Val-Matic Tilted Disc Check Valve User Manual
Manual No.
TDCV-OM1-4
Val-Matic®
®
Tilted Disc
Check Valve
Operation, Maintenance and
Installation Manual
INTRODUCTION ............................................... 1
RECEIVING AND STORAGE ........................... 1
DESCRIPTION OF OPERATION ...................... 1
INSTALLATION ................................................ 2
VALVE CONSTRUCTION ................................. 3
MAINTENANCE ................................................ 4
TROUBLESHOOTING ...................................... 4
DISASSEMBLY ................................................. 5
REASSEMBLY .................................................. 5
OPTIONAL BMOD ............................................ 8
OPTIONAL TMOD ............................................ 11
OPTIONAL BYPASS ......................................... 15
PARTS AND SERVICE ..................................... 15
WARRANTY ..................................................... 16
VAL-MATIC
905 Riverside Dr. ● Elmhurst, IL 60126
Phone (630) 941-7600 ● Fax (630) 941-8042
www.valmatic.com
®
VALVE AND MANUFACTURING CORP.
TILTED DISC® CHECK VALVE
OPERATION, MAINTENANCE AND INSTALLATION
INTRODUCTION
This manual will provide you with the information to
properly install and maintain the check valve to
ensure a long service life. The Tilted Disc Check
Valve is ruggedly constructed with aluminum-bronze
or stainless steel trim to give years of trouble free
operation. The valve should be installed in water
pipelines three diameters downstream of pumps to
prevent reverse flow.
For valves with Top Mounted Dashpots, DO
NOT paint exposed surfaces of the
connecting rod or the cylinder piston rod or
damage will result to the hydraulic seals.
The valve is designed to open after pump start and
allow water to flow through the pipeline or water
main while creating a minimal amount of headloss.
A top or bottom mounted oil dashpot may be
included to control the opening and closing of the
valve. The valve size, cold working pressure, and
model number are stamped on the nameplate for
reference.
This valve is not intended for fluids containing
suspended solids such as wastewater. For
wastewater and other high turbidity applications, use
Val-Matic Series 500 Swing-Flex
The Tilted Disc Check Valve is not intended
for use with sewage or fuel service.
RECEIVING AND STORAGE
Inspect valves upon receipt for damage in shipment.
Unload all valves carefully to the ground without
dropping. When lifting, the valve should be lifted
with straps or bolts in the flange holes. The valve
should never be lifted by the dashpot assembly.
The valves should remain crated, clean and dry until
installed to prevent weather related damage. For
long-term storage greater than six months, the
valves should be stored indoors or the ends of the
valve should be sealed with plastic wrap to prevent
weather related damage.
CAUTION
CAUTION
Check Valve.
FIGURE 1. Tilted Disc
Check Valve
DESCRIPTION OF OPERATION
The Tilted Disc Check Valve consists of two body
sections bolted together at a central 55-degree
diagonal flange assembly, forming a single valve
body. The inlet body section contains a seat ring
positioned and captured by the diagonal flanges.
The outlet section contains two eccentrically located
pivot pins from which a disc, containing a beveled
disc ring, pivots 40 degrees from the closed to the
fully open position.
The location of the eccentric pivot trunnions allows
the seating surface of the disc ring to rotate away
from the seating surface of the seat ring, without
contact, when the valve opens. Conversely, during
closing the seating surface of the disc ring moves
into the seating surface of the seat ring without
contact, until final sealing contact is made. A small
amount of clearance exists between the pivot pin
and the pivot pin bushing when the disc ring makes
full contact with the seat ring to ensure a tight seal.
The flow area throughout the valve equals or
exceeds the flow area of the pipe, thus minimizing
the head loss through the valve.
1
DESCRIPTION OF OPERATION (cont’d)
p
Upon pump start-up, the forward flow of water will
start to rotate the disc about the pivot pins until the
disc rotates through a 40-degree arc and contacts
the integral body stops. The partially balanced disc
assists in opening the disc and stabilizes the disc in
low-flow cases where the valve remains partially
open.
On pump shutdown, the forward velocity of the water
starts to diminish, until the disc is no longer held
against the body stops and the partially balanced
disc will move to the closed position. When the
forward velocity reaches zero, the disc will have
moved to the closed position and the reversal of flow
is checked. The 40-degree travel of the disc and the
partially balanced disc reduces the potential for
check valve slam and water hammer normally
associated with conventional swing check valves.
