PISTON 3115 2126 00 / 3115212600 — Epiroc (Atlas Copco) Compatible

What the PISTON does

The percussion piston is the component that actually does the drilling. Hydraulic pressure drives it forward to strike the shank adapter, transferring an energy pulse down the drill string to the bit; the distributor then reverses it for the return stroke. Everything else in the drifter exists to feed, guide, seal or dampen this one moving mass.

Signs it needs replacing

• Loss of penetration rate with normal pressure and flow at the machine
• A change in the drifter's sound — a duller or irregular beat
• Visible bruising, pitting or chipping on the strike face
• Scoring along the sealing lands, which then destroys seals repeatedly

Before you fit it

A piston is never replaced alone. The bushings it runs in and the seals riding on it have worn to match its old surface, and reusing them puts a new piston straight back into a worn bore. Check the strike face of the shank adapter at the same time: a mushroomed shank end damages a new piston on its first shift.

General guidance for this class of component. Always work to the torque figures, clearances and service intervals in your machine's own manual.

About This Part