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Spiral Flute Taps

Spiral flute taps are mostly used for drilling blind holes in CNC machining centers. Spiral flute taps are divided into left-hand spiral flute taps, and right-hand spiral flute taps are mainly developed to solve deep hole thread tapping. The “deep hole” here refers to a threaded hole with a depth-to-diameter ratio> 2. According to different working conditions, different spiral angles are used. The common ones are 15° and 42° right-handed.

The advantages of spiral flute taps:

  •  Long service life: Compared with ordinary straight fluted taps, the life span of spiral fluted taps can be increased by 30%~50%, and some up to 2 times. This is because the chips are quickly discharged along with the spiral flute tap during the tapping process and will not be blocked in the groove and will not be discharged. There are few chipping and breaking phenomena, which improve the service life.
  • High efficiency and low cost: For tapping metal threads in difficult-to-machine materials, such as tapping blind hole and cutting threads in stainless steel, structural alloy steel, and various non-ferrous metals, with spiral groove taps, only need to use one tap for processing, and does not need to use grouped taps for processing

  •   When tapping internal thread, there is no need to repeatedly advance and retract the tap to remove chips, which improves the tapping efficiency and saves the high-speed steel materials used to manufacture the taps, and reduce the cost.
  • Adequate cooling and lubrication conditions: Because metal chips can be automatically discharged along with the spiral flute, it is not easy to block, the cooling and lubricating needs during cutting are improved, and the heat generation of the cutting part of the tap is reduced. This also enhances the durability of the tap.
  •  Smooth cutting, easy to buckle, low roughness
  • Smooth cutting, easy to buckle, low roughness
  • Small torque: Due to the smooth chip removal, the chips are not blocked in the narrow chip flute, and the existence of the helix angle increases the actual work
  • Angle, so the torque is small, generally about 30% smaller than the straight flute tap.

Spiral flute taps application:

  •  Generally speaking, spiral fluted taps are almost the first choice for blind hole tapping of flexible and ductile materials with long chips (such as cutting threads in stainless steel). The primary consideration here refers to thread tapping of small and medium-size (≤M36).
  • Spiral flute taps are more suitable for processing non-through hole threads (also called blind holes), and the chips are discharged upward during processing. The tap’s actual cutting rake angle will increase as the helix angle increases due to the helix angle.
  •   Experience tells us: For processing materials with higher hardness, the helix angle should be smaller, generally around 30 degrees, to ensure its rigidity and help extend the tap’s life.
  • For processing non-ferrous metals such as copper, aluminum, magnesium, and zinc, which are not very hard materials, the helix angle should be more extensive, about 45 degrees, and the cutting is sharper suitable chip removal.