SANY SRT95C Off-Highway Truck. Service Manual

changes in suspension cylinder ambient
temperature will change its nitrogen charge
volume and,consequently, its operating height.
It might be necessary, therefore, to add or
remove nitrogen to maintain proper cylinder
height as ambient temperature changes.

Filling oil

(Cylinder filled with oil initially, or

refilled with oil during maintenance)

Note

: This method is recommended to fill

oil when the loss of oil in the suspension
cylinder is caused by some other reasons but
surface leakage. If surface leakage occurs,
the cylinder should be removed and replaced.
Return the suspension cylinder to factory for
repair. Unauthorized repair may influence its
quality.
Oil level of the suspension cylinder mounted
on mining truck can be checked and adjusted
according to the following steps:

Note

1: During the operation of mining truck,

the charged nitrogen in the cylinder tends to
be mixed with oil. When the nitrogen pressure
is released, oil will be released from the
suspension cylinder in the form of foams.

Note

2: To detect oil level correctly, nitrogen

must be completely discharged from
the cylinder body. This operation can be
completed by evacuating gas or by sustaining
frame properly with cushion block to keep
cylinder. in the open state for more than 24
hours.This operation is required only when
surface leakage or deviation excessive.

Note

3: This procedure should be performed

after  the  suspension  cylinder  is  installed
on  mining  truck.  If  it  is  not  installed,  the
suspension cylinder should be placed with a
proper supporting form and fastness before
this procedure is operated.
1. Position the truck in a level work area. The
truck must be parked stably without applying
friction brake system.
2.  Jack  frame  up  until  front  suspension
cylinder  is  fully  extended. The  dimension

Front Axle Assembly

“A”(See Fig.8,distance between the center of
pin and end cap of guide sleeve) is equal to
525mm when the cylinder is fully extended.
Secure  front  suspension  cylinder  in  this
position.
3. Remove the cap from nitrogen charging
valve at the top of the cylinder. Turn the hex
out  on  the  valve  1/4  to  1/2  turn  counter-
clockwise  and  depress  the  valve  core  to
release the nitrogen .
4.  Connect  a  vacuum  pump  to  the  charge
valve to perform the vacuum pumping.
5. Start vacuum pumping and monitor this
process until all gas is pumped out. When the
color  of  oil  in  the  suspension  cylinder  is
darkened homogeneity, it indicates that it is
pumped out.
Note: It is not allowed to pump the oil from the
suspension cylinder.
6. Stop vacuum pumping.
7. Slowly lower down the frame to make the
dimension “A”(the distance between the center
of pin and end cap of guide sleeve ,See Fig.8)
equal to 205mm.
8. Release all residual gas pressure in the
suspension cylinder as step 3.
9. With cylinder rod in its right position (“A”
= 205mm), open plugand pay attention to oil

flows or not. If no oil flows, fill oil according to

the following requirements when oil level is
lower.
10.  Remove  the  plug  and  charge  valve
from  the  piston  rod. Attach  hose  from  a
pressure  pump  filled  with  hydraulic  oil
specified  in  chapter36.1“LUBRICATION
AND  MAINTENANCE”  to  oil  fill  port.The
approximate  volume  required  for  initial  oil
charging of each front suspension cylinder is
about 23L.
Note: In a cold region, a synthetic hydraulic

fluid(Conoco/Philips synthetic R&O or similar

products) is recommended as a substitute

product. This fluid should have the following

characteristic:

Front Axle Assembly

ISO viscosity grade: 46; solidification
temperature: -70°C (-55°C); PAO synthetic
agent, allowing to use normal insulation
device.
11. Fill the cylinder until oil flows free of air
bubbles from charging valve port. It may be
necessary to wait 30 or more minutes after
nitrogen pressure has been released to clear
the foam which has formed inside the cylinder.

12.Remove oil fill equipment, reinstall plug and

nitrogen charging valve in the ports .

