With inspection at different stages of the manufacturing process, the inspector examines the work and documents the inspection results.

The inspection range of heat exchangers is listed below:
(1) Identification and inspection of raw materials

(2) To approve the welding process completed on the test plate

(3) To examine welders’ qualifications

(4) Welding groove preparation, including visual inspection of layering and penetration flaw detection

(5) To check the quality of welding preparation and welding seam pairing

6) To check the welded joints on the back of the groove, such as the welds of the placement type takeover, because the welds in these places are inconvenient

(7) Radiographic inspection

(8) To penetrate flaw detection to cover layers; to test the chemical composition of cover layers; to measure ferrite content

(9) The alignment of longitudinal welds and girth welds

(10) The size deviation of a single barrel section

(11) Pair inspection of a barrel section and parts

(12) The gap of the root bead before welding

(13) To check the appearance contours of welding seams and welding defects

(14) Inspection of prefabricated parts and purchased parts

(15) To check the radiographic inspection or other welding inspection techniques

(16) The thinning amount of the head after molding

(17) To check the alignment of the tube plate and the shell after drilling

(18) Before the welding operation, to check the pairing of the tube sheet and the shell

(19) On-site witness after post-weld heat treatment

(20) Dimensional inspection after a hydraulic test

(21) Issuance of container stamps and certificates of conformity

(22) Packaging and shipping