Welding Codes & Standards, Explained
HWF’s credentials refer to three industry standards: AWS D1.1, ASME Section IX and API RP 4G. Here is what each one is, in plain English, and what it means for your job.
American Welding Society (AWS)
AWS D1.1: Structural Welding Code – Steel
AWS D1.1 is the American Welding Society’s Structural Welding Code for steel. It sets the rules for welding structural carbon and low-alloy steel, and project specifications and contracts often call for it by name.
What it covers
- Design of welded connections
- Welding procedures: written procedures that are either prequalified by the code or proven by testing
- Welder qualification: welders pass hands-on tests before they weld to the code
- Fabrication and workmanship
- Inspection and the criteria a finished weld must meet to be accepted
- Repair and strengthening of existing steel structures
Why it matters to you
When work is done to D1.1, the procedure, the welder and the finished weld are all held to a published, widely recognized standard. You get consistent, documented quality on structural steel such as skids, base beams, stairways, platforms and derrick sections.
HWF and AWS D1.1
HWF is AWS D1.1 certified. Structural steel work, including derrick repair and modifications, is welded to AWS D1.1.
American Society of Mechanical Engineers (ASME)
ASME Section IX: Welding Qualifications
ASME Section IX is the ASME code for qualifying welding procedures and welders. It sets out how a welding procedure is proven by testing, and how a welder shows they can make sound welds with it, before production welding starts.
How it qualifies procedures and welders
- Welding Procedure Specification (WPS): the written instructions for making a particular weld.
- Procedure Qualification Record (PQR): the record of a test weld made to that procedure, with the test results that prove it works.
- Welder Performance Qualification (WPQ): the record showing a welder passed a qualification test, and which kinds of welds that welder is qualified to make.
HWF and ASME Section IX
HWF follows ASME Section IX code for welding procedures and welder qualification. If your job or spec calls for it, say so when you call, so it’s covered before work begins.
American Petroleum Institute (API)
API RP 4G: Drilling & Well Servicing Structures
The American Petroleum Institute (API) is the national trade association for the U.S. oil and natural gas industry. It publishes more than 800 standards and recommended practices used across the industry.
API RP 4G, Operation, Inspection, Maintenance, and Repair of Drilling and Well Servicing Structures, is API’s recommended practice for keeping rig structures safe and serviceable: masts, derricks, substructures and their accessories.
Inspection categories
RP 4G sets out four inspection categories. Categories I and II are routine checks: watching the structure in operation, and looking for corrosion, damage, loose or missing parts and visible cracks. Categories III and IV are the in-depth inspections:
Category III
A thorough visual inspection of all load-bearing components and members of the mast, derrick or substructure. The results are documented on a checklist and kept in the rig’s permanent file. For truck- or trailer-mounted well servicing masts, it includes watching rig-up and rig-down.
Category IV
Everything in a Category III, plus: the equipment is disassembled and cleaned as needed, critical joints and the welds in critical areas get nondestructive testing (such as magnetic particle, dye penetrant or ultrasonic testing), and every weld is visually examined. It is done or closely supervised by a Professional Engineer or the manufacturer’s authorized representative.
Repair and recertification
RP 4G also covers repairs to rig structures. Structural repairs are planned ahead and approved by the manufacturer or a qualified person, using approved welding procedures and replacement materials that meet the original manufacturer’s specifications or equivalent. Major damage should be repaired in a shop-like environment. RP 4G calls for welders on derrick and mast repairs to be certified to AWS D1.1 or equivalent.
HWF and API RP 4G
Robert follows API RP 4G for the repair and recertification of drilling and well servicing structures and rigs, including derricks, masts, substructures and base beams. Category III and IV inspections are performed in accordance with API RP 4G, and guided base beams are engineer certified in accordance with API RP 4G. All work is performed to adhere to API standards.
“…a wise man who built his house on the rock.”
AWS D1.1, ASME Section IX and API RP 4G are published by the American Welding Society, ASME and the American Petroleum Institute. HWF Welding & Fabrication is an independent shop and is not affiliated with or endorsed by these organizations. Have a specific code or spec requirement? Call (701) 570-7689 to discuss your job before work begins.
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