Is there another process besides destructive testing, which we perform, to check weld integrity? We currently cut "coupons" out of the tank at various sections that coincide with the weld program. We then pull them apart using a machine and look for voids at the weld. The company has been doing this for over 30 years. Thanks for any help.

-- Gary M Gubacz (ggubacz@ford.com), February 18, 2004

Answers

Water test (fill tank with pressurized air and submerse in water). Burst test (fill tank with lots of pressurized air until it bursts). Helium test (fill tank with helium and use mass spectrometer to detect leaks). Ultrasonic test (use an ultrasound transponder for detecting flaws). Eddy current test (use electrical inductance to detect flaws). X-Ray Tomography (use x-rays to look at your joints). 3-D X-Ray Tomography (use x-rays to build a 3-dimensional image of the joint interior and exterior)

You're a Ford welding engineer? If you are trying to improve the Police Cruiser tank, you need more help than you can get here, buddy.

-- April Fuhul (fuhul.april@balthisar.com), March 02, 2004.

Set up and maintain the best welding conditions to reduce the inspection need frequency: setup welding process controls such as constant current and servo wheel speed motor control that maintain the process within narrow limits; or setup welding process monitoring such as weld current inprocess monitoring or wheel speed monitoring that marks the part (for inspection) if process allowables are exceeded; establish good weld wheel maintenance such as high pressure water cleaning or some type of abrasive wheel cleaning with a rigidly maintained wheel change interval that maintains wheel diameter to a good control value; establish a method to insure a weld metal cleanliness level; establish good ISO process and receiving metal condition documentation; and good training for people around the process on how to follow the ISO documentation; setup needed PM on the welding equipment: weld cylinder rebuilds on a periodic basis, process requalifications (performance checks) quarterly. We did this in an entire plant, and the inspection frequency need dropped to a fraction of the historic rate; that is we eliminated the need for frequent inspection by putting the welding process into control and maintaining it on the center of all variables. If there is an interest, we'll talk more about this in an upcoming book in the near future. The right way of welding is a bigger job than many people do, but it is a lot less work than added inspection and repair when it is not done. Bob Szabo ww

-- bob szabo (bob@szabopublishing.com), April 26, 2004.