Can the equipment manufacturer determine the type of weld joint on its own?
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The drawings of pressure vessels designed in our country now specify in detail the types of various welding joints. However, many manufacturing units prefer to determine the type of welding joints according to their own characteristics (of course, full penetration is guaranteed). I wonder whether this approach is in line with the procedures. Please share your opinions!
This should work, as I’ve seen on many drawings that it states the manufacturing unit can decide on its own the type of welding groove, but it must ensure single-sided welding, double-sided welding, or full penetration welding, etc
As long as there is the appropriate welding procedure qualification and the code requirements are not violated (in some cases full penetration is required; please refer to the code), there will be no problem
As per the regulations, this is not allowed; the manufacturer must construct in accordance with the drawings. If the manufacturer wishes to change the type of joint, it must obtain the consent of the design party and provide corresponding design modification documents. Ensuring quality is one aspect; meeting standards is also an important factor. Drawings are the language of engineering; they are the legal documents that regulate projects, and care must be taken with them.
The types of welding joints indicated on some drawings are not necessarily reasonable; I think it would be more appropriate for the welding technicians to determine them, with the types shown in the design drawings serving as a reference
Generally, it is not possible; the design agency will indicate the welding method on the drawings, and the corresponding joint diagrams will also be included in them. If the design unit does not specify, the appropriate welding method can be determined based on the requirements of the welding process and the relevant standards. One cannot arbitrarily determine the form of the weld joint.
Sure. The welding process used by our company may not be exactly the same as what is specified in the drawings.
The manufacturing unit can decide for itself; it must first meet the requirements set by the design unit, such as full penetration, and secondly conduct the corresponding welding procedure qualification
The views from the 4th and 6th floors are correct; if the user unit has specific requirements, it is necessary to communicate with the design institute before starting the design, and this can be resolved as long as relevant regulations are not violated. Additionally, this does not apply to ordinary containers that are not within the scope of regulation.
It’s possible; the designer may not be an expert in welding techniques, and there might be inconsistencies in the design. As a result, during manufacturing, most of the weld joints are modified to suit the actual conditions.
In my opinion, it is not acceptable, as the type of welding joint can affect the determination of the welding coefficient. Any change to the joint type must be approved by the design team. If the design team provides a sample drawing to the manufacturing unit before finalizing the drawings, so that the person in charge of welding processes at the manufacturing unit can review it, this will ensure consistency with reality. It also helps the design team to choose the appropriate welding joint type, thereby avoiding unreasonable designs and unnecessary changes
The type of welding joint can be determined according to the characteristics of the respective unit. If only a weld evaluation has been conducted for the joint type and it is permitted by the standards, then the joint type can be used. For ordinary drawings, the A and B weld joints are typically shielded metal arc welding joints; however, as long as the thickness and diameter permit it, our company uses submerged arc welding instead, and neither the design institute nor the client has raised any objections.
What was said on the 2nd floor makes sense; it should be indicated on the drawings that the manufacturing unit can decide on its own the type of welding groove, but it must ensure single-sided welding, double-sided welding, or full penetration welding, etc. This should save a lot of trouble, and the inspectors won’t bother you. It is recommended that **uniform regulations should be established: the designer should specify the main requirements on the drawings (full penetration or partial penetration), while the type, size, and angle of the groove should be left to be determined by the manufacturing unit. As the guy on floor 11 said: The designers may not be experts in welding techniques, and there are unreasonable aspects in the design; therefore, during manufacturing, most of the weld joints were modified to suit the actual conditions.
Personally, I think it’s not possible. To change the type of welding joint, approval from the design unit is required. (Article 66 of the Compliance Regulations)
There shouldn’t be any problem, as long as it meets the requirements
I don’t know anything else; it seems that our company doesn’t use the HG20583 weld pattern entirely
The drawings provided by the design institute need to be converted by the manufacturing factory into production-ready layouts. The weld joints shown in the design drawings are usually not taken into account; people just follow their own methods, and there’s no need to indicate them on the drawings at all. Yet many design institutes still insist on including such details – it’s a form of bureaucracy. In some cases, it’s even unclear how welding should be done; they simply choose a method arbitrarily. It’s really pitiful
The weld joint types shown on the design drawings may not always be optimal; it is more appropriate for the welding technicians at the manufacturing plant to determine these types, with the designs serving as a reference. However, there are some special welding joints in the design drawings that require attention, such as those with large openings.
It should be done in accordance with the **standards for welding**. Strictly speaking, both the design drawings and the welder’s own modifications are incorrect.
As long as there is a qualified weld assessment, the choice of groove doesn’t matter
Changing the form of the weld joint, not the structure of the joint. Make adjustments in the manufacturing plant to suit the equipment and production processes of that specific plant. It is possible. But do not go against the designer’s intent. For example, you originally intended to weld through, but changed the joint design and failed to do so. Then it’s not allowed.