Ashcroft Threaded Diaphragm Seals

  • Broad selection of materials for meeting various service applications, including Teflon, Viton and Kalrez diaphragms.
  • Elastomeric diaphragm is clamped securely between the top and bottom housings by clamp rings, assuring positive seal.
  • Top housing is contoured to match diaphragm, minimizing distortion of the diaphragm should the pressure instrument be removed.
  • Continuous duty.
  • Fill/bleed connection is standard.
  • Top housing and diaphragm are nonremovable.
  • Teflon, Viton and Kalrez diaphragms available in threaded and flanged inlet connection

Model Index for Diaphragm Seals

Type 101

Ashcroft Type 101 Capsule Diaphragm Seals

Threaded with Flushing Connection The diaphragm seal connects directly to the process by means of a female NPT thread

Type 101

Ashcroft Type 101 Capsule Diaphragm Seals

Threaded with Flushing Connection The diaphragm seal connects directly to the process by means of a female NPT thread

Type 200

200-201 Threaded Diaphragm Seals

Bonded Viton, Kalrez and Teflon
The diaphragm is bonded permanently to the top housing and is the removable type

Type 201

200-201 Threaded Diaphragm Seals

Threaded with Flushing Connection The diaphragm seal connects directly to the process by means of a female NPT thread

Type 300

300-301 Threaded Diaphragm Seals

Bonded Viton, Kalrez and Teflon

The diaphragm is bonded permanently to the top housing and is the removable type

Type 301

300-301 Threaded Diaphragm Seals

Threaded with Flushing Connection

The diaphragm seal connects directly to the process by means of a female NPT thread

Type 400, 401

Type 400, 401 Diaphragm Seal Welded 1" Male NPT

Diaphragm Seal Welded

1" Male NPT 

Type 310, 315

310-315-diaphragm seals

All Welded Mini Seal

Male-Female threaded 

Type 311

311 threaded midi diaphragm seal

Midi-Diaphragm Seal

Female and Male Threaded

Type 312

312 Midi-Diaphragm Seal Female NPT with Flushing Connection

Midi-Diaphragm Seal

Female NPT with Flushing Connection

Type 500, 501

500-501 All-Welded Diaphragm Seals

Diaphragm Seal Welded



Type 510, 511

510-511 All-Welded Diaphragm Seals

Diaphragm Seal Welded

Type 740, 741

740-741 High-Displacement Diaphragm Seals

High Displacement Welded Seal