400-401 All-Welded Diaphragm Seals

The Ashcroft® 400 and 401 all-welded 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:
  • Select diaphragm and lower housing materials
  • All-welded construction
  • Carbon steel rings (standard); 300 stainless steel rings (optional)
  • Pressure rated up to 320 bar; optional high-pressure rings to
    600 bar (type 401: 345 bar )
  • Flush port (type 401) provides easy cleaning / flushing due to process
    media prone to clogging
Specifications:
  • Style:
    Type 400: threaded
    Type 401: threaded with flushing port
  • Process size:
    Type 400: 1/4″ to 1″ NPT female;  1/4″ to 3/4″ NPT male
    Type 401: 1/4″ to 1″ NPT female

The 400 and 401 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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The Ashcroft® 100 and 101 threaded diaphragm seals or isolation devices protect pressure measuring instruments.

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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