Materials


There are 4 types of carbon steel commonly used in the hollow metal door and frame industry:

  • Cold rolled steel: Not corrosion resistant. Must be protected with rust inhibitive primer.

  • Galvanized steel: Cold rolled steel with a zinc coating, for corrosion resistance. Should be factory primed.

  • Galvannealed steel: Heat treated hot dipped galvanized steel with a zinc-iron coating (A designation). Suitable for immediate painting after normal cleaning.

  • Stainless steel: Contains more chromium and nickel which offer high corrosion resistance.



de La Fontaine Industries does not use cold rolled steel. Since the primer on cold rolled steel hollow metal doors and frames can be scratched easily at the jobsite, this leaves the substrate steel without corrosion protection. Our standard material is hot dipped galvanized steel which offers better corrosion resistance than primed cold rolled steel. This means a longer life-time for the door opening and less maintenance for the end user.



Recycled content:

The galvannealed steel from our supplier is made of approximately 58% of recycled steel. The post consumer content is 20% and the post industrial content is 25%. The balance of 13% is comprised of home scrap which is internally generated scrap from the steel processing operations.

The stainless steel from our supplier is made of approximately 80% of recycled content.  The post consumer content is 20% and the post industrial content is 50%.  The balance of 10% is comprised of home scrap.




References:

ASTM A 240:  Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip for Pressure Vessels and for General Applications.
ASTM A 653:  Standard Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot Dipped Process.
NAAMM/HMMA 802: Manufacturing of Hollow Metal Doors and Frames
ISSF: International Stainless Steel Forum
SRI: Steel Recycling Institute
NAS: North American Stainless
ArcelorMittal Dofasco



Products & Solutions:




A 40 Galvannealed
Hot dipped galvanized steel, with a zinc-iron alloy coating.

Info: 0.40 ounce of zinc per square foot, total on both sides of metal sheet.
Recommended application: Interior openings.
Benefit: Corrosion resistance for masonry wall applications.
Limitation: Not recommended for exterior openings.
Comment: Suitable for immediate painting after normal cleaning.

A 60 Galvannealed
Hot dipped galvanized steel, with a zinc-iron alloy coating.

Info: 0.60 ounce of zinc per square foot, total on both sides of metal sheet.
Recommended applications: Exterior or wet areas.
Benefit: Corrosion resistance for exterior applications.
Limitation: None
Comments: Suitable for immediate painting after normal cleaning. Slightly more expensive than A40 galvannealed steel.

G 90 Galvanized
Hot dipped galvanized steel, with a zinc coating.

Info: 0.90 ounce of zinc per square foot, total on both sides of metal sheet.
Recommended applications: Exterior openings near the ocean, highly corrosive environments.
Benefit: Very good corrosion resistance.
Limitation: Not immediately suitable for paint. Must be coated with a special primer.
Comments: Spangled effect on steel. More expensive than A60 galvannealed steel.

Stainless Steel 304
Stainless steel, type 304, finish # 4 (satin finish).

Info: Made of 18% chromium and 10% nickel.
Recommended applications: Clean rooms (sterile), food processing installations, chemical plants, subways, esthetics.
Benefit: High corrosion resistance.
Limitation: Longer lead time required (4-5 weeks).
Comment: 8 times the price of  A 40 galvannealed steel.

Stainless Steel 316
Stainless steel, type 316, finish # 4 (satin finish).
Info: Made of 17% chromium and 12% nickel.
Recommended applications: Pool areas, water treatment facilities.
Benefit: Maximum corrosion resistance.
Limitation: Longer lead time required (4-5 weeks).
Comment: 9 times the price of  A 40 galvannealed steel.
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