Farris Relief Valve Sizing Software
PRESSURE RELIEF VALVE ENGINEERING HANDBOOK CHAPTER 2 - TERMINOLOGY Safety Valve A pressure relief valve characterized by rapid opening or closing and normally used to relieve compressible fluids. Relief Valve A pressure relief valve characterized by gradual opening or closing generally proportional to the increase or decrease in pressure.
- Designed for lower capacity systems and tighter spaces
- Available in a B orifice from 500 to 6,000 PSI
- Available in threaded inlet sizes from 3/4” through 2”
- Available in orifice sizes “E” and “G”
- Available in threaded inlet sizes from 1/2″ through 3″
- Available in orifice sizes “C” through “K”
- Available in flanged inlet sizes from 1/2” through 4”
- Available in orifice sizes “C” through “M”

- Available in orifice sizes “C” and “D”
- Pressure ranges from 3000psi to 8700psi
- Available in flanged inlet sizes from 1″ through 8″
- Available in orifice sizes “D” through “T” and Full Bores 1 1/2″ to 8″
- Weather Caps: 1/2″ to 24″
- Bleed Rings: 1″-6″, Flange Rating 150# RF – 600# RF, 1/2″ NPT Tap
- Rebuilt Relief and Line Valves
- Rebuilt Kimray Products
- Rebuilt Western and Texsteam Pumps

General Information provides general information on pressure relief valves and Mercer’s story.
Product Line gives a quick overview of our entire product line.
Farris Relief Valve Sizing Software Download
Do the sizing yourself
Use our Excel spreadsheet sizing spreadsheet to help choose the right valve for the job.
Or let us do the sizing for you!
Farris Relief Valve Sizing Program
Use the following forms to provide us with the specifics of your application and we’ll take it from there. Just save the filled out form on your computer and then email it to insidesalesgroup@mercervalve.net.
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