Cause analysis and prevention of screw breakage in injection moulding machine
Screw fracture temperature is also related, but very few, almost all of the screw itself material toughness poor, or use a long time, renovation screw!
Raw materials, such as raw materials to add a GF "glass fiber" that raw material is the most cost screw and machine platform! This raw material fluidity is poor, the request shoots fast! Master is not good, light rocket head, and reverse ring rupture, heavy broken screw for many knots! Screw fracture can be prevented, in the use of raw materials to add GF, if the shutdown more than 3 minutes, the boot summary cleaning material pipe, the best use of pp sticky, cleaning screw, to prevent the decomposition of raw material package screw and rocket head.
When cleaning, the speed is reduced, so that the raw materials in the heat rotation fully melted, the cleaning screw for the needle point mold, the best way, to prevent adhesive paste in the static template, the use of hot material in the boot production!
In the work of a single full stop, do a good job, the volume of products have enough, stop immediately clean screw, so that the residual raw materials of screw out, and then use PP or cleaning screw raw materials.
Process problems, back pressure and screw fracture also have relations! Back pressure is too large, when feeding, screw after the increase in force, you can also make the screw break!
The end of the injection point can not be zero, especially with the high-speed injection machine "storage pressure gas" shooting is very easy to damage the rocket head! The residual quantity should be controlled well. Remember, the most critical, and then manually shoot out must be the guaranteed pressure time to zero, to prevent the end of the shooting glue zero!
The molding temperature should be controlled well. When the boot is on, pay attention to the loose back and then shoot out, because when there is no loose back, the rocket head has a raw material package, if the direct washing or shooting, can directly cause the rocket head, reverse the ring rupture, remember to loose back and then shoot out, so that the rocket head of raw materials and rocket separation!!
Remember that no matter what raw materials used, downtime does not produce, we must put the remaining raw materials out, for the next production ready!