Flowserve Valtek Tek-Check Installation, Operation & Maintenance Instructions page 4

Troubleshooting
If difficulty is suspected with the non-slam piston check
valve, do the following:
1. Check for the proper full-stroke operation as indi-
cated in 'Quick-check' section.
2. Check for leaks through the gaskets. The gaskets
should be replaced whenever the valve is disas-
sembled.
3. The seat ring may be out of alignment with the piston.
Check step 8 in 'Reassembly' section on page 3 for
proper procedure on aligning the seat ring and piston.
4. Make sure the valve is properly installed in the line
with correct flow direction.
5. If the piston sticks, disassemble the valve and clean
thoroughly.
GENERAL MAINTENANCE ON PISTON
CHECK VALVES
Disassembly
To disassemble the piston check valve, refer to Figure 2
and proceed as follows:
1. Remove body bolting and lift bonnet cap out of valve.
2. Lift spring, piston, retainer, gaskets, and seat ring out
of the body. Check for signs of galling and scoring
between piston and retainer. If galling exists, call your
Flowserve representative, or the factory.
Flowserve Corporation has established industry leadership in the design and manufacture of its products. When properly selected, this Flowserve product is designed to perform its
intended function safely during its useful life. However, the purchaser or user of Flowserve products should be aware that Flowserve products might be used in numerous applications
under a wide variety of industrial service conditions. Although Flowserve can (and often does) provide general guidelines, it cannot provide specific data and warnings for all possible
applications. The purchaser/user must therefore assume the ultimate responsibility for the proper sizing and selection, installation, operation and maintenance of Flowserve products.
The purchaser/user should read and understand the Installation Operation Maintenance (IOM) instructions included with the product, and train its employees and contractors in the safe
use of Flowserve products in connection with the specific application.
While the information and specifications presented in this literature are believed to be accurate, they are supplied for informative purposes only and should not be considered certified or
as a guarantee of satisfactory results by reliance thereon. Nothing contained herein is to be construed as a warranty or guarantee, express or implied, regarding any matter with respect
to this product. Because Flowserve is continually improving and upgrading its product design, the specifications, dimensions and information contained herein are subject to change
without notice. Should any question arise concerning these provisions, the purchaser/user should contact Flowserve Corporation at any of its worldwide operations or offices.
For more information, contact:
Flowserve and Valtek are registered trademarks of Flowserve Corporation.
19-4
FCD VLAIM019-05 ©2000 Flowserve Corporation. Flowserve Corporation, Valtek Control Products, Tel. USA 801 489 8611
3. Check the piston's vent passages for dirt buildup and
other obstacles. Clean with appropriate industrial
solvent if necessary.
4. Check seat ring and piston seating areas for damage.
If remachining is attempted, care must be taken to
match the original plug surface contour. The seat ring
seating area can be remachined to a 33 degree
angle; the plug angle is 30 degrees. Remachine
surfaces of both parts if required.
Reassembly
To reassemble the piston check valve, refer to Figure 2
and proceed as follows:
1. Replace the seat ring gasket.
NOTE: Gaskets should be replaced each time disas-
sembly takes place.
2. Insert seat ring.
3. Install the retainer and piston.
4. Position the spring in top of the piston.
5. Replace bonnet gasket and bonnet cap.
6. Tighten one bonnet
1
/ of a turn. Proceed until all bolts are tightened
6
evenly and completely, seating the bonnet metal-to-
metal in the body. The bottoming of the bonnet cap in
the body can be easily felt through the wrench.
CAUTION: Insufficient tightening of the bolting
causes poor gasket compression and can result
in leakage.
For more information about Flowserve, contact www.flowserve.com or call USA 972 443 6500
Regional Headquarters 12, av. du Québec, B.P. 645
91965, Courtaboeuf Cedex,
1350 N. Mt. Springs Prkwy.
France
Springville, UT 84663 Phone (33 1) 60 92 32 51
Phone 801 489 8611 Facsimile (33 1) 60 92 32 99
Facsimile 801 489 3719
Quick Response Centers
12 Tuas Avenue 20
Republic of Signapore 638824
5114 Railroad Street
Phone (65) 862 3332 Deer Park, TX 77536 USA
Facsimile (65) 862 4940
Phone 281 479 9500
Facsimile 281 479 8511
1 / of a turn. Tighten opposite bolt
6
104 Chelsea Parkway
Boothwyn, PA 19061 USA
Phone 610 497 8600
Facsimile 610 497 6680
1300 Parkway View Drive
Pittsburgh, PA 15205 USA
Phone 412 787 8803
Facsimile 412 787 1944