Regarding heat treatment issues
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The equipment’s housing has a thickness of 20 mm. There is a forged fitting on this housing with a DN500 diameter and a wall thickness of 56 mm. On this thick-walled pipe, there is another fitting with a DN50 diameter and a wall thickness of 6 mm. On the flange cover of the DN500 fitting (with a diameter of 64 mm), there is yet another fitting with a DN100 diameter and a wall thickness of 14.5 mm. Since the entire equipment needs to undergo heat treatment, should the maximum of these thicknesses—64 mm—be used as the value for heat treatment calculations? When calculating the heating and cooling rates, GB/T30583-2014 specifies that the maximum thickness of the welded component’s shell should be used. For the equipment assumed earlier, should 20 mm or 64 mm be used for these calculations? Could some senior please explain this? Thank you! :)
Section A.5 of GB/T30583-2014 specifies that the heat treatment thickness for the cylinder and the nozzles shall be the greater of the two values.
How to determine post-weld stress-relief heat treatment?
The original poster didn’t specify what materials they are made of
Q345R, forged 16MnIII,
In GB/T30583-2014, when connecting elements such as A5 nozzles and manholes are welded to the cylinder shell and heads, δPWHT is taken as the maximum value among the thickness of the weld at the neck of the connecting element, the thickness of the cylinder shell welds, the thickness of the head welds, or the thickness of the fillet welds on the connecting elements. But in the example I gave, the joints are of the plug-in type, not the fixed-type; the 56mm and 64mm welds are on the thick-walled pipe and the flange cover – which of these welds do they fall under? There is another question: in 4.4.9 b) of GB/T30583-2014, δ refers to the maximum thickness of the welded component’s shell – is it still necessary to take into account values such as 56 mm and 64 mm as shown in the example?
I think it should be based on a shell thickness of 20 mm.
These two issues relate to the heat treatment processes involved in the manufacturing process. Could you please explain them in detail? I have little knowledge regarding stress and loads, so I’m not quite sure. Thank you!
Could you explain in detail the basis or reasoning behind it?
GB/T30583-2014 has relevant provisions
Could you explain it in detail? The problem arises because the standard isn’t understood thoroughly. Please explain it specifically, thank you!