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311/312 All-Welded Midi-Diaphragm Seal

Brand: Ashcroft Inc

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The Ashcroft 311 and 312 midi-diaphragm seals or isolation devices are used in confined areas to protect measuring instruments.

Used to ensure process compatibility, they are also applied when process media exhibits high temperature and pulsation.

This model is ideal with limited space installations.
Features
  • All-welded metal construction, prevents leakage of process media 
  • No gaskets or bolts 
  • For use on pressure gauges up to 3-1/2" from vacuum to 1,000 psi and 4-1/2" gauges 30 to 1,000 psi 
  • Top housing material 316L stainless steel standard 
  • Diaphragm materials in 316L stainless steel, Hastelloy® C and tantalum 
  • Bottom housing materials in 316L stainless steel and Hastelloy® C 
  • 1/4" NPT or 1/2" NPT instrument connections 
  • Type 312 furnished with 1/8" NPT flushing connection 
  • Type 312 not available in male process connections
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The Ashcroft 311 and 312 midi-diaphragm seals or isolation devices are used in confined areas to protect measuring instruments.

Used to ensure process compatibility, they are also applied when process media exhibits high temperature and pulsation.

This model is ideal with limited space installations.
Features
  • All-welded metal construction, prevents leakage of process media 
  • No gaskets or bolts 
  • For use on pressure gauges up to 3-1/2" from vacuum to 1,000 psi and 4-1/2" gauges 30 to 1,000 psi 
  • Top housing material 316L stainless steel standard 
  • Diaphragm materials in 316L stainless steel, Hastelloy® C and tantalum 
  • Bottom housing materials in 316L stainless steel and Hastelloy® C 
  • 1/4" NPT or 1/2" NPT instrument connections 
  • Type 312 furnished with 1/8" NPT flushing connection 
  • Type 312 not available in male process connections
1 model matching criteria
  • Process Connection - 1/4" Male NPT
  • Type - All-Welded Midi-Seal
  • Diaphragm Material - 316L Stainless Steel
  • Housing Material - Bottom: 316L Stainless Steel, Top: 316L Stainless Steel
  • Instrument Connection Size - 1/4" Female NPT
  • Filling Fluid - Glycerin
Out of Stock

Specifications

Fill Material

  • Glycerin
  • Halocarbon
  • Silicone
  • Syltherm

Approvals & Certifications

  • CRN
  • GOST

NPT Connection

  • 1” NPT Female
  • 1” NPT Male
  • 1/2” NPT Female
  • 1/2” NPT Male
  • 1/4” NPT Female
  • 1/4” NPT Male
  • 3/4” NPT Female
  • 3/4” NPT Male

Temperature Range

  • -21° to 398.9° C (-70° to 750° F)

Enclosure, Body Material

  • 316L Stainless Steel
  • Hastelloy C-276

Pressure Range

  • 4-1/2” Gauge psi: 30 to 1,000 (kPa: 206.8 to 6,895, bar: 2 to 68.95)
  • Up to 3-1/2”: Vacuum to psi: 1,000 (kPa: 6,894, bar: 69)

Diaphragm Material

  • 316L Stainless Steel
  • Hastelloy C-276
  • Tantalum

NACE & NIST

  • NACE

Typical Applications

  • Biogas & Biodiesel
  • Chemical & Petrochemical
  • Oil & Gas Applications
  • Oil & Gas Fracking
  • Refineries
  • Water & Wastewater