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R-Series

R-Series Relief Valves

How The R-Series Works

The R-Series & the 10691-Series Back Pressure & Relief Valves relieve upstream pressure in a variety of  processes. R-Series has a stainless steel disc and the 10691-Series has a soft elastomeric disc for tight shut-off. These valves automatically maintain desired maximum pressure in a vessel or system by relieving excess pressure into lower pressure return line or to atmosphere. Ideally suited for use as pump bypass control valve by maintaining constant pump discharge pressures. Used as a continuously operating valve or for protection against intermittent over-pressure conditions.

Controlling Pressure

The Relief Valve is actuated by the system pressure on the inlet side of the valve. Valve loading is provided by a spring. The adjustment is done by removing the cap and rotating the screw clockwise or counter-clockwise. Spring load balances against the opening force of the up stream (or relief) pressure. Valve will open at the slightest increase in pressure above the spring set point, and will close when the excess pressure has been relieved. The higher the system pressure is above the relief set point pressure, the more flow the valve will pass. It is therefore typical to specify the maximum capacity of a back pressure relief valve at 10% and 20% over set pressure

Simple in Design

To adjust set pressure of valve, remove top cap, loosen lock nut and adjust pressure by rotating adjustment screw. Rotating the screw clockwise increases the compression on the spring thereby increasing the set pressure. Rotating the screw counterclockwise lowers the set pressure. Tighten the locknut and replace top cap and gasket.

Simple in Design

To adjust set pressure of valve, remove top cap, loosen lock nut and adjust pressure by rotating adjustment screw. Rotating the screw clockwise increases the compression on the spring thereby increasing the set pressure. Rotating the screw counterclockwise lowers the set pressure. Tighten the locknut and replace top cap and gasket.

Setting Points of Flow

The Relief Valve remains closed until the Set-Pressure is reached. When the Set-Pressure is met or exceeded, the spring will  compress, allowing the valve to open and flow to occur.It is therefore typical to specify the maximum capacity of a back pressure relief valve at 10% and 20% over set pressure.

Setting Points of Flow

The Relief Valve remains closed until the Set-Pressure is reached. When the Set-Pressure is met or exceeded, the spring will  compress, allowing the valve to open and flow to occur.It is therefore typical to specify the maximum capacity of a back pressure relief valve at 10% and 20% over set pressure.

How To Size

The Relief Valve remains closed until the Set-Pressure is reached. When the Set-Pressure is met or exceeded, the spring will compress, allowing the valve to open and flow to occur. It is standard practice to publish flow values at 10% and 20% over the Set-Pressure.

Example

Application:  A 3/4" R Valve set at 50 PSIG will pass 2 GPM of water if the system pressure exceeds the set point by 20%.
Model Code: R-13-N-2 ( R Series, 3/4” NPT, 25-100 PSIG spring range, EPDM disc with a Factory Set Relief Pressure of 50 PSIG)


Full Capacity Chart

Model Coding for R-Series

Example Model Code with Set-Pressure Option:

R-12-N-2, Set at 50 PSI
(R Series, 1/2” NPT, 25-100 PSIG Spring Range, with a Factory Set Relief of Pressure of 50 PSIG)

 

Factory Setting of Relief Pressure Option:
Specify Set-Pressure when ordering. Add desired factory set pressure to the end of the model code, See Example above.

R-Series - RELIEF & BACK PRESSURE VALVES

Water, Liquids: Relief & Back Pressure Valves, The R Series & 10691 Series are economically-priced Back Pressure Relief Valves for Liquid service. Relief Valves/Back Pressure Valves are used to maintain a specific back pressure or to protect systems from an over-pressure condition.

