We first have to ask, what is Certified Welding? Certified Welding or a Certified Welder is a person that has taken and passed a series of steps or requirements with an employer and a third-party accredited weld test agency that is verified and accepted to the current welding and repair codes that are followed. The term “Certified Welder,” on the other hand, usually refers to a specific, organized, accredited third-party welding certification.
One common certification is the Certified Welder (CW) program offered by the American Welding Society (AWS) and or the ASME (American Society of Mechanical Engineers). If someone is a “Certified Welder,” this most commonly means they have taken and passed a third-party accredited test that is verified and accepted across the welding industry, but most Welding Certificates are not transferable from company-to-company unless they are enrolled in a Common Arc Program with other companies.
Welding certification can be misunderstood in the industry
Before becoming certified in welding, an individual will need to be familiar with:
- Fundamentals of Welding
- Understanding Welding Symbols
- The Types of Welding
- Materials in Welding
- Types of Weld Joints
- Welding Procedures
- Welding Safety
- Welding Equipment
- How to Perform a Sound Weld
Fundamentals of Welding
Welding is the process of joining two metal objects together by using a form of heat and a joining/filler material. There are some fundamentals that go along with this joining process, such as fusion zone, heat-affected zones, and so on. Welding provides a permanent joint. The welded parts become a single entity.
Understanding of Welding Symbols & Types of Weld Joints
Weld Symbols are basically like a legend on a map. Welding Symbols should be provided to inform the welder of what type of weld specification, procedure, where the weld is to be located and other information of joint or process.
The Types of Welding
1) Gas Metal Arc Welding ( GMAW/ MIG – Wire )
2) Flux Cored Arc Welding ( FCAW – Wire )
3) Gas Tungsten Arc Welding ( GTAW – TIG )
4) Shielded Metal Arc Welding ( SMAW – Stick )
In the boiler repair field there is mostly SMAW – Stick Welding, which is the most popular with GTAW – Tig Welding in a very close second. In each type of welding, there is different equipment, preparation, and technique that is used.
Along with Welding types, there are many different types of filler material/metal that could be used. Each filler material can produce different results when welded. For example Carbon Steel 6010 cover pass vs. Carbon Steel 7018 cover pass (see below).
Materials of Welding
When performing any welding you must know the material you are working with. When any repairs, new builds or even the sale of a boiler, you really need to know the material. The material will need to ASME acceptable along with a Material Test Report – which is like a birth certificate of the material, and I cannot stress enough how important record retention is for the material. When it comes to weld testing an individual, we have that information on hand and ready for the testing agency. Some of the weld testing coupons will look like this image to the right.
Once an individual has a good understanding of welding, a certified test can be started. There are different positions where any weld test can be performed, it all depends on the requirements and weld procedure set by the Quality Control Manager, Weld Engineer, and the Employer that is needed.
The horizontal rolled position. In this position the pipe is horizontal and it is being rolled so that you, the welder, are actually in a flat position relative to the pipe. It’s the easiest pipe welding position.
The vertical position. The 2G position is where the pipe you are welding is vertical and you are welding in the horizontal
The horizontal fixed position 5G is a lot like 1G in that the pipe is in the horizontal position. The difference is that the pipe is stationary and not rolling as you weld, which makes it more challenging.
Pipe inclined fixed position 6G is the most difficult of the pipe welding positions because the pipe is at a 45 degree angle and it is not rolling. Therefore you will need to be able to weld on all four positions to finish the 6G weld.
During the test, Weld Supervisors will be documenting variables which are a number of things such as welding machine volts, amps, DC or AC , was pre or post-heat used, interpass temperatures, time and internal notes. These notes are instrumental in the paperwork and record retention that needs to be associated in the testing of the test coupon piece and the individual performing the test.
The Test Coupon is then visually examined by the Weld Supervisor, and marked with an identifying number and name of the welder. The Test Coupon then goes to a facility that is accredited and certified by the AMSE or AWS, where different types of testing can be performed on the Test Coupon. The different types of test include: mechanical bend tests, radiography ( X-Ray) and so on from The ASME Section IX.
So what does it mean to have a procedure to be a Certified Welder, Welding certification means Certification in writing that a welder has produced welds meeting prescribed standards. It also means that the weld was performed by using a welding procedure specification (WPS). Welding certification almost always involves complying with a welding code or standard of some kind. The Certified Welder now also needs to document when they have welded that process type, procedure, and job number to maintain records showing that weld activity every 6 months to keep their weld certification valid.
PBBS’ experienced service and welding technicians hold all the necessary Certifications to perform boiler and related equipment repairs and modifications including the ASME S-Stamp, ASME U-Stamp and the National Board of Pressure Vessel inspectors R-Stamp. These guidelines are critical to follow for the integrity of the equipment and the safety of your personnel.
Source: Chad Bartkowiak, Quality Control Manager & Service, PBBS Equipment