Date: December 8, 1999
To: ALL BOILER INSTALLERS, CONTRACTORS, OWNERS, SUPPLIERS, MANUFACTURERS, INSPECTORS, AND PURCHASING AGENTS
From: ANDY SLIMP, ACTING CHIEF BOILER INSPECTOR
Re: UPDATE: ITT GENERAL CONTROLS HYDRAMOTOR GAS "V710" VALVES WITH AN OVERTRAVEL SEAL
Further analysis of the ITT General Controls V710 valves identified in the Oklahoma Department of Labor November 17, 1999, memo points to the overtravel seal as the potential problem. The overtravel seal might deteriorate, allowing gas to leak through the closed valve. Four ITT V710 valves with deteriorated overtravel seals were reported this week to ODOL.
Pressure testing has proven to be an inaccurate means by which to determine the integrity of the overtravel seal. ODOL strongly recommends that a visual, internal inspection be conducted immediately on all ITT V710 valves with an overtravel seal to determine the condition of the seal. It is further recommended that a visual, internal inspection be conducted on V710 valves which are not immediately identifiable as having the overtravel seal.
The seal can be viewed by removing the inlet piping and cycling the valve to an open position. Contact a firm licensed with ODOL to repair or service boilers to conduct this inspection.
The integrity of the overtravel seal must be confirmed before any boiler with a V710 valve manufactured prior to 1989 is operated further.
NOTE: This memo is not intended to suggest the potential problem only exists with the valves identified above. Similar, older model, valves from other manufacturer's should also be examined to determine the integrity of the overtravel seal. Annual maintenance should always be performed on all valves.
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This page was last edited on: January 16, 2007