Cla-Val DBJ User Manual

Duckbill Check Valves

Installation, Operation and

Maintenance Instructions

DBF Flanged Style

DuckBill Check Valve

DBJ Jacket Style

DuckBill Check Valve

CLA-VAL

DBO Slip-Over Style

DuckBill Check Valve

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

©

Copyright Cla-Val 2014 Printed in USA Specifications subject to change without notice.

DBI In-Line Style

DuckBill Check Valve

OPERATION

DBO/DBJ

DBI

DBF

Cla-Val Duckbill Check Valves are custom made and are intended for specific applicaons. They are designed to
respond to criteria unique to their purpose, such as line pressure, backflow pressures, and chemical compability.
Should the condions be altered or changed significantly, it could affect the normal operaon of the valves.

Cla-Val Duckbill Check Valves operate based on differenal pressure. When the line pressure (at the valve inlet)
exceeds the backpressure (at the valve outlet), the valve o

pens and flow is created. When the backpressure
exceeds or overcomes the line pressure, the bill of the valve seals shut, thereby prevenng any backflow from
occurring.

TERMINOLOGY (refer to diagrams below)

Cu: The round poron of the valve from taper to the flange (where applicable).
Taper: The taper transforms the round shape of the valve cuff to the vercal shape of the valve bill. Reinforcement in the taper is customized to suit each

Bill: The outlet end of the valve. The bill contorts to allow flow through the valve yet closes ght during ‘n

Tube: The inner surface. This is constructed using an elastomer that is most suitable for the process fluid.
Cover: The outer surface of the valve. This is made from an elastomer that is most suitable for the external environment.
Retaining Ring: Supplied with the valve, the duckbill flange is ‘sandwiched’ between the mang pipe

Supplied with the valve, the duckbill cuff is squeezed between the mang pipe and the clamp(s) (inside or outside of the pipe).

Clamps:
Line Pressure: The fluid pressure applied to the valve inlet (used to open the valve).
Backpressure: The fluid pressure exerted on the valve outlet. It is usually measured in feet or metres of fluid above the pipe invert.

applicaon’s expected inlet pressures and backpressures.

o flow’ or reverse pressure condions. The

bill can be straight or curved, depending on the applicaon.

flange and the retaining ring.

DBF/DBJ

INSTALLATION

Ensure that pipelines have been depressurized prior to installation, removal, or servicing the check valve. For best performance,

bills should be installed as close to the vercal posion as possible. In cases where clearance below the pipe outlet is minimal, the
duckbill should be rotated only enough as required to avoid contact with the ground. Please contact your Cla-Val representave
or the Cla-Val factory at 800.932.6326 directly to discuss this applicaon.

DBF/DBI INSTALLATION

1. Do NOT install against raised-face flanges (only to smooth-face flanges). Remove all burrs or sharp edges from the pipe flange faces and

wipe clean of oil, grease, etc. Apply a thin coat of graphite or glycerine to the pipe flange face. This will ease installaon and allow for easy
removal at a later date.

2. Li the duckbill check valve into posion and align the bolt holes of the pipe flange, check valve flange and t he retaining ring. Ensure that the

check valve’s bill is oriented in a vercal posion.

3. Aer the duck

alignment. Aer the proper alignment has been obtained, install the remaining nuts and bolts using washers at the split holes (if the Check
Valve comes with a retaining ring).

4. Use two wrenches when installing the Check Valve. Tighten all flange bolts in a criss-cross paern similar to the one shown in Figure 2 to the

maximum torque recommended in Figure 3.

5. Do not weld near the Check Valve.

bill check valve and retaining ring (where applicable) are in the correct posion, push two (2) bolts through to ensure

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DB O INSTALLATION

1. The outer or inner surface of the pipe must be smooth and free of burrs and sharp edges. Before installing the valve, verify its

fit by measuring the ID or OD of the cuff and the ID or OD of the pipe.

2. Slide the clamp(s) along the pipe or leave them on the valve cuff for DBO valves. Do not ghten unl aer the valve is in place.

