Tube sheet, which involves drilling holes slightly larger than the pipe outer diameter on a circular steel plate, serves as a round steel that fixes the tubes and seals the medium in a heat exchanger. It is a fitting that allows the tube to be inserted and welded in place, fulfilling this function.

The precision of tube plate processing, particularly the spacing and tolerance of tube holes, diameter, perpendicularity, and smoothness, significantly affects the assembly and operational performance of the listed chemical equipment.

The tube plates for pressure vessels of Class 3 and 4 require higher precision. Traditional hole processing methods include fitter marking and arm drill boring. As chemical vessels become larger, the diameter of tube plates also increases, and their thicknesses gradually thicken. CNC technology is now introduced for tube plate processing, with CNC drilling machines commonly used for pilot hole creation in conjunction with arm drills for hole machining. High-precision hole processing using machining centers is increasingly accepted by some large enterprises. There is a growing demand for large, thick tube plates in the nuclear power, seawater desalination, and central air conditioning heat exchanger fields.