Sterlco BP 1000 Series Beside the Press Granulators - Manual (Page 25)

1000 Series Granulators Chapter 5: Maintenance 25 of 45
5-3 Replacing and Adjusting the Knives
During use, the clearance between the rotor knives and the bed knives will increase due to
wear. This is a normal condition that requires re-setting this clearance once or twice before it
is necessary to remove the knives for regrinding. Check the knives weekly for wear,
clearance, exposure, and screw tightness.
When new knives are fitted to the machine, adjustment after eight hours of running time may
be required.
Before assembling a new or reground set of knives, make sure the knife seats and mounting
holes are clean. Do not use grease or oil on screws or tapped holes when assembling the
knives.
Knives must be replaced in complete sets; otherwise it will not be possible to obtain even
clearance between the rotor knives and bed knives.
Before applying a wrench to any knife bolt, be certain that the rotor is blocked to prevent
rotation. One such method is to use a block of wood at least 1 1/2” thick between a knife
and a fixed portion of the frame.
Rotor Knives
We recommend that the rotor knife screws be replaced with new screws every sixth knife
change to reduce the risk of screw failure due to overstretching. Screws must be replaced
with the type specified in the spare parts list. Use the following procedure to replace or adjust
the rotor knives:
Rotor knives should be changed one seat at a time to prevent rotor from
being rotated in an out-of-balance condition.
1. Access the cutting chamber as directed in Section 3-4 on page 20.
2. Remove or set back the bed knives to clear the rotor knives so that the rotor can
revolve freely.
3. Remove rotor knife bolts and knives on each seat.
4. Thoroughly clean knife seats.
5. Install new or sharpened knives on each knife seat, making sure that the rotor is still
blocked to prevent it from rotating while installing each knife.
6. Lightly tighten the screws and check that a 0.04 mm (0.0015”) feeler gauge will not
pass between the back of the knife and the knife seat. Tap the knife gently with a
rawhide hammer if necessary to close the gap.
7. Tighten the rotor knife screws evenly and torque them to 100 ft. lb. (135 Nm)
Bolt threads should not be oiled. Wipe thread with an oil-dampened
cloth.
8. Re-check the gap between the back of the knife and the knife seat. If necessary,
readjust the knife.
9. Adjust the clearance between the bed knives and rotor knives. (See “Bed Knives” on
page 26.)