What is the standard steps to apply welding procedures specification WPS. & what is the diffrence between WPS and procedures qualification recordPRQ?

WPS is a way to maintain the quality of welding if it is strictly follow. initial step of making wps is first pwps( preliminary welding procedure specification), second Test piece third Ndt fourth WPQR ( it is an accurate measurement of report commence in lab) and finally WPS which is tolerance report taken by WPQR.

Differences- AS i mention above please read at once. wps is taken by wpqr aps is approcimation of wpqr and PRQ is theoritical record of testweld performed and tested to ensure that procedure will produce a good weld