Note:

If vacuum pumping have not be done

before oil filling, oil fill should accord to the
following procedure in order to exhaust the air
of cylinder:
a.  Remove the plug  in piston rod and plug in
the cylinder tube assy. meanwhile the charge
valve should not be removed.
b.  Attach oil fill equipment to the plug port
and fill the cylinder until oil flows free of air
bubbles from plug port. Reinstall plug  in the
port of cylinder tube assy. and remove nitrogen
charging valve in the ports .

c. Go on filling the cylinder with the plug port.

Stop oil filling until the oil flows free of air
bubbles from charge valve port, and remove

oil fill equipment. Reinstall plug and nitrogen

charging valve in the ports .
13. Charging suspension cylinder with the
nitrogen according to the following procedure.

Charging nitrogen

warning

Use dry nitrogen to charge cylinder. Do not

use a gas such as oxygen which ,if used

by mistake for pressurizing, will explode

violently when coming into contact with oil

or grease, possibly causing personal injury

and property damage.

Numbers in parentheses refer to Fig.8, unless

otherwise specified.

To charge both cylinders simultaneously with
nitrogen, use the charging assembly which
including a tee

fitting

（

，

Fig.7

）

, line (8

，

Fig.7

）

, Cut-off valve (5, Fig.7) and Nitrogen

charging joint (9, Fig.7) . Refer to Fig.7
'nitrogen charging tool.

Front Axle Assembly

The user provides the nitrogen cylinder and pressure regulator

Fig.7 Nitrogen charging assembly

1. Elbow

5. Cut-off valve

9. Nitrogen charging joint

2. Bleeder valve

6. Pipe joint

10. Pipe joint

3. Pressure gauge

7. Pipe joint

4. Tee piece

8. Line

Cut-off valve

When a single suspension cylinder is inflated,

only one side may be controlled.

The user provides the nitrogen cylinder,

pressure regulator and instruments.

Fig.8 Charge of Front Suspension Cylinder

A: The distance between center of pin and end cap of guide sleeve

Position for oil filling: A=205mm Empty : A=410mm Loaded: A=320mm

1. Charge valve

3. Cut-off valve

5. Pressure regulator

charge

joint

4. Nitrogen cylinder

6. Pressure gauge

Front Axle Assembly

warning

Use dry nitrogen to charge cylinder. Do not

use a gas such as oxygen which ,if used

by mistake for pressurizing, will explode

violently when coming into contact with oil

or grease, possibly causing personal injury

and property damage.

Note

: Use the gas pressure regulator installed

on the nitrogen cylinder to protect the
pressure gauge (The nitrogen cylinder is not
supplied with the nitrogen charging assembly).
An accurate and reliable pressure gauge
is very critical to the correct adjustment of
suspension.

Note

: When the charge valve protecting

cover is removed, no residual gas pressure
is allowed. If any, the protecting cover can
be removed after the pressure is completely
discharged.
1. Position the truck at a safe and flat road
surface. The  truck  must  be  parked  stably
without  applying  friction  brake  system  of
mining truck.
2. Remove cover of the charge valve carefully
because residual gas pressure may exist.
3. Connect the charge component (closing
the cut-off valve) to charge valve(1,Fig.8) on
suspension  cylinder  and  the  gas  pressure
regulator on the nitrogen cylinder.
1) Connect the hoses of two ends installed
with the Nitrogen charging joint(2,Fig.8) to
the charge valves(1,Fig.1)of front suspension
cylinder respectively.
2)  Connect  the  other  end  to  the  nitrogen
cylinder.
4. Adjust the gas pressure regulator to about
2000kpa.
Note: Protect the pressure gauge carefully
to avoid excessive pressure. The pressure is
easy to exceed 7000kpa.

Front Axle Assembly

5. Charge the suspension cylinders according
to the following steps:
a. Rotate the small hex nut on the charge
valve (1, Fig.8) of suspension cylinder
counterclockwise for two or three turns to
make the internal valve move away from the
seat.
b. Rotate the “T” handle of nitrogen charge
joint (2, Fig.7) clockwise until it cannot be
turned any more. Open the check valve of

