Gauge Valves and Pressure Gauge Accessories
General Features
Gauge Protectors I Features and Benefits
AS-Schneider Gauge Protectors are used to protect pressure-sensing instruments against damage, loss of accuracy, and/or rupture in the event of excessive system pressure. The piston assembly works against an adjustable spring. The piston assembly contains a sealing mechanism to isolate system pressure from the instrument.

The Inlet to Outlet seal is an O-Ring, the sealing to atmosphere is realized by either another O-Ring (system pressures of more than 2 bar) or a diaphragm (for system pressures 0.4 up to 2.5 bar). As system pressure overcomes the force of the spring, the piston moves, causing the sealing system to close. The outlet side is now isolated from increasing system pressure and the instrument is protected. As system pressure drops to the reopening pressure (25% below the closing pressure), the valve opens again.

Standard Features

  • Forged Body
  • Piston Seals:
    - FKM (FPM by ISO)
    - Diaphragm in NBR for the DVGW approved type
  • Maximum allowable pressure (PS) 600 bar
  • Maximum Inlet Pressure 1,000 bar (except Brass Type: 600 bar)
  • Maximum allowable temperature (TS) 80°C, resp. 60°C for our DVGW approved types S005.50.001.00DV / 201.00DV

The Gauge Protectors are as a standard available for sour gas service in accordance with NACE MR0175/MR0103 and ISO 15156 except the Brass Type.

Pressure Test:
A shell test and a seat test are performed at 1.5 times the maximum working pressure acc. to EN 12266-1 - P10, P11 and P12. The closing pressure is normally adjusted to the average value of the relevant adjusting range – For example adjusting range 2-6 bar = 4 bar closing pressure.
Optional Features

DVGW approved Gauge Protectors:
AS-Schneider is offering Gauge Protectors which have been tested and approved by DVGW. The test basis is DVGW VP 308. The valves are applicable for all kinds of gas in accordance with DVGW-list number G 260.

Pressure-Temperature Rating:

  • Max. 400 bar @ -20°C up to +60 / +80°C

  • DVGW-Approval-No.: DG-4515BP0208
  • Part No. Suffix ...00DV for DVGW types

Oxygen Service:
AS-Schneider offers an option cleaned and lubricated for Oxygen Service – Suffix F0:

  • Max. allowable (Working) Pessure (PS): 400 bar
  • Max. allowable (Working) Pessure (TS): 60°C

  • A choice of O-Ring materials is available.

Inspection certificate 3.1 acc. to EN 10 204 for valve body material and pressure test available on request.

Components Brass Stainless Steel Duplex Alloy 400 Alloy C-276 Alloy 625
Material / Material No.
Body Brass 1.4571 | 316 * Duplex Alloy 400 Alloy C-276 Alloy 625
Bonnet 316 * Duplex Alloy 400 Alloy C-276 Alloy 625
Piston 1.4404 * 1.4404 * | 316 * Duplex Alloy 400 Alloy C-276 Alloy 625
Piston Seals FKM (FPM by ISO)
Screw Plug 1.4404 * 1.4404 * Duplex Alloy 400 Alloy C-276 Alloy 625
Adjusting Screw 1.4404 *
Spring Stainless Steel
Adjusting Nut Unalloyed Steel Stainless Steel

* 316 / 316L / 1.4401 / 1.4404

Gauge Protector Type S005.50

Gauge Protector Desing
For System Pressures
2 - 600 bar

Gauge Protector Design
For System Pressures
0.4 - 2.5 bar
Gauge Protector Type N005.50
Screwed Bonnet Design
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