However, ideal hydraulic conditions are not always
predictable and the potential for water hammer can
still exist. Applications with a potential for valve slam
include high-head pumping, multiple high service
pumps, and the use of hydro-pneumatic surge tanks.
If the reversal of flow occurs before the disc has a
chance to fully close, it will be driven to the closed
position by the rapid flow reversal.
For these rapid flow reversal conditions, a bottom
mounted hydraulic dashpot can be fitted in the
bottom inspection port, provided that sufficient
clearance is provided for installation. The bottom
mounted oil dashpot will control the last 10 degrees
of disc travel between 1 and 5 seconds. A top
mounted dashpot can also be used. A top mounted
oil dashpot performs the same function as a bottom
dashpot and in addition, independently controls the
full open and closing strokes between 5 and 30
seconds to prevent line surges.
INSTALLATION
The installation of the valve is important for its
proper operation. The Tilted Disc Check Valve can
only be used for horizontal flow or vertical flow-up
applications.
For horizontal flow applications, the valve must
be installed with both of the eccentric pivot pin
trunnions located above the horizontal
centerline of the valve and they must be level
to the horizontal
Each valve is provided with a flow arrow integrally
cast on the valve body and a flow arrow printed on
the metal label attached to the valve. These flow
arrows must point in the direction the water will flow,
when the system is operating. ANSI Class 125 and
Class 250 Cast Iron valves are furnished with flat
CAUTION
lane of the valve.
faced flanges and should be mated with flat faced
companion flanges. The valve and adjacent piping
must be supported and aligned to prevent
cantilevered stress being transferred to the valve’s
flanges when installing the flange bolts or studs. For
raised face applications, a ductile iron valve body
should be specified.
CAUTION
The valve must be mated with flat-faced
flanges or damage may result. The use of
excessive bolt torque can damage the valve.
When mating the check valve with butterfly isolation
valves, the clearance between the butterfly disc and
the fully open check valve stem must be checked. A
spacer pipe is sometimes needed. See the valve
arrangement drawing for disc clearance dimensions.
FLANGED ENDS: The flange should be mated with
flat-faced pipe flanges equipped with resilient
gaskets. When ring gaskets are used, the bolt
material shall be ASTM A307 Grade B or SAE
Grade 2 Carbon Steel. Higher strength bolts should
only be used with full-face gaskets.
INSTALLATION: Lower valve into the pipeline using
slings or chains around the valve body. Eye bolts or
bars can also be used in the bolt holes. Lubricate
the flange bolts and insert them around the flange.
Lightly turn bolts until gaps are eliminated. The
tightening of the bolts should then be done in
graduated steps using the cross-over tightening
method. Recommended lubricated torques for use
with resilient gaskets (75 durometer) is given in
Table 1. Do not exceed bolt rating or crush gasket
more than 50 percent of its thickness.
125# FLANGE DATA 250# FLANGE DATA
Valve
Size
(in)
4 5/8 30-90 4 3/4 50-150
6 3/4 30-90 6 3/4 70-150
8 3/4 40-120 8 7/8 90-200
10 7/8 45-150 10 1 110-300
12 7/8 65-200 12 1 1/8 160-450
14 1 80-250 14 1 1/8 140-450
16 1 90-300 16 1 1/4 180-600
18 1 1/8 100-350 18 1 1/4 190-600
20 1 1/8 120-450 20 1 1/4 220-600
24 1 1/4 150-500 24 1 1/2 350-900
30 1 1/4 180-600 30 1 3/4 500-1500
36 1 1/2 250-750 36 2 700-2000
42 1 1/2 300-900 42 2 800-2500
48 1 1/2 400-900 48 2 900-1800
54 1 3/4 400-1200 - - -
Bolt
Dia.
(in)
Bolt
Torque
(ft-lbs)
Valve
Size
(in)
Bolt
Dia.
(in)
Bolt
Torque
(ft-lbs)
TABLE 1. Flange Bolt Torques
2
VALVE CONSTRUCTION
The standard Tilted Disc Check valve is ruggedly
constructed of cast iron. See the specific Materials
List submitted for the order if other than standard
iron construction. The internal metal components
are aluminum bronze or stainless steel. The pivot
pins (4) are fixed in the body (1) and support the
disc (3). Grease fittings (23) are provided to allow
regular lubrication of the pivot pin. The general
details of construction are illustrated in Figure 2.
The body is flanged to connect to a pipe flange. The
body consists of a pivot body half (1) and a seat
pivot half (2). The seat (11) is held in place by the
two body halves. Top and bottom inspection hole
covers (13) are provided for servicing the valves and
to allow installation of dashpots. Do not remove the
inspection covers while the pipeline is under
pressure or the cover may release pressure
suddenly.
