Wipe the device with a clean cloth or blow it out with compressed air at low pressure.
Excessive accumulation of metal dust can cause electricity to be conducted from the
internal parts to exposed metal parts!
If the power tool's power cord is damaged, it must be replaced with a specially
prepared power cord that is available from the customer service organization.
Only put the power tool on the nut / screw when it is switched off, otherwise the
rotating tool bits may slip off.
The torque depends on the duration of the impact. The maximum torque achieved
results from the sum of all individual torques achieved through impacts. The maximum
torque is reached after a stroke duration of 3-5 seconds. After this time, the tightening
torque only increases slightly. On the other hand, the gear housing may heat up
heavily.
Note: The consequences of excessive heating may cause high wear and tear on all
hammer mechanism parts and require high lubricant.
Screw connections with a hard, springy or soft seat
With a springy or soft seat, the maximum tightening torque is lower than with a hard
seat. A significantly longer impact time is also required.
Renewal of accessories
Worn or damaged accessories must be replaced immediately.
The following use cases result accordingly:
- A hard seat is provided for screw connections from metal to metal when using
washers. The maximum torque is reached after a relatively short impact time
(steep characteristic curve). Unnecessarily long striking times only damage the
machine.
- A Resilient fit is given for screw connections from metal to metal, but when using
spring washers, disc springs, studs or screws / nuts with a conical seat and when
using extensions.
- A soft fit is given for screwing of metal on wood, or use of lead or fiber washers
as a base.
If the torques achieved in a sequence of impacts are measured in the experiment and
transferred to a diagram, the curve of a torque curve is obtained. The height of the
curve corresponds to the maximum achievable torque, the steepness shows the time
in which this is achieved.
A torque curve depends on the following factors:
- Strength of the screws / nuts
- Type of base (washer, disc spring, seal)
- Strength of the material to be screwed
- Lubrication conditions on the screw connection
The impact duration must be determined for each required tightening torque. The
tightening torque actually achieved must always be checked with a torque wrench.
7
Work instructions
Summary of Contents for MMT A170 703
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