Document Controller

Of cause not.

software has to match the goal set, in order that control them.

what type is your welding machine? how much heads?

How to trace the sleam of welding? optical (machine version) or infrared indicator? it has to be special software.

what ndt? UT or infrared, or eddy or x-ray?

What about an Excel spreadsheet?

The document control software could be the general database software that can be applied to monitor the issuing, revision, documentation comments and approval/comments schedule reminder, traceability, storage location, reminder for certificate validation/recalibration schedule etc. which are handy in controlling medium size (numbers) of documents for projects execution.
The weld traceability could cover the production joints, its inspection status like, fit-up, visual, NDT(RT, UT, MT, PT, ET, etc..) and Accept / rejection status, welder's register, welding procedure specification register and detail, welding process, material, PWHT, NDT status for a system (e.g. piping), etc.

Certainly not.

It can be a small parts of the whole system, as well as access etc. datebase.

it needs recongnize, feedback control, adjust etc serial action.

and ony auto evaluation is a very heavy task for the software. and there is still not yet a very gooo software for the function of ndt now. as I know.

Most of time it needs man to manupulate

but indeed there are many people dedicate to develop it.

if he wish to manage his collect data from all process in practice,

he can use either excel or fox pro or other large database etc. thats not complex.

Not really. In the world of doc control and documentation, a true doc control program is pretty specific - allowing check-in and check-out and keeping track of version and rev numbers. Most anyone that has produced this type of software had their eye on the prize (cost) in the first place.

On the other hand, let us know if you find anything!

Search for source code control.

Some are open source, therefore free.

This isn't free, but it may do what you want - http://www.filesphere.com/