(1) Field of the Invention
This invention relates to cleaning valves in fluid handling systems and more particularly to an independently actuated reciprocating rod.
(2) Description of the Prior Art
Flow transmitters and flow measuring devices are often connected by valves to process pipes. Foreign matter and debris periodically block the duct connecting these valves to the conduit. This debris could be a waxy substance: tars, coke, pulp, powders from slurries, etc. My U.S. Pat. No. 4,192,342 shows the telescoping of a cleaning rod within a hollow stem and forcing the rod through the duct to clean debris. That patent discloses a permanent cleaning rod to be used in every duct which requires cleaning. This is expensive in large process plants. In addition the telescoped rod may be unexpectedly unscrewed, allowing the loss of the fore end of the tool and consequent release of process fluid when the remaining rod-out tool is withdrawn.