The connection methods of heat exchange tubesheets and tubesheets plate are expanded, welded, expanded and welded. Because the utility model has the advantages of simple structure, low manufacturing cost, can get the smaller diameter of the shell and tubesheets process can be divided into various, shell is also available longitudinal baffle into multi pass tubesheets plate heat exchanger is the heat transfer principle, through of cold and hot material and heating or cooling medium of the reverse flow heat exchange, so as to achieve the material is cooled or heated, is widely used in engineering available as an evaporator, a heater, a condenser and cooler.

Commonly used process manufacturing methods have the strength of expansion, expansion, strength and seal welding. Strong expansion degree connected with a finger to ensure the heat exchange tubesheets and tubesheets sheet connection sealing performance and tensile off the strength of the expansion joint; adhesion expansion means to eliminate the heat exchange tubesheets and the tubesheets holes between the gap of mild expansion joint; welding strength that can ensure the heat exchange tubesheets and tubesheets plate connection sealing performance and tensile strength of welding; a tight sealing to ensure the welding of the heat exchange tubesheets and tubesheets sheet connecting and sealing performance.

At present, the conventional heat exchange tubesheets is usually used in the mode of "bonding expansion and strength welding", but the important or the use of harsh heat exchanger requires the use of "strength expansion + seal welding" mode. Expansion, welding and the structure by the expansion joint and welding in the process of sequence can be divided into the first expansion after the first and then after the expansion of the expansion of two. For the conventional design of the "paste expansion and strength welding" can be used after the first expansion of welding, and the special design of the "strength of the expansion and strength welding" can be used to post expansion, and then strength welding, the final strength of the expansion method. For the first welding process, the control of the tubesheets and tubesheets plate hole and the accuracy of the main problem. When the gap between the tubesheets and the tubesheets plate cavity is smaller than a certain value, the expansion process will not damage the quality of the welded joint.