Flange fillet weld inspection

Not all are necessary; it depends on the circumstances. Refer specifically to GB150.

Reply to the message: **General Administration of Quality Supervision, Inspection and Quarantine** Question: Can paragraph 3 of Article 4.5.3.1 of the Safety Technical Regulations for Fixed Pressure Vessels be interpreted in two ways as follows: (1) Paragraph 3 of Article 4.5.3.1 merely specifies the methods for non-destructive testing, and it is up to the designer to decide whether surface testing is required? (2) Does Paragraph 3 of Article 4.5.3.1 require surface inspection to be carried out on all fillet welds of Class D joint sockets? Are the pipe seat fillet welds considered to be all Type D joints? Which of these two interpretations should be followed? (3) As stipulated in Paragraph 3 of 1.6.1 of the Safety Technical Inspection Regulations for Fixed Pressure Vessels, the reinforcement rings are no longer considered primary pressure-bearing components. However, current standards require 100% RT inspection of the welds joining these reinforcement rings. Our company plans to adopt a half-ring structure for all reinforcement rings in order to ensure full penetration of the welds at the root of the connections; therefore, we propose to omit 100% RT inspection of the welds joining these reinforcement rings. Is this acceptable? Answer: 1. Paragraph (3) of 4.5.3.1 is newly added to specify the methods for non-destructive testing of pipe socket fillet welds, pipe-to-plate weld joints, weld joints between dissimilar steels, and weld joints prone to reheat cracking or delayed cracking. For these stress concentration areas and metal materials prone to cracking, surface non-destructive testing should be added on top of the existing non-destructive testing requirements. This refers to the choice of methods, not proportion requirements; whether to carry out these non-destructive tests is determined by the designer in accordance with the relevant product standards ； 2. The regulations represent the minimum requirements; the reinforcement rings must also meet the requirements of the applicable standards.

I understand that socket-type fillet welds are classified as Class D welds, requiring 100% magnetic particle or penetrant testing