GB862809A - Well servicing rig - Google Patents

Abstract

862,809. Well-rigs. BENDER, E. A. Aug. 10, 1959, No. 27229/59. Class 85. In a truck-mounted wellservicing rig, the mast 48 is pivoted at 66 to members 52, 54 pivoted at 58, 60 to the trunk, the top section 46 of the mast pivoting down, as shown in Fig. 2, to reduce the extent of front projection for the truck, and and the whole being raised to working position by lines and pulleys operated by the drawworks 28. The member 54 is telescopic and is fully extended when the mast is stowed. The mast consists of three tubular members 40, 40, 42 braced by crossstays 44, the member 42 being arranged at the back of the mast and serving as a slide-guide for the end 74 of an elevating arm 68 which is pivoted to a rigid structure 62 and is pulled towards the hinge 66 by a line 168. To erect the mast from the Fig. 2 position, a line 98 passing over a pulley 102 to the drawworks 28 pulls on the end of a toggle lever 80, the lever 80 thus becoming aligned with the other toggle lever 82 to swing the top end of the mast into the dotted line position in which it is locked by a detent on the lever 80 engaging a hole in the lever 82. The line 98 is now removed, and the conventional fast line 126 from the drawworks is passed over one of a pair of pulleys 162 to the crown block assembly 116 and from thence to the travelling block 128, the dead line from which returns to the drawworks over a pulley 118 and the other pulley 162. The block 128 is connected by the line 168 which passes over pulleys 160, 158 with the outer end of the arm 68. Operation of the drawworks will now cause the members 52, 54 to be pivoted upwards, the main hinges 66 being raised above the truck body as the members 54 contract. Further operation causes the arm 68 to slide along and raise the mast about the pivots 66, and when the mast is fully, raised the arm 68 is automatically locked to the rear of the mast and acts as a strut. The mast is lowered by reverse operations which may be intiated by an air cylinder 38 in a line 36 connecting the top of the mast with a rest 32 for the stowed mast. The working loads are taken by the structure 62 and jacks 61, and by outrigger legs 140 connected to the hinges 66 and braced by members 144 hingedly connected to the rear of the truck. Additional braces 147 adjustable in length, are connected at 149 to the sides of the truck. Jacks 148 are arranged between supporting pads 150 and the legs 140. A hinged racking platform 130 is supported on brackets 132 and is arranged to deal with a stand of pipe in "doubles".