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Tail shaft ......................................................................5
How to install the head shaft split sprockets
To install the split sprockets on the head shaft proceed as follows (Fig. 79):
IMPORTANT! Adhere to all weld specifications shown on Fig. 79. Failure to do so may result in sprocket failure and machine damage.
1. Release tension on the conveyor chain by removing shims from the conveyor chain take-up. (See Conveyor chain adjustment in this chapter).
2. Separate conveyor chain and fold back to clear drive shaft. (See
Conveyor chain replacement in this chapter).
3. Remove the two (2) sprocket guards located on the end of the feeder breaker.
4. Remove damaged sprockets and keys from head shaft. Old sprockets may require cutting to remove.
5. Thoroughly clean and degrease the drive shaft.
6. Insert key into shaft keyway.
7. Install both sprocket halves onto shaft and tack weld in place (see
Fig. 79 for location). Ensure sprocket alignment and proper spacing with conveyor chain.
8. Preheat sprocket weld joint to 600°F .
9. Weld sprocket halves together and do not exceed 800°F maximum interpass temperature. Ensure that the weld is smooth in the tooth area to prevent damage to the conveyor chanin bushings during chain operation.
10. If possible, cover sprocket with insulating blanket and allow weld to coolt to a maximum of 100°F before uncovering. If this is not possible, then post weld heat to 800°F.
11. Connect conveyor chain. (See Conveyor chain replacement in this chapter).
12. Adjust tension on the conveyor chain. (See Conveyor chain adjustment in this chapter).
Fig. 79: Head shaft sprocket removal and installation
Bearing (2) Head shaft Sprocket guard 3/8 X 45° weld chamfer
3/8 X 45° weld chamfer
Conveyor chain Sprocket (2) & key (2) Split sprocket (typical)
General notes:
1. Do not mix and match halves with other sprockets. 2. Install sprocket and keys on head shaft. 3. OK to temporarily tack weld sprocket halves to head shaft until welding is complete. 4. Blend and smooth welds to avoid chain roller damage.
Weld notes:
1. All welds chamfers are 1/2 X 45° except as noted above. 2. Preheat sprocket weld joint 600°F - 800°F. 3. Maintain preheat temperature during entire welding process. 4. Max interpass temperature not to exceed 800°F. 5. Use low hydrogen rod (E7018) or weld wire (Class E71T
Spec AWS A5.20). 6. Post weld heat sprocket joint 600°F - 800°F. 7. If possible/practical, bury sprocket in dirt or wrap with a welding blanket for a minimum of 8 hours or until sprocket temp reaches 100°F.
Taconite seal
(optional for one piece sprockets) Taconite seal
(optional for one piece sprockets)
Tailshaft
The tailshaft (Fig. 80) allows for even adjustments and friction free transition to the conveyor chain assembly. As soon as any component of the tailshaft is worn the component or complete tail shaft assembly must be replaced. Due to the high abrasion forces the tailshaft is subject to a very high level of wear.
The tailshaft assembly consists of the following main components:
■ tail haft
■ roller (2)
■ slide plate weldment
■ key (2)
■ roller set screw (2)
■ take-up bearing (2)
■ piston rod adapter (2)
Fig. 80: Tail shaft main components
Set screw (2)
Tail shaft Key (2)
Bearing (2)
Slide plate Roller (2) Piston rod adapter (2)
How to remove the tailshaft
To remove the tailshaft assembly (Fig. 81):
1. Remove the RTV silicone from five (5) bolt heads and remove the bolts from each end of the tailshaft retainers and lift out the retainers.
2. Make sure the grease take-up release valves are closed and pump up the grease cylinders until the grease shims are loose.
3. Release tension on the conveyor chain by removing the tail shaft shims. Open the valves on the grease cylinder take-up manifold located under the main valve bank. Pry the tailshaft toward the discharge end of the machine to fully collapse the grease take-up cylinders.
4. Disconnect, tag and cap the central lubrication hoses to the tail shaft.
5. Separate conveyor chain and fold back to clear tail shaft. (See
Conveyor chain replacement in this chapter).
6. It may be necessary to remove the take-up cylinders from the feeder frame and disengage the take-up pushrod from the take-up bearing.
7. Attach an appropriate lifting device to the tail shaft assembly and and slowly lift from machine.
WARNING! You could be seriously injured or even killed by falling loads. Observe the safe working load limits of lifting or blocking devices and keep a safe distance from suspended loads.
How to install the tail shaft
To install the tailshaft assembly (Fig. 81):
1. Apply a coat of grease to the bearing guide bars.
2. With an appropriate lifting device, insert tail shaft into the receiving end of the feeder breaker. Center the tail shaft in the feeder breaker frame, ensuring that the slots of the take-up bearing are aligned witht the guide bars and that the bearings are fully seated on the guide bars. It may be necessary to loosen the set screws of the bearing retainer collars and reposition the bearings so that the bearing slots are aligned with the frame guide bars. Apply Loctite 242 and torque set screws to 100 ft-lbs if loosened.
3. Install the take-up pushrod into the take-up bearing.
4. Fold the conveyor chain over tailshaft.
5. Connect conveyor chain (see Conveyor chain replacement in this chapter.
6. Connect central lubrication hoses and lubricate the tailshaft slide plate and take-up bearings with Spec. 100-3 grease until grease is seen coming out of the bearings and from the tailshaft slide plate tube.
7. Adjust tension on the conveyor chain (see Conveyor chain adjustment in this chapter).
8. Install the tailshaft retainers with the five (5) bolts in each side and fill the bolt heads with RTV silicone.
9. With machine running, visually inspect tailshaft to ensure that the chain is smoothly engaging the rollers.
