Process: How to make an incandescent light bulb

How to make an incandescent light bulb

In this essay I will describe how an incandescent light bulb is made. All incandescent light bulbs have the three basic parts, the filament, the bulb and the base.

Bulb

Filament

Base

The filament is manufactured through a process known as drawing, in which tungsten is mixed with a binder material and pulled through a die into a fine wire. Next, the wire is wound around a metal bar called a mandrel in order to mold it into its proper coiled shape, and then it is heated in a process known as annealing. The coiled filament is attached to the lead-in wires. The lead-in wires have hooks at their ends which are either pressed over the end of the filament or, in larger bulbs, spot-welded.

The glass bulbs or casings are produced using a ribbon machine. The glass bulbs are blown by a ribbon machine. The base of the bulb is also constructed using molds. It is made with indentations in the shape of a screw so that it can easily fit into the socket of a light fixture. After the filament and stem assembly are inserted into the bulb, the air inside the bulb is evacuated and an argon/nitrogen mixture is pumped in. Finally, the base is sealed on.

As I have described, there three main parts of an incandescent light bulb. Each part are made separately and then assembled. Virtually the entire light bulb manufacturing process is automated.

By:

A. Darul Radzuan Hj Othman. (Group 2)