Method and system for measuring gate valve clearances and seating force
AssigneeLockheed Martin Energy Systems, Inc.
InventorsDonald A. Casada, Howard D. Haynes, John C. Moyers, Brian K. Stewart
Life of this patent
Estimating the term…
Abstract
Valve clearances and seating force, as well as other valve operational parameters, are determined by measuring valve stem rotation during opening and closing operations of a translatable gate valve. The magnitude of the stem rotation, and the relative difference between the stem rotation on opening and closing provides valuable data on the valve internals in a non-intrusive manner.
Claims22
A system for determining operative conditions of a valve having a valve element connected to a threaded valve stem translatable by threaded engagement with a rotatable drive member to move the valve element between open and closed positions, said threaded valve stem being generally constrained from angular movement by engagement with guide means, the system comprising:
- means for measuring absolute rotation of the valve stem during rotation of the rotatable drive member;
- and
- means for correlating the measured absolute valve stem rotation to at least one operative condition of the valve.
A method for determining operative conditions of a valve having a valve element connected to a threaded valve stem translatable by threaded engagement with a rotatable drive member to move the valve element between open and closed positions, said threaded valve stem being generally constrained from angular movement by engagement with guide means, the method comprising the steps of:
- measuring absolute valve stem rotation during rotation of the rotatable drive member;
- and
- correlating the measured valve stem rotation to at least one operative condition of the valve.
A method for determining operative conditions of a valve having a valve element connected to a valve stem, said valve stem being translatable to move the valve element between open and closed positions, the method comprising the steps of:
- measuring valve stem rotation and correlating the measured valve stem rotation to at least one operative condition of the valve;
- and
- measuring linear displacement of the valve stem during opening and closing operations of the valve element by producing a signal indicative of linear displacement of the valve stem, whereby internal clearances of the valve element are determined as a function of measured stem rotation and translation.
Dependencies are inferred from the claim text.