Dear metenger
my question is about the acceptance criteria of misalignment in tube to header connection.
Is it PW-33 or PW-34?
our client told us that we shall use PW-33 for misalignment ,But I think he is wrong and we shall use PW-34. Because PW-33 is for shells and vessels.
according to ASME SecI PW-33 is for evaluating misalignment of shells and vessels, and PW-34 is for evaluating misalignment of tubes and pipes. I want to know which part I can use for the weld between tube to header in harp of cobined cycle powerplant. PW-33 or PW-34?
we had a mistake in drilling one hole in a header of a harp (hrsg boiler).
we want to build up the wrong hole by welding and again drill another hole in proximity of repaired area.
Is it permitted or prohibited according to ASME SecI or any other technical codes?
If it is permitted , is there...
Dear metenger
wrinkles don't cause out of roundness and pipes have been checked by ultrasonic thickness gage and no problem were reported.
Dear Duwe6
according to PFI ES-24, for our pipes maximum acceptable Buckle height is about 0.2mm ,but the actual wrinkle height in worst case is 1.5mm.
Is there any criteria for wrinkle on the surface of pipe during bending of the pipe?
we are boiler maker and in bending of some pipes which we have purchased from Romania, we confront this defect.
according to our technology transfer documents , wrinkle is not acceptable. But I don't know the...
During the checking of pipe thickness(A106)by ultrasonic thickness instrument, I found some spots(just some spots in the whole pipe) which where under minimum allowable thickness(12.5%). What shall we do in this case as far as we purchase so many pipes from china?
Dear friends
according to QW-202.4, thickness of both thinner and thicker member shall be within the range permitted by QW-451.So we shall consider the thicker member. In this kind of joint I don't know what is the thickness of the thicker member. Is it 50mm,20mm or 40mm?
We have a joint between two dissimilar thicknesses that attach a pipe to an end plate. According to the attachment drawing,thickness of the end plate is 40mm (50mm in the attachment point)and the thickness of the end plate in another direction is 20mm. Which thickness shall be considered in PQR?
AWs D1.6 is designed for sheet stainless steels of more than 2mm. Which standard should we use to weld 1.5mm stainless steel sheets? in table 4.2.B of AWS D1.6 minimum qualified thickness is 3mm! so what should we do about the lesser thicknesses?
Can we use pqr of CJP V groove type for other groove type(e.g double V- groove or single bevel and... ( square- groove is excluded)) in WPS of CJP groove welds ?
Hi,
After welding P91 steel (P No. 5B), we perform post heat treatment at 300 deg.C for 4hr and then PWHT at 745deg.C for 2hr. If we perform PWHT exactly after welding (without any delay), post heat is required or not?
Why shall we perform post heat treatment?
Regards