Is hydrogen elimination treatment an important factor in PQR?
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We know that post-weld stress relief treatment is an important factor in PQR. Is hydrogen elimination treatment an important factor in PQR? Give your opinion
It should not be counted. The purpose of hydrogen elimination treatment is to postpone the post-weld heat treatment to avoid delayed cracks in the weld during this period.
I don’t think so. Heat treatment in PQR only mentions post-weld heat treatment, and it is also explained as a heat treatment to eliminate residual stress or change the organizational structure. The function of hydrogen elimination is only to release H atoms from the assembly joint to buffer time. There is no phase change or response effect.
Let’s look at the definition first, it’s from ASME. Post weld heat treatment definition, any heat treatment performed after welding. Post-weld hydrogen elimination treatment is defined as holding the completed or partially completed weld at a high temperature below 425 degrees in order to allow H to diffuse out of the weld. Let’s look at the PWHT type again. ... heat treatment below the lower transformation temperature ...
For domestic ones, you can refer to JB 4708 Table 1. It is only a minor factor. ASME places post-weld hydrogen elimination treatment in "preheating". Please refer to QW-406.11 (I use 07ED + 08AD). For the commonly used welding methods that I am exposed to, such as SMAW SAW GTAW, etc., hydrogen elimination treatment does not belong to any variable (will not be considered)
I don’t know much about this, but seeing that there is no hydrogen elimination item in our company’s PQR, it means it doesn’t exist.
Definition of important factors in PQR: Refers to factors that affect strength performance. Hydrogen elimination treatment plays a role in avoiding delayed cracks and does not affect strength.
Not considered an important factor and will not be considered