Galvanizing

Hot Dip Galvanizing of Irregularly Shaped Articles (Ferrous Materials)

Scope:

This specification covers the Hot Dip Galvanized Coating on fabricated and unfabricated iron and  steel products. This specification does not apply to the continuous galvanizing process of chain link fence fabric, wire, sheet, and strip material.

Thickness requirements:

The average of five (5) readings shall be taken in three (3) locations, ends and middle of the piece being examined. The average of the five (5) readings shall not be less than the minimum for the class of material being tested. See table below.

Mass of Zinc Coating for Various Classes of Material

Classification of Material

Minimum mass of zinc coating g/m² (oz/ft²) Equivalent minimum thickness μm (mils)

1

Castings iron and steel

550 (1.80)

78 (3.00)

2

Rolled, drawn, pressed, or forged steel articles (except Classifications 3, 4 and 5 listed below)    
1 mm (0.039 in) and up to but not including 2 mm (0.078 in)

260 (0.85)

37 (1.44)

2 mm (0.078 in) and up to but not including 3 mm (0.118 in)

400 (1.31)

57 (2.22)

3 mm (0.118 in) and up to but not including 4 mm (0.157 in)

500 (1.64)

71 (2.77)

4 mm (0.157 in) and up to but not including 5 mm (0.196 in)

560 (1.84)

80 (3.13)

5 mm (0.196 in) thick and heavier

610 (2.00)

87 (3.40)

3

Screws, bolts, nuts, rivets, nails, and similar fasteners 10 mm (0.394 in) and under in diameterWashers under 5 mm (0.196 in) thick

260 (0.85)

37 (1.44)

4

Screws, bolts, nuts, rivets, nails, and similar fasteners 10 mm (0.394 in) and up to 12 mm (0.0472 in) diameterWashers 5 mm (0.196 in) to 6 mm (0.236 in) thick

300 (1.00)

42 (1.64)

5

Bolts, nuts, and threaded fasteners 12 mm (0.472 in) diameterWashers over 6 mm (0.236 in) thick

460 (1.50)

65 (2.54)

Notes:(1)    Based upon mathematical calculations 100g of zinc per m² of surface corresponds to a coating thickness of 14.3 μm (2 oz/ft² of zinc corresponds to a coating thickness of 3.4 mils)(2)    The mass of the coating in this standard is in terms of grams per square metre of surface area. In the continuous galvanizing sheet and strip industry, mass of coating is defined in terms of grams per square metre of sheet, both sides inclusive.(3)

 

 Galvanizing Requirements for Customer

 NOTE:  All material is side loaded and unloaded by forklift truck.The steel must be suitable for Galvanizing. Generally, Silicon should be <0.045, Phosphorus <0.04%, Manganese  <1.3% and Carbon <0.25%.

See ASTM A 385-section 3.2. Steels of different compositions may possibly be Galvanized with consultation.

All product Galvanized by Court Galvanizing will meet the requirements of CAN/CSA G 164 or ASTM 123 if requested PRIOR to Galvanizing.

Material must be suitably vented for Galvanizing with a minimum 3/8th inch diameter hole (See ASTM A 385) and be free from welding slag, paint, lacquers and/or grease pencil markings.

ASTM A 780 describes the procedures for touchup of Galvanized materials due to field welding or damage.