Just because someone claims to be a so-called “certified” torch brazer does not mean that he/she will actually produce good-looking, leak-tight brazed joints in actual production situations. I have recently seen some very poor torch-brazing work done in a medical-supply facility by alleged certified torch brazers that caused me great concern and resulted in rejection of the torch-brazed system by the company.
By “poor work” I mean that most of the brazed joints looked ugly; were obviously done in a rushed manner; the insides of the pipes had not been properly purged to prevent extreme oxidation and contamination inside the medical gas-piping system; and the overall system lost too much pressure too quickly during pressure testing.
Let’s take a look at what a typical torch-brazing certification would require and how a properly completed brazed assembly would look.
By definition, a certified brazer implies that the individual has gone through a thorough torch-braze training program and then, based on both written exams and actual “performance” testing, that person will have proven that he/she knows how to braze and how to create a good-looking, leak-tight brazed joint.
There are a number of industry documents that can be used in various torch-brazing certification programs, such as those offered by the American Welding Society (AWS), the American Society of Mechanical Engineers (ASME), the American Society of Sanitary Engineers International (ASSE) and the National Inspection Testing and Certification Corporation (NITC), among others. These programs all assume that those doing the training are experienced, knowledgeable brazers with many years of actual hands-on experience who also have the ability to teach that to others.
My deep concern with many of these torch-braze training programs is that the trainers may not actually have the requisite skills in either their own hands-on experience or in their ability to teach what is required for conducting such a program. Torch-braze training should ONLY be taught by personnel who have many years of hands-on expertise in actual torch brazing of tubing/piping directly related to the industry he/she is serving, such as the HVAC (heating, ventilation and air conditioning) industry or the medical-piping industry, and should have the ability (and patience) to teach those skills to others.
Important Note: There is a big difference between welding and brazing, even though both processes can be used to join metals by using a torch, filler metal and heat. Just because an experienced welder has qualified as a CWI (Certified Welding Instructor), it does NOT mean that he/she is also qualified to teach torch brazing. Please understand that AWS does not make such claims and is very careful to state that CWIs are certified welding instructors only.
What I have occasionally seen in the field, however, is a good welder who thinks it also makes them capable of teaching brazing. That, in my experience, is a big mistake. I have actually had someone tell me something like this: “I am a good torch welder and trainer. Therefore, I should be able to teach torch brazing since welding and brazing are so similar.” That, unfortunately, is an incorrect and dangerous statement to make because, in reality, welding and brazing are VERY different. Welding tends to concentrate on external fillets, whereas brazing concentrates on the internal filling of a joint by molten BFM via capillary action. Brazing does not depend on, or need, large external fillets at all.
The ASME Boiler and Pressure Vessel Code (BPVC), Section IX covers the certification of welding, brazing and other fusion (joining) personnel. A picture of the cover of this spec is shown in Fig. 1.
The information for brazing that is found in Section IX of the ASME BPVC is modeled after AWS documents. My recent field observations of torch-brazed tubing/piping in a medical-processing facility caused me great concern about the training received by the brazers brought in from an outside brazing company when I personally inspected all the recently installed brazed tubing/piping in that medical-supply plant.
Many hundreds of joints and fittings had been brazed – yes, many hundreds of them – and they looked ugly, appeared to be produced in a rushed manner, displayed poorly made joints, were badly oxidized and even had a number of repaired fittings that had obviously been accidentally melted through and then re-brazed. Such a large amount of bad-looking joints really called into question the knowledge and experience of the so-called certified brazers who did the job as well as of their trainers.
Next time we will discuss the American Welding Society specification (AWS B2.2).