Komatsu D375A-8, Operation & Maintenance Manual

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SELECTION PROCEDURE OF RIPPER POINT
(Check for cracks
or breakage)
(Check penetration)
Procedure (4)
Procedure (2)
(Check wear)
Procedure (3)
Procedure (1)
Is wear fast ?
Are thermal
cracks produced ?
Does rock have high
quartz contents ?
Does it penetrate ?
(Can it be used to
end ?)
Do impact force
cause breakage ?
Do impact force
cause breakage ?
Does it penetrate ?
(Can it be used to
end ?)
Install standard point B
Yes
No
Yes No
Yes
(Over 70%)
No
(Less than 70%)
No Yes
No
Yes
No
Yes
Yes
No
Install point D
Install standard
point B
Install point F
Install point E
(Only type of point is worn) (Whole point is worn evenly)
Typical
rock
Hardness Soft Medium Soft Hard Soft Hard Soft Hard
Type of rock Shale, limestone
All type of general rock
Sandstone
Basalt, andesite, granite, chest
Features
½
f
Little quartz,
little wear
f
Deposited in
layers, so ripping
is easy
f
Proportion of
quartz is high
(70% - 90%),
point wears
rapidly
f
Proportion of quartz is not so high (40% - 70%)
f
Rock is not in layers or seams, so heat is generated
at point, point wear rapidly, ripping is difficult
Suitable
Features
Shape
Part No. 195-78-71420 195-78-71320 195-78-71370 195-78-71340 195-78-71350 195-78-71330 195-78-71390
Point B
f
Non-symmetrical
shape
f
Yellow
f
Short
Point C
f
Symmetrical
shape
f
Yellow
f
Short
Point D
f
Non-symmetrical
shape
f
Yellow
f
Long
Point E
f
Non-symmetrical
shape
f
Red
f
Long
Point F
f
Non-symmetrical
shape
f
Red
f
Short
Point G
f
Symmetrical
shape
f
Red
f
Short
Point A
f
Non-symmetrical
shape
f
Yellow
f
Short
SELECTION PROCEDURE OF RIPPER POINT ATTACHMENTS AND OPTIONS
6-4