During this webinar, we review what is necessary to ensure a high-quality welding process during industrial capital projects.
Learning objectives include:
- Pre-Contract & Pre-Mobilization
- Basic Welding Processes
- Codes Governing PQR, WPS, and WPQ
- Documents for Pre-Mobilization
- Typical Inspections
- Tracking and Recording (i.e., Maps, Logs, Reports)
- Contractor In-Process Oversight
During the pre-contract stage, it’s essential to set the expectations for the contract—the more information, the better. This information should include:
- A clear technical scope
- Relevant specifications and code references
- ITP and NDE requirements
- Final data book content
Once the PO has been issued and teams have been assembled, a kickoff meeting will commence notifying everyone of the requirements of the capital project. During this meeting, you must:
- Review the Request For Proposal (RFP).
- Establish the communication process and contact list.
- Review ITP and go over hold points.
- Establish what the reports will look like.
- Note how the Punchlist will be handled and the PSSR expectations.
Shielded Metal Arc Welding (SMAW)
This process, also known as stick welding, uses an arc between a covered electrode and a weld pool to join metals. SMAW is commonly used on carbon steel pipes and structural steel and takes a moderate skill level to be able to master. The stinger used in this process utilizes electrodes. Typical electrodes used include:
- E6010 (cellulose coated): No heated storage
- E7018 (Iron powder coated): Heated storage
- H4R (Diffusible Hydrogen): Four to eight hours in open air
- ASME Sec. II Part C for filler metal information
Positives:
- It is a simple process (only three components make this process work).
- The process is versatile.
- No gasses are required.
Negatives:
- Slag generation process
- Produces sparks
- Lower productivity value (the efficiency levels are low)
To learn more about this type of welding process with examples, explanations, and FAQs, watch this part of the webinar!
The GTAW process produces a weld with a non-consumable tungsten electrode. When this process, first known as Heli-Arc, was first designed in the early 1920s, helium was the main gas used as a shielding gas. This became problematic because helium is lighter than air, and it takes a lot of helium to shield in this process. Therefore, it was refined in the 1940s to have argon be used as the primary shielding gas.
This process is commonly used on stainless steel pipes and requires a high skill level for mastery.
Positives:
- Clean process
- Minimal sparking
- High-Quality
Negatives:
- Inert gas purge for SS
- Lower production
To learn more about this type of welding process with examples, explanations, and FAQs, watch this part of the webinar!
The most commonly used and highest productive welding processes are GMAW, also known as MIG, and FCAW. These are both processes in which a wire electrode and a shielding gas travel through a welding gun to the metal, forming an electric arc. This can be done with automatic or off-the-shelf semi-automatic equipment. The typical wires used for these processes are ER70S-6 and ER308Lsi. Both of these processes require a moderate skill level for mastery, meaning a new welder would need a few months to master them, while a TIG welder could learn them within a week. These processes are very common in fabrication shops, and they both have very high productivity rates.
Example pictures with explanation and FAQs
PQR
A Procedure Qualification Record (PQR) is a record of variables recorded during the welding of the test coupons that demonstrates sound welding. It also contains the test results of the tested specimens. Recorded variables normally fall within a small range of the actual variables that will be used in production welding. The codes that govern PQRs are ASME Section IX, API 1104 (Pipeline), and for structural bridge work or stainless structural steel, AWS D1.1, D1.5, and D1.6.
ASME IX covers procedure and performance qualifications for welding, brazing, and fuzing. It’s broken out into the following five articles:
- Article I: Welding General Requirements
- Article II: Welding Procedure Qualifications
- Article III: Welding Performance Qualifications
- Article IV: Welding Data
- Article V: Standard Welding Procedure Specifications
WPS
A Welding Procedure Specification (WPS) is a document provided to welders or welding operators to provide direction for making production welds to code requirements.
ASME IX has provided the requirements for welding procedures. If a welding procedure was done correctly, at minimum, these variables will be accurately assessed:
- PQR(s) referenced on WPS line up
- WPS references the Code of Construction (COC) (i.e., B31.3, B31.4)
- QW-403: Base material and thickness range qualifications match pipe specification/line list
- QW-404: Filler metal is correct
- QW-407: PWHT
To take a look at a matrix of variables to help note essential and nonessential variables for welding documentation, watch this part of the webinar!
WPQ
Each company is responsible for the qualification of its welders. This test shall be carried out under the full supervision and control of the organization. However, certain aspects can be subbed out. Successfully qualified welders (or welding operators) shall be issued a number/letter or symbol by the organization for identification purposes.
Essential variables for welder performance qualification include:
- QW-402: Deletion of backing
- QW-403: Change in material (P# bundle, thickness range)
- QW-404: Filler metal (F# bundle)
- QW-405: Position (vertical up or down)
When you are getting ready to begin a job, there is some basic documentation that is required:
The inspectors will thoroughly go through:
- WPS reviews
- WPQ reviews
- Welder Continuity Logs
- Code of Construction (COC)
Most inspections are based on the Code of Construction and can also be based on client requirements. All of these should be clearly defined prior to the inspection in the inspection test plan. An inspection test plan shows what inspections and tests need to take place for any given process being used. Most of the time, a Visual Test (VT) of the final weld is required by the code; this is usually the only code-required visual inspection (except for closure welds for B31.3). Radiographic Testing (RT) or Ultrasonic Testing (UT) inspections are required based on the COC. B31.3 Table 341.3.2 is based on the product in the line. It’s important to note that B31.4 figure 434.8.6.2 will send you back to API 1104, and the requirements of the inspection are based on hoop stress and the location of the site.
These documents will include information to show that the system is sound and the weld is mechanically complete. The required tracking and records will vary depending on the project and client, but the minimum requirements will include a weld map, weld log, NDE report, and hydrotest report.
Weld Map:
- Identifies what welds were done and who welded them
- Identified unique weld numbers on isometrics
Weld Log:
NDE Report:
- Identifies that NDE reports were completed per the code
- Identifies that NDE reports were graded per the code
Hydrotest Report:
- Identifies the system boundary limits
- Identifies the Test Pressure and the medium used
- Identifies the calibration certificates
Contractor oversight uses these reports and audits to help mitigate problems on any particular project.
Site Audits (By Discipline) Based on QMS are used to make sure the infrastructure in question has been correctly built.
Contractor Reports are used to understand what is going on out in the field.
- Daily (require clear details)
- Weekly
Weekly Quality Walks are used to verify the quality of work.
Project Completion Audits are used to determine the level of completion done on a project. During the project kick-off meeting, it’s important to determine the expectations for these audits.
H+M Industrial EPC: Providing The Best Welding in Industrial Applications
At H+M Industrial EPC, we provide top-quality welding services for capital projects. With more than 35 years of providing leading capital project execution services to the energy, chemical, and terminal and logistics industries, we have the ability to create sound welding solutions for your project’s needs. For more information and to learn more about how contractors close out projects, watch our full webinar here!
Are you ready to get started on your capital project? Contact us today!
