| 摘要 |
An apparatus for making up or breaking out of two members having mating threaded connections, such as pipe joints or bolts for avoiding undesirable transverse forces relative to the two members during tightening (or loosening), thereby insuring the connection is made up (or broken out) by essentially pure torque loads. The apparatus includes a power-driven lead tong, a back-up tong, a load cell which cooperates with either tong to produce a torque measurement and an interconnecting frame and isolation apparatus which eliminates transverse forces relative to the two threaded members. The power-driven lead tong rotatingly drives the first threaded member about its axis either clockwise or counterclockwise, as required. The back-up tong secures the second threaded member against axial rotation in response to the rotation of the first member. The interconnecting frame and isolation apparatus adapts the lead tong to the back-up tong in such a manner that their relative tendencies to rotate about the threaded members, in opposite directions, counteract each other. Also, by means of interconnecting members and isolation apparatus allowing relative movement along x, y and z axis between the lead tong and the back-up tong, but which does not allow relative rotation about the z axis, the interconnecting frame prevents undesirable transverse forces from occurring, between the lead tong and the back-up tong in response to the driving torque of the lead tong. Further, by means of said interconnecting members and isolation apparatus, the interconnecting means eliminates transverse forces which would otherwise develop because of irregularities of the threaded members (such as bent members or eccentric lead). A load cell cooperating with the isolation apparatus, internally disposed in the interconnecting frame, cooperates between the isolation apparatus and the tong housing to produce a torque measurement without inducing transverse forces on the threaded members.
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