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Deringer 40G (RP)

Reduced Pressure Backflow Preventer w/ OS&Y Gate Valves

SKU
Deringer 40G
MSRP: $12,499.00 MSRP: $12,499.00 Pro Price: $2,419.00 Pro Price: $2,419.00 Special Price $0.00
Price includes standard ground shipping.

The Deringer 40G Reduced Pressure Backflow Preventer w/ OS&Y Gate Valves prevents non-health hazard pollutants from entering a potable water supply system when backpressure and/or backsiphonage conditions occur.

The smallest, lightest, most economical, best performing, and only all stainless steel backflow preventer. Period.

Deringer Approvals

Deringer 40G(X) Reduced Pressure Valves prevent non-health hazard pollutants and hazardous contaminants from entering a potable water supply system when backpressure and/or backsiphonage conditions occur. Used primarily on fire sprinkler systems when monitoring of unauthorized water use is required.

Deringer 40G

Maximum Working Pressure: 175psi (12.1 bar)
Temperature Range: 33 to 140 deg F (1 to 60 deg C)
Lead Free: 0.25% Maximum by Weight

End Connections:
Flange Adapters: ANSI B16.1 Class 125
IPS Groove for Steel Pipe: AWWA C606

Rate of Flow:

Rate of Flow Deringer 40G

Dimensions:

Deringer 40G measurements

Materials:

Valve Housing: 304 Stainless Steel
Valve Cover: 304 Stainless Steel
RV Spring: 302 Stainless Steel
Non Wetted Bolts: Grade 8 Zinc Plated
Check Disks: Silicone
Wetted Fasteners: 18-8 Stainless Steel
RV Housing: 304 Stainless Steel
Check Springs: 17-7 Stainless Steel
Check Pins: 17-7/18-8 Stainless Steel
Check Seats: Noryl Polymer
O-Rings: Buna-N
RV Hose: Braided Stainless Steel Wire
Gate Valve: Stem includes tamper switch groove
Gate Valve: Serviceable inline
Gate Valve: AWWA C509/UL/FM resilient seat (OS&Y)
Gate Valve: Flanged End ANSI B16.1 Class 125
Coupling: Flexible Grooved UL/FM

Engineering Specifications

The Deringer 40G Reduce Pressure (RP) Valve shall utilize two independent Dual Action Check modules contained within a single valve housing constructed of entirely of stainless steel. Dual Action Check modules shall operate as a poppet style check under low flow conditions, operate as a swing style check under high flow conditions and utilize replaceable silicone elastomer sealing discs. Valve assembly shall include two resiliently seated and inline serviceable AWWA C509 gate valves of type outside yoke and stem (OS&Y). Gate valves shall utilize a stainless steel stem with a pre-machined groove for installation of supervisory tamper switches. Assembly test cocks shall be handle-less and operate via a tamper resistant actuator. Assembly shall utilize a single full access service port and a cover with an inline replaceable elastomer seal. Relief valve shall operate without the use of sliding seals and shall be constructed entirely of stainless steel. Assembly shall be serviceable without the use of special tools.

Maximum Relief Valve Discharge Rates

Deringer 40G Max Discharge

Deringer Specification Sheets

The Deringer 40G Specification Sheet includes information on valve characteristics, flow performance data, approval status and engineering specifications for all sizes. This file can be downloaded as a PDF and saved for future use.

Deringer 40G Specification Sheet

Maintenance Instructions

The Deringer 40G/50G Maintenance Instructions provide step by step procedures for maintaining a 2 to 4 inch Deringer 40G/50G backflow preventer. A printable PDF document is available.

Deringer 40G/50G Maintenance Instructions

Maintenance Video - 2 to 4" Deringer 40

Tamper Switch Procedure

The Deringer Gear Box Tamper Switch Procedure provides a step by step instructions for positioning the wiring of the Deringer gear box for fire alarm protection. A printable PDF document of these instructions is available.

Tamper Switch Instruction

True-Seal Check Modules

The True Seal Check Valve was designed to incorporate a poppet only motion during the check stroke and is used exclusively on the first check assembly on the Deringer RP and RPDA models and Magnum RP model. This design allows a more consistent pressure loss across the check valve which helps maintain a steady and continual closure of the Relief Valve.

  • Light weight engineered polymer components
  • Modular for easy removal of complete check from body
  • Easily disconnect spring tension for safe check servicing
  • Replaceable Silicone Rubber Elastomer Disk
  • Excellent resistance to fouling.
True-Seal Check Modules

Poppet Action

Deringer and Magnum 40/50 Low Flow Poppet Action

Features:

  • 100% of check stroke is that of a poppet check
  • Consistent static sealing
  • Excellent resistant to fouling
  • Reliable check closure
  • Stable flow characteristics at ALL flow rates

Dual-Action™ Check Modules

The Patented Dual-Action Check™ (US8875733) is the core technology behind the superior performance of Deringer Backflow Prevention Product Line. The Dual-Action Check™ combines all of the best features of industry standard “poppet” checks and “swing” checks into a single high performance check module.

  • Light weight engineered polymer components.
  • Modular for easy removal of complete check from body.
  • Easily disconnect spring tension for safe check servicing.
  • Replaceable Silicone Rubber Elastomer Disk.
  • Excellent resistance to fouling
Dual Action Check Module

Poppet Action

Low Flow Poppet Action

Features:

  • Initial 25% of check stroke is that of a poppet check
  • Consistent static sealing
  • Excellent resistant to fouling
  • Reliable check closure
  • Stable flow characteristics at lower flow rates

Swing Action

Features:

  • Final 75% of check stroke is that of a swing check
  • Minimal friction loss at high flow rates
  • More linear flow path water through valve.
High Swing Action

Bow-Seal™ Full Access Cover

The Patented Bow-Seal™ Full Access Cover (US8844562) is pre-formed to cylindrical shape friendly to high fluid pressure. This allows the cover to be much thinner and lighter than traditional flat covers while still providing FULL and EASY access to Dual Action™ Check Modules.

Additional features include:

  • Light weight Simple removal
  • No sliding seals
  • Full access to valve internals
  • No cumbersome and heavy couplings
Bow Seal Access Cover

Tamper Resistant Test Cock

The Deringer tamper resistant 1/2" and 3/4" ball valves are the first handle-less test cocks found on large diameter backflow devices in the industry. The top of the valve actuation stem has a unique shape that uses an independent custom wrench to open and close test cocks. All test cocks are lead free and meet the SDWA requirements.

Deringer Tamper Resistant Test Cock

Relief Valve

The Deringer 40/50 Relief Valve uses a stainless steel body, piston seal and stainless steel sensing line and has been designed to be the smallest and lightest Relief Valve in the industry. Unlike previous relief valve designs, the piston seal does not use the body of the relief valve to align itself properly when closing and opening and instead uses the guide pin on the piston. This will aid in making the Relief Valve resistant to build up and binding. All components of the relief valve are lead free and meet the SDWA requirements.

Relief Valve Image