Spaenaur

Inch
Pouces
Tap Terminology
Terminologie de taraud
Machine Taps
Taraud à machine
CATALOG 13
SURFACE TREATMENT
When choosing lubricant and type of tap to suit a particular application, the life of the tap can be further
prolonged by selecting the correct surface treatment.
1. BRIGHT FINISH (BF) - SPAENAUR carries Bright Finish in stock.
This is a ground finish without any further surface treatment. Used mainly for non-ferrous metals or
steels which do not cold weld.
2. STEAM TEMPERED (ST)
This is an oxide treatment which is recognizable by its deep blue/black finish. This treatment produces
tiny pitmarks on the surface of the tap, too small to be seen with the naked eye. These indentations
help to capture and retain the lubricant, thus reducing torque and discouraging cold welding. Used in a
wide variety of applications where build-up can cause problems, e.g. mild steel and all highly alloyed
ferrous materials, including stainless steels. Machine taps are supplied with a Steam Tempered finish,
unless an alternative is specified.
The following taps are available upon request, price on application:
3. NITRIDED (NI)
This treatment hardens the surface of the tool and gives it a mottled grey/black finish. This extra skin
hardness gives better tool life in the more abrasive shorter-chipping materials such as cast iron and
certain types of bronze, high Si aluminum alloys and plastic. This treatment can cause brittleness and
should be used with care.
4. DOUBLE TREATMENT (DT)
This combination of Steam Tempering and Nitriding is used mainly for nut taps and taps for special
application where the qualities of abrasion resistance and lubrication adherence are most beneficial.
5. TITANIUM CARBIDE NITRIDE (TIN)
A Physical Vapour Deposition (PVD) process imparting a shiny golden finish to the tool surface.
Features are high surfaces hardness (equivalent to Rc80-85)with good abrasion resistance allowing for
prolonged tool life. A low coefficient of friction results in reduced torque, temperature and cold welding,
thus allowing for greater tool speeds.
6. TITANIUM CARBIDE NITRIDE (TICN)
Another PVD process imparting a harder surface than TIN. Suitable for abrasive applications and for
high tensile materials.
P
Tel: 1-800-265-8772 Fax: 519-744-0818
P79
11 Apr 02