Accurate laser alignment of your equipment can help you save both time and money. An investment in laser alignment helps since you have lower costs in terms of replacement parts as well as a decrease in down-time, lower power consumption and also less wear and tear of critical components. There is a very small tolerance between the screw and the extruder barrel and this is the reason why laser barrel alignment is one of the commonest uses of laser alignment.
When extrusion barrel alignment is carried out, the barrel is aligned relative to the output shaft of the gearbox and this increases dramatically the life as well as the output of the extrusion line over the life cycle. The criticality of proper alignment increases with the length of the extrusion screw. Therefore, a misalignment of only 0.060” on a 4” 24:1 screw will need more than 9000 lb force to be applied on the screw in order to bend it so that it conforms with the misaligned barrel. This force will mean greater wear on the screw as well as the barrel that will fail prematurely.
If the extrusion barrel alignment is not ensured the tolerance between the barrel and the screw is consequently compromised. This means that the extruder output is also reduced and the line efficiency and your profits both suffer. If laser barrel alignment is not carried out in time and misalignment is allowed to continue you may even have a screw breakage. Each time either the screw is removed or whenever the gearbox is decoupled from the extruder, laser alignment must be carried out to prevent improper alignment. The 10 hours that a complete laser alignment takes is a very small investment for your ultimate savings in cost and time. Precision Products Inc (PPI) carries out this task with a device that is capable of measuring a deviation of less than 0.001”.
For more details : http://www.ppiparts.com/laserBrochureAug2011.html
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