AMI 307 Weld Head Calibration Problem

Date 05-13-2008 11:34

We have an AMI 307 orbital welding system with an 8-4000 weld head.

For some reason, the speed calibration freaked out + it was going two orbits. I ran auto calibrate, and it went back to 1 orbit, but the speed is off. Now it appears the only way to get it back to "normal" is to run it timed with a stopwatch and adjust a trim pot.

Anyone else have similar problems? How often should this system be "calibrated"? I would not expect it to "drift" or change. We have about 60 weld procedures that I don't want to keep requalifying. The operator also scrapped a $2000 part when he did not know it was out of calibration. It could be one of those freaky Windows OS problems too. It has done that in the past, and the problems went away as mysteriously as they dissappeared. The system is only a year or two old. Anyone else with this system, be warned.

By TheSavvy1 (**)

Date 05-14-2008 04:15

I am familiar with the 207 power supply. I have had a similar issues with the 9-500 weld head. Once it was fixable by simply adjusting the trim pot. The other time it would not work by adjusting it so I replaced the trim pot and it did the trick. (I think that that trim pot lasted about 4 years)

I don't know if you have another weld head to try on your power supply, but it is always good to just try another so the power supply is not suspect.

As far as the calibration goes..

I do a calibration at every start up. As long as you do not power off your machine you should not need to do any additional calibration. It is always good practice to run coupon test welds every XXXX amount of welds, diameter/material composition changes, program schedule change or even after returning from any break. (I know some larger diameter assemblies take a long time so the redundancy cannot be expected on all applications)

Also keep in mind you can contact AMI as they are always updating software for these power supplies. It could be another place to start.

Anyhow I hope this helps/ you may already know all of this???

By OBEWAN

Date 05-14-2008 11:53

We run a macro coupon for every part start up, and then at mid shift, so we would catch a problem, but they would call me to adjust the weld process if it is out.

Yes, I know about the trim pot. I have a hard time using it because I don't have a stop watch. My wrist watch is +/- 1 secs off at best. I use a 1 inch diameter for a 15 sec rotation to time it to 4 ipm. I also run the auto calibrate routine. I am not sure which is better. Our welding engineer at our New York plant has the same system and he says that manual calibration is the only thing that would work for him.

I am waiting for a reply from the AMI engineer in California. The two orbit thing was a computer brain fart for sure.

By TheSavvy1 (**)

Date 05-14-2008 22:42

We have never used the stop watch to calibrate our machines, we have always used the auto calibrate mode.

If you ask for Brett at AMI in California he is great reference for these types of situations. He can usually coach you through it over the phone.

Or they also offer local seminars to get you or your techs more familiar with the power supply you have.

I believe if you send your tech to California it is free and they have these monthly.

Or they will charge you $1,000 plus per diem to fly their guy out to train your whole crew at your own facility.