Non-destructive testing of pressure vessel welds
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For the non-destructive testing of pressure vessels, in addition to the longitudinal ring seams on the cylinder body and the welds between the nozzles and the shell, it also includes the welds connecting the various components themselves to the shell. Relevant standards set requirements in this regard; these mainly include the skirt base itself and its connection to the shell, as specified in 8.4 of NB/T47041 and 8.6 of SH/T3098； The lug body and its connection to the housing are specified in 5.4 of HG/T21574 ； Ear seat, rigid ring body, and their connection to the housing: refer to 7.9 of NB/T47065.3 and 8.8 of NB/T47065.5 ； Container flange, see 6.6.1 of NB/T47020 ； Head, see 6.10 of GB/T25198 ； Reinforcement ring, see NB/T 11025’s 5.3.9 and 5.3.10 ； Corrosion-resistant layer surfacing, see 9.4 of HG/T20584. Expansion joint, see 8.5 of GB/T16749-2018. Welding of heat exchange tubes to the inner holes of the tube sheet (GB/T151 4.6.5), butting joints of heat exchange tubes (8.3.4), butting joints for joining the tube sheet and the flat covers of the tube box, surfacing layers (8.4), as well as the surfaces of tube-sheet corner joints and radiographic inspection.
The non-destructive testing of pressure vessels covers a wide range; according to different standards, the main objects of inspection and relevant requirements are as follows: 1. The skirt base itself and the welds connecting it to the shell, in accordance with Clause 8.4 of standard NB/T47041 and Clause 8.6 of standard SH/T3098. 2. The lifting lug itself and its welding joint to the housing shall comply with Clause 5.4 of standard HG/T21574. 3. Ear studs, the rigid ring body, and the welding joints connecting them to the shell shall comply with Clause 7.9 of standard NB/T47065.3 and Clause 8.8 of standard NB/T47065.5. 4. Container flange, refer to clause 6.6.1 of standard NB/T47020. 5. Head, refer to clause 6.10 of standard GB/T25198. 6. Reinforcement rings: Refer to clauses 5.3.9 and 5.3.10 of standard NB/T 11025. 7. Corrosion-resistant layer surfacing, refer to clause 9.4 of standard HG/T20584. 8. Expansion joints, refer to Clause 8.5 of standard GB/T16749-2018. 9. Welds between the heat exchange tubes and the inner holes of the tube sheet shall comply with clause 4.6.5 of GB/T151 ； For the butt joints of heat exchange tubes, refer to clause 8.3.4 ； For the butt joints at the splicing of tube sheets and tube box flat covers, as well as the surfacing layers, refer to clause 8.4 ； As well as the surface of pipe-to-tube sheet corner joints, radiographic inspection, etc. .