A tubesheet is a flat metal plate with holes drilled to allow the passage of tubes in a heat exchanger. It is located at the ends of the heat exchanger and serves as a support for the tubes. The tubes are either welded or expanded into the holes of the tubesheet to ensure a tight and secure fit. The tubesheet is typically made of materials such as carbon steel， stainless steel， or non-ferrous alloys， depending on the specific application and operating conditions. It plays a critical role in maintaining the structural integrity and efficient functioning of the heat exchanger by providing support， preventing leakage， and facilitating the transfer of heat between the two fluids in the exchanger.