CLA-VAL RF-DBF Instruction manual

INSTALLATION / OPERATION / MAINTENANCE
Rubber-Flex Duckbill Check Valves
Model RF-DBF
Model RF-DBI-IN Model RF-DBI-LH Model RF-DBJ
Model RF-DBI Model RF-DBO

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Table of Contents
1.0 Introduction....................................................................................................................................... 3
1.1 Model RF-DBF: Rubber-Flex Flanged Duckbill Check Valve .................................................... 3
1.2 Model RF-DBI: Rubber-Flex Flanged In-Line Duckbill Check Valve ........................................ 3
1.3 Model RF-DBO: Rubber-Flex Slip-On Duckbill Check Valve .................................................... 3
1.4 Model RF-DBI-IN: Rubber-Flex Slip-In In-Line Duckbill Check Valve..................................... 3
1.5 Model RF-DBJ: Rubber-Flex Jacket Style Duckbill Check Valve............................................... 4
1.6 Model RF-DBI-LH: Rubber-Flex Low Head Loss In-Line Duckbill Check Valve ..................... 4
2.0 Storage and Handling........................................................................................................................ 5
2.1 Storage .......................................................................................................................................... 5
2.2 Handling........................................................................................................................................ 5
3.0 Prior to Installation ........................................................................................................................... 5
3.1 Inspect the Received Check Valve................................................................................................ 5
3.2 Verify the System Parameters....................................................................................................... 5
3.3 Check Valve Mating Surface ........................................................................................................ 5
3.4 Safety Area.................................................................................................................................... 5
4.0 Installation......................................................................................................................................... 6
4.1 Rubber-Flex Check Valve Installation ......................................................................................... 6
4.1.1 ........................... 6
4.1.2 ................ 7
4.1.3 ................................7
4.1.4 ............ 8
4.1.5 ...................... 9
4.1.6 .... 10
4.1.7 Flange Bolt Torqueing (Model RF-DBF/RF-DBI/RF-DBJ & Flanged RF-DBI-LH) .......... 11
4.1.8 Anchor Bolts/Pins (Model RF-DBO/RF-DBI-IN/RF-DBI-LH).......................................... 11
5.0 Operation......................................................................................................................................... 12
6.0 Maintenance.................................................................................................................................... 12
7.0 Appendix A..................................................................................................................................... 13
7.1 Torque Data ................................................................................................................................ 13
7.2 Sample Torqueing Patterns ......................................................................................................... 13
Model RF-DBF: Rubber-Flex Flanged Duckbill Check Valve Installation
Model RF-DBI: Rubber-Flex Flanged In-Line Duckbill Check Valve Installation
Model RF-DBO: Rubber-Flex Slip-On Duckbill Check Valve Installation
Model RF-DBI-IN: Rubber-Flex Slip-In In-Line Duckbill Check Valve Installation
Model RF-DBJ: Rubber-Flex Jacket Style Duckbill Check Valve Installation
Model RF-DBI-LH: Rubber-Flex Low Head Loss In-Line Duckbill Check Valve Installation

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1.0 Introduction
1.1 Model RF-DBF: Rubber-Flex Duckbill Check Valve
This type of rubber check valve is designed to bolt directly to existing flanges or
new installations. Flanges are drilled to ANSI 125/150# standard but other drill
patterns are available upon request. This style of rubber check valve can be installed
in either vertical or horizontal applications.
1.2 Model RF-DBI: Rubber-Flex Flanged In-Line Duckbill Check Valve
This type of rubber check valve is designed to fit directly inside of existing piping
systems. The design is supplied with a flat face rubber flange which allows
installation between existing pipe flanges eliminating the requirement for a valve
body. Flanges are drilled to ANSI 125/150# standard but other drill patterns are
available upon request. This style of rubber check valve can be installed in either
vertical or horizontal applications.
1.3 Model RF-DBO: Rubber-Flex Slip-On Duckbill Check Valve
This type of rubber check valve is designed to easily slip over an existing pipe and
is affixed to the pipe with heavy duty stainless steel clamps. This style of rubber
check valve can be installed in either a vertical or horizontal orientation for most
applications. Note: External Clamp shown is of a general style and will change
depending on the size of the supplied check valve.
1.4 Model RF-DBI-IN: Rubber-Flex Slip-In In-Line Duckbill Check Valve
This type of rubber check valve is designed to slip directly inside of an existing pipe and is supplied with a stainless steel
expandable clamp to secure in place. This style of rubber check valve can be installed in either a vertical or horizontal
orientation for most applications.
Figure 4: Model RF-DBI-IN
Figure 1: Model RF-DBF
Figure 2: Model RF-DBI
Figure 3: Model RF-DBO
Cla-Val Rubber-Flex Duckbill Check Valves are designed to provide outstanding back-flow prevention; eliminating costly and unwanted
back-flow from rivers, oceans, storm water, and is an excellent choice for sewage diffuser systems. Cla-Val Rubber-Flex Duckbill Check
Valves are fully passive flow devices requiring neither maintenance nor any outside sources of power or manual assistance to operate. They
are offered as direct replacements for ineffective and maintenance ridden flap-type check valves as well as for new/existing construction
and custom applications. Each check valve is manufactured to exacting specifications ensuring a perfect fit and usability and is available in
a wide variety of elastomers to meet the design requirements of the application. This installation, operation and maintenance manual will
cover the general practices for the proper installation, operation and maintenance of the Cla-Val Rubber-Flex Duckbill Check Valves.
Model RF-DBF Rubber-Flex
Flanged Duckbill Check Valve
Model RF-DBI Rubber-Flex Flanged
In-Line Duckbill Check Valve
Model RF-DBO Rubber-Flex
Slip-On Duckbill Check Valve
Model RF-DBI-IN Rubber-Flex
Slip-In In-Line Duckbill Check Valve
RF-DBI-IN Mating Pipe

