PLASTIC VALVES FOR USE IN

Brand	Owner	Address	Description
POLY PLUG	KEROTEST MANUFACTURING CORP.	5500 Second Avenue Pittsburgh PA 15207	PLASTIC VALVES FOR USE IN NATURAL GAS DISTRIBUTION LINES;
	Where the owner name is not linked, that owner no longer owns the brand

Technical Examples

A method of isolating a reservoir of production fluid in a formation comprises providing a pair of valves (14, 16) in a bore intersecting a production formation and in which the hydrostatic pressuer in the bore at the formation is normally lower than the formation pressure, and then ontrolling the valves (14, 16) from surface such that the valves (14, 16) will only move from a closed configuration to an open configuration on experiencing a predetermined differential pressure across the valves.