There are many types of welding jobs and each job requires a certificate of qualification. This certificate of qualification proves that a welder is qualified to do a certain welding job, he has the skills required to perform the job satisfactorily and he is licensed to do the welding job. Every area of welding has a certificate of qualification. Welding qualification tests are done by recognized and authorized welding organizations. The tests are done in two parts. The first part is the written exam and the second part is an actual welding demonstration.
One example of a recognized and authorized welding organization that administers welding qualification exams is the American Welding Society. The exams are in two parts. The actual welding demonstration part is made difficult and challenging through time constraints and situations. The welds are checked thoroughly and sometimes with the aid of x-ray, measured force required to break the weld and pressure testing.
Some companies require welding qualifications for welder/fabricator positions. These companies usually do both the designing and welding/manufacturing the product. For pipeline welding, qualification tests are based on the capability to produce a weld that can resist bursting under pressure or breaking from bending or vibration. To test the weld, x-ray is used to make sure that the weld does not have gaps, hollow spots and other flaws that can weaken the welded area. Welder qualification exams for vertical welding, upside down welding and underwater welding are given only to more experienced welders.