Last Friday we order some 40" OD Field Machining equipment to re-cut a tongue and groove in a 33" OD flange in Wichita Falls TX. We go to pick it up at Fed Ex Heavy on Monday and find out equipment is in Iowa. What the shit? We are due at the job site Tuesday AM.
We order another machine from Chicago and have it driven via hot shot to the job site. Due to the complexity of the machining required i solicit another machinist from our Long view TX location to help out my machinist. They call me Tuesday AM. The call goes something like this:
Machinist- you didn't look at this job before you bid it did you?
ME - No, it is a standard tongue and groove, what is the problem?
Machinist - the top flange is 33" OD (outside Diameter) and the bottom flange is 25" OD
Me - what the shit, how can that be, are you sure.....?
Machinist - did you send me here because I'm pretty or because i know what i am doing. We need a 30" machine so get it coming.
Me - I'll order it and i am on my way. You better hope i am not ordering another machine for no reason, butt plug
So i load up about noon on Tuesday and set out for Wichita Falls TX. I get there about 5 hours later and go straight to the job site. The machinist was right. Two different OD flanges bolted together. This was going to be a bitch of a job
A little background on a tongue and groove flange. One flange has a tongue machined onto it. This particular one was .512 thousandths thick and .250 thousandths tall. The receiving flange has a groove machined into it. this one was .562 wide and .187 deep. Our tolerance was plus or minus zero. Now it sounds simple enough but you must know that we could not locate center on either flange due to distortion of the flange and the receiving flange was welded on an 18" nozzle. We couldn't measure off the OD of the flanges because the chlorine had eaten the flanges to the point where there was a lot of pitting and we didn't know which was true. We had to establish reference points on both flanges and work the math backwards to make it right. Remember that when you set the top flange down, the tongue and groove have to match and the flange we could remove weighed about 500 pounds. A welder had spent Monday overlaying the flange with weld build up so we could machine the two flanges back to spec. Never a good sign.
Customer tells us that the Heat Treat guys will be there on Wednesday to Stress relieve the flanges. After that much welding, the flanges become brittle so they must be cooked about 6 hours at 1300 degrees to relieve the stress in the metal and eliminate premature fatigue of the metal.
We are machining the dollar plate when the 2nd machine arrives at 1900. I help one machinist set up on receiving flange and he starts cutting away. I was floating between the two helping out when needed. At about 0230 i notice that the thickness of the flanges doesn't match the engineering drawing and call the customer to inform him. He said keep going, we said OK. About 0630 we finished both flanges and turned them over to the customer for inspection. They performed a dye penetrate test and both flanges had indications in them. An indication is a point on the flange where the weld does not meet the code and must be cut out and re-welded. This is a common problem with non-automated overlaying.
The welder gets back at it and we wait for him to be done. When he is done we re-machine the flange to specs and do another PT test on it. We go through this process several times before the flanges pass inspection. (Note) the welder was damn good. He was trying to do what few people can do.
Around 1700 on Wednesday we dry fit the flanges and they mated well. We were done. We were on-site for 34 hours and tired. The customer was so happy that we worked it through that he took us out for Beer and steaks and let me tell you we put a hurt on his credit card. I got to bed about 2230 Wednesday and i was done.
Tuesday was my birthday so i spent it in a plant in Wichita Falls TX with two good friends doing what i love to do and eating cold pizza for supper. It definitely kept my mind off my personal issues for a couple of days. I must admit that i enjoyed my birthday this year.