Designation of drill

In Indian standard system a drill is designated as follows:

For example: 

A parallel shank twist drill of long series, 10mm diameter, conforming to IS standard, made of carbon steel, of type S and point angle 80 is designated as:

Parallel shank twist drill (long) 10.00-IS : 599-CS- S- 80

Type

Drills are made in 3 different types namely:

Normal (N) with point angle 118⁰

Hard (H) and Soft (S)

Shank

Shank of the drill may be parallel shank or taper shank which generally depend on the size. Generally large size drills are made with taper shank and small sizes with straight shank.

Material of drill

Materials used for drills are :

Carbon Steel(CS)

High Speed Steel (HSS) and

Carbide tipped drills