3. Slip a DBO evenly over the end of the pipe unl the enre length of the valve cuff is in contact with the pipe.

the check valve’s bill is oriented in a vercal posion.

E

nsure that

4. Aer the check valve is properly posioned, install the clamp(s). Where 2 clamps are required, they should be rotated 90 degrees relave to

each other. This will ensure that even pressure is distributed around the cuff. A thin coat of mild lubricant or glycerine may be applied on
the inner surface(s) of the clamp(s). This will reduce the fricon when ghtening the clamp(s).

5. Ensure that the valve is snug to the pipe and be careful not to over-torque the clamps.

a. The recommended torque values for gear clamps 1-¾” and smaller is 3-lbs. For sizes larger than 1-¾” the torque value is 5 -lbs or as

otherwise noted by the Cla-Val Technical Department.

b. For larger DBO valves that do not use gear clamps, the inner sets of nuts (Figure 1 – nuts 2

and 3) clamp the valve to the pipe. These nuts should be ghtened unl the slack is removed
from the rubber cuff and the valve cuff is snug against the outside of the p
wrench set at 10 -lbs, torque the nuts unl a snug fit is achieved. This will ensure the valve
cannot be physically removed from the pipe. For valves 32” and up, a 20 -lbs torque seng
is required. The outer sets of nuts (Figure 1 – nuts 1 and 4) lock the first set of nuts in place.
This will prevent the clamps from loosening on the valve.

ipe. With a torque

6. DO NOT use a lubricant to aid in the installaon of the valve onto or inside the pipe. It could cause

the valve to slip out of posion.

7. Metal clamps on large size check valves (12” and larger) are provided with drilled holes for anchor

bolts. These holes are used as a paern for drilling through the rubber and the ouall pipe. These
anchor bolts should be installed 90 degrees to the clamp and may also be used on smaller valves
provided that this requirement is discussed prior to valve manufacture. See “Securing DBO Check Valves”

(below) for clarity.

Figure 1

NOTE: Debris caught under a check valve can potentially aect its operation. Therefore,

between the bill of the valve and the ground during and after installation.

Securing DBO Check Valves

Anchor bolts are recommended to further secure the check valve into posion. Using the clamp(s) as a template, drill a hole(s) through the valve cuff
and through the pipe using a drill bit. Insert a stainless steel anchor bolt through the clamp hole, the cuff and the pipe and secure the anchor bolt
with stainless steel n
the installer to access the inside or outside of the pipe (to place the nuts on the anchor bolts), simply place the anchor bolt(s) into the hole(s) and tack
weld the anchor bolt to the clamp, thus creang a pin(s) to hold the valve. Exercise caution to minimize heat and splatter near the check valve and

perform welding away from the joint wherever possibl

ut, and washers. Anchor bolts are not supplied with the valves since pipes vary in thickness. For installaons that may not permit

e.

ensure that there is approximately 6” of ground clearance

DBO

DBJ INSTALLATION

Note: DBJ Split Body Design

- Downstream gasket required (not supplied with check valve).

- Do NOT install against raised-face flanges (only to smooth-face flanges).

1. Remove all burrs or sharp edges from the pipe flange faces and wipe clean of oil, grease, etc.

For DBJ Split Body Design

upstream pipe flange), apply a thin coat of graphite or glycerine to the
removal at a later date. No upstream gasket is required between the rubber duckbill flange and the mang pipe flange.

2. Li the duckbill check valve into posion, ensuring that the valve is oriented in the correct direcon of flow, (i.e. the bill end should be on the

downstream side of the valve). Align the bolt holes of the pipe and check valve flanges and ensure the check valve’s bill is oriented in a
vercal posion or as nearly vercal

3. Aer the duckbill check valve is in the correct posion, push two (2) bolts through each of the mang pipe flanges/check valve flange to

ensure alignment. After the proper alignment has been obtained, install the remaining bolts and nuts.

For DBJ Split Body Design - On the upstream flange of the duckbill check valve, (where the duckbill’s rubber flange will mate to the

upstream pipe flange) - ghten all flange bolts in a criss-cross paern similar to the one shown in Figure
recommended in Figure 3.

