Welding line energy and plate thickness issues
Thread Content
The formula for calculating the welding line energy shows that it is related to the welding current, voltage, and welding speed. The method for assessing welding line energy is to determine whether the impact toughness value meets the relevant standard requirements. However, in actual welding operations, the selection of welding current, voltage, and welding speed varies depending on factors such as plate thickness, wire diameter, and groove shape. And according to the definition of impact toughness: the ability of a material to absorb energy during plastic deformation and fracture ； 1. Is the energy absorbed per unit length different for different plate thicknesses? Is there a direct relationship between welding line energy and plate thickness? If I create a WPS for Q345R material with a thickness of 8 mm, where the maximum line energy is 22 KJ/cm, then assuming I want to weld a plate that is 16 mm thick, could the welding line energy be higher than that specified for the 8 mm thickness in order to improve production efficiency? However, there is a problem: if the welding line energy is increased, it will be necessary to conduct new tests on impact toughness, which conflicts with the goal of improving production efficiency. For such issues, in companies with sound quality assurance systems, 16mm products are certainly welded using welding parameters of 8mm. However, in private enterprises, production efficiency is the priority, and it’s not practical to use parameters of 8mm. 2. Are there any good solutions to this kind of problem? (Does this also reflect the shortcomings in the weld evaluation?) ）
This isn’t a problem related to weld evaluation per se; it’s simply a case of not following the rules! What is the purpose of weld evaluation? Why is weld evaluation necessary? If efficiency is the only consideration when actually carrying out work, then can it still be ensured in many cases by using low-current, multi-layer, multi-pass welding? How to control the actual mass!
Thank you for your reply, but the quality assurance system here isn’t effectively implemented – the production department is in charge
It’s too difficult to work in technology or quality control in private companies!
Consider the number of welding layers. The weld is not formed in one go. To improve efficiency, the diameter of the welding wire (electrode) needs to be re-evaluated.
This is not a technical issue; on a minor scale, it’s a relationship issue, while on a larger scale, it’s a political issue
The line energy specified in the welding evaluation is given as a range; the manufacturing process can use the highest value of line energy, rather than the lowest one.
What is the purpose of weld evaluation for thicknesses over 8mm?