Diaphragm Seals

42MW Series

Hyett Diaphragm Seals offer superior construction features for total dependability, including top quality steel and other materials, precision machining of threaded connections.


  • Diaphragm Seals - 42MW

    Welded diaphragm seal

  • Diaphragm Seals - 42MW01

    Welded diaphragm seal with 1/4"NPT cleaning port

  • Diaphragm Seals - 42HPW

    Welded diaphragm high pressure seal

  • Diaphragm Seals - 42HPW01

    Welded diaphragm high pressure seal with 1/4" cleaning port.


Model 42 MW are clamped metal design diaphragm seals.  They feature an interlocking male-female housing construction inside of the bolt circle for proper alignment.  Welded diaphragm seals are designed to give a continuous filled system.  They allow removal of the upper housing with instrument from the lower housing without losing fill.  These seals are available in threaded models for pressure to 2500 PSI, and flange attached (42FW) for 150#, 300# or 600# ratings.  All welded seals include a standard fill/bled port in the top housing.  Standard lower housing and diaphragm construction is 316 stainless steel.


  • Cleaning port: With (42MW01) or without (42MW)
  • Maximum pressure 2500 psi or 5000 psi (42HPW)
  • Sizes: 1/4" – 1" NPT or flanged available in 150#, 300# or 600# (42FW series)
  • Filling Liquids: Silicone, High Temperature Silicone, Glycerin,
  • Lower Housing Materials: Optional Steel, 304 Stainless Steel, 316 Stainless Steel, Hastelloy B or C, Monel, Nickel, PVC, Teflon, Brass, Titanium and Polypropylene
  • Diaphragm Materials: Standard 316 stainless steel;
    Specialty materials include 304 stainless steel, Monel, Tantalum, Hastelloy B&C, Carpenter 20, Nickel, Titanium and Teflon
  • Options: 316SS upper housing with stainless steel rings, nuts and bolts. Pipe caps for flushing fittings. Flange faces – raised face, flat face or ring seal



Additional information


42HPW, 42HPW01, 42MW, 42MW01

You may also like…