7
6
R
ELIABILITY
F
EATURES
HYDRAULIC EXCAVATOR
PC850
-8
0
Strengthened Quarry Bucket Provides Outstanding Wear-resistance
The bucket for specific use in quarry is impact and wear resistant, providing high performance and long life.
Koma-hard materials* provide excellent wear resistance. Combined with adoption of long-life KMAX teeth, durability of bucket
is drastically enhanced.
* Koma-hard materials (KVX materials):
Komatsu developed, wear-resistant, reinforced materials.
Brinell hardness: 500 or more (180kgf/mm
2
class).
Features high wear-resistance and little quality change
from the heat generated during rock loading, maintaining
long term hardness.
Excellent Reliability and Durability
Boom Foot Hoses
The boom foot hoses are arranged
under the boom foot to reduce hose
bend during
operation,
extending hose
life and
improving
operator safety.
Metal Guard Rings
Metal guard rings protect all the
hydraulic cylinders and improve
reliability.
Sturdy guards
shield the travel motors
and piping against damage from rocks.
High-pressure In-line Filtration
The PC850-8 has the most extensive
filtration system available, providing
in-line filters as standard equipment.
An in-line filter in the outlet port of
each main hydraulic pump reduces
failures caused by contamination.
Track roller guard (full length)
Sturdy Undercarriage
The undercarriage is strengthened to
provide excellent reliability and
durability when working on rocky
ground or blasted rock.
Quarry Bucket with KMAX Tooth
High-tensile
strength steel
High-tensile
strength steel
High-tensile
strength steel
Shroud: Enlarged
High-tensile
strength steel
Koma-hard materials
High-tensile
strength steel
KMAX Tooth
• Unique bucket tooth shape, superior digging
performance
• Long-term high sharpness
• Great penetration performance
• Hammerless, safe, and easy tooth
replacement
(Tooth replacement time: Halves the
conventional machine.)
STEP 1
Observing proper safety procedures,
place tooth onto adapter (as shown).
STEP 2
Insert fastener, making sure it is in the
unlocked position (as shown).
STEP 3
Using the correct size socket, rotate the
pin locking shaft 90˚ clockwise (as
shown) to finish the installation.
STEP 4
To remove fastener, use the correct size
socket to rotate the pin locking shaft 90˚
counter-clockwise (as shown). Remove
fastener and tooth. Repeat steps 1-3 for
a new installation.
pin locking shaft
pin locking shaft
Heat-resistant Wiring
Heat-resistant wiring is utilized for the
engine electric circuit and other major
component circuit.
Circuit Breaker
With circuit breaker, the machine can
be easily restarted after repair.
DT-type Connectors
DT-type connectors seal tight and
have higher reliability.
Rock protectors
Photo may include optional equipment.
H
Y D R A U L I C
E
X C A V A T O R
PC850
-8
Metal guard ring
(Cast iron ring)
Piston ring
Wear ring
Strengthened Boom and Arm
Thanks to the large cross-sectional
structure employing a high tensile
strength steel with a thick plate,
partition wall, etc., the boom and arm
exhibit excellent durability and are
highly resistant to bending and
torsional stress.
Large cross sectional
structure boom
Arm dent
preventive plate
Partition
wall
Partition
wall
Wide width
arm
Wear plates
O-ring Face Seal
The hydraulic hose seal method has
been changed from a conventional
taper seal to an O-ring seal. This
provides improved sealing
performance during operation.
Frame Structure
The revolving frame mount and center
frame mount on the swing circle are
no welding structure so that force is
transmitted directly to the thick plate of
the frame without passing through any
welding.
Fuel Pre-filter
(with Water
Separator)
Removes water
and contaminants
from fuel to
enhance the fuel
system reliability.
Strengthened Revolving Frame
Underguard
Guards the machine body against
being hit by rocks from below and
prevents hydraulic components and
the engine from being damaged.
