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REAMING TITANIUM Reaming is not a very common operation in machining titanium; however, various processes
REAMING TITANIUM

require it. ISCAR’s line of reaming tools comprises several families of reamers. The families
differ in their design: a solid carbide concept or an assembled one. Reaming titanium features
a relatively large proportion of required non-standard dimensions for the nominal diameter
of a hole and its tolerance limits. It often is caused by “springiness” of titanium and this
characteristic should be considered during process planning. ISCAR provides tools for reaming
titanium at the customer’s request, as tailor-made products; the most suitable solutions are
customized high-speed reamers on the base of the BAYO T-REAM family (Fig. 35).

A typical BAYO T-REAM reamer (Fig. 36) is an assembled tool comprising a holder (also
referenced as a shank) and an interchangeable multi-flute reaming head, produced from
cemented carbide. The head is mounted in the holder with the use of a unique quick-change
bayonet mechanism. The heads feature different connection size (“bayonet number”) that
has designation BN5, BN6, …, BN9. Each size corresponds to a specific area within the
diameter range of the reamers. There are heads with different flute directions depending
on the type of a machined hole: through or blind (Fig. 37). The holder material is usually
steel but, if necessary, it may be also heavy metal and cemented carbide. The reamers are
suitable for inner coolant supply where the coolant flow is directed on every cutting edge.

Fig. 35 A BAYO T-REAM reamer

The design concept of the family offers the following advantages:
1. Versatility – the holder can carry different heads, and the head is suitable for mounting in different
holders. This feature ensures a wide usage of standard holders, diminishes needs for tailor-made
ones, and thus reduces tool stock.
2. "No setup time" principle – replacing a worn head by a new one does not require additional setup
operations and can be done when a reamer is clamped directly in the spindle of a machine tool.
It is an efficient means to cut the machine downtown and reduce production cost.
3. Easy-to-use – the head is replaced in a quick and simple way.

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