Welding Copper Beryllium Molds: What You Must Know
Beryllium is a harmful element and warrants caution when welding.
Finding a reliable welder is not always easy when your molds need repair (seeLeaving Your Welding to a Pro, MoldMaking Technology magazine, December 1999, page 21 for tips), finding a welder who welds copper beryllium is even more difficult. According to Tom Schippert, vice president of MPD Welding (Orion, MI), if copper beryllium is involved, their name usually comes up since most welders don't want to handle this hazardous material.
"It's not that common to find welds with copper beryllium - it depends on the industry," Schippert notes. "There are certain applications where it is the material of choice because they are trying to get the heat out of the mold, so the part comes out of the mold and cycle faster. However, in our experience, beryllium is dangerous to work with and people can become seriously ill when welding it. Certain precautions are necessary, like purging the area by drawing off any of the fumes with smoke eaters and having the operator himself wear a mask and make sure that his workpiece is positioned so the fumes are taken up and out."
Precautions notwithstanding, Schippert explains that the welder needs to know certain facts from the moldmaker before welding can occur. "First, we need to know why we are welding the mold," he says. "Is it an engineering change or has the mold-maker run cutter path where it ought to have not gone or is the mold being modified?"
Then, it's up to the moldmaker to provide answers for the welder to the following questions: "What are you trying to accomplish, and what does the finish have to be so that the welder can get enough material on there so the moldmaker can finish the mold back to where he wants it to be," Schippert comments. "Generally speaking, the moldmaker needs to communicate what he wants to have done so the welder - at that point - knows what he has to do."
No special preparations are necessary, Schippert maintains. "All of the prep work is done by the welder," he notes. "If at the time it is found that the mold and the welding needed to be done in the rib area, for instance, the welder would have to clear out an area big enough so that they could get down in there and weld. In cases like this, there may be some premachining that has to be directed to the moldmaker prior to getting the mold in-house - if it was an inaccessible area. But as a general rule, that's not the case."
How much time the weld will take depends on how much welding is actually going to take place, Schippert adds. "It's a pretty straightforward process," he notes. "It's just a matter of finding someone willing to work with the material."
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