What is the weld joint coefficient at the shell openings in opening reinforcement?
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When calculating the reinforcement for openings in pressure vessels! What should be the weld joint coefficient at the opening in the housing? Under what circumstances should one choose 1, and under what circumstances should one choose something else? ! It’s best to indicate the source!
The welding joint factor has nothing to do with openings; according to clause 6.1.4 of Part GB150-2011, openings on containers should be avoided in areas near the container’s welding joints. When the opening passes through or is adjacent to a weld joint in the container, it must be ensured that there are no defects exceeding the specified limits within a 2dop radius around the center of the opening; in other words, all welds within this range must be inspected for defects ； As for the regulations on the selection of welding joint coefficients, they are specified in Part 1, 4.5.2.2 of GB150-2011
However, in GB150.3-2011, clause 6.3.3.2, formula (6-1) uses δ, which refers to the calculated thickness at the opening in the shell. This calculated thickness uses formula (3-1) in 3.3 of GB150.3-2011, which includes the welding joint coefficient! ! The calculated thickness at the opening of the shell and the calculated thickness of the shell itself should not be the same, right?
When the hole is located in the weld, a welding coefficient is required; if it is not in the weld, the value is 1. However, even when the hole is in the weld, there are differences between longitudinal and circumferential seams, and ASME provides detailed explanations on this.
In other words, in accordance with the requirements of 6.1.4 in GB150.3-2011! Is the welding joint coefficient 1? Are there detailed instructions there? Or explanations and such! ! ! !
GB150-2011 only provides guidelines for the inspection of Class A/B welds; however, what you mentioned appears to be a Class D weld, which generally requires 100% penetrant or magnetic particle testing. The weld factor is determined based on the requirements for Class A/B welds
Actually, it can be considered comprehensively. Since in design it is often not known how the production will arrange the cutting, and it is impossible to predict whether there will be welds at the cutouts, the coefficient used in the design calculations is generally the same as that for the main structure. However, when it can be confirmed that there are no welds within the 2dop range, then the coefficient can be set to 1.