TOS Trenčín SN Lathe Clutch Adjustment

Adjusting the clutch on TOS Trenčín SN32, SN40, SN45, SN50, SN55, SN63 and SN71. The same principle applies also to SUI32, SUI40 and SUI50 as well ass to SN400, SN500, SN630 and SN710.

The A and B multi-plate clutches are accessible after removing the cover on the rear side of the speed gearbox. When looking into the opening, the A clutch, which is activated when the working feeds are engaged, is located on the left side. The B clutch, which is activated when reverse operation is engaged, is located on the right side.

The clutches are factory-adjusted by the manufacturer and therefore should not be adjusted without a serious reason.

If one of the clutches needs to be adjusted, tighten the thrust nut (1). The nut is secured by a screw (2). Rotating the nut by 15° reduces the clutch clearance by 0.083 mm.

The clutches must be adjusted so that they do not slip when engaged, do not drive the spindle when disengaged, and do not overheat.

It is prohibited to reduce spindle speed by intentionally adjusting the clutch to slip. Only a slipping clutch should be adjusted.

The multi-plate clutches are a source of heat, generated by friction between the plates. This heat is transferred to the oil. If the oil temperature rises excessively — by 40 °C or more above ambient temperature — the speed gearbox must also be checked for correct clearance of the multi-plate clutches and the brake.

Notice:

Start with clutch adjustment only after the machine is cool.

Adjust only a slipping clutch.

For the correct identification of replacement parts for the clutch, see our article about friction discs replacement.