Tightening Torque - Bosch PS40 Consignes De Fonctionnement/Sécurité

BM 2610958960 06-08

TIGHTENING TORQUE

The tightening torque depends on the duration
of the impacting/tightening action. The largest
tightening torque is achieved after approx. 6 to
10 Sec. impacting/tightening action.
The torque build-up depends on the
following factors:
• Hardness of the bolts/nuts.
• Type of washer (disk washer, spring washer,
seal).
• Hardness of the material to be joined.
• Lubricating effect at the surfaces of the
junction.
This leads to the following application cases:
FASTENING WITH SCREWS
This procedure shown in (Fig. 6) will enable
you to fasten materials together with your tool
without stripping, splitting or separating the
material.
First, clamp the pieces together and drill the
first hole 2/3 the diameter of the screw. If the
material is soft, drill only 2/3 the proper
length. If it is hard, drill the entire length.
Second, unclamp the pieces and drill the
second hole the same diameter as the screw
shank in the first or top piece of wood.
Third, if flat head screw is used, countersink
the hole to make the screw flush with the
surface. Then, simply apply even pressure
when driving the screw. The screw shank
clearance hole in the first piece allows the
screw head to pull the pieces tightly together.
RUNNING NUTS AND BOLTS
Variable speed control must be used with
caution for driving nuts and bolts with socket
set attachments. The technique is to start
slowly, increasing speed as the nut or bolt runs
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Hard case: The joining of metal to metal with
a disk washer. The maximum torque is
reached after a relative short impacting/
tightening action.
Medium case: The joining of metal to metal
where spring ring washer, disk spring washer,
stud bolts or bolts/nuts with conical seats are
used.
Soft case: The joining of e.g. metal to wood
or insulation material.
For middle or soft joining cases, the maximum
tightening torque is less as for hard cases.
Therefore, a longer impacting/tightening
action is necessary to arrive at the maximum
tightening torque.
down. Set the nut or bolt snugly by slowing the
tool to a stop. If this procedure is not followed,
the tool will have a tendency to torque or twist
in your hands when the nut or bolt seats.
FASTENING WITH
SCREWS
1. Drill 2/3 diameter and
2/3 of screw length for
soft materials, full
length for hard
materials.
Apply a slight
even pressure
when driving
screws.
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2. Drill same
diameter as
screw shank.
3. Countersink
same diameter
as screw head.
Screw
FIG. 6