Non-Replaceable

Home » Products » Diaphragm Seals » Non-Replaceable » Type 25/25H Standard & Elevated Pressure, Non-Replaceable Diaphragm Seals

Type 25/25H Standard & Elevated Pressure, Non-Replaceable Diaphragm Seals

REQUEST A QUOTE VIEW BY PART NUMBER
Download Literature
Water/
Wastewater
  • Designed to isolate the pressure measuring instrument from corrosive or viscous process media
  • Utilize an all welded, all metallic housing design to eliminate potential leak paths
  • For use with gauges with dial sizes of 2-1/2" and smaller, and pressure ranges no less than 100 psig
  • Housing and diaphragm offered in a variety of materials to suit most applications
  • A flushing port is available to clean wetted areas and prevent process media build up
  • Consider instrument size, pressure range, media composition, ambient and operating temperature, and maximum working pressure when selecting
  • Capillaries and cooling elements are available for elevated process temperatures, see options & accessories below
  • Fill fluid must be compatible with process media; i.e. Glycerin may become volatile in conjunction with a strong oxidizing agent such as chlorine, forms of  oxygen or peroxide and nitric acids

If you are viewing on a smaller screen or with screen zoom, please use the horizontal scroll bar at the bottom of this table to see all information.

TYPES 25 (2,500 psi) 25H (5,000 psi)    
INSTRUMENT CONNECTION SIZES 02 1/4" NPT 04 1/2" NPT    
UPPER HOUSING MATERIALS M Monel 400 P Carpenter 20 S 316 Stainless steel
DIAPHRAGM MATERIALS H Hastelloy C-276 P Carpenter 20 *    
M Monel 400 * S 316 Stainless steel    
PROCESS CONNECTION SIZES 02 1/4" NPT 04 1/2" NPT    
LOWER HOUSING MATERIALS H Hastelloy C-276 P Carpenter 20    
M Monel 400 S 316 Stainless steel    
FLUSHING CONNECTIONS 1F 1/8" NPT 2F 1/4" NPT    

* When selecting a Monel or Carpenter 20 Diaphragm, the upper and lower housing must be the same material.

If you are viewing on a smaller screen or with screen zoom, please use the horizontal scroll bar at the bottom of this table to see all information.

PRODUCT SPECIFICATIONS
Seal type Threaded with welded diaphragm
Instruments Type Size Minimum Pressure Maximum Pressure
Gauges 2-1/2" 0 psig to 100 psig 0 psig to 2,500 psig (25H - 5,000 psig)
Transducers — 0 psig to 60 psig 0 psig to 2,500 psig (25H - 5,000 psig)
Switches — 0 psig to 60 psig 0 psig to 2,500 psig (25H - 5,000 psig)
Upper housing Type Non-continuous duty
Connections 1/4" NPT, 1/2" NPT
Materials 316 Stainless Steel
Diaphragm Size 1.28"
Displacement 400 mm3
Materials 316 Stainless Steel (Exotic materials available on request)
Lower housing Connections 1/4" NPT, 1/2" NPT, 3/4" NPT, 1" NPT, 1-1/4" NPT, 1-1/2" NPT
Materials 316 Stainless Steel (Exotic materials available on request)
Flushing port Optional 1/8" NPT and 1/4" NPT
Operating temperature   Operating temperature is determined by the temperature/pressure
configuration. See Material Temperature table.
Applications Dimensions Download Data Sheet Fill Fluid Temperature Table Frequently Asked Questions Reference Information Thermal Error Calculations Warranty Information

Options & Accessories

Cooling Elements

  • 1/4" NPT X 1/4" NPT Cooling Element (1/4" NPT X 1/4" NPT-CE)
  • 1/2" NPT X 1/2" NPT Cooling Element (1/2" NPT X 1/2" NPT-CE)
  • Works in combination with diaphragm seal to isolate instrument from high media temperatures
  • Recommended for process temperatures above 212 °F
  • Requires direct mounted system
  • Effective temperature reductions of 200 °F depending upon ambient conditions
  • High >212 °F process temperature, low < -40 °F process temperature
  • All Stainless Steel construction

WARNING: This product can expose you to chemicals including Nickel, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov

Diaphragm Seal Fill Options

  • Glycerin (GY) *
  • Silicone (SL)
  • Halocarbon® (HL)
  • Neobee M20 (NB)
  • Mineral Oil (MO)
  • Propylene Glycol (PG)

* Not recommended for use in vacuum applications.

Distribution Manifolds

NOSHOK's Distribution Manifolds connect multiple instruments to one diaphragm seal, eliminating multiple connections that lead to possible leak paths.

View NOSHOK Distribution Manifolds

Plain & Armored Capillaries

  • 5 ft. SS Armored Flexible Capillary, 1/4" NPT (AC-02-02-5) per ft. adder (AC-02-02-#)
  • 5 ft. SS Armored Flexible Capillary, 1/2" NPT (AC-04-04-5) per ft. adder (AC-04-04-#)
  • Stainless Steel capillaries available with or without Stainless Steel armor
  • Protects the instrument from high or low process temperatures
  • Allows remote mounting of pressure instrument(s)
  • Select the shortest capillary length possible, as changes in ambient temperature conditions may significantly affect the accuracy and response time of the instrument
  • Standard length 5', others available
  • Installation on analog gauges requires a gauge support and gauge adaptor, or other surface mounting provisions
  • Any level difference between the instrument and the seal will result in a pressure indication error; make sure to compensate for the level difference during calibration of the diaphragm seal assembly if the level difference is known
  • Filling options for capillaries
    • Silicone - specify to 10 or 20 feet (SL-C)
    • Halocarbon® - specify to 10 or 20 feet (HL-C)

WARNING: This product can expose you to chemicals including Lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov

WARNING: This product can expose you to chemicals including Nickel, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov

WARNING:This product can expose you to chemicals including Nickel, which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov

Application Insights Articles
Application Of Diaphragm Seals (Chemical Seals) To Aggressive Media
Application Of Diaphragm Seals (Chemical Seals) To Aggressive Media
Custom Measurement Solutions for Tire Presses
Custom Measurement Solutions for Tire Presses
Critical Factors Before Selecting Pressure & Temperature Measurement Instrumentation
Critical Factors Before Selecting Pressure & Temperature Measurement Instrumentation

PT Transmitter Crossover Tool

Convert to PT Series