inflation joint.
c. Open the cut-off valve (3, Fig.8), and inflate

the suspension cylinders at both sides with

the same pressure. During the inflation, open

slowing and intermittently close the cut-off
valve (3, Fig.8) until the distance A between
the center of pin and end cap of guide sleeve
is equal to 395mm (the allowable range of
error is 10mm).
d. When the height ‘A’ is reached (Fig.8), turn
off the pressure regulator (5, Fig.8) on the
nitrogen cylinder, close the cut-off valve(3,
Fig.8), rotate the hex nut on the charge valve
(1, Fig.8) of suspension cylinder clockwise and
close the internal valve. Rotate the T-shape
handle of nitrogen charge joint (2, fig.8)
counterclockwise until it cannot be turned any
more.
Note 1: In the charging process, the gas
should be slowly added and the flow of gas
should be periodically stopped to allow the
suspension cylinders in the left and right sides
to reach balance. The correct process will vary
with the equipment, materials and operators.

No excessive inflation is allowed; otherwise, it

will lead to the excessive extension of cylinder

body and damage of fixing bolts on the piston.

Note 2: To check the pressure of nitrogen
cylinder (4, Fig.8), close the cut-off valve (3,
Fig.8), turn on the gas pressure regulator (5,
Fig.8)slowly on the gas cylinder and observe
the reading of the pressure gauge (6, Fig.8).
The pressure in the gas cylinder must be
higher than 7000kpa.

Note 3: To check the pressure in the cylinder,
turn off the gas pressure regulator on the gas
cylinder, open the cut-off valve (3, Fig.8) and
observe the reading of the pressure gauge (6,

fig.8).

Note 4: If height of unload isn’t correct, repeat
the  previous  procedure  to  add  or  reduce
charging pressure by the increment of 150kpa.
The  increment  is  a  critical  parameter  for
suspension cylinder charging to get a correct
height of no-load state.
Note 5: If the mining truck operated in the
colder  environment,  it  is  recommended  to
raise the height of unload state by 10~20mm
to compensate for the effect of temperature
reduction.
6. Close the cut-off valve and turn off the gas
pressure regulator.
7.  Remove  the  charge  device  and  check
nitrogen charge valves (1) for leakage with
soapy water.
Note: In case of any leakage in the spool of
charge valve:
1)  Check  the  torque  of  spool. The  torque

should be 0.35 - 0.45N•m.

2) If the leakage cannot be stopped, check the
spool for damage or contamination. Replace it
if necessary. All suspension cylinder pressure
should be released before the spool is
removed with oil charging assembly.
8. Install the cover of charge valve. The torque

is 4.5 - 5.5N•m.

9.  Run  the  mining  truck  about  24  hours,
perform  the  procedure  of  inspect  un-
load height again, and make adjustment if
necessary.
Note: On new or rebuilt cylinders, the seals
and wipers may grip the piston rods tighter
and  make  it  difficult  to  obtain  the  correct
height shown in Fig.8. If this happens, the
cylinders should be charged as accurately as
possible. In addition, the height of suspension
cylinder should be checked again according
to the following table after the truck runs for

Front Axle Assembly

several days. The cylinder pressure shown
in table.2 is guide only. Cylinders should be
charged according to the height 'A' specified
in the Fig.8 and NOT solely on the basis of
monitoring cylinder pressure.

Tab.2 Front Cylinder charging height and pressure

Cylinder height 'A'

Cylinder pressure

Truck at Empty

A=410mm

3.8MPa

Loaded

A=320mm

7MPa

Maintenance

Visually check suspension cylinder heights
daily

（

Fig8&Tab.2

）

. Lubricate the suspension

cylinders at service intervals and with lubricant

specified in Chapter 36.1 “LUBRICATION AND

MAINTENANCE”.

Tab.3 Special torque specifications

Fig. No.

Item No.