ModelSizeTypeRelief Pressure (psig)Disc MaterialMax Inlet Pressure (psig)Capacity (gpm)Weight (lbs)
R-12-N-41/2"NPT1 - 6Stainless Steel3001.5
R-12-N-31/2"NPT w/ Union5 - 35Stainless Steel3001.5
R-12-N-11/2"NPT75 - 300Stainless Steel3001.5
R-12-N-21/2"NPT25 - 100Stainless Steel3001.5
R-12-N-11/2"NPT75 - 300Stainless Steel3001.5
R-13-N-43/4"NPT1 - 6Stainless Steel3002.5
R-13-N-33/4"NPT5 - 35Stainless Steel3002.5
R-13-N-23/4"NPT25 - 100Stainless Steel3002.5
R-14-N-11"NPT75 - 300Stainless Steel3003.3
R-13-N-13/4"NPT75 - 300Stainless Steel3002.5
R-14-N-41"NPT1 - 6Stainless Steel3003.3
R-14-N-31"NPT5 - 35Stainless Steel3003.3
R-14-N-11"NPT75 - 300Stainless Steel3003.3
R-15-N-41 1/4"NPT1 - 6Stainless Steel3004.5
R-15-N-31 1/4"NPT5 - 35Stainless Steel3004.5
R-15-N-21 1/4"NPT25 - 100Stainless Steel3004.5
R-15-N-11 1/4"NPT75 - 300Stainless Steel3004.5
R-16-N-41 1/2"NPT1 - 6Stainless Steel3006.3
R-16-N-31 1/2"NPT5 - 35Stainless Steel3006.3
R-16-N-21 1/2"NPT25 - 100Stainless Steel3006.3
R-16-N-11 1/2"NPT75 - 300Stainless Steel3006.3
R-17-N-32"NPT5 - 35Bronze30010.3
R-17-N-22"NPT25 - 100Bronze30010.3
R-17-N-12"NPT75 - 300Bronze30010.3
R-19-N-33"NPT5 - 35Bronze30025
R-19-N-23"NPT25 - 100Bronze30025
R-19-N-13"NPT75 - 300Bronze30025
R-12-N-31/2"NPT w/ Union5 - 35Stainless Steel3001.5
Downloads
Catalog Spec Sheet (pdf)
I&M (pdf)
Condensed I&M (pdf)
Product Overview
The R-Series Back Pressure & Relief Valves relieve upstream pres sure in a variety of processes. R-Series has a stainless steel disc. This valve automatically maintain desired maximum pressure in a vessel or system by relieving excess pressure into lower pres sure re turn line or to atmosphere. Ideally suited for use as pump bypass control valve by maintaining constant pump discharge pressures. Used as a continuously operating valve or for protection against intermittent over pressure conditions.

The R-Series Back Pressure Relief Valves are used in the following applications :
• Water pump bypass for irrigation, sprinkler systems on golf courses, fountains and fire protection systems.
• Fuel oil pump bypass on commercial systems or large residential systems.

NOT TO BE USED ON STEAM.
Features
• Four Springs – easily interchanged to cover pressures from 1 to 300 PSIG
• Heavy-duty bronze valve body
How It Works
The Relief Valve is actuated by the system pres sure on the inlet side of the valve. Valve loading is provided by a spring. The adjustment is done by removing the cap and rotating the screw clockwise or counter-clockwise. Spring load balances against the opening force of the upstream (or relief) pressure. Valve will open at the slightest increase in pressure above the spring set point, and will close when the excess pressure has been relieved.

The higher the system pressure is above the relief set point pressure, the more flow the valve will pass. It is therefore typical to specify the maximum capacity of a back pressure relief valve at 10% and 20% over set pressure.

Pressure Adjustments
To adjust set pressure of valve, remove top cap, loosen lock nut and adjust pressure by rotating adjustment screw. Rotating the screw clockwise increases the compression on the spring thereby increasing the set pressure. Rotating the screw counterclockwise lowers the set pressure. Tighten the lock nut and replace top cap and gasket.

Selection / Sizing / Capacities
The Relief Valve remains closed until the Set-Pressure is reached. When the Set-Pressure is met or exceeded, the spring will compress, allowing the valve to open and flow to occur. It is standard practice to publish flow values at 10% and 20% over the Set-Pressure.

Example:
A 1” valve set at 50 PSIG will pass 3.1 GPM if the system pressure exceeds the set point by 20%.

The R Series Relief Valve water capacities at inlet pressures of 10% and 20% over Set-Pressure:
Options

R-Series Spring Selection Table (* Relief Pressure 1 - 6 PSI is available on 1/2" - 1-1/2" ONLY)

Dimension and Weights
Pipe-Size
1/2" - 1 1/2"

Pipe-Size
2" - 3"