Overview; Design And Function; Working Principle Of A Rock Drill; Control Valve Mechanism - Atlas Copco 34WS-6 Prescriptions De Sécurité Et Instructions Pour L'opérateur

BBC 34WS-6, 34WS-8

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

Atlas Copco BBC 34 rock drills are suitable for
production drilling, raise driving and bolting in soft to
medium hard rock. No other use is permitted. The
piston diameter is large which gives high efficiency
even at low air pressure. The rock drills are water
flushed and designed to work on an air pressure of
6 bar. They are mounted on a feed, which consists
of a compressed-air cylinder. The cylinder is bolted
directly to the back head of the rock drill. There is a
brake ring on the upper end of the piston rod, which
prevents it from sliding out of the cylinder when the
rock drill is re-positioned. The rock drills are fitted
with a chuck bushing for 22 x 108 mm hexagonal
shanks. All machines are equipped with a 25 mm
connection for air and a 12.5 mm connection for
water.
To choose correct insertion tools, contact your local
Atlas Copco dealer.

Working principle of a rock drill

Impact Feed force
© 2015 Construction Tools PC AB | No. 9800 0829 71c | 2015-10-07
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
ratchet wheel rotation. The rotation is anti-clockwise
and is applied on the return stroke of the piston.
Flushing
Flushing is ducted through two concentric tubes, the
outer one for air and the inner one for water. This
means that flushing air is provided as soon as the
compressed air is switched on. The purpose is to
prevent water from entering the percussion
mechanism of the rock drill.
Return stroke
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