Dismantling of Screw Shafts
1) The screw shafts may only be dismantled while the processing section is hot. When sticky products are processed, operate the CTE for approx.10 min with a cleaning product before dismantling. Then stop the extruder and the auxiliaries.
2) All discharge parts must be dismantled. The area in front of the machine required for dismantling the screw shafts must be cleared. Make hoisting equipment available for dismantling and suspending the screw shafts.
3) Switch off the die head heater, and keep the heaters of other zones working.Take out the pressure and temperature sensor at the die head. Put on thick asbestos gloves and remove the die head and screen changer, and the heater if necessary. Clean the die head, screen changer and the melt remains at screw ends．
4) Remove the screw tip (left-hand thread) with the screw tip wrench, Then screw remove tool (with a screw head), screwing in the screw end. Another remove tool (with a screw channel) grooved directly set on the back the small screw on the cap screw to pull out of the barrel.
5) Loosen the threaded rings on the screw shaft couplings with a hook wrench and remove the split rings. Pull the screw shafts out of the processing section.
6) Remember the marks on the screw ends with spline couplings. While assembling the user shall fix the saews on the original marks. ie.. the two screws cannot shift the position each other. Note: spline coupling to the gearbox direction is right-hand thread, to die head direction is left-hand thread.
7) Continue to pull the screw shafts out until screw shaft project from the processing section. Lift the saew shafts up evenly.
8) If only one hoisting device is used to dismantle the screw shafts, the projecting screw shaft ends must be supported when passing over from the processing section. While partly disassembled, the screw shafts are not allowed to be suspended.
9) Level the screw shafts with the hoisting gear and pull them completely out of the processing section. Place the screw shafts on 3 wooden supports and secure them.
10) The melt remains on tHe surface of shaf-ts should be cleared away thoroughly. If the screw shaft is not in use for some time, the user shall [iang it vertically to avoid deforming.
11) In any case, local heating of the screw shafts with a flame is to be avoided since this could affect the hardened layer. At uniform heat distribution, the max. permissible surface temperature is 450℃for the screw shafts. Hard knocks and blows are to be avoided during dismantling and transportation of the screw shafts to prevent deformation.
Chinaplas 2019 in Guangzhou