Cla-Val RP2M User Manual

Shipboard Backflow Preventer

Principle of Operation

When a normal flow condition exist, both Check Valves are open and
the pressure Differential Relief Valve is closed.

When flow ceases, both Check Valves close and pressure in the
zone between the Check Valves is maintained at least 2 PSI lower
than inlet pressure. Should inlet pressure drop to 2 PSI or less, the
Pressure differential Relief Valve opens the zone between the Check
Valves to atmosphere.

When a backflow condition, exists, the Pressure Differential Relief
Valve will open to maintain the zone pressure at least 2 PSI less than
the inlet pressure.

MODEL

RP-2M

• Positively Protects Potable Water Lines Against

the Hazards of Contamination due to Cross
Connection

• Minimum Head Loss

• Reduced Pressure Principle - Maximum Backflow

Protection

• Shock and Vibration Qualified to MIL STANDARDS

The Model RP-2 M Shipboard Backflow Preventer protects potable
water lines against contamination. This device combines protection
against backflow with exceptionally low head loss. It operates on the
reduced pressure principle, which is the accepted method of
safeguarding potable water supplies against the hazards of cross
connection.

The Model RP-2M is carefully constructed of corrosion-resisting
materials. It consists of two independently acting Poppet-Type Check
Valves and an automatic Pressure Differential Relief Valve located
between the two check valves.

The automatic Pressure Differential Relief Valve is designed to open
on a decreasing differential. It is closed whenever the inlet pressure
is 2 to 3 PSI higher than the pressure in the zone between the two
check valves. Pressure sensing is through internal porting for reliable
operation.

Installation

The Cla-Val Model RP-2M is designed to be installed in a horizontal
position with the Pressure Differential Relief Valve discharging
vertically down. Right hand mount of the Relief Valve is standard. Left
hand mount of the Relief Valve is available at extra cost. Adequate
drainage with appropriate air gap provisions must be provided for
Relief valve discharge,

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Specifications

PO Box 1325 Newport Beach CA 92659-0325

Phone: [phone] Fax: [phone]

CLA-VAL

CLA-VAL CANADA CLA-VAL EUROPE

4687 Christie Drive
Beamsville, Ontario
Canada L0R 1B4
Phone: [phone]
Fax: [phone]

Chemin dés Mesanges 1
CH-1032 Romanel/
Lausanne, Switzerland
Phone: [phone]
Fax: [phone]

©COPYRIGHT CLA-VAL 2013 Printed in USA

Specifications subject to change without notice.

www.cla-val.com

Size: 3/4", 1", 1 1/4", 1 1/2"

End Detail:

Threaded: ANSI B 16.15

Maximum Working Pressure:

150 psi

Max. Temperature:

to 110°F

Dimensions (In Inches)

Fluid: Potable Water/ Seawater

Hydrostatic Test Pressure:

to 300 psi

Military:

Shock qualified to MIL-S-901C
Vibration Qualified to MIL-STD-167B

Material:

Main Body Valve and Cover:

Bronze ASTM B-61

Main valve trim:

Monel & Delrin

Seals:

Buna-N

Diaphragm:

Nylon Reinforced Buna-N

SIZE A

3/4" 11.60 3.65 6.00 15

1" 11.44 3.65 6.00 15

1-1/2" 14.81 4.00 6.19 25

We recommend providing adequate space around assembly for maintenance work and testing.

B

(Max.)

C

(Max.)

WT.LBS

The reduced pressure principle backflow preventer shall
consist of two independently acting spring-loaded check
valves and an automatically operating pressure differential
relief valve, and shall have provision for installing properly
located test cocks. Operation shall be completed
automatic. All internal parts of the spring-loaded check
valves and the pressure differential relief valve must be
removable or replaceable without removal of the backflow
preventer form the line. the total head loss at rated flow
rate through the complete backflow preventer assembly

shall not exceed (select values as shown in the table). The
reduced pressure principle backflow preventer shall be the
Model RP-2M Shipboard Backflow Preventer as
manufactured by Cla-Val, Newport Beach, California.

Valve Size Rated Pressure Drop

in Inches Flow in PSI

3/4” 30 12.8

1” 50 12.25

1 1/2” 100 13.5

Flow Curves

3/4" Model RP-2

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Flow curves generated by the Foundation for Cross-Connection Control and Hydraulic Research University of Southern California.
*”Metered Rated Flow" Values adopted by the American Water Works Association and the New England Water Works Association

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E-RP-2M (R-1/2013)

20

15

10

5

HEADLOSS-PSI

0

Meter Rated Flow*

1" Model RP-2

20 40 60 80

FLOW-GPM

50

50
RF

1-

" Model RP-2

1/2

Represented By: