weld testing

huangyhg

weld testing
can someone give me a quick summary of different methods of weld testing and where there are recommended:
radiographic
ultrasonic
dye penetrant
have you looked any of these terms up in your favorite web browser?  i just tried it and got some pretty good results.
hg
i have looked them up in the aws code but wanted a little guidance from someone more familiar with the actual testing procedures.  
there are about a million different answers here, especially when considering the application, i.e structural, pipe, etc.
very basic breakdown of what i normally see in the power industry:
mt or lp on fillet welds, seal welds, attachments, etc, lp obviously getting the nod for non-magnetic materials.
rt on most of your critical, full pen welds, with ut being the alternative to rt when factors don't permit it to be performed successfully, such as joint configuration, geometric unsharpness levels, etc.  rarely will you see rt or ut being done voluntarily for time/cost reasons in the field.  
a code book is generally not intended for use as an instructional tool, so not the best place to start looking for background information.  a web search may or may not be a good way to get technical info, but it's good policy to try that first before asking other people for answers.
many of the welding consumable manufacturers (lincoln, esab, etc.) have educational materials on their sites.  this will turn up in a web search.
hg
my firm provides weld  testing for asme and  aws welded joints,most asme  welds on power/chemical process pipe are xrayed ,most structural joints cjp like beam to col, are ultrasound due to geometry.if you have a large project or very critical weld take my advice get a good welding inspector to monitor the entire weld fit-up to weld out. it's easier to fix as you go along than come behind and find rejects which require repair .