Some common failures that may occur in a large blow molding machine
(1) Sundries stuck in the extruder
In the process of hollow blow molding, it is often caused by unreasonable manipulation by some operators or accidental damage to the feeding and return crushing system equipment. The metal objects fall from the feed inlet. Screws or nuts. This kind of metal objects are pushed forward along with the plastic and get stuck in the place where the gap between the screw and the barrel is small. Under such conditions, abnormal equipment friction sounds are often heard. However, in view of the relatively loud noise of equipment operation in the production workshop Generally, it is difficult for the operator to detect such abnormal sounds early, causing the screw to continue to operate until the extruder equipment is completely jammed. In severe cases, abnormal damage to the equipment of the extruder transmission system may occur.
Although the manufacturer of the hollow molding machine assembled the magnetic frame in the feed hopper of the Blow molding machine, the stainless steel diamond block still enters the screw and barrel of the extruder because the stainless steel material will not be affected by the magnetic force. The screw and barrel were damaged.
Therefore, in the feeding hopper of the extruder or other suitable parts, add more strong magnetic iron absorption equipment, and use negative pressure to transport plastic materials, which can reduce at least about 80% of accidental damage. Similarly, certain effective measures must be taken to avoid contamination of the plastic trimmings and other materials cut out during the operation, and to ensure the cleanliness of the raw materials.
(2) The screw and barrel are abnormally locked. In the conventional production operation of the extruder, there may be a certain part of the screw and the barrel. The reason is usually the screw, the main component of the extruder. Or the processing and heat treatment of internal connecting sleeves and other parts did not meet the relevant technical requirements, and the thrust bearing of the gear reducer was worn and damaged (generally, if there is no hardware blockage in the equipment in conventional applications, you should first guess that it is the thrust bearing of the reducer Damage) or the design of the extruder itself still needs improvement.
In the disassembly and repair, the locked part can be heated to about 300 degrees, and some specially set tools can be used for disassembly. When disassembling, pay special attention to safe handling to avoid accidental damage due to insufficient strength of the tool. After disassembly, the damaged parts of the parts can be properly repaired and then continue to be applied. If necessary, the completely damaged parts can be replaced and the gear reduction box can be repaired.