Almost all tube sheets in shell and tube heat exchangers are machined, and their hole diameters and spacing have different tolerance standards according to different tube bundles. Line drill, fixture drill or CNC machine tool can be used for drilling. However, if the line drill is used, because the accuracy of this method is not very high, when drilling the baffle hole, it is necessary to stack the tube plate and baffle plate together to cooperate with the drilling. After completion, the baffle number corresponds to the direction diagram for easy assembly. For shell and tube heat exchangers, it is best to drill holes with a complete circular plate, and then make the circular plate into its own shape.
In the production of shell and tube heat exchanger, the manufacturing method of shell and tube and head is similar to that of most vessels. The difference is that its requirements are different. Pay attention to material inspection, drilling of tube plate and baffle corner hole, connection of tube shell and fabrication of flange. At present, the production of shell and tube heat exchanger generally adopts the traditional process, in which more welding is used. Therefore, the manufacturer must make detailed connection according to the welding process, and also need to test the welds.