Hollow Metal Door

Since the 1940s, technology has significantly improved the manufacturing process of commercial hollow metal doors. The manufacturing process involves nine steps before a metal door is shipped to a job site for installation. First, the process begins with the raw materials. The standard material for a commercial metal door is galvanized steel.

Galvanized steel is a steel surface that has received a galvanized coating, which has been annealed. Galvannealed steel starts with a galvanized coating, where the steel is dipped in zinc to protect it from rust. After coating, the steel is heated (annealed) to allow the zinc to bond with the surface. The result is a corrosion-resistant matte finish that holds paint well.

Steel shaping for commercial doors involves several key steps:

• Large steel sheets are cut down to the required door size.

• The sheets are bent and formed into the outer shell of the door.

• Reinforcement channels are shaped and