Overview; Design And Function; Working Principle Of A Rock Drill; Control Valve Mechanism - Atlas Copco BBC 34-DSI Prescriptions De Sécurité Et Instructions Pour L'opérateur

BBC 34-DSI

Overview

To reduce the risk of serious injury or death to
yourself or others, read the Safety instructions
section found on the previous pages of this
manual before operating the machine.

Design and function

BBC 34 DSI rock drill is air-flushed and is intended
for air pressures of 4–6 bar. The rock drill is designed
for the following operations:
BBC 34 DSI is specially adapted for the Dimensional
Stone Industry (DSI) and is intended for rig-mounting.
No other use is permitted.
It is a highly efficient rock drill suitable for medium
and hard rock formations. The long stroke and high
impact energy makes it ideal for hard rock. A large
piston diameter gives high efficiency even at low air
pressures. The rock drill has a powerful rifle bar

rotation mechanism.

The rock drill is equipped with a chuck bushing for a
22 mm x 108 mm (⅞ in. x 4¼ in.) hexagon shank, a
25 mm (1 in.) connection for air to the impact
mechanism and a 12.5 mm (½ in.) connection for
flushing air. The flushing system can be converted
from air to water flushing.
To choose correct insertion tools, contact your local
Atlas Copco dealer.

Working principle of a rock drill

Impact Feed force
© 2012 Atlas Copco Construction Tools AB | No. 9800 0678 71b | 2012-08-10
Original instructions
Rotation

Flushing

Safety and operating instructions

Control valve mechanism

The valve directs the air alternately from one side to
the other of the piston so that it moves up and down.
The piston transmits the energy through the drill steel
to the bottom of the hole.
Rotation mechanism
Impact stroke
The drill steel is turned slightly with each blow by the
rifle bar rotation. The rotation is anti-clockwise and
is applied on the return stroke of the piston.
Flushing
The flushing air is ducted through a tube which needs
to be separately supplied with flushing air from the
12.5 mm (½ in.) air inlet nipple in the backhead. If
needed the flushing system can be converted to
water flushing. If converted, flushing will be ducted
through two concentric tubes, the outer one for air
and the inner one for water.
Return stroke
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