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Model RF-DBI-LH Rubber-Flex Low Head Loss
Flanged In-Line Duckbill Check Valve
1.5 Model RF-DBJ: Rubber-Flex Jacket Style Duckbill Check Valve
Model RF-DBI-LH: Rubber-Flex Low Head Loss In-Line Duckbill Check Valve
Figure 5: Model RF-DBJ
1.6
Figure 6: Model RF-DBI-LH Rubber-Flex Low Head Loss In-Line Duckbill Check Valve
Figure 7: Model RF-DBI-LH Rubber-Flex Low Head Loss Flanged In-Line Duckbill Check Valve
Note: For flanged versions of Model RF-DBI-LH Low Head Loss In-Line Rubber Check Valves the integrated rubber flange
can be located on either the inlet or discharge end depending on required installation orientation.
This type of rubber check valve is designed with a full metal enclosure (Model RF-DBJ Shroud) which allows easy
installation in existing piping systems. Flanges are drilled to ANSI 125/150# standard but other drill patterns are available
upon request.
Model RF-DBJ Shroud
This type of rubber check valve is designed to slip directly inside of an existing pipe with the supplied stainless steel expandable
clamp or retaining ring to secure in place; it can be fastened from either the inlet or discharge end of the valve. The standard
Model RF-DBI-LH valve must be installed in a truly round pipe. Out of round pipe may cause distortion of the valve causing
valve failure. Model RF-DBI-LH Rubber-Flex
Low Head Loss In-Line Duckbill Check Valve

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2.0 Storage and Handling
2.1 Storage
2.1.1 Inside
Figure 8: Typical Check Valve Storage Position
2.1.2 Outside
If the rubber check valve is to be stored outside, keep the check valve protected in a waterproof crate until ready
for installation. Keep the check valve protected from any external elements such as direct UV exposure. Do not
lay other boxes on top of the check valve or check valve box.
2.2 Handling
3.0 Prior to Installation
3.1 Inspect the Received Check Valve
3.2 Verify the System Parameters
Check the system design parameters for the application to ensure the specified/supplied Cla-Val Rubber-Flex Duckbill Check Valve(s)
will meet the system requirements.
3.3 Check Valve Mating Surface
Inspect the mating flange/surface to ensure that it is undamaged and clean and free of all foreign matter before installation of the
check valve. For slip-on style of rubber check valves, the mating pipe must be free of sharp edges which may damage the inside
sealing diameter of the check valve.
3.4 Safety Area
Always check your work area before installation for safety hazards which may cause injury or damage to personnel or product.
Develop and discuss a safety and exit plan for you and your fellow employees in the event of an emergency.
The ideal storage location for a Cla-Val Rubber-Flex Duckbill Check Valve is in a warehouse setting with a
relatively dry and cool location. Store the check valve in a vertical position on a pallet or wooden platform
similar to as shown in Figure 8 below.
Care should be taken when handling the Cla-Val Rubber-Flex Duckbill Check Valves whether big or small to reduce the
possibility of damaging the check valve during installation. For large size check valves, special care should be taken in loading,
hoisting, and lowering; being careful not to hit adjacent equipment, forklift tines, crane cables, etc. Model RF-DBF & RF-DBO
valves 36” and larger are manufactured with a lifting support hole to assist in the safe and proper lifting/installation of these
check valves. The lifting support holes are not intended to support the entire weight of the check valve and care must be taken to
adequately support the cuffed or flanged end as well. Note: Cla-Val will not be responsible or liable for damage to the rubber
check valve, adjacent equipment, or injury to personnel if these steps are not taken.
Rubber-Flex check valves are fully inspected at the factory and are carefully packaged to arrive at the job site ready for
installation. Upon receipt of the check valve(s), inspect for damage that may have occurred during transportation and
immediately contact your transportation company to report any damage. Check the item(s) received against the packing slip to
ensure that all items have been received. For any questions or concerns about the received product contact your Agent or
Cla-Val at [email protected] or for immediate assistance call [phone].

