Thermally-actuated steam trap

Abstract

In a thermally-actuated steam trap, a valve casing is formed therein with an inlet, a valve chest and an outlet, and a valve seat member is disposed between the valve chest and the outlet. Within the valve chest, there is further provided a temperature control element including two disk-like wall members and a diaphragm member provided between the wall members. The diaphragm member is secured at the peripheral edge to both the wall members, and the inner space formed thereby accommodates an expansible medium. The diaphragm member carries a valve member cooperating with the valve seat member at the side opposite the expansible medium side, and in the central region of the valve member directed toward the diaphragm member is provided a recess portion which becomes deeper as it proceeds toward the center. At least one sheet of the diaphragm member is held between the valve member and a holding member formed substantially corresponding to the space within the recess, and the valve member, diaphragm sheet and holding member are welded with each other in the region where the diaphragm sheet is held between the recess of the valve member and the holding member.