Tube sheet, which is a circular steel plate with holes slightly larger than the tube outer diameter, serves as a round steel in heat exchangers for fixing tubes and sealing media. A fitting that inserts the tube and welds it in place to perform this function.

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

Pipe plates for Class 3 and 4 pressure vessels require higher precision. Traditional hole processing methods include fitter marking and arm drill boring. With the large-scale of chemical containers, the diameter of pipe plates has been increasing, and their thickness is gradually thickening. CNC technology has been introduced into pipe plate processing, with CNC drilling machines commonly used for initial holes, complemented by arm drills for hole processing. High-precision hole processing using machining centers is increasingly being adopted by some large enterprises. There is a growing demand for heavy-duty pipe plates in the nuclear power, seawater desalination, and central air conditioning heat exchanger fields.