Question

Difference between gang drilling and multiple spindle drilling

Answer 1

A gang drilling machine consists of numerous individual columns, drilling heads and spindles that are mounted on as single base and use a common table. It is possible for various numbers of spindles to be used but commonly 4 or 6 are used.

On the other hand, 

Multiple spindle drilling machines are mostly used in economic mass production. Two different layouts are in use, vertical which is mostly prefered or horizontal multiple spindle drilling machine. In multiple spindle drilling, the spindles are positioned in such a way that they are unyielding/stiff.   

Answer 2

A gang-drilling machine:

A gang-drilling machine has many individual columns, drilling heads, and spindles that are set up on a single base making effective use of a common table. 

There can be any number of spindles, but it usually range from 4 to 6. 

This is developed for operating machine parts requiring several hole-machining operations, such as drilling, counter-boring, countersinking or tapping. 

Sequential machining operations are done by one or more operators by moving the work piece from one drilling spindle to the next.

Multiple spindle drilling machine:

It is used to drill a number of holes. 

It can be used to drill in different layout that can even be large and unsymmetrical. 

The drill head is set up on the drilling machine table. The drill head spindle is inserted in to the machine spindle.