Workpiece clamping device

The invention discloses a workpiece clamping device which comprises a base and a fixed block fixedly arranged on the base, wherein a first rotating block and a second rotating block, which are positioned in the directions of an X axis and a Y axis of the fixed block are further arranged on the base in a rotating manner, a plurality of corresponding grooves are respectively arranged on the side surfaces of the first rotating block and the fixed block, which are adjacent to each other, a fixing part is arranged at the free end of the second rotating block, which is vertical to the extension direction of the second rotating block, and a locking rod is arranged on the fixing part in a threaded manner. When the workpiece clamping device works, the first rotating block rotates to one side of the fixed block, the grooves form a pipe groove which is matched with a pipe fitting to be processed, the fixing part of the second rotating block rotates to one side of the first rotating block, and the end part of a shrinking rod pushes against one side of the first rotating block. The workpiece clamping device can firmly lock the pipe fitting in the grooves through the matching between the first rotating block and the second rotating block; in addition, the installation and the detachment of the pipe fitting are convenient.