Komatsu PC200-8M0, Shop Manual, Page: 20 / 1254

SEN06112-00
00-200
4
PC200, 200LC, 220, 220LC-8M0
200 Foreword and general information
Foreword, safety and general information
Precautions for slinging work and making sig-
nals
q
Only one appointed worker must make signals
and co-worker must communicate with each
other frequently. The appointed signaler must
make specified signals clearly at the place
where the signaler is well seen from the opera-
tor's seat and where the signaler can
see the working condition easily. The signaler
must always stand in front of the load and
guide the operator safely.
1.
Do not stand under the load.
2. Do not step on the load.
q
Check the slings before starting sling work.
q
Keep putting on the gloves during sling work.
(Put on the leather gloves, if available.)
q
Measure the weight of the load by the eye and
check its center of gravity.
q
Use the proper sling according to the weight of
the load and method of slinging. If too thick
wire ropes are used to sling a light load, the
load may slip and fall.
q
Do not sling a load with one wire rope only. If
do so, the load may rotate or the sling gets
loose and the sling may slip off. Install two or
more wire ropes symmetrically.
k Slinging with one rope may cause turning
of the load during hoisting, untwisting of
the rope, or slipping of the rope from its
original slinging position on the load,
which can result in a dangerous accident.
q
Hanging angle must be 60 degrees or smaller
as a rule.
q
When hanging a heavy load (25kg or heavier),
the hanging angle of the rope must be nar-
rower than that of the hook.
a
When slinging a load with two ropes or
more, the larger the hanging angle is, the
larger the tension of each rope. The figure
bellow shows the variation of allowable
load in kN {kg} when hoisting is made with
two ropes, each of which is allowed to
sling up to 9.8 kN {1000kg} a load verti-
cally, at various hanging angles. When the
two ropes sling a load vertically, up to19.6
kN {2000 kg} of total weight can be sus-
pended. This weight is reduced to 9.8 kN
{1000 kg} when the two ropes make a
hanging angle of 120 degrees. If the two
ropes sling a 19.6 kN {2000 kg} load at a
hanging angle of 150 degrees, each rope
is subjected to a force as large as 39.2 kN
{4000 kg}.
q When installing wire ropes to an angular load,
apply pads to protect the wire ropes. If the
load is slippery, apply proper material to pre-
vent the wire rope from slipping.
q Use the specified eye bolts and fix wire ropes,
chains, etc. to them with shackles, etc.
q Apply wire ropes to the middle portion of the
hook.
a
Slinging near the tip of the hook may
cause the rope to slip off the hook during
hoisting. The hook has the maximum
strength at the middle part.
q Do not use twisted or kinked wire ropes.
q When slinging up a load, observe the follow-
ing.
1.
Wind up the rope slowly until the wire rope
tensions. When putting your hands on the
wire ropes, do not grasp them but press
them down from above. If you grasp them,
your fingers may be caught.
2. After the wire ropes are stretched, stop
the crane and check the condition of the
slung load, wire ropes, and pads.
3. If the load is unstable or the wire rope or
chains are twisted, lower the load and lift it
up again.
4. Do not lift up the load at an angle.
q When lowering a load, pay attention to the fol-
lowing.