pad welding cast iron fits
pad welding cast iron fits
(OP)
Does anyone have a weld procedure for pad welding register fits on cast iron or cast ni-resist pump bowls/casings?
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pad welding cast iron fits
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RE: pad welding cast iron fits
Obviously, only one side of each mating pair can be repaired this way.
You may be able to roll or otherwise deform the material (knurl?) to avoid welding...
RE: pad welding cast iron fits
RE: pad welding cast iron fits
However, I have been in a pinch before and welded CI with Ni-Rod. The high preheat is required to prevent the cracking. I would recommend a 500 - 600F preheat. At my company, we would use tracing and wraps to maintain it during the weld process. If you start to lose the preheat, the cast iron will crack. After each pass, a person could choose to peen with ballpeen hammer to relieve stresses. We then slow cool it. Drop the tracing down to 250/300F and let cool. Then remove and cool in still air to ambient.
Another reason for the preheat and slow cool is to keep the welds soft. If you cool to fast and avoid the cracking, the part will be so hard that you can't machine it OR it can crack during machining process.
Cast iron welding is an art. There aren't many guys out there that can do it well. It takes lots of practice.
I hope that helps. I learned it the hard way!
RE: pad welding cast iron fits
RE: pad welding cast iron fits
Have you thought of machining a ring to shrink on the part to reclaim the fit? We have done that before in lieu of welding on the cast iron.
I have brazed locating pads but only on non critical components. The issue with brazing them is that you are not tying into the parent material. A braze can pop loose during machining or even worse during assembly.
RE: pad welding cast iron fits