Spring Pivot Bolt

Description

A subcontractor to the Aircraft Industry was looking for a solution to eliminate the manual deburring of the backward bore edge of a main bore by replacing it by a more efficient process. Its intention was to be able to machine the spring pivot bolt completely in one setup.

Application details

Application details

The bore edge to be deburred is marked by a red circle. The challenges of this bore were the steeply inclined bore edge due to the diameter ratio and the proximity of the bore exit to the wall.

  • Bore Ø4+0.03 mm exiting in groove/oblong hole Ø4.1 mm
  • Material: stainless steel / 1,4301
  • Machine: Gildemeister Langdreher G20
  • Machining: Horizontally
  • Cooling: Coolant Oil
  • Volume: 400'000 bores/year

Proposed solution

Proposed solution

These demands cannot be met by using a standard tool. For this reason HEULE designed a customer-specific tool based on the COFA C3-X tool (C3-X Ø3.8 mm). As a blade, an only-backward-cutting blade with a free angle of 30° (C3X-M-0001-X) has been selected.

Machining parameters:

  • Speed: N = 800 rev./min.
  • Feed: Fz = 0.03 mm
  • Life time blade: approx. 9500 bores/blade (at present)

Customer benefits

Customer benefits

The new setup allows a fully automatic machining of the workpiece including deburring.

Customer satisfaction

Customer satisfaction

The deburring is complete and clean. The life time achieved so far is satisfactory. In order to explore the maximal possible life time, further tests will be carried out.