Cla-Val 501A User Manual

INSTALLATION / OPERATION / MAINTENANCE

DESCRIPTION

The Cla-Val Model 501A Wafer Swing Check Valve combines low
head loss characteristics and a compact space saving design. It
is intended for use with a wide variety of fluids including water, oil,
gas, and steam. The 501A Check Valve is designed for installa­tion between ANSI flanges centered and supported by the flange
bolts.

INSTALLATION

The Cla-Val 501A Check Valve is designed to fit between ANSI
Class 125 and Class 150 Flanges (flat face). Two standard flange
gaskets for each valve are recommended.
Determine minimum bolt/stud length by adding check valve length
to ANSI bolt length. ANSI bolt length can be found in the following
standards: For Class 125 use ASME/AWWA/ANSI standard
B16.1, or For Class 150 use ASME/AWWA/ANSI standard B16.5.

The Cla-Val 501A Check Valve is installed between pipe flanges
with the nameplate or eye bolt on top and with the flow arrow indi­cating the "free flow" direction. The 501A is intended for horizon­tal pipe installations, but can operate satisfactorily in vertical up
flow applications. See engineering data sheet E-501A for recom­mendations.

During flowing conditions the clapper swings into the downstream
piping. To avoid valve damage this piping must be: 1.) full internal
pipe diameter, 2.) without internal mechanical obstructions, and

3.) straight for a minimum of 3 pipe diameters from the valve out­let.

The valve is supported between the flanges by long flange bolts
and nuts or studs and nuts connecting the two pipe flanges. The
valve is centered to the pipe by the flange bolts. 12 " and larger
size valves are quite heavy, so some form of support is recom­mended.
Two customer supplied gaskets are needed.

1.) Before valve is installed, pipe line should be flushed of all
chips, scale, and debris.

2.) It is recommended that either gate or block valves be installed
near both ends of the 501A Check valve to facilitate isolating the
valve for preventative maintenance and repair.

3.) Verify flange dimensions match valve rating and dimensions.

4.) Loosely install lower half of the flange bolts with gaskets on

both flanges.

MODEL

Series 501A

Wafer Swing Check Valve

OPERATION

The standard soft seat provides a drip tight seal and the quick
spring assisted closure minimizes the possibility of water hammer.
The clapper initiates closure before flow reversal to prevent any
surges created by the check valve closure.

MAINTENANCE

Due to the low wearing working parts and simple construction the
501A Check valve will provide many years of trouble free service.
However, for critical applications or for preventative maintenance,
an annual visual inspection is recommended.

The primary symptom that signals the need for valve servicing is
when the synthetic rubber seal (Nitrile or Viton) which can wear
during service eventually creates a small leaking condition in the
check direction. Valves subject to a high frequency of operations
may require spring replacement at earlier intervals. This should
become apparent when valve closure is noisy.

1. Caution. It should be realized that the valve cannot be serviced
under pressure. Steps should be taken to remedy this situation
before proceeding any further.

2. Removal from the pipe line for maintenance only requires the
removal of upper half of the flange bolts and the lower half being
loosened only.

DISASSEMBLY

1. Remove valve from pipe line.

2. Lay valve down with clapper assembly facing upwards (flow

arrow pointing up). Protect valve from damage.

3. Remove pipe plug.

4. Remove hinge pin. Slightly compress spring with hand tools to

allow easy removal.
One end of the hinge pin is threaded to assist in removal. Install
a mating threaded rod to serve as a tool when removing pin.

5. Carefully lift clapper and hinge arm assembly out of valve. Do
not damage seating surfaces of valve body. On larger valves it
may be easier to unbolt clapper from hinge arm.

6. Remove two thrust washer bushings and spring.

7. Remove 'O' ring seat seal in valve body with a small hand tool.

5.) Lower 501A Check Valve between flanges and gaskets with

nameplate or eye bolt upwards and centered until it is resting and
supported by lower bolts. Note flow arrow
orientation to be sure it is correct for the application.

6.) Install remaining upper bolts and tighten in a “cross-over” pat­tern until no leaks appear.

