TITLE:
NO.:
KEROTEST MODEL-1
REV.: 10
GATE VALVE
DATE: 7/12/07
OPERATIONS MANUAL
PAGE: 9 OF 35
This report is the property of Kerotest Manufacturing Corp. 5500 Second Avenue, Pittsburgh, PA 15207 and may not be
copied by any means without the expressed written consent of Kerotest. It is intended for the sole purpose of helping
Kerotest customers evaluate Kerotest products and may not be released to any third party or otherwise used in any
manner injurious to the interests of Kerotest
.
TROUBLE SHOOTING
VALVE SHUT-OFF
Throttling Valve
If valves are in the open position in a pipeline for a period of time, there is a chance that
sediment or dirt may collect inside the valve. When these valves are to be closed, it should be
done slowly. The valve should not be closed completely by "throttled" slowly. The valve
should not be closed completely but "throttled" for a short time in order that the turbulence
created will flush away any sediment or dirt that might have settled in the valve.
In the event of an emergency, the above method need not be followed, as the valve should be
closed as quickly as possible.
Body and Wedge Seating
When complete shut-off is not obtained, the valve can be reseated in the following manner.
Drive wedge into seats with moderate effort, turn back one (1) or two (2) complete turns
and again drive into seats with moderate effort. Continue this procedure until shut-off is
obtained.
Repacking Valve
Possible causes for a malfunction of the packing seal could be worn packing or utilizing valve
outside of packing temperature limitations.
Temperature limits of valve packing are -30°F to 200°F
Repack valve as described in the "Primary Repacking Procedure", "Secondary
Repacking Procedure", or "Zero Pressure Repacking Procedure" (as applicable) which
follow both Early Design Valves and Late Design Valves with stem weather seal.
