International Harvester Company 15D-2 Operator's Manual page 7

DESCRIPTION
HYDRAULIC-OPERATED BULLDOZERS AND
BULLGRADERS
The major assemblies of the bulldozer and
bullgrader are the hydraulic cylinders, radia-
tor guard with integral oil tank, hydraulic pump
and valve, cylinder hose connections, blade,
push frame, controls and trunnion brackets.
The hydraulic system consists of the hydrau-
lic pump, oil strainer, control valve with con-
trol handle, oil tank, hydraulic cylinders and
hoses.
The hydraulic pump forces oil to the cylin-
ders on each side of the unit, for raising or
lowering the blade. The direction of the oil
flow for raising, holding, lowering and floating
the blade is controlled by the operating plunger
(located in the valve housing).
Pressure control is established at the hy-
draulic pump where a pressure relief valve is
located. This pressure relief valve is set at the
factory at a pressure of 1650 pounds per square
inch (at full throttle), and automatically by-
pas ses oil when that pr essure is reached.
Relief by-pass ports in each piston head
automatically eliminate momentary high pres-
sure caused by the piston reaching the end of
the cylinde r ,
MODEL DESIGNATION OF TRACTOR EQUIPMENT
15D-2
15G-2
15D-l
15D-3
15G-I
15G-3
Bulldozer - Direct Lift Hydraulic
Bullgrader - Direct Lift Hydraulic
Bulldoz er - Front C. C. U.
Bulldozer - Rear
C. C. U.
Bullgrader - Front C. C. U.
Bullgrader - Rear C. C.
u.
SPECIFICATIONS
Blade
Length •••..••.•
Height ..•••••.•
Height, including spillboard
Maximum lift .••..•..
Maximum drop, below ground level
Moldboard
Construction.
Models
15D-2
,
.
9' 11"
38"
44-3/4"
39-1/8"
14-1/2"
. . .
. .
. . .
.
. .
. .
.
. .
.
Box framed
Cutting Edge (rever sible)
Length • • • •
Width
Thickness
Material
. .'
.
End Bit (2)
Length
Width
Thickness
Material
SpeCifications subject to change without notice.
7' 0"
8"
3/4"
High carbon
steel
15-7/16"
8"
7/8"
High carbon
steel
Continued on next page.
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