Is it correct to say that the carbon content in the materials used for welding pressure vessels is less than or equal to 0.25%?
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Is it correct to state that the carbon content in the materials of pressure vessel components that are subject to stress and those that are not subject to stress, as used in welding, is less than or equal to 0.25%? Dear sea friends, please join the comments.
I think this statement is completely correct, while the answer to the old question is wrong.
This post was last edited by fzujunru on 2015-10-7 at 13:14. Clause 2.3 of the Fixed Capacity Regulations specifies that for welding, carbon steel and low-alloy steel with C≦0.25% should be used
You should take a look at the main premise earlier; the standards specify that steel should be used for stressed components. Does steel used for unstressed components also need to meet this requirement?
The specifications do not specify whether it is steel for pressure-bearing components, or steel for welding non-pressure-bearing components, requiring a carbon content of 0.25% or less. In other words, for any welding steel, whether it is used for pressure-bearing components or non-pressure-bearing components, the value must be less than or equal to 0.25%. The old code emphasized the use of steel for the main pressure-bearing components.
This is mainly due to considerations regarding welding performance......
Following the new capacity regulations is correct. Article 2.3.1 of the revised specification states clearly: Carbon steel and low-alloy steel used for welding: C≤0.25%, P≤0.035%, S≤0.035% ； According to the old regulations, this is incorrect – “Used for the main pressure-bearing components of welded structural pressure vessels”……”
The specifications do not specify whether it is steel for pressure-bearing components or steel for welding non-pressure-bearing components, requiring a carbon content of 0.25% or less； In other words, whether it is steel for stressed components or for unstressed components, the value must be less than or equal to 0.25%.
Unstressed members can be greater than 0.25, such as Q235B.
According to the definition in the \"Code for Fixed Pressure Vessels\" (page 41): Clause 2.3.1 of this code specifies the minimum technical requirements regarding carbon, phosphorus, and sulfur for all carbon steel and low-alloy steels used for welding in the pressure-bearing components of pressure vessels, including both general-purpose steels and specialized steels. Non-compressed elements are not included. For non-compressed elements that are not welded directly to the compressed elements, there is no need to limit the carbon content ； Unstressed components that are welded directly to stressed components may comply with the requirements specified in NB/T 47042-2014 \"Horizontal Vessels\", clause 5.3. Materials such as plates, tubes, and forgings used for unstressed components like important internal parts and reinforcement rings must meet the requirements specified in clause 5.1 (i.e., the requirements for materials of stressed components) ； NB/T 47041-2014 \"Tower-Type Containers\" 5.2 Non-compressed components 5.2.1 The metal materials used for the non-compressed components of tower-type containers shall be those specified in material standards. When welded to stressed components, it should be a metal material with good weldability. 5.2.2 The metal materials used for the skirt shell are divided into those for the transition section and those for the main body of the skirt shell; the material selected for the transition section should be the same as that of the tower shell with which it is welded together. (It can be understood that the material of the skirt transition section should meet the requirements of materials for compressive members; it is likely incorrect to include all non-compressive elements under the floor category.)