Must the weld joints of the casing and pipes in a type of steam distribution cylinder necessarily adopt a fully penetrative structure?
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This post was last edited by The wise are not confused on 2009-9-20 14:35. Must the weld joints of the casing and pipes in a split-type cylinder always adopt a fully penetrated structure? Is it also necessary to have inward-reaching reinforcement? Note: The pressure in the steam cylinder is 0.8 MPa, the temperature is 200 degrees, the diameter is 500 mm. For the nozzles with a diameter of 219 mm, is full penetration still required for the welding joint? The problem arose because the equipment was transported to another location and, after installation, the inspection agency reviewed our drawings and stated that the connections and the casing had to be constructed with full penetration welding; the drawings were incorrect, and they would not accept them unless they were corrected, demanding that the equipment be returned. Is **’s scope of responsibilities too broad?
Welded joints of containers generally require a fully penetrated design. When the weld joint between the shell and the nozzle is not fully penetrative, it can only be used in conditions with no sharp temperature gradients. Therefore, non-full penetration joints are not used in practical work, and the same applies to reinforcement structures.
Internal reinforcement is generally used. The full penetration configuration is generally used. The key to the issue is that the environment in which the steam cylinder is used, as well as the temperature of the medium, etc., all affect the specific requirements for the equipment
Yes. If the cylinder is too small, grooves must be made for welding to ensure full penetration. If internal reinforcement is used and full penetration is not achieved, then the extended portion cannot serve as a reinforcement. Double-sided welding should be used whenever possible. (Generally, it seems there’s no small-diameter inward-reaching reinforcement structure, right?) I’m not sure if I remembered it wrong. ) Take a look at the welded structures in Appendix GB150.
Looking at it that way, what kind of pressure is there? To determine whether full penetration is required, one can refer to the requirements specified in the tolerance standards
Full penetration welding is required between the tube sections as well as between them and the end caps; see Article 51 of the specifications for details. The requirement for full penetration between the take over and the shell is specified in detail in Article 54 of the tolerance specifications.
I encountered such a problem at work: we use a structure with incomplete weld penetration, but when the equipment was sent to another location, the supervisor at the local inspection agency insisted that the weld joints must have complete weld penetration. When asked for evidence to support this requirement, he refused to provide any; he simply said that he would accept the work if it had complete weld penetration, but he wouldn’t accept the documents otherwise. What do you think should be done in this situation? Note: The pressure in the steam cylinder is 0.8 MPa, the temperature is 200 degrees, the diameter is 500 mm. For the nozzles with a diameter of 219 mm, is full penetration still required for the welding joint?
;P There’s nothing you can do when you run into someone like you who likes to meddle – the common people can’t fight against the officials. Show him the two provisions of the tolerance regulations and see if you can convince him. ;P
Article 54 of the pressure vessel regulations specifies clearly the requirement for full weld joints in the connection between the pipe and the shell. Your drawings should also have been reviewed by your local pressure vessel supervision agency before the equipment was manufactured. You can discuss this situation with the staff at your local pressure vessel supervision agency to see what they think; if possible, ask them to communicate directly with the head of the pressure vessel supervision agency at the installation site.
Although the regulatory standards do not require full penetration, for this type of Class D weld, we always use a design with full penetration. The internal standards of our company should be higher than those set by regulations anyway. Moreover, achieving full penetration doesn’t cost much more in terms of money or time, but it avoids many unnecessary problems.
Personally, I don’t think a fully penetrated structure is necessary; the tolerance specifications make this clear. For smaller steam cylinders, this is how we carry out the welding.