Operation method of Extruder
Operators must be familiar with the structural characteristics of the extruder they operate,In particular, it is necessary to correctly master the structural characteristics of the screw,Control instrument characteristics for heating and cooling,mould characteristics and assembly, etc.In order to correctly grasp the extrusion process conditions,Operate the machine correctly.
1、The preparatory work before starting the machine
(1) Keep raw materials dry.Sieve the raw material to remove agglomerated aggregates and mechanical impurities
(2) Check whether the water, electricity and gas systems in the equipment are normal, to ensure that the water and gas lines are unblocked and no leakage, whether the electrical system is normal, whether the heating system, temperature control and various instruments work reliably.Monitor the low speed test of auxiliary engine and observe whether the equipment is running normally.Start the vacuum pump of the setting table and observe whether the vacuum pump works normally.Lubricate in various parts of equipment
(3) According to the product variety, size, choose the specifications of the mould.
① Connect mould with extruder
② Before connect the mould should inspect the inside of mould whether its smooth.if not need polish,then cove the silicone oil.
③ Connect every parts of mould by order. Cove silicone oil screws and flange.
④ Compress the mould with flange
⑤ Make extruder and mould flange in same level
⑥ Compress screw of flange and install heating ring
⑦ Install auxiliary engine( shaper ). Check extruder auxiliary(shaper) and haul-off in same line.
⑧ Heating(extruder, mould)temperature up to 140C.
⑨ Load material
2、 start production
(1) When temperature arrived 140 C check and compress screw again make sure no material out from the connect of mould and exturder.
(2) Start and increase speed slowly.when material come from mould need cold and through shaper then haul-off .start those devise. Attention do not stand in front of the mould its danger
(3) Through shaper When material come out from mould smoothly. Smoothly means bright surface，no scrap，no bubble.no color change，no burn .Squeeze the extrusion material by hand to a certain extent without burr, crack, there is a certain elasticity. Its good plasticizing.if not good plasticizing reduce speed，temperature until good.
(4) Make recorder
3、stop
(1) Stop load material first.keep machine running until material finished .can see screw directly. Power off stop to heating.
(2) Power off extruder stop to running
(3) open mould clean.
(4) Remove mould make extruder running again.make sure all material out off screw. stop
二、extruder care and maintenance
(1) Routine maintenance is a regular routine work that does not take up operating hours of equipment and is usually completed during start-up.The key point is to clean the machine, lubricate the moving parts, tighten the thread parts which are easy to become loose, timely check and adjust the motor, control instruments, working parts and pipes, etc
(2) Regular maintenance is usually carried out after the extruder runs continuously for 2500-5000h.The machine needs to be broken up to inspect, measure and appraise the wear condition of the main parts, replace the parts that have reached the specified wear limit, and repair the damaged parts
(3) Do not allow empty operation, in order to avoid screw and machine strip rolling.
(4) If there is any abnormal noise during the operation of the extruder, stop it immediately for inspection or repair
(5) Strictly prevent metal or other sundries from falling into the hopper, so as not to damage the screw and barrel.In order to prevent iron debris from entering the barrel, magnetic absorbing parts or magnetic racks can be installed at the feeding mouth of the barrel to prevent debris from falling into the barrel. The materials must be screened in advance
(6) Pay attention to the clean production environment, do not let garbage impurities mixed with the material to block the filter plate, affect the product output, quality and increase the resistance of the head
(7) When the extruder needs to be stopped for a long time, anti-rust grease should be applied on the working surface such as screw, machine brief and machine head.The small screw should be hung in the air or placed in a special wooden box, with wooden block pad flat, so as to avoid screw deformation or damage.
(8) Calibrate the temperature control instrument regularly to check its adjustment accuracy and control sensitivity
(9) The reducer casing maintenance of the extruder is the same as that of the general standard reducer.It is mainly to check the wear and failure of gears and bearings.The reducer casing shall use the lubricating oil specified in the machine manual, and add oil according to the specified oil level height, the oil is too little, the lubrication is correct, reducing the service life of the parts;Too much oil, high heat, energy consumption, oil easy to deteriorate, the same lubrication failure, resulting in damage parts
(10) The cooling water pipe attached to the extruder is easy to form scale on the inside and corrode and rust on the outside.Careful inspection should be made when raising, too much scale will block the pipeline, can not reach the cooling effect, serious corrosion will leak, so the maintenance must be taken descaling and anti-corrosion cooling measures.
(11) To drive the direct current motor screw rotation should focus on checking brush wear and contact, the insulation resistance value of the motor whether above the rated value should also be often measured.In addition to check whether the wire and other components rust, and use protective measures.
(12) Assign special personnel to take charge of equipment maintenanc And put the detailed record of each maintenance and repair into the factory equipment management file
