Die maintenance and replacement of granulator

The granulator die is a valuable, high-precision part of the granulation line, which requires a lot of maintenance in addition to careful operation.

In order to prevent downtime caused by the failure of the die head, it must be operated correctly and protective measures must be taken to ensure that the die head is always available. Careless or mishandling during maintenance, cleaning or adjustment is a major cause of die head damage, so all personnel who come into contact with the die head must be rigorously trained. The operator must understand the function of the die head, know the effect of temperature changes, the adjustment of the die hole or the adjustment rod on the quality of the product, and also pay attention to the source of the failure. The operator must also understand the importance of maintaining good contact between the heater and the die, and be able to judge whether there is a fault on the production line, and where is the fault?

When there is pulsation in the extrusion of the single-screw granulator, the blocking block of the slot die cannot be adjusted continuously (generally, the device is not designed for this purpose). He must also be able to tell if the inlet pressure is out of range based on the measurement of the inlet pressure. Also note that the die or choke block cannot be adjusted quickly, but should be changed moderately in the adjacent area, otherwise the bolts and choke block may be damaged. (Note: Only use a scraper made of soft materials (copper, brass, soft aluminum) to remove the melt in the die to avoid scratching the wound die, and the die gap width of the die head should also be measured with soft materials such as brass gauges .even slight scratches can cause streaks on the extrudate and reduce product quality)

When the die head needs to be replaced frequently, especially in film and sheet extrusion, it is often the case that special personnel must be assigned to operate it. Some people have experience in dismantling, inspecting and installing new die heads before use. The disassembly, cleaning, repair and maintenance of the die head should be carried out at a designated place, which should be far away from the production site. Pay attention to cleaning and pad it with corrugated plates. When using it, a small crane is provided. When lifting manually, the iron chain of the pulley block is often Damage the die. To avoid this danger, consider using hemp rope, which can greatly reduce the time to change the die.

The heater inspection is also necessary, and the pre-heater should be equipped with a certain number of heating wires and control systems. Individual control of each die heater is not necessarily required at this time, but this depends on the size of the die. If the die head needs to be cleaned, the main bolts of the die head must be loosened, but do not need to be removed, the die head is still connected with the granulator, just loosen the one related to the runner.