A pipe clamping tool for providing a treatment to a pipe workpiece comprising: a clamp assembly, including a handle, a clamp base and first and second adjusting links (44, 46) operatively coupled to the handle such that the first and second adjusting links (44, 46) are extendable from and retractable into the clamp base via movement of the handle; a first jaw coupled with the clamp base and the first adjusting link via a first linkage (30, 31, 32, 33), the first jaw comprising a first workpiece contacting surface; a second jaw coupled with the clamp base and the second adjusting link via a second linkage (24, 25, 26, 27), the second jaw comprising a second workpiece contacting surface; wherein the first and second workpiece contacting surfaces (21, 23) together form a generally cylindrical shape for grasping the workpiece; the first and second adjusting links (44, 46) are operatively coupled to the first and second jaws (20, 22) via the first and second linkages (30, 31, 32, 33, 34, 24, 25, 26, 27, 28) such that a first movement of the handle causes the first and second adjusting links (44, 46) to retract into the clamp base and the first and second jaws (20, 22) to move towards one another, while at least a portion of each jaw remains generally parallel, and a second movement of the handle causes the first and second adjusting links (44, 46) to extend from the clamp base and the first and second jaws (20, 22) to move to separate from one another, while at least a portion of each jaw remains generally parallel; and the workpiece contacting surfaces (21, 23) are adapted to contact the workpiece around its outer diameter and to apply a selected treatment to the workpiece, wherein the pipe clamping tool is configured to apply the selected treatment to the workpiece without disturbing a flow of fluid through the workpiece. a clamp assembly, including a handle, a clamp base and first and second adjusting links (44, 46) operatively coupled to the handle such that the first and second adjusting links (44, 46) are extendable from and retractable into the clamp base via movement of the handle; a first jaw coupled with the clamp base and the first adjusting link via a first linkage (30, 31, 32, 33), the first jaw comprising a first workpiece contacting surface; a second jaw coupled with the clamp base and the second adjusting link via a second linkage (24, 25, 26, 27), the second jaw comprising a second workpiece contacting surface; wherein the first and second workpiece contacting surfaces (21, 23) together form a generally cylindrical shape for grasping the workpiece; the first and second adjusting links (44, 46) are operatively coupled to the first and second jaws (20, 22) via the first and second linkages (30, 31, 32, 33, 34, 24, 25, 26, 27, 28) such that a first movement of the handle causes the first and second adjusting links (44, 46) to retract into the clamp base and the first and second jaws (20, 22) to move towards one another, while at least a portion of each jaw remains generally parallel, and a second movement of the handle causes the first and second adjusting links (44, 46) to extend from the clamp base and the first and second jaws (20, 22) to move to separate from one another, while at least a portion of each jaw remains generally parallel; and the workpiece contacting surfaces (21, 23) are adapted to contact the workpiece around its outer diameter and to apply a selected treatment to the workpiece, wherein the pipe clamping tool is configured to apply the selected treatment to the workpiece without disturbing a flow of fluid through the workpiece.