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4.0 Installation
4.1 Rubber-Flex Check Valve Installation
4.1.1 Model RF-DBF: Rubber-Flex Flanged Duckbill Check Valve Installation
4.1.1.1 Step 1: Align
Position/Align the Flanged Rubber check valve into the system. For horizontal applications the bill
of the check valve should be in vertical orientation relative to the ground unless there are clearance
issues. In the case of clearance issues the check valve may be rotated to a maximum of 35 degrees to
allow clearance to the ground.
Figure 9: Model RF-DBF Installation Step 1
4.1.1.2 Step 2: Retaining Rings
Position the split retaining rings onto the flange of the check valve. Use a flat washer to properly
cover the split in the retaining ring.
Figure 10: Model RF-DBF Installation Step 2
4.1.1.3 Step 3: Flange Bolting
Insert the flange bolting and tighten the flange bolting hardware to a “snug” tight fit before
torqueing. Proceed to section 4.1.7 for proper bolt torqueing and a sample torqueing pattern.
Figure 11: Model RF-DBF Installation Step 3
Note: Each Cla-Val Rubber-Flex Check Valve installation can be considered a major pipe installation and the same safety requirements
as used in pipe contracting installations should be implemented. Each Cla-Val Rubber-Flex Check Valve regardless of size should be
installed in the same manner. Cla-Val will accept no responsibility for an improperly installed Rubber-Flex Check Valve(s) or the
improper use of this product. Incorrect installation may result in injury to personnel, reduced check valve service life and/or damage to
other adjacent equipment.

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4.1.2 Model RF-DBI: Rubber-Flex Flanged In-Line Duckbill Check Valve
4.1.2.1 Step 1: Insert
Insert the Slip-In flanged rubber check valve into the existing pipe. For horizontal applications the
bill of the check valve should be installed in a vertical orientation in the mating pipe as shown in
below in Figure 9.
Figure 12: Model RF-DBI Installation Step 1
4.1.2.2 Step 2: Attach
Re-attach the 2 mating pipe flanges.
Figure 13: Model RF-DBI Installation Step 2
4.1.2.3 Step 3: Flange Bolting
Add the flange bolting to the installation and tighten to a “snug” tightfit before torqueing. Proceed
to step 4.1.7 for proper bolt torqueing and a sample torqueing pattern.
Figure 14: Model RF-DBI Installation Step 3
4.1.3 Model RF-DBO: Rubber-Flex Slip-On Duckbill Check Valve Installation
4.1.3.1 Step 1: Slip-On
For Slip-On rubber check valves, slip the rubber check valve over the existing pipe. For horizontal
applications the bill of the check valve must be installed in a vertical orientation relative to the
ground unless there are clearance issues. In the case of clearance issues the check valve may be
rotated to a maximum of 35 degrees to allow clearance to the ground. To ease installation it is
acceptable but not necessary to add soapy water to the exterior of the pipe to facilitate the
installation of the check valve.
Figure 15: Model RF-DBO Installation Step 1

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4.1.3.2 Step 2: External Clamps
Add the external clamps to the slip-on rubber check valve. For nominal diameters less than or equal
to 10” the check valve will be supplied with either T-Bolt or Worm Gear Clamps. For nominal
diameters greater than 10”, the check valve(s) will be supplied with fabricated stainless steel
clamp(s). If the valve are supplied with more than one fabricated stainless steel clamp, then rotate
the additional clamps which will place the clamping section at opposite angles from the first clamp.
This will ensure that even pressure is applied to the valve. Note: The supplied number of clamps will
vary depending on size and application.
Figure 16: Model RF-DBO Installation Step 2
4.1.3.3 Step 3: Tighten Clamps
Tighten the external clamp until the rubber is
compressed by the external clamp and a tight fit
is achieved then proceed to section 4.1.8 for
anchor bolting/pinning to anchor the slip-on
check valve to the mating piping.
4.1.4 Model DBI-IN: Rubber-Flex Slip-In In-Line Duckbill Check Valve Installation
4.1.4.1 Step 1: Slip-In
Insert the slip-in check valve inside the existing pipe. For horizontal applications the bill of the
check valve must be installed in vertical orientation as shown below in Figure 15.
Figure 18: Model RF-DBI-IN Installation Step 1
4.1.4.2 Step 2: Insert Clamp
Insert and the expandable internal clamp into the rubber check valve.
Figure 19: Model RF-DBI-IN Installation Step 2
Figure 17: Model RF-DBO Installation Step 3

