GB813183A - Drill pipe non-return valve - Google Patents

Abstract

813,183. Valves. BAKER OIL TOOLS Inc. March 16, 1956. No. 8347/56. Class 135. A non-return valve A, Fig. 1, is located in a section 10 of a drill pipe B between a drill bit C and a section 17 and comprises a cage 19 having upper and lower cylindrical portions 20, 21 interconnected by two longitudinal bars 22. The cylindrical portion 20 has two annular grooves 25 which receive oppositely directed sealing rings 23. The inside lower end of the part 20 has a frusto-conical valve seat 28, Fig. 2, which co-operates with the surface 29 of the valve closure member 30 secured, e.g. by casting, to the valve stem 31 which extends downwardly through a guide 34 located in the bore of a hub 35 of a spider 36 the two radial arms 37 of which extend from the bars 22. The guide 34 is secured with the flange 38 on top of the hub 35 by a nut 39. A non-metallic disc 40 is held against the underside of the closure member 30 by a retaining disc 45 and is provided with a lip 42 which in the closed position of the valve, Fig. 1, engages a seat 43 extending from the seat 28, the retaining disc 45 being acted on by a spring 46 located between the disc 45 and the flange 38. For ease of assembly the hub 35 has a longitudinal slot 48. In the closed position with the closure member 30 against the seat 28 and the lip 42 against the seat 43 fluid is prevented from passing up through the bore of the pipe section 10. The closure members 30, 40 are moved downwardly against the pressure of the spring 46 away from their seats 28, 43 if fluid is pumped down through the bore.