Back To Top
Fisher™ MR98 Series Backpressure Regulators, Relief, and Differential Relief Valves
MR98 Series is used for backpressure or relief applications in liquid, gas, air, and steam service.
The Types MR98L, MR98H, and MR98HH are direct-operated and spring-loaded. The Types MR98LD, MR98HD, and MR98HHD use additional pressure loading to maintain relief differential pressures, backpressures or for remote setpoint adjustment.

CAD Drawings and Models: Click here
External Registration Animation: Click here
Internal Registration Animation: Click here

Fisher™ MR98 Series Backpressure Regulators, Relief, and Differential Relief Valves

Specs

Available Backpressure Constructions
MR98L: 2 to 38 psig / 0.14 to 2.6 bar set pressure range
MR98H: 15 to 200 psig / 1.0 to 13.8 bar set pressure range
MR98HH: 150 to 375 psig / 10.3 to 25.9 bar set pressure range
Available Pressure Differential Constructions
MR98LD: 2 to 38 psi / 0.14 to 2.6 bar set pressure range; max differential 150 psi / 10.3 bar
MR98HD: 15 to 200 psi / 1.0 to 13.8 bar set pressure range; max differential 300 psi / 20.7 bar
Available High Pressure Differential Constructions
MR98HDP: 15 to 200 psi / 1.0 to 13.8 bar set pressure range; max differential 600 psi / 41.4 bar
MR98HHD: 150 to 375 psi / 10.3 to 25.9 bar set pressure range; max differential 400 psi / 27.6 bar
Body and Spring Case Materials
Gray Cast Iron
WCC Steel
LCC Steel
Stainless Steel
Special Alloys: Monel®, Hastelloy® C, Aluminum-Bronze
Contact Sales Office for Special Alloys
Body Size and End Connection Styles
1/4-inch
1/2-inch / DN 15
3/4 and 1-inch / DN 20 and 25
1-1/2 and 2-inch / DN 40 and 50 (not available for Types MR95L and MR95LD)
End Connection Styles
NPT, SWE, and Welded and Integral CL150 RF, CL300 RF, CL600 RF, and PN 16/25/40 RF; all with 14-inch face-to-face (EN flanged-356 mm face-to-face)
Maximum Inlet Pressure
600 psig / 41.4 bar
Maximum Outlet Pressure
400 psig / 27.6 bar
Pressure Registration
Internal or External
MR98H Series Approximate Weights
1/4 NPT body: 5 lb / 2.3 kg
1/2-in / DN 15 body: 10 lb / 4.5 kg
3/4 and 1-in / DN 20 and 25 bodies: 22 lb / 10 kg
1-1/2 and 2-in bodies / DN 40 and 50: 55 lb / 25 kg
MR98L Series Approximate Weights
1/4 NPT body: 7 lb / 3.2 kg
1/2-in / DN 15 body: 15 lb / 6.8 kg
3/4 and 1-in / DN 20 and 25 bodies: 35 lb / 16 kg
Additional Technical Data
For additional technical information, contact your local Sales Office or refer to technical documentation.

Features

  • Versatility
  • Differential Pressure Capability
  • Special Service Capabilities
  • Large Turndown Ratio
  • Graphite Gaskets
  • Set Pressures to 400 psig / 27.6 bar
  • Tight Shutoff with Elastomer Seats
  • Easy Maintenance
  • Arctic and Cryogenic Temperature Constructions Options
  • FDA, USP Class VI, and ADI Free EPDM Wetted Elastomers

Education

Interesting in attending a training class?

Visit Course Listing!