Lip seal seat
Flexes under system pressure to press against the disk for a tighter seal.
Pilot operated
9500 Series
Pilot operated relief valves built on proven control design principles, featuring Auto Seat Technology. Snap pilots pop open at set pressure, while modulating pilots open gradually and put far less shock on your system.
- Set pressure
- 15 to 4,500 psig103 to 31,030 kPag
- Orifices
- D to T Plus 1½ to 8 in full bore
- Pilots
- Snap, modulating
- Code
- ASME XIIIUV stamped
Tap a point to look insideFive parts that make the 9500 work.
Overview
9500 Series at a glance
The 9500 uses a pilot that responds to pressure pickup at the inlet of the main valve. It is based on proven control design principles, features Mercer's Auto Seat Technology and is manufactured to the ASME Boiler and Pressure Vessel Code, Section XIII, for UV stamped applications.
Snap pilots pop the main valve open with an adjustable blowdown. Modulating pilots open the main valve gradually in response to system overpressure, putting far less shock on the system and giving strong resistance to wear and tear on main valve components.
Where it's used
- Regulating system pressures
- Air and gas service
- Liquid service (liquid modulating)
- Full bore requirements
How it works
Snap or modulating. See the difference.
A snap pilot pops the main valve fully open at set pressure. A modulating pilot opens it gradually as pressure rises above set, so the system sees far less shock.
Snap lift0%Closed
Modulating lift0%Closed
Snap: full lift at set, reseats after an adjustable blowdown. Modulating: opens in proportion to overpressure, closes as pressure falls.
Illustrative curves only. Actual lift characteristics depend on pilot type, size and setting.
Models at a glance
Compare the 9500 range
Ranges from Mercer's published figures. kPag conversions are rounded.
| Snap pilot | Gas modulating | Liquid modulating | |
|---|---|---|---|
| Service | Air and gas | Air and gas | Liquid |
| Orifices | D to T | D to T | F to T |
| Set pressure (psig) | 15 to 4,500 | 15 to 4,500 | 15 to 1,480 |
| Set pressure (kPag) | 103 to 31,026 | 103 to 31,026 | 103 to 10,204 |
Orifice sizes
Pick an orifice to compare sizes
Circles are drawn to scale by Mercer's actual orifice area. Switch model to see its range.
J
1.431 in²923 mm² actual orifice area, 34.3 mm (1.350 in) bore
Diameters and areas are Mercer's actual orifice sizes from its published model specifications, which run larger than the API 526 letter areas. Relieving capacity also depends on the certified flow coefficient, so confirm sizing with the workshop.
Quote this orifice →Pressure check
Will a 9500 cover your set pressure?
Type your set pressure. If it falls outside the range, we'll point you at the series that covers it.
Enter a set pressure above zero.
Covered
Auto Seat Technology®
What's inside a 9500
The Auto Seat features that do most of the work in this series.
Fully guided disk
Keeps the disk aligned with the nozzle so it seats and seals on every pop.
Mechanical stops
The disk opens to the same point each pop, for the same capacity every time.
Non-rising stem
Stops torque from the adjustment screw reaching the disk and seat, extending valve life.
Already running 9500s?
Recertify them in Brisbane
- Tested as found, with a report on every valve
- Gas service on gas, liquid service on water
- Back on site ready to install, under the Inland Transport Guarantee
Book a recert →or call the workshop on 07 3265 4888
Documents
Manuals, data sheets and certificates
Everything for the 9500, downloadable from this site.
IOM
Installation and maintenance manual
How to install, operate and maintain the 9500.
Download
Data
Data sheet
Dimensions, orifice areas, materials and pressure ratings.
Download
Cert
Sample verification certificate
The certificate that comes back with every recertified valve.
Download
Warranty
Australian warranty
Mercer Brisbane 1 year and 3 year warranty terms.
View terms →
Other Australian series
Not quite the right valve?
Request a quote
Build your 9500 quote
Four quick steps. We'll come back with price and lead time from Brisbane. Or call 07 3265 4888.