GB860914A - Tubing hanger assembly - Google Patents

Abstract

860,914. Oil wells. OIL CENTER TOOL CO. Nov. 27,1959 (Aug. 19,1959], no: 40362/59. Class 85. A tubing hanger assembly, more particularly for use in an underwater well installation where it may be manipulated, for locking and unlocking, without the services of a diver, comprises a tubular hangersupport locked within a casing head, a tubing hanger attached to the upper end of the tubing string, and means for releasably locking the hanger within the support. In Fig. 4, the tubular hanger-support 12 is slidably received in the casing head 16, a sleeve 20, spaced from the skirt 18 of the support 12 to accommodate an annular cam 46, being secured, with intervening packing 24, by screws 32 to the support 12. When the support 12 is lowered into the casing head 16, locking dogs 42 are held radially retracted by shear pins 45, the cam 46 being beneath the dogs and the abutment ring 56 for the springs 52 being anchored by shear pins 58. When the ring 56 lands on the shoulder 170, the pins 58 are sheared and the ring is moved up to the position shown in Fig. 4 in which it is held by spring-pressed slips 59. The upward force thrusts the cam face 48 past the dogs, shears the pins 45 and moves the dogs into circumferentially spaced locking recesses 40. The hanger-support 12 has cylindrical bore portions 60, 62, 64, 66, 68 of diameters decreasing downwardly, the cylindrical parts being joined by tapers 70, 72, 74, 76. A seal carrier 80, with seal 92, is insertable in the support 12, being positioned by radial lugs 84 which engage J-slots 86 in the cylindrical wall part 66, the seal carrier being manipulated by a removable tool which engages J-slots 88 in the inner wall of the carrier. The tubing string 152 is wiped by the seal 92 as it is lowered therethrough, the string being attached to a sub 150 which is attached to a tubing hanger 100. The hanger 100 lands on the tapers 70, 72, locking lugs 120 then being forced into an annular groove 122 in the support 12 by springs 128. If it is necessary to raise the tubing string, a back pressure valve is installed in the locking groove 156 of the sub 150, and a pump-through type back pressure valve is installed in the locking groove 158 of a slide valve 146 held against axial movement in the bore 142 of the tubing hanger 100 by a shear pin 149. The upper back pressure valve is then picked up, in known manner, to shear the pin 149 and to lift the valve 146 to admit pressure pumped to the space between the back pressure valves to a passage 144 leading to the back of a piston 123 on each locking lug 120. The lugs are thus withdrawn against the force of the springs 128 and the hanger 100 is withdrawable, with the sub and tubing-string, from the support 12. In a modification, the fluid-actuated lugs 120 are replaced by lugs fixed radially on the hanger 100, the lugs engaging J-slots in the support 12. A well tool is engaged with the upper end of the hanger 100 for manipulating the hanger in, or out of, the J-slots.