Removal of inspection covers without draining
the pipeline and valve may cause serious
injury.
WARNING
Figure 2. Basic Valve Construction
Part No. Part Name Material Part No. Part Name Material
1 Pivot Body Half Cast or Ductile Iron 16 Pivot Pin Cover Cast Iron
2 Seat Body Half Cast or Ductile Iron 17* Pivot Pin Cover Gasket Non-Asbestos
3 Disc Cast or Ductile Iron 18 Pivot Pin Cover Bolt Alloy Steel
4* Pivot Pin Alum. Brz. 19 Indicator Pin (>6”) Stainless Steel
5* Pivot Pin Bushing (>12”) Alum. Brz. 20 Indicator Shaft Assy (>6”) Stainless Steel
6* Body Seal Buna-N 21 Indicator Washer (>6”) Stainless Steel
7 Body Flange Bolt Alloy Steel 22 Indicator Pointer (>6”) Carbon Steel
8 Disc Ring (>12”) Alum. Brz. 23* Grease Fitting Stainless Steel
9 Ring Seal (>12”) Buna-N 24* Indicator O-rings (>6”) Buna-N
10 Seat Ring Alum. Brz. 25 Lock Washer (>6”) Stainless Steel
11 Seat Ring Seal Buna-N 26 Indicator Jam Nut (>6”) Stainless Steel
12 Ring Ret. Screw (>12”) Stainless Steel 27 Locating Pins Plated Steel
13 Inspection Cover (>6”) Cast Iron
14 Cover Bolt (>6”) Alloy Steel
15* Gasket (>6”) Non-Asbestos
*Recommended Spare Part
3
MAINTENANCE
The operation of the valve can be seen by observing
the movement of the indicator pointer on the side of
the valve (6” and larger sizes). The valve should
move about 40 degrees from the closed to the fully
open position. It is normal for the valve to not fully
open in cases where the fluid velocity is less than 8
ft/sec or a Top Mounted Oil Dashpot is installed.
Dashpot assemblies require regular maintenance.
See the dashpot section in this manual.
LUBRICATION: The Tilted Disc Check Valve is
provided with grease fittings (23) located on the
pivot pin covers. The valve’s pivot trunnions must
be lubricated at least monthly or as conditions
dictate with a waterproof, FDA or ANSI/NSF 61
approved grease such as Lubriko #CW-606 (Master
Lubricants Co., Philadelphia, Pa). Using a cartridge
grease gun, pump grease into each grease fitting
using 8 full strokes of the grease gun lever.
INSPECTION: Periodic inspection for leakage can
be performed by placing a listening device or an ear
on the valve while it is closed and the line is under
pressure. If leakage is heard, close the isolation
valve and drain the valve connection, and inspect
the seating surfaces for wear or mineral deposits.
Clean or repair trim as needed.
Removal of inspection covers without draining
the pipeline and valve may cause serious
injury.
The inspection hole covers can be removed from the
valve to facilitate internal inspection of the valve. A
hoist or jacking mechanism should be used to lift the
disc to inspect the seating surfaces. If replacement
of the disc, pivot pin bushings, disc ring, or seat ring
is required, the valve must first be removed from the
line.
WARNING
TROUBLESHOOTING
Several problems and solutions are presented below
to assist you in trouble shooting the valve assembly
in an efficient manner.
TROUBLESHOOTING BASIC VALVE: The valve
opens automatically without the need of a power
source to allow forward flow. The valve may not
open to the full open position depending on fluid
velocity but it will always open far enough to pass
the flow with a minimal headloss. The valve will
automatically close to prevent reverse flow through
the pump. The valve has metal seats and a
moderate bang during closing is normal.
1. Leakage at Valve Inspection Covers (13): Retighten bolts evenly or replace non-asbestos
sheet gasket.
2. Leakage at Grease fitting: Inject grease or
replace grease fitting (23).
3. Leakage at Mating Flanges: Re-tighten bolts
using the cross-over method or replace mating
flange gasket. Flange gaskets are typically 70
durometer resilient material. Check alignment
of mating pipe.
4. Valve Leaks when Closed: Flush debris from
seat by cycling valve. Verify that valve is subject
to a minimum differential pressure of at least 10
psi when closed and the isolation butterfly or
gate valve is open. If leakage persists, inspect
interior of valve. Clean seating surfaces. When
used with a power operated control valve, there
may not be sufficient reverse flow to seat the
valve. These types of installations require a
power outage for proper valve seating so that
the pump is tripped while the control valve is
open.
