Patent ID: 9644447
Date: 2017-05-09
CPC Classifications: E21B,F16J

Claim:
1. Wireline pressure control apparatus for use in an oil or gas well, comprising a grease injector having first and second tubes arranged co-axially and having a bore for passage of the wireline through the tubes and into the well, and a grease injection channel in communication with the bore of the tubes for injecting grease into the bore between the outer surface of the wireline and the inner surface of the bore when the wireline is disposed in the tubes; wherein the tubes are arranged end to end, wherein the bore in each tube is sealed to the bore in at least one adjacent tube, providing a continuous sealed bore extending between the tubes, and wherein each tube has at least one respective radial passage, the bore having a plurality of radial passages through the tubes, at spaced apart locations along the bore, the radial passages being in fluid communication with the bore and providing a leak path for fluids between the inner surface of the bore and the outer surface of the tubes, thereby allowing pressure to equalise between the bore and the outside of the tubes at the spaced locations of the radial passages; and wherein the radial passages are in fluid communication with one another outwith the bore.