Name

Torque (N•m)

1&5

Bolt

136

1&5

Bolt

136

1&6

Plug

1&6

Plug

1&6

Charge valve

Front Axle Assembly

2.2 Steering Mechanism

Fig.1 Steering mechanism

1. Tie rod assembly

6. Washer

11. Washer

2. Pin spacer

7. Bolt

12. Crank pin assembly

3. Dust cover

8. Steering cylinder

13. Crank assembly

4. Dust cover

9. Cylinder pin assembly

5. Tie rod pin assembly

10. Bolt

Front Axle Assembly

Description

Layout of steering mechanism refer to Fig.1.
There  are  two  single  stage,  double  acting
steering cylinders (8) installed on the truck.
These exert the necessary hydraulic force
on the steering arm assemblies (A) to pivot
the front wheels. Single stage, double acting
means that the piston rod can have oil applied
to  either  side,  extending  or  retracting  the
piston rod.
Steering  cylinder  (8)  piston  rod  end  is
connected  to  steering  arm  assembly  (A),

positioned by pin spacer (2) , fixed to steering

arm assembly by tie rod pin assembly (5), bolt
(7) and washer (6).
Steering cylinder (8) base end is connected
to frame, positioned by pin spacer (2), fixed
to frame by cylinder pin assembly (9), bolt (7)
and washer (6).
Steering tie rod assembly (1) is positioned
by pin spacer (2), connected to steering arm
assembly (A) and crank pin assembly (13)
respectively through tie rod pin assembly (5),
bolt (7) and washer (6).

Removal

Numbers in parentheses refer to Fig.1.
1. Position the truck in a level work area, be
sure the body is completely lowered, apply the
parking brake and switch off the engine.
2. Turn steering wheel in both directions
s e v e r a l t i m e s t o r e l i e v e p r e s s u r e i n
accumulator and steering system.
3. Block all wheels properly.
4. Switch the battery to the 'OFF' position.

Steering tie rod assembly

1. Support tie rod assembly (1) with suitable
lifting device.
2. Remove bolt(7) and washer (6). Remove tie
rod pin assembly (5) at one end of tie rod (1)
from left side steering arm assembly (A). At

Front Axle Assembly

Fig.2 Crank assembly

the same time, remove pin spacer (2) and dust
cover(3).
3. Remove bolt(7) and washer (6). Remove
tie rod pin assembly (5) at another end of tie
rod (1) from crank assembly (13). At the same
time, remove pin spacer (2) and dust cover(3).
Complete the disassembly of left side steering
tie rod assembly (1).
4.  Repeat  Steps  1~3  to  remove  right  side
steering  tie  rod  assembly  (1).  Place  the
disassembled  parts  in  a  clean  work  for
assembly.

Steering cylinder

5. Support steering cylinder (8) with suitable
lifting device.
6. Remove bolt(7) and washer (6). Remove tie
rod pin assembly (5) at the piston rod end of
steering cylinder (8) from left side steering arm
assembly (A). At the same time, remove pin
spacer (2) and dust cover(4).
7. Remove bolt(7) and washer (6). Remove
cylinder pin assembly (9) at the base end of
steering cylinder (8) from frame. At the same
time, remove pin spacer (2) and dust cover(4).
Remove left side steering cylinder (8).
8. Repeat Steps 5~7 to remove the right side
steering cylinder (8). Place the disassembled
parts in a clean work for assembly.

Steering crank assembly

9. Support crank assembly (13) with suitable
lifting device.
10. Remove bolt (10) and washer (11),using a
mild steel drift ,drive crank pin assembly(12)
out from crank housing of frame.
11. Remove crank assembly (13), Place
the disassembled parts in a clean work for
assembly.

Disassembly

Crank assembly

Disassembly of crank assembly refer to Fig.2

Front Axle Assembly

1.Crank welding body
2.Crank inner spacer

Crank assembly comprises of crank welding
body(1)  and  crank  inner  spacer  (2),  crank
assembly swing around crank pin assembly
after  assembled.  Check  wear  condition  of
crank  inner  spacer  (2),  if  bad  condition,
change is needed.
1. Heating crank assembly partly.
2. Drive crank inner spacer (2) out from inner
bore of crank assembly, using tools such as
brass rod.

Steering tie rod assembly

Disassembly of tie rod assembly refer to Fig.3
Tie rod assembly comprises of tie rod (2), left
rod end bearing (1), right rod end bearing (5),
tie rod clips(3) and fasteners, which can keep
alignment of front wheels with this adjustable

Front Axle Assembly

1. Rod end bearing(Left-hand)

4. Bolt

7. Nut

2. Tie rod

5. Rod end bearing(Right-hand)

3. Tie rod clip

6. Washer

Fig.3 Tie rod assembly

structure. With rod end bearing (1and 5)
screwed in, tie rod (2) is clamped by up and

down tie rod clips (3) and fixed by bolt (4), nut

(7), and washer (6).
1. Record the assembling length before
disassembly.
2. Remove tie rd clips (3) ,bolt (4), nut (7)and
washer (6) , take down rod end bearing (1and
5).
3. Place disassembled parts in a clean work
for assembly.

