
  • Unit Convertor

    Need to convert measurement units? Check out our quick and easy approach to pressure, temperature and flow unit conversions.

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