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4.1.4.3 Step 3: Expand Clamp
Tighten the expandable internal clamp until the stainless steel portion of the clamp has imbedded
itself into the rubber of the valve. Tighten the lock nut once the internal expandable clamp is in the
proper position and proceed to section 4.1.8 for anchor bolting/pinning to anchor the slip-in check
valve to the mating pipe. When installing multiple internal expandable clamps ensure the clamps are
evenly spaced/ rotated to provide even clamping pressure as well as the internal expandable fasteners
located in a position that minimizes flow interference. Note: This style of check valve installation
relies on external pressure of the internal expandable clamp to ensure that the valve does not move,
care should be taken to ensure proper sealing.
Figure 20: Model RF-DBI-IN Installation Step 3
4.1.5 Model RF-DBJ: Rubber-Flex Jacket Style Duckbill Check Valve Installation
4.1.5.1 Step 1: Align/Insert
Figure 21: Model RF-DBJ Installation Step 1
4.1.5.2 Step 2: Flange Bolting
Secure the Model RF-DBJ assembly to the mating flanges with the appropriate flange bolting hardware.
Follow the procedures in section 4.1.7 for proper flange bolt torqueing.
Figure 22: Model RF-DBJ Installation Step 2
Align/Insert the Model RF-DBJ Assembly into the required breach opening noting the position of
flow and orientation of the valve. The assembly should be installed to where the top notation on the
Model RF-DBJ shroud is in the vertical position as shown in Figure 21. Use a gasket where required,
supplied by others. Note: Ensure the bill of the check valve is in the vertical position when installed.

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4.1.6 Model RF-DBI-LH: Rubber-Flex Low Head Loss In-Line Duckbill Check Valve Installation
4.1.6.1 Slip In Model RF-DBI-LH
4.1.6.1.1 Step 1: Insert Valve
4.1.6.1.2 Step 2: Insert Clamp
Insert the expandable internal clamp(s)
into the rubber check valve in either the
inlet or discharge end depending on
installation orientation and ensuring that
the adjustable bolts are located at the top
of the valve. When installing multiple
internal expandable clamps ensure the
clamps are evenly spaced/ rotated to
provide even clamping pressure as well
as the internal expandable fasteners
located in a position that minimizes flow
interference.
4.1.6.1.3 Step 3: Expand Clamp
Tighten the expandable internal clamp
until the stainless-steel portion of the
clamp has imbedded itself into the rubber
of the valve. Tighten the lock nut once
the internal expandable clamp is in the
proper position and proceed to section
4.1.8 for anchor bolting/pinning to anchor
the slip-in check valve to the mating pipe.
Note: This style of check valve
installation relies on external pressure of
the internal expandable clamp to ensure
that the valve does not move, care should
be taken to ensure proper sealing.
4.1.6.2 Flanged Model RF-DBI-LH
4.1.6.2.1 Step 1: Insert
Figure 23
: Model RF-DBI-LH Installation Step 1
Figure 25: Model RF-DBI-LH Installation Step 3
Figure 26: Model RF-DBI-LH Flanged Installation
Step 1
Figure 24
: Model RF-DBI-LH Installation Step 2
The RF-DBI-LH valve must be installed
in a horizontal pipe and will be supplied
with a “FLOW” direction label and a
“TOP” label to ensure proper installation
orientation within the pipe. Insert the
slip-in check valve inside the existing pipe
and push until inlet/discharge end is flush
with end of pipe.
The RF-DBI-LH valve must be installed
in a horizontal pipe and will be supplied
with a “FLOW” direction label and a
“TOP” label to ensure proper
installation orientation within the pipe.
Insert the slip-in flanged check valve
inside the existing pipe and push until
flanged inlet/discharge end is flush with
end of pipe.
Note: Model RF-DBI-LH Flanged
Check Valve can be supplied with the
integrated rubber flange in the inlet or
discharge position depending on the
required installation parameters.

