Why use integral forgings for manhole pipes and flanges?
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A defense question on high pressure vessels: Why are integral forgings used for manhole nozzles and flanges? Is it okay to separate? In the pictures I have seen, basically most of the nozzles are in the form of solid forgings. I think the main reason is that without welds, the integrity is better and there are no weld-related defects, which reduces possible risks and can improve the quality of the container and make it safer. In addition, if there is no weld, there is no need for flaw detection, which can save the cost of flaw detection. What other issues need to be considered?
The cost is too high! It is more economical to take over and process flanges separately!
This post was last edited by bluishice on 2021-9-11 07:47 For high-pressure vessels, cost is not the first consideration. Look at the Class A weld below. It doesn’t require RT-100%. How can we save the cost of flaw detection?
The main thing is to consider safety, reduce welds, and avoid welding defects. High-pressure equipment nozzles and manhole flanges generally have an integral structure. Generally, the outer diameter of the upper flange is smaller than the outer diameter of the lower butt joint. To make forgings, you only need to increase the height of the forging blank, add a ring seam, and then weld and flaw detect it. If it is not qualified, it will be repaired. The cost is not low. Considering safety and economic rationality, it is better to make it as a whole.