A shuttle machine for transporting work pieces for a sealing press or other machine tool is disclosed. It has two conveyers for transporting work pieces. The two conveyers are supported by a frame to move back and forth in opposite directions. When the two conveyers are in a first position, a second section of the first conveyer and a first section of the second conveyer are located near the tool, while the first second of the first conveyer and the second section of the section conveyer are accessible to first and second operators, respectively. Both operators can unload and reload work pieces simultaneously while the tool operates on the already loaded work pieces. When the conveyers are moved to a second position, the sections previously operated on are accessible for unloading and reloading, and the sections just loaded are operated on. A related operating method is also disclosed.