GB956191A - Wellhead assemblies - Google Patents

Abstract

956,191. Wells. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. May 8, 1962 [May 10, 1961], No. 17654/62. Heading E1F. A wellhead assembly comprises a member 21 having a vertical conduit 22, a conduit 24 branching from the conduit 22, a closure member 34 in the conduit 22, enlargement 43 in the conduit 22 for the reception of the latch means 44 of the closure member, a fishing neck 70 formed on the top of the operating means 60, 63 of the latch means for removing the closure member, and guide means 52 on the conduit 22 for co-operation with guide means 54 of the closure member to ensure that the closure member is latched to the conduit 22 with the lower surface 37 of the closure member registering with the curved inner wall of the conduit 24. The closure member rests on a seat and has packing 50 which engages a reduced portion 51 of the conduit 22. The balls 44 are held and urged outwardly by the sleeve 60 which is pulled downwardly by the spring 63. The sleeve is held in the operative position by latches 64 which are unlatched to permit removal of the closure member by a pin on the fishing tool (not shown) entering a bore 68. The guide 52 co-operates with the lower surface of a series of collet fingers 54 which are collapsed by a shoulder 58 during removal of the closure member. In a modification a single spring finger depending from the closure member engages the lower part of a cam formed on the internal surface of the conduit 22. Specification 924,903 is referred to