Sterlco SLS Series Light Duty Shredder - Manual (Page 31)

GRN4-600 Chapter 5: Maintenance 31 of 50
Working on the Cutters
The correct grinding properties, the correct setting, and the correct mounting of the
cutters are all-important factures to ensure proper function and economic operation of the
shredder.
Replacing and checking the cutter mountings
• Certain machine parts are subject to stress while operating due to vibrations,
which can lead to the loosening of screw connections. It is very important to
check the cutter mounting screws according to the intervals in the maintenance
plan.
• Tighten the mounting screws on the cutters using a torque wrench set to the
required torque for the screw size. The required torque for the cutter mounting
bolts is 120 Nm.
• Use the table below to determine torque values. The tightening capacity
decreases on screws that have been loosened and tightened several times. New
screws of the same material must replace the cutter mounting screws after they
have been loosened and tightened several times.
Torque Value Table
Bolt Type
Grade 8.8 Grade 10.9 Grade 12.9
Nm lbf ft Nm lbf ft Nm lbf ft
M8 25 18.4 35 25.8 41 30.2
M10 49 36 69 60 83 61.2
M12 86 63.4 120 88.5 145 106
M16 210 154 295 271 355 261
M20 410 302 580 428 690 508
M24 710 523 1000 737 1200 885
Checking the condition of the cutters
The cutters become blunt after a certain number of operation hours. They need to be
checked regularly. Using blunt knives has several consequences including decreased
grinding capacity, increased current consumption of the drive motor, inexact cuts, and
overheating of the material.
Sharp knives are dangerous when while the rotor is at standstill.
Serious injury can result—especially to the hands and fingers—wear
protective gloves!