8. Inspect all parts for signs of wear or damage. Replace if nec­essary.

REASSEMBLY

1. Reassembly is basically the reverse of disassembly steps.

2. Clean all parts.

3. Lay valve body down with seat and hinge arm cavity facing
upwards. Use care to prevent damage.

4. Replace two bushings in valve body after using a very small
amount of waterproof grease on the inside of the bushings.

5. Install new 'O' ring seat seal in dovetail groove in valve body.
The groove is slightly larger in diameter than the 'O' ring to secure
'O' ring in place. Lubricate the 'O' ring with a very small amount of
waterproof grease before installing. Stretch 'O' ring and place or
"pop" it into groove at two opposite locations. Then push remain­der of 'O' ring into the groove by hand pressure making sure that it
is in flat and not twisted.

6. Carefully place clapper and hinge arm assembly into body with
seating surfaces together. Line up hinge arm holes, bushings, and
hinge arm cavity of body.

A

DIA.

C

DIA.

Q

7. Lubricate hinge pin with a very small amount of waterproof
grease and reinstall (using threaded rod tool) from the outside
through body, first bushing, and part of hinge arm.

8. Carefully compress torsion spring slightly and place in center of
hinge arm cavity. Insert hinge pin through spring, remaining part of
hinge arm, and second bushing. Be sure that threaded end of
hinge pin can be seen from the outside of the valve body.

9. Replace plug.

10. Check valve for freedom of movement. Place valve in a verti-

cal position with hinge pin at top. Move clapper assembly by hand
through full stroke. Larger valves should be supported to prevent
valve overturning and causing damage.

11. Conduct leak test if possible.

12. Reinstall valve in pipeline

B D

FLOW

16

(In Inches)

13

⁄16 59 2 3.1

1

4 1⁄2 9 1⁄2 7 3⁄8 65 11 3⁄4 72.6

⁄8

EyeBolt

Dimensions

Size A B C D E (Deg.) Q Wt.Lbs.

2 4 1⁄8 1 11⁄16 1 3⁄8

2 1⁄2 4 7⁄8 1 13⁄16 1 3⁄4 1 1⁄16 60 2 7⁄8 4.2

3 5 3⁄8 2 1⁄2 2 3⁄8 1 1⁄8 62 3 6.6

4 6 3⁄4 2 1⁄2 3 1⁄8 1 5⁄8 60 4 8.1

5 7 3⁄4 2 3⁄4 3 7⁄8 2 1⁄2 61 5 12.3

6 8 3⁄4 3 4 1⁄2 3 3⁄4 72 6 18

8 11 3 1⁄2 6 1⁄4 4 3⁄4 70 7 3⁄4 27.3

10 13 3⁄8 4 1⁄2 7 5⁄8 5 3⁄4 66 9 3⁄4 51.3

12

11

9

10

3
8

5
7

4

Series 501A - Wafer Swing Check Valves

2

(Standard) 2" - 12"

Technical Data

Pressure Rating: 235 Max psi

Temperature Range:-5º to 210º F

Disc Cracking Pressure: All Valves equal

approximately 0.5 psi

Fluids: Water, Wastewater, Chemicals and

Petroleum

For a more detailed IOM Manual go to www.cla-val.com or contact a Cla-Val Regional Sales Office.

P.O. Box 1325 • Newport Beach, CA 92659-0325 • Phone: [phone] • Fax: [phone] • E-mail: [e-mail] • Website cla-val.com

©

CLA-VAL

Copyright Cla-Val 2011 Printed in USA Specifications subject to change without notice.

No. Description Material Specifications

1 Body Cast Iron or Steel ASTM A48 / ASTM A216
2 Disc 316 Stainless Steel ASTM A473 / A743M- CF8M
3 Shaft 316 Stainless Steel ASTM A276
4 Plug 304 Stainless Steel ASTM A276
5 Seat (Shaft) PTFE ­6 Seat (Body) Nitrile or Viton
7 Bushing 316 Stainless Steel ASTM A276
8 Travel Stop 316 Stainless Steel ASTM A276
9 Ta g Aluminum -

10 Spring 304 Stainless Steel -

TM

Commercial

6

1

N-501A