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4.1.6.2.2 Step 2: Retaining Ring & Bolting Installation
Attach and secure the retaining ring in place with the flange bolting hardware and
proceed to section 4.1.7 for flange bolt torqueing
Figure 27: Model RF-DBI-LH Flanged Installation Step 2
4.1.7 Flange Bolt Torqueing (Model RF-DBF/RF-DBI/RF-DBJ & Flanged RF-DBI-LH)
Torqueing should then be accomplished in steps gradually
and as evenly as possible around the circumference of the
flange. The bolts should be tightened in an alternating
sequence similar to a star pattern shown below in Figure 18
to within the proper torque range specified for the size of
check valve to be installed. The flange bolting is not
considered tight and “locked-on” until the edges of the check
valve flange bulges out or extrudes slightly. Refer to
appendix A for the proper ranges of torque values as well as
further examples of the proper patterns used for torqueing the
flange bolting. Note: Never tighten bolts on a flanged rubber
check valve to the point where there is contact between the
retaining ring and mating flange. This type of tightening will
crush the integrated rubber flange of the check valve and
cause a premature failure.
4.1.8 Anchor Bolts/Pins (Model RF-DBO/RF-DBI-IN/RF-DBI-LH)
After the Check Valve is installed, drill a hole or holes, depending on the valve size number of clamps, through
the cuff of the check valve and into the mating pipe using the center hole on the clamp as a guide. Insert a bolt,
which will be sufficient in length to completely travel through the clamp, valve and mating pipe. Completely
weld or use some other means of ensuring that this bolt/pin will not fall out or be removed.
Figure 29: Model RF-DBO, RF-DBI-IN & RF-DBI-LH Typical Drilled Through Hole Positions
Figure 28: Sample Flange Torqueing
Sequence

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4.1.8.1 Model RF-DBO: Insert the Bolt/Pin through the drilled hole(s) and completely weld or use some other
means of ensuring that this bolt/pin will not fall out or be removed from the expandable clamp.
Figure 30: Model RF-DBO Anchor Bolt/Pin Install
4.1.8.2 Model RF-DBI-IN: Insert the Bolt/Pin through the drilled hole(s) and completely weld or use some other
means of ensuring that this bolt/pin will not fall out or be removed from to the internal expandable clamp.
Figure 31: Model RF-DBI-IN Anchor Bolt/Pin Installation
4.1.8.3 Model RF-DBI-LH: Insert the Bolt/Pin through the drilled hole(s) and completely weld or use some other
means of ensuring that this bolt/pin will not fall out or be removed from to the internal expandable clamp.
Figure 32: Model RF-DBI-LH Anchor Bolt/Pin Installation
5.0 Operation
The Rubber-Flex Duckbill Check Valves require little operational requirements. Each unit is an elastomeric back flow device which relies
solely on inlet flow pressure and back flow pressure to provide operation.
6.0 Maintenance
Rubber-Flex Duckbill Check Valves require little maintenance. Periodic inspections can ensure that the check valve will provide years of
maintenance-free service. Check for cuts or gouges which can easily be repaired with a self-curing rubber compound (Contact Cla-Val).
Ensure that the bill section is free from any debris that may have been lodged in the bill. This will be the only areas of concern that require
periodic inspection.

7.0 Appendix A
7.1 Torque Data
Table 1: Model RF-DBF/RF-DBO/RF-DBJ/RF-DBI-LH
Size Approx. Torque Values
1" thru 2" 20 - 40 ft./lbs.
2.5" thru 5" 25 - 60 ft./lbs.
6" thru 12" 35 - 140 ft./lbs.
14" thru 18" 50 - 180 ft./lbs.
20" thru 24" 60 - 200 ft./lbs.
26" thru 40" 70 - 300 ft./lbs.
42" thru 50" 80 - 300 ft./lbs.
52" thru 60" 100 - 400 ft./lbs.
66" thru 72" 200 - 500 ft./lbs.
78" thru 90" 300 - 600 ft./lbs.
96" thru 108" 400 - 700 ft./lbs.
120" 500 - 800 ft./lbs.
7.2 Sample Torqueing Patterns
Figure 33: Sample Torque Patterns
CLA-VAL
1701 Placentia Ave •Costa Mesa CA 92627 •Phone: [phone] •Fax: [phone] •E-mail: [email protected] •www.cla-val.com
Copyright Cla-Val 2019 • Printed in USA • Specifications subject to change without notice.
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N-Rubber-Flex Duckbill