What category do the weld joints formed by welding the internal components to the shell in pressure vessels belong to?
Thread Content
Similarly, what category do the weld joints formed between the internal components and the shell in pressure vessels fall into? What category is generally assigned to them? Class D? Still. . .
It belongs to Class D welds; however, some organizations classify them as Class E welds. But there is no Class E for 150, so I think Class D is more appropriate, as in the diagrams for 150, the welds between the reinforcement rings and the cylinder are also classified as Class D. Last edited by yaoyongyoyo on 2009-3-19 15:44.]
Generally, in accordance with the GB150 standard, we only code welds such as reinforcement rings, supports, and skirt bases that are welded to the cylinder body as Class C welds； The inner parts are generally not coded.
The welds between the internal components and the cylinder are not controlled, as it does not belong to a pressure-bearing element! It’s a different story if there are two chambers.
It is classified as Category E according to the welding manual, but no category is assigned under GB50, as it is not a pressure-bearing weld!
That’s how I think it is; if no categories are used, it still needs to be supported by process evaluation, and it has to appear within the welding process – without a number, it’s difficult to identify it. Classifying it as Class D seems inappropriate; the drawings often require 100% MT for all items in Class D. Wouldn’t that be overly unnecessary for components inside a tower? Classified as Category E – isn’t it specified in GB150?
Such welds do not require a welding procedure card; they belong to Class D and Class E welds
Is it necessary to classify welds that are not controlled?
For applications that are not under pressure, Category E applies; that is, welding must be carried out with the support of process evaluation, but it is not necessary to prepare separate process cards or records, nor is testing required (unless specified in the drawings)
Since it’s uncontrolled, there’s no need to classify it
Thank you all for your comments; I personally agree more with “Camel Xiangzi”. Controlled, non-pressure-bearing.
It does not belong to pressure-bearing joints; in my opinion, it should not be classified as such.
It can be classified as Category D, but testing may not be required. Such welds are uncontrolled, and no welding procedures are required during welding.
The welds between the reinforcement ring and the cylinder are also not under compression; why are they classified as Class D? (GB150)
It seems this issue was discussed before. I believe such cases are not covered by these regulations; testing can be carried out in accordance with the standard procedural guidelines.
I think categories should not be established; the welding of the internal components to the cylinder does not fall under the category of welding on pressure-bearing parts
If such welds are considered important, refer to the weld treatment for lugs (the so-called Class F welds?) ）
According to the GB150 standard, it is classified as a Class D weld, but since the internal component welds are not compression welds, there is no need to specify the weld type.
This basically falls in a gray area; it depends on how you approach the design. Classifying it as Category D is certainly a safer option, but it will increase the workload on site.
The welds of the internal components do not need to be inspected and managed in the same way as CD-type welds; they should not be classified as D-type welds. It is sufficient that the welding location and quality be good