Komatsu BR380JG-1E0, Shop Manual, Page: 19 / 841

00 Index and foreword SEN01344-00
BR380JG-1E0
5
q
If the load is unstable or the wire rope
or chains are twisted, lower the load
and lift it up again.
q
Do not lift up the load slantingly.
13) When lifting down a load, observe the fol-
lowing.
q
When lifting down a load, stop it tem-
porarily at 30 cm above the floor, and
then lower it slowly.
q
Check that the load is stable, and
then remove the sling.
q
Remove kinks and dirt from the wire
ropes and chains used for the sling
work, and put them in the specified
place.
5. Precautions for using mobile crane
a
Read the Operation and Maintenance
Manual of the crane carefully in advance
and operate the crane safely.
6. Precautions for using overhead hoist crane
k
When raising a heavy part (heavier
than 25 kg), use a hoist, etc. In Disas-
sembly and assembly, the weight of a
part heavier than 25 kg is indicated
after the mark of
4
.
1) Before starting work, inspect the wire
ropes, brake, clutch, controller, rails, over
wind stop device, electric shock preven-
tion earth leakage breaker, crane collision
prevention device, and power application
warning lamp, and check safety.
2) Observe the signs for sling work.
3) Operate the hoist at a safe place.
4) Check the direction indicator plates (east,
west, south, and north) and the directions
of the control buttons without fail.
5) Do not sling a load slantingly. Do not move
the crane while the slung load is swinging.
6) Do not raise or lower a load while the
crane is moving longitudinally or laterally.
7) Do not drag a sling.
8) When lifting up a load, stop it just after it
leaves the ground and check safety, and
then lift it up.
9) Consider the travel route in advance and
lift up a load to a safe height.
10) Place the control switch on a position
where it will not be an obstacle to work
and passage.
11) After operating the hoist, do not swing the
control switch.
12) Remember the position of the main switch
so that you can turn off the power immedi-
ately in an emergency.
13) If the hoist stops because of a power fail-
ure, turn the power switch OFF. When
turning on a switch which was turned OFF
by the electric shock prevention earth
leakage breaker, check that the devices
related to that switch are not in operation
state.
14) If you find an obstacle around the hoist,
stop the operation.
15) After finishing the work, stop the hoist at
the specified position and raise the hook
to at least 2 m above the floor. Do not
leave the sling installed to the hook.
7. Selecting wire ropes
1) Select adequate ropes depending on the
weight of parts to be hoisted, referring to
the table below.
a
The allowable load is one-sixth of the
breaking strength of the rope used
(Safety coefficient: 6).
Wire ropes
(Standard “Z” twist ropes without galvanizing)
(JIS G3525, No. 6, Type 6X37-A)
Nominal
diameter of rope
Allowable load
mm kN ton
10 8.8 0.9
12 12.7 1.3
14 17.3 1.7
16 22.6 2.3
18 28.6 2.9
20 35.3 3.6
25 55.3 5.6
30 79.6 8.1
40 141.6 14.4
50 221.6 22.6
60 318.3 32.4