| 摘要 |
An apparatus for gripping tubular members about their outer diameter without causing surface damage or structural deformation to the tubular members, so that they may be axially rotated or secured against axial rotation. A generally cylindrical internal sleeve is contained within a molded flexible liner. One side of the internal sleeve is releasably attached to the flexible liner, forming an annular bladder-like structure within the flexible liner. Introduction of pressure into the bladder-like structure causes the flexible liner to inflate radially inward and thereby grip tubular workpieces within the friction grip. Axial splines on the releasable side of internal sleeve interfit mate with corresponding splines of the molded flexible liner, thereby evenly distribute torque forces throughout the flexible liner rather than such torque forces being concentrated at only the edges of the flexible liner. Movable anti-extrusion rings at the axial edges of the flexible linear prevent deformation of the liner into the annular space between the outer sleeve of the friction grip, and also prevent wear between the axial edges of the liner and the edges of the outer sleeve. An additional, non-rigid sleeve, or coating, of friction enhancing material may be placed on the inner face of the flexible liner to increase the frictional characteristics of the grip and/or increase service life of the surface of the flexible liner. Instead of being made of one annular section, the friction grip may be made of two, or more, hingedly connected sections so as to allow the gripper to be attached at the midpoint of tubular workpieces without having to slide it over one end of workpiece.
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