Assembly

Crank assembly

Disassembly of crank assembly refer to Fig.2
1. Heating crank assembly (1) partly.
2. Drive crank inner spacer (2) into inner bore
of crank assembly, using tools such as brass
rod.

Steering tie rod assembly

Numbers in parentheses refer to Fig.3.
1. Place tie rod (2) in a vice. Screw rod
end bearings (1 and 5) into tie rod (2) until
assembled length recorded is obtained.
2. After installation is completed, and front end
alignment is checked and corrected, assembly
up and down tie rod clips (3) and tighten nut (7)
, bolt(4) and washers (6).

Installation

Caution

: Tighten all fasteners without special

torques specified to standard torques listed
in Section 36.2 ‘Technical Conditions for
Tightening Torque of Standard Bolts and Nuts'.

Crank assembly

Numbers in parentheses refer to Fig.1.
1. Supported with suitable lifting device,
assembly crank assembly (13) into crank
housing of frame.
2. Drive crank pin assembly (12) into crank
assembly (13) and crank housing of frame,

Front Axle Assembly

fixed onto frame by washer (11) and bolt(10).

Steering cylinder

3. Support steering cylinder (8) with suitable
lifting device.
4. Assembly base end of steering cylinder
(8) into frame, with pin spacer (2) and dust
cover(4) assembled ,insert cylinder pin
assembly (9),and fixed into frame by bolt(7)
and washer(6).
5. Assembly piston rod end of steering cylinder
(8) into left side steering arm (A), with pin
spacer (2), dust cover (4) assembled ,insert tie
rod pin assembly (5) ,and fixed into left side
steering arm (A) by bolt(7) and washer(6).
6. Repeat steps 3~5 to assembly right side
steering cylinder (8).

Steering tie rod assembly

7. Support tie rod assembly (1) with suitable
lifting device, assembly into space between
crank assembly (13) and left side steering arm
assembly (A), keeping mounting hole aligned.
8. Assembly pin spacer (2) and dust cover
(3),insert tie rod pin assembly (5), fixed
into crank assembly (13) and steering arm
assembly (A) with bolt (7) and washer (6).
9. Repeat steps 7~8 to assembly right side
steering tie rod assembly (1).

Alignment

Numbers in parentheses refer to Fig.3.
Correct front end alignment is dependent on
three basic fundamentals.
a. Caster-Forward and rearward tilt of the axle
assembly.
b. Camber-Outward tilt of the top of the front
wheels.
c. Toe-in - Inward turning of the front wheels.
Note: Caster and camber are built into the
truck and are not adjustable.
1. Check for toe-in only when the truck is
empty and crank is centered. Use a slide bar
attached to the wheel rim edge to make this

Fig.4 Plan View of Wheel Alignment
Wheel (toe-in) adjustment dimension:
Y=8~12mm

Front Axle Assembly

Front end of truck

X+Y

Centerline

check, required toe-in refer to Fig. 4.
2. Loosen nut (7) and bolt (4) at each end of
tie rod assembly. Turn tie rod (2) with a pipe
pliers until correct toe-in dimension obtained,
refer to Fig.4.
3. When tie rod assembly lengths have
been established, fixed rod end bearings (1
and5) into tie rod (2) with nut (7), bolt (4) and
washers(6).

Maintenance

Every 50 Hours - Lubricate pin assemblies
with grease specified in Section 36.1
‘LUBRICATION AND MAINTENANCE’.

Special tools

There are no special tools required for
procedures outlined in this section. Refer to
Section 36.3 ‘MAINTENANCE TOOLS’ for part
numbers of general servicetools required.

Front Axle Assembly

SANY SRT95C Off-Highway Truck. Service Manual - page 6