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What is CSA G40.21 50W / 350W Class H?

pdf-image-25CSA G40.21 50W or Metric 350W Class H   pdf-image-25CSA Properties Chart

In accordance with CSA G40.21, hollow sections — welded or seamless round, square, rectangular or special-profile structural tubing — are available in two classes: Class C Hollow sections that are cold-formed from a section produced either by a seamless process or by an automatic electric-welding process producing a continuous weld. Class H (i) Hollow sections made by a seamless or furnace-butt welding (continuous welding) or automatic electric-welding process, and hot-formed to final shape; or (ii) Hollow sections made by a seamless automatic electric welding process producing a continuous weld, and cold-formed to final shape; subsequently stress-relieved by heating to a temperature of 450°C (850°F) or higher, followed by cooling in air.

CSA G40.21-2013 

Description: General requirements for rolled or welded structural quality steel.

Intended use: General specification for plates, shapes, hollow sections, sheet, sheet piling, cold-formed channels and bars used in construction.

What are the benefits of Class H? 

  • Increased axial capacity in accordance with CSA S16-14
  • Savings in mass up to 20%
  • Produced every 2 weeks in our Harrow Plant

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