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USER GUIDE
TAPS

Tap Surface Treatments and Coating Types

The high speed steels we use grant high wear resistance under high temperatures, which means with
and toughness. For machining certain materials, insufficient cooling, or high speeds ≥ 600m/min.
various surface treatments are an advantage. The TiAIN has a hardness of approx. 3,000 HV and
is temperature resistant up to approx. 800°. Color:
Steam Tempered (ST) Violet-grey coefficient of friction against steel : 0.4
The steam tempered is a Fe3O4 oxide coating
which reduces the friction between the tool Hardslick-COATING – Hardslick
and workpiece and prevents cold welding. Hardslick combines in a novel way the advantages of
an extremely hard, thermally stable TiAIN-coating with
Nitriding (NI) the sliding and lubricating properties of an outer WC/C
Recommended surface treatment for machining hard (Tungsten carbide/carbon) coating. The hardslick coating
wear/abrasive materials such as grey cast iron, aluminum has a hardness of approx. 3,000 HV and is temperature-
alloys with high silicon percentage (more than 10%). resistant up to approx. 800°.
Color: Violet-grey coefficient of friction against steel : 0.2
TiN Coating (TI)
The TiN coating has a hardness of approximately Tolerances According to DIN EN 22857
2,300 HV and is temperature resistant up to For taps with ISO metric threads. The following chart
approximately 600°C. This is an excellent golden gives a comparison between the new standard DIN
colored coating for general applications. EN 22857 and the withdrawn standard DIN 802
part 1. An important change is the re-classification
TiCN-COATING – TiCN from tap tolerance to tap application class.
TiCN takes place of TiN when the conditions require the Application Tolerance class Allotment of the
coating to have a different hardness and toughness. The class for to withdrawn tolerance zones
TiCN brings an advantage to machining very difficult steels taps to DIN standard DIN of the nut thread
or cutting interrupted bores. The TiCN-coating has a EN 22857 802 part 1 to be cut
hardness of approx. 3,000 HV, but is temperature-resistant class 1 ISO 1 4H 4H 5H - - -
up to approx. 400° only. That means TiCN needs excellent class 2 ISO 2 6H 5G 5G 6H - -
cooling for long service life. class 3 ISO 3 6G - - 6G 7H 8H
Color: Blue-grey coefficient of friction against steel : 0.4
- - 7G - - - 7G 8G
TiAIN-COATING – TiAIN A suitable transition period is to be expected.
This is a special coating for machining abrasive Codes for tolerance classes 7G/8G and <X> tolerance
materials such as: gray cast iron, alu-alloys with zones have yet to be standardized within DIN EN 22857,
silicon, fiber reinforced plastics, etc., or machining and the values from DIN 802 part will remain valid.

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