GB832836A - Tubular pipe testing machine - Google Patents

Abstract

832,836. Testing strength of pipes. PHOENIX STEEL CORPORATION [formerly PHOENIX IRON & STEEL CO.]. Aug. 23, 1957 [Aug. 23, 1956], No. 26636/57. Class 106 (2). [Also in Group XXX] A machine for testing the wall strength of pipes comprises a pair of laterally spaced heads with sealing means 10, 11 adapted to engage and seal the ends of a length of pipe 12 by axial pressure on opposite ends of the pipe, means for supplying fluid into the interior of the length of pipe and a follow-up piston 92 actuated by a separate fluid supply for urging the sealing means of the head 10 against the end of the pipe so that it follows any axial shortening of the pipe and preserves a fluidtight seal. The head 10 comprises a block l0a axially bored to accommodate the piston 92 attached to a shaft 38 supporting the sealing structure 10b. Fluid is introduced into the cylinder 87 through the supply line 99 to move the sealing means into engagement with the end of the pipe and pressure is maintained on the piston 92 during the testing by admitting fluid under constant pressure from pipe 100. The pipe 12 is filled from low-pressure pipe 118, check valve 117, conduit 114, chamber 113, passages 111, 112 in shaft 38 and opening 110 in the sealing receptacle 108. As the pipe fills air is forced out of the pipe through opening 121, passages 122, 123 and 124, chamber 125, passage 126, pipe 127, valve 128 and exhaust pipe 129. The valve 128 may be of the type which automatically closes when the air is displaced and water passes through the outlet. At this stage, or somewhat earlier, the rapid filling of the pipe through line 116 is discontinued and pressure is increased in the pipe by introducing fluid under pressure from pipe 119. The sealing receptacle which may be of cup-like form, is secured in an annular bracket 105 by set-screws 109 and has an O-ring 133 which is compressed to effect the seal between the end of the pipe and the receptacle. An alternative form of sealing structure is described wherein a plate having a plurality of concentric annular grooves is introduced between the sealing receptacle and the support 37 to provide alternative positions for the 0-ring 132, dependent upon the diameter of pipe to be tested and its corresponding sealing receptacle. The end of the pipe may be bevelled in which case an adapter with a mating bevelled edge may be fitted in the sealing receptacle. Heads 10 and 11 may be mounted on casters for travel on tracks 14, 15 and pins 21 may be provided to locate the heads in the desired position. Mechanical means comprising a motor 26, gear system 28, rack 24 and pinion 25 may be provided to move the head 11 along the track and air cylinders 23 may operate the pins 21. The sealing means may be moved with relation to the head 11 by a motor 36 driving gearing 35 and nut-like structure 33a meshing with the threaded shaft 32. The pipe 12 rests on inserts 42 of supports 41 spaced at intervals between the heads and is held by overlying pads 43 on hydraulically actuated arms 44. Rollers 50, rotated by motors 53, move the pipe axially to a position in line with the sealing receptacles and shaped ends of hydraulically-actuated arms 55 lift and deliver the pipe to the inserts 42.