4. Do not weld near the Check Valve.

- On the upstream flange of the duckbill check valve, (where the duckbill’s rubber flange will mate to the
pipe flange face. This will ease installaon and allow for easy

posion as possible.

2 to the maximum torque

-

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Figure 2

err

Pipe Size ID (in)

Torque (ft-lbs)*

Torque (Nm)*

1 - 2

20

27

2.5 – 5

25

34

6 – 12

35

48

14 – 18

50

68

20 and larger

60

82

YES

NO

Figure 4b

*Torque settings are approximate and are as recommended by the Fluid Sealing Association Std FSA PSJ702
Flanged Non- Metallic Expansion Joint Installation, Maintenance and Storage” Manual.
a) To prevent leakage, the ange bolts should be retightened after one week of operation and checked periodically
thereafter.
b) Torque values are approximate. After installation, the system should be pressurized and examined to conrm a
proper seal.

Figure 3

STORAGE

• Duckbill check valves should be stored vercally ( Figure 4 a ) with the bill facing upward, not on their side (Figure 4b )

•

Check valves should be stored

Check valves should not be stacked, nor should anything be stored on top of their bills. They should remain on a skid unl ready for use.

•

•

Do not drop, bend, or twist the valve , as damage may occur.

•

The valve should be wrapped in black plasc to avoid contact with sunlight and/or ultra vi

•

Avoid exposure to light, electric motors, dirt, or chemicals. Resilient check valves are subject to deterioraon (hardening and becoming

in a cool, dry locaon with maximum venlaon.

olet light. This will extend the shelf life.

brile) when exposed to ozone and non-compable chemicals

06 “Rubb

Figure 4a

MAINTENANCE

Periodically, an inspecon should be performed to verify the valve’s performance:

• Inspect the tube and cover for cuts, checking, and fissures. Do not be alarmed if small cuts have formed in the outer cover. If necessary,

repairs can be made on site with a repair compound. If significant fissures are noced where fabric is exposed and torn, the valve must be
replaced. Please contact Cla-Val factory for assistance if necessary.

• If blisters, deformaon, or delaminaon is noted inside the valve, this is an indicaon that the media

are aacking the tube. The valve should be replaced as soon as possible. Please contact Cla-Val factory for assistance if necessary.

• Inspect the valve for entrapped foreign objects, which may have lodged between the lips of the valve and could prevent the valve from

checking.

• Clean out ports are provided on DBJ bodies to allow drainage of the valve prior to performing any inspecons or maintenance. (Note:

he valve body).

g t

For DBJ Split Body valves, the drainage ports are located mid-way

alon

• Verify that there is clearance between the boom of the bill and the ground and that no debris is trapped there.

If a build up of debris occurs within the valve, line pressure should flush it out. In some instances, a wooden plank 1” x 4” or 1½” x 12” may be

temporarily

inserted into the bill of the valve and rotated 90°. This will clear the check valve of any debris that may be trapped in the bill.

WARRANTY

All products supplied by Cla-Val -are guaranteed against defects resulng from faulty workmanship or materials
shipment to Buyer. If any such product is found to be defecve by reason of faulty workmanship or materials, then upon

wrien noce and return of the product, and at our sole discreon, the defe cve product will be replaced or repaired by us free of charge at our
factory. Claims for labour costs and other expenses required to replace and/or transport such defecve product or to repair damage resulng fr
the use thereof will not be allowed by Cla-Val. Our liability does not include consequenal damages and is limited to the price paid for the defecve
product.

Cla-Val shall not be bound by any other warranty other than the above set forth unless such warranty shall be agreed in wring by Cla-Val.

All Cla-Val literature is published in good faith and is believed to be reliable at me of print; however, due to product design changes, Cla-Val reserves
the right to make alteraons from published materials at any m
request at me of order.

e. Formal approval drawings are available to confirm individual products upon

or higher than expected temperatures

for one (1) year from date of

om

CLA-VAL

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

©

Copyright Cla-Val 2014 Printed in USA Specifications subject to change without notice.

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N-DB Series