Page 693 - Yamawa_European_Catalogue_YEU21

16. Carbide Taps

Intro

Technological advances in CNC machines and machining centers, and machining automation have helped to improve the overall tapping
process. SP
YAMAWA was quick to answer to the evolving customer needs.
We have developed a wide range of carbide taps for tremendous improvements in mass-production and cost reduction. It is estimated that
carbide taps have 50 times more durability than HSS taps in tapping, when used properly. YAMAWA engineering believes the best carbide
materials suitable for taps are ultramicro-grain tungsten carbide, or ultrafine-grain carbide made of high cobalt.
SL
Features of Carbide Taps
(1) Excellent durability with high toughness is obtainable.
(2) High anti-friction features are provided by the material’s high hardness and comparatively high toughness, which ultimately results in a
longer tool life.
(3) Specially designed cutting angle and other dimensional features produce the internal threads with high tolerance accuracy and PO
consistency.
(4) Under certain tapping condition, YAMAWA carbide taps can be used even for tapping hard-to-machine materials.
Points to note during tapping with Carbide taps:
ST
(1) Machine vibration, or run-out, can lead to Carbide tap chipping and premature failure. Tapping vibrations need to be kept to a minimum.
(2) Tap holder should be a rigid type for a Carbide tap. A holder attachment with axial float, or radial float tends to promote Carbide tap
breakage and chipping.
(3) The hole to be tapped must be located correctly and on center; any centering off or non-straight drilled hole tends to cause Carbide tap
breakage due to deflection. Select correct hole depth with respect to tapping length (for blind hole only). It is especially important to ROLL
prevent tap damage from chip packing and bottom thrusting in blind hole tapping.
(4) Cutting lubricants - select grade of lubricant. Improper flow of coolant, or lack of sufficient amount of lubricant, or cooling can increase
the likelihood of Carbide tap chipping due to work material welding. Caution must be taken during dry machining to prevent chip
welding to the tap.
(5) Work pieces - we provide Carbide taps with increased toughness, but Carbide taps are inferior to High Speed Steel (HSS) in the area of CARBIDE
toughness. As a matter of fact Carbide taps have limited application due to this difference in toughness to HSS.

Commonly used materials and cutting conditions

Cutting Speed LONG
Work Materials Cutting Fluid (General recommendation)
(m/min)
Ordinary 15-25 Dry, light oil, water soluble oil
Cast Iron Nodular Graphite 10-20 Light oil, water soluble oil HAND
Malleable 10-20 Water soluble oil TAPS
Aluminum 20-40 Light oil, water soluble oil
Copper 15-30 Light oil, water soluble oil
Brass 20-30 Light oil, water soluble oil
Copper Alloy
Phosphor Bronze 15-30 Light oil, water soluble oil EG (STI)
Aluminum Alloy 15-25 Mixed oil of lard oil and kerosene
Die-Cast
Zinc Alloy 12-20 Mixed oil of lard oil and kerosene
Thermosetting 15-25 Water soluble oil, air SPECIAL
Plastic
Thermo Plastic 15-25 Water soluble oil, air THREADS,
Hard Rubber 15-30 Dry, air GAUGES
Note: The table shows only general conditions. As for actual cutting operation, please consider the following points: (1) Machine Capacity, (2) Work piece(s), (3) Work Shape, (4)
Setup (5) other factors.
THREAD
MILLS

DIES

CENTER
DRILLS

Technical
info

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