Maintenance And Inspection; Important - Hitachi WR 8DH Mode D'emploi

English
(3) Diameter of bolt
The tightening torque differs with the diameter of
the bolt as shown in Fig. 12, 13 and 14. Generally
a larger diameter bolt requires larger tightening
torque.
(4) Tightening conditions
The tightening torque differs according to the torque
ratio; class, and length of bolts even when bolts
with the same size threads are used. The tightening
torque also differs according to the condition of the
surface of workpiece through which the bolts are
to be tightened. When the bolt and nut turn together,
torque is greatly reduced.
(5) Using optional parts
The tightening torque is reduced a little when an
extension bar, universal joint or a long socketis
used.
(6) Clearance of the socket
A worn or deformed hex or a square-holed socket
will not give an adequate tightness to the fitting
between the nut or anvil, consequently resulting in
loss of tightening torque.
Using an improper socket which does not match
to the bolt will result in an insufficient tightening
torque. Matching socket and bolt sizes are shown
in Table 1 and 2.

MAINTENANCE AND INSPECTION

1. Inspecting the socket
A worn or deformed hex or a square-holed socket
will not give an adequate tightness to the fitting
between the nut or anvil, consequently resulting in
loss of tightening torque. Pay attention to wear of
a socket holes periodically, and replace with a new
one if needed.
2. Inspecting the mounting screws
Regularly inspect all mounting screws and ensure
that they are properly tightened. Should any of the
screws be loose, retighten them immediately. Failure
to do so may result in serious hazard.
3. Maintenance of the motor
The motor unit winding is the very "heart" of the
power tool.
Exercise due care to ensure the winding does not
become damaged and/or wet with oil or water.
4. Inspecting the carbon brushes (Fig. 8)
The motor employs carbon brushes which are
consumable parts. Since and excessively worn
carbon brush can result in motor trouble, replace
the carbon brush with new ones when it becomes
worn to or near the "wear limit". In addition, always
keep carbon brushes clean and ensure that they
slide freely whthin the brush holders
NOTE:
When replacing the carbon brush with a new one,
be sure to use the Hitachi Carbon Brush Code No.
999054.
5. Replacing carbon brushes
Take out the carbon brush by first removing the
brush cap and then hooking the protrusion of the
carbon brush with a flat head screw driver, etc., as
shown in Fig. 10.
When installing the carbon brush, choose the
direction so that the nail of the carbon brush agrees
11
with the contact portion outside the brush tube.
Then push it in with a finger as illustrated in
Fig. 11. Lastly, install the brush cap.
CAUTION:
Be absolutely sure to insert the nail of the carbon
brush into the contact portion outside the brush
tube. (You can insert whichever one of the two
nails provided.)
Caution must be exercised since any error in this
operation can result in the deformed nail of the
carbon brush and may cause motor trouble at an
early stage.
6. Cleaning of the outside
When the impact wrench is stained, wipe with a
soft dry cloth or a cloth moistened with soapy
water. Do not use chloric solvents, gasoline or paint
thinner, as they melt plastics.
7. Storage
Store the impact wrench in a place in which the
temperature is less than 40°C, and out of reach of
children.
NOTE
Due to HITACHI's continuing program of reserch and
development, the specifications herein are subject to
change without prior notice.

IMPORTANT

Correct connection of the plug
The wires of the mains lead are coloured in accordance
with the following code:
Blue: –Neutral
Brown: –Live
As the colours of the wires in the mains lead of this
tool may not correspond with the coloured markings
identifying the terminals in your plug proceed as follows:
The wire coloured blue must be connected to the
terminal marked with the letter N or coloured black.
The wire coloured brown must be connected to the
terminal marked with the letter L or coloured red.
Neither core must be connected to the earth terminal.
NOTE
This requirement is provided according to BRITISH
STANDARD 2769: 1984.
Therefore, the letter code and colour code may not be
applicable to other markets except United Kingdom.
Information concerning airborne noise and vibration
The measured values were determined according to
EN50144.
The typical A-weighted sound pressure level: 94 dB (A)
The typical A-weighted sound power level: 107 dB (A)
Wear ear protection.
The typical weighted root mean square acceleration
value: 7.0 m/s 2