Screw Thread Insert (STI) Spiral Flute Taps
Screw Thread Insert taps produce an oversize threaded hole to accept an insert with standard size threads.
- Provides greater lifting action, especially when tapping deep blind holes in ductile materials
- A built-in higher hook provides excellent shearing action
Spiral Flute Screw Thread Insert (STI) taps produce an oversize threaded hole that will accommodate a precision formed screw thread coil of a standard diameter and pitch. Spiral flute taps provide lifting action to remove chips in blind holes. These taps are identified as the size of the internal thread dimensions of the threaded insert.
A tap drill chart for these oversize taps is found under Service and Support.