Saturday, May 26, 2012

Job Estimating

My name is Matt W. and I am a Manufacturing Engineer located in South Bend, Indiana.  I am looking for some insight on the best approach to quoting weldments. (best practices and industry standards).  I was hoping there might be a peer to peer group, or some related articles that I can access, to understand all of variables that go into quoting weldments.  There seems to be a great deal of information about deposition rates and travel speeds (linear equations) but not a lot about the additional variables like clamping, part handling, cleaning, grinding, packaging, etc.  This is what I am most interested in finding  more about.  Any information you can give me is greatly appreciated.

Matt W.

Hi Matt,
I use a program that is simply an Excel spread sheet developed by a company called Sterling.  The screen shots I’m attaching will give more contact info.  For me, this has worked great.
There are some general rules of thumb that you need to develop, such as Cycle Time or Arc-On time.  Here are mine:
·         20% arc-on time – This would be a typical manual work cell that assembles, tacks and finish welds parts.
·         40% arc-on time – This would be a typical manual work cell that receives a tacked assembly and finish welds it.
·         60% arc-on time – This would be a manual work cell where the welder rarely moves, doesn’t add parts and is continuously welding.  –or-  This is a robotic work cell that welds many short (<4”) welds, lots of arm movement, lots of touch sensing.
·         80% arc-on time – This is a robotic/automated work cell that completes continuous or multi-pass welds, does little touch sensing.
Those are important rules.  Get those wrong and you’ll never make money… and that’s why we’re here, to make money and keep folks employed.

There are many Weld Calculators out there.  This one works for me.
I had an employer that would calculate weld cost by simply knowing the inches of weld on a weldment.  They were very accurate, but a system like that would take years to develop… and theirs did.

My advice, find yourself a Weld Calculator that you are comfortable with and use that.  I’m not big on re-inventing the wheel.

Good Luck!

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