Cla-Val 55L User Manual

MODEL

55L

Pressure Relief Valve

• UL Listed

• Factory Mutual Approved

• Direct Acting - Precise Pressure Control

• Positive Dependable Opening

• Drip Tight Closure

• No Packing Glands or Stuffing Boxes

• Sensitive to Small Pressure Variations

The Cla-Val Model 55L (UL Listed FM approved) Pressure Relief
Valve is a direct-acting, spring loaded, diaphragm type relief valve. The
valve may be installed in any position and will open and close within
very close pressure limits.

The Model 55L is normally held closed by the force of the compression
spring above the diaphragm. When the controlling pressure applied
under the diaphragm exceeds the spring setting, the disc is lifted off its
seat, permitting flow through the control. When control pressure drops
below the spring setting, the spring forces the control back to its
normally closed position. The controlling pressure is applied to the
chamber beneath the diaphragm through an external tube on the 55L.

Typical Applications

Fire Protection System Service

Using the
protection system or other closed
type system, prevents pressure
build-up whenever line pressure
exceeds the setting of the spring.
The valve will relieve excess
pressure to atmosphere preventing
damage to the distribution network.

Model 55L in a fire

Pressure adjustment is simply a matter of turning the adjusting screw to
vary the spring load on the diaphragm. The 55L is available in three
pressure ranges; 0 to 75 psi, 20 to 175 psi, 100 to 300 psi. To prevent
tampering, the adjustment cap can be wire sealed by using the lock
wire holes provided in the cap and cover.

Note: Also Available in Seawater Service Material

CLA-VAL 90-21

Model 55L

CLA-VAL 90-21

1.75

1.75

Specifications

Size 1/2" & 3/4" Threaded
Temperature Range Water, Air: to 180°F Max.
Materials

Body & Cover: Cast Bronze ASTM B62

Stainless Steel ASTM A743-CF-16Fa

Trim: Brass & Stainless Steel 303

Rubber: Buna-N

®

Synthetic Rubber

55L Basic Valve Dimensions

(In Inches)

UL Listed

55L Range

psi

Approximate Increase

for Each Clockwise Turn

of Adjusting Screw

20 to 175 28.0 psi

FM Approved

55L Range

psi

0 to 75

Approximate Increase

for Each Clockwise Turn

of Adjusting Screw

8.5 psi

20 to 200 28.0 psi

100 to 300 18.0 psi

Pressure Ratings Cast Bronze 400 psi Max.

Stainless Steel 400 psi Max.

Other Materials Available on special order

Adjustment Ranges 0 to 75 psi

20 to 200 psi

100 to 300 psi

Pressure
Setting
Adjustment
Screw
(Turn Clockwise
To Increase Setting)

7.44

Flow Loss Chart (Full Open Valve)

Flow of Water - Gallons Per Minute

Valve

Size

1/2"

3/4"

C

v

Factor

5 10 16 20 30

6 0.7 2.7 6 11 --

8.5 0.3 1.4 3.1 5.5 12.2

When Ordering, Please Specify

1. Catalog No. 55L

2. Valve Size

3. Adjustment Range Desired

4. Optional Materials

800-942-6326 Fax: [phone] Web Site: cla-val.com E-mail: [e-mail]

CLA-VAL CANADA

4687 Christie Drive
Beamsville, Ontario
Canada L0R 1B4

E-55L (R-9/2011)

Phone: [phone]
Fax: [phone]
E-mail [e-mail]

©COPYRIGHT CLA-VAL 2011 Printed in USA Specifications subject to change without notice.

PO Box 1325 Newport Beach CA 92659-0325

CLA-VAL EUROPE

Chemin des Mésanges 1
CH-1032 Romanel/
Lausanne, Switzerland
Phone: [phone]
Fax: [phone]
E-mail: [e-mail]

INLET

.71

0 to 75 and 20 to175 psi design

CLA-VAL

CLA-VAL UK

Dainton House, Goods Station Road
Tunbridge Wells
Kent TN1 2 DH England
Phone: [phone]
Fax: [phone]
E-mail: [e-mail]

1.75

3.50

4.50

CLA-VAL FRANCE

Porte du Grand Lyon 1
ZAC du Champ du Périer
France - 01700 Neyron
Phone: [phone]
Fax: [phone]
E-mail: [e-mail]

CLA-VAL PACIFIC

306 Port Hills Road (Level Two)
Woolston, Christchurh, 8042
NewZealand
Phone: [phone]
Fax: [phone]
E-mail: [e-mail]