Drilling a 0.228" Diameter Hole 1.1" Deep in 316 Stainless

The Problem:

A customer was drilling 0.228" diameter holes 1.1" inch deep in 316 stainless steel. The tool he was using was a TiCN coated cobalt drill which he was buying at a cost of $9.95 each. The drills were being run at 600 RPM and being fed at 1.8 IPM in a peck drill cycle.

Productivity and tool life were unsatisfactory. Each drill was lasting about 200 holes before having to be replaced.

The Solution:

We proposed an RTW Type H solid carbide coolant through drill at a cost of $75.00 each. This drill was run at 1,200 RPM in a straight drill cycle (no peck drilling) feeding at 3.6 IPM. One drill ran the entire lot of parts (2,000 holes), and was put back in the drawer for the next run of parts.

Total tooling cost was reduced from $99.50 to $75.00. More importantly, the customer reported an increase in productivity of 100% and was thrilled with the results.