5. Valve Fails to Open: Check pressure differential
across disc; upstream pressure must be greater
than downstream pressure. Verify that the
suction and discharge shutoff valves are open
and there is no line blockage. Drain pipe on
both sides of the valve, remove inspection cover
(13), and inspect disc ring (8) and seat ring (10)
for damage or wedged debris.
6. Noisy Operation: Flow noise is normal. Loud
flow noise similar to hammering may be
cavitation from dropping high pressures across
valve; review flow velocity through valve and
pump application.
4
DISASSEMBLY OF BASIC VALVE
The valve should be removed from the pipeline for
disassembly. All work on the valve should be
performed by a skilled mechanic with proper tools.
Refer to Figure 2.
The line must be drained before removing the
valve or pressure may be released causing
injury.
WARNING
1. Lay valve on flat surface or bench with the inlet
flange face down.
2. Using a flat-nosed punch, drive out the two
locating pins (27).
3. Remove the indicator jam nut (26), lockwasher
(25), pointer (22), pivot pin cover bolts (18) and
covers (16).
4. Remove the pivot pins (4). The end of the pin is
tapped for insertion of a 9/16”-18 or 3/4”-16
threaded rod.
5. Attach a hoist to the outer flange of the valve to
support the weight of the outlet body section of
the valve and remove the diagonal flange bolts
(7).
6. Using the hoist, raise the outlet body section of
the valve. If the valve sections are joined tightly
by the gasket, lift the valve 1/8” and hammer the
inlet body section down with a soft-blow hammer
or block of wood. Once the body sections are
separated, raise the outlet section to clear the
disc pivot trunnions and place the outlet section
on a wooden skid.
7. Remove the pivot pin bushings (5) from the disc
pivot trunnions on 12” and larger valves. They
may be set in place with sealant so apply heat to
the disc trunnions with a propane torch to soften
the Loctite if necessary.
8. Thread an eye bolt into one of the threaded holes
in the disc’s rectangular pad. Using a nylon sling
through the disc trunnions and eye bolt, lift the
disc straight up while maintaining its 55 degree
tilt.
9. Place the disc on a wooden skid and using the
nylon sling through just the eye bolt, turn the disc
over with the disc ring (8) facing up.
All parts can now be easily inspected for wear or
damage and replacement parts can be ordered as
needed. If replacing the seat (10) or disc ring (8), it
is recommended that they be replaced as a set. The
pivot pins (4) should fit tightly in the body, but there
should be ample clearance (at least 1/32”) between
the pins (4) and the bushings (5).
REASSEMBLY OF BASIC VALVE
All parts must be clean and gasket surfaces should
be cleaned with a stiff wire brush in the direction of
the serrations or machine marks. Worn parts,
gaskets, and seals should be replaced during
reassembly.
1. Place the seat body half (2), with the inlet flange
face down on a wooden skid.
2. Install a lightly lubricated seat ring seal (11) in the
register of the seat body half.
3. Install the seat ring (10) with the serrated surface
toward the seal, into the register of the body seat
half.
4. With the disc on a wooden skid, and the disc ring
register up, place a lightly lubricated disc ring
seal (9) onto the disc register.
5. Assemble the disc ring with the serrated face
toward the seal.
6. Place a small amount of Loctite thread locking
compound on each of the retaining screws (12)
and thread them into the tapped holes in the disc.
Tighten them initially hand tight and then using
the cross-over tightening method, torque each
screw in graduated steps, according to the
following chart.
Valve Sizes Torque
12” to 14” 13 ft-lbs
16” to 24” 20 ft-lbs
30” 28 ft-lbs
36” and larger 40 ft-lbs
7. Thread in eye bolt into one of the threaded holes
in the disc’s rectangular pad. Insert a nylon sling
through the eye bolt and attach the loops of the
sling to the hook of a hoist. Carefully turn over
the disc, using the hoist, making sure that the
beveled seating surface of the disc ring does not
make contact with metal or hard surfaces.
8. Install the pivot pin bushings into the disc pivot
trunnions with Loctite 680.
9. Remove the nylon sling from the eye bolt and
place it through the disc’s pivot trunnions bores
and attach the loops of the sling to the hoist.
Attach a short chain from the hoist’s hook to the
eyebolt and adjust the length of the chain to keep
the disc at a 55 degree angle when housing the
disc.
5
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