Dipping Operations - Tempering & Hardening

Tempering and hardening metals adds to their durability and is accomplished in a three-step process:

• Heating the metal or alloy to a certain temperature
• Holding the metal or alloy metal at that certain temperature for a duration of time
• Quickly cooling the metal or alloy

OSHA regulates tempering and hardening processes for dip tanks with requirements, as follow:

• Dip tanks must be located as far as practicable from furnaces.
• Dip tanks must be located on noncombustible flooring.
• Dip tanks must have noncombustible hoods and vents (or equivalent devices) for venting to the outside. For this purpose, vent ducts must be treated as flues and kept away from combustible materials, particularly roofs.
• Each tank must be equipped with an alarm that will sound if the temperature of the liquid comes within 50°F of its flashpoint.
• When practicable, each tank must have a limit switch to shut down the conveyor supplying work to the tank.
• If the temperature of the liquid can exceed the alarm set point, the tank must be equipped with a circulating cooling system.

To learn more about Dipping, Coating & Cleaning Operations visit our Dipping, Coating & Cleaning Operations Online Training web page.