Precautions for shutdown of PE blown film machine

1、 Preparation before shutdown

Production plan coordination

Before deciding to shut down, it is necessary to communicate fully with the production planning department to ensure that the shutdown will not affect the delivery of subsequent orders. Notify relevant teams and maintenance personnel 24 hours in advance to prepare for shutdown.

Raw material processing

Stop adding new raw materials 2 hours in advance, so that the raw materials in the hopper are basically exhausted

Record the batch number and quantity of remaining raw materials, label and seal them properly

Clean the hopper and feeding system to prevent residual raw materials from absorbing moisture or contaminating

Product Quality Assurance

Products produced one hour before shutdown should be separately labeled and treated as transitional products. If necessary, they can be downgraded or recycled.

2、 Shutdown operation process

temperature control

Gradually reduce the heating temperature of each section by 5-10 ℃ each time, with an interval of 10 minutes

The temperature of the mold head decreases and is kept at the lower limit of the process temperature for about 30 minutes before closing

Record the temperature change curves of each section as a reference for the next startup

Screw speed adjustment

Reduce the speed to 50% of normal production and run for 10 minutes

Reduce to 30% again and run for 5 minutes

Run at a lower speed for 2-3 minutes and then completely stop

Traction and winding system

Synchronize to reduce traction speed and maintain foam stability

Stop pulling immediately when the membrane bubble becomes unstable

Stop the automatic roll replacement function after the current roll is completed during the roll up process

cooling system

The fan should continue to run for 15-20 minutes after the main engine stops

The water cooling system can only be turned off when the temperature of each section drops below 80 ℃

Check and drain the cooling water pipeline to prevent freezing and cracking in winter

3、 Equipment cleaning and maintenance

Screw and barrel cleaning

Thoroughly clean with specialized cleaning agents

After producing special colors or materials, they need to be cleaned multiple times until the discharge is colorless

After cleaning, manually rotate the screw several times to prevent it from getting stuck after cooling

Mold cleaning

Open the mold head when the temperature drops to around 150 ℃

Use copper tools to clean the lip material of the mold

Check if the mold mouth is damaged or corroded, and record the wear condition

Filter replacement

Shutdown is a better time to replace the filter screen

Record the blockage and damage location of the old filter screen

Pay attention to the direction and sealing when installing a new filter screen

Lubrication system inspection

Check the oil level and quality of each lubrication point

Add lubricating grease to key parts such as gearbox and bearings

Replace the lubricating oil that has reached the end of its service life

4、 Electrical System Management

Power off sequence

First, turn off the power to each heating zone

Turn off the main motor power again

Turn off the main power switch

The emergency stop button should be kept in the release position

Control system maintenance

Backup current production process parameters

Record alarm history and maintenance information

Dust removal treatment of control cabinet

Sensor inspection

Check the accuracy of temperature and pressure sensors

Clean detection devices such as photoelectric eyes and thickness gauges

Calibrate necessary measuring instruments

5、 Safety precautions

Warning for high temperature components

Set up warning signs for "high temperature danger"

Protective barriers should be set up in the mold area

Confirm that the temperature of each part must drop below 60 ℃ before contact can be made

energy isolation

Relieve pressure on the hydraulic system

Compressed air system emptying

Hang the "No Operation" sign

scene cleanup

Remove raw materials and waste film around the equipment

Return the tools to their original position and ensure smooth passage

Clean up oil stains in a timely manner to prevent slipping

6、 Special treatment for long-term shutdown

rust prevention treatment

Apply anti rust oil to exposed metal parts

Place desiccant inside the mold cavity

Regularly manually rotate the screw to prevent adhesion

regular maintenance

Start the auxiliary system and run it for 30 minutes every week

Monthly inspection of electrical system insulation performance

Regularly lubricate the transmission components

environmental control

Keep the workshop dry and ventilated

Covering equipment to prevent dust

Control the ambient temperature between 5-35 ℃

7、 Record and handover

Shutdown report

Detailed record of downtime reasons and time

Equipment Status Assessment Report

Next startup suggestion

shift handover record

List of Unfinished Items

Pay special attention to the issue

Consumption of spare parts

Maintain file updates

This maintenance content archive

Accumulated running time statistics

Next maintenance plan formulation

Standardized shutdown operation of PE blown film machine can not only extend the service life of the equipment, but also ensure smooth start-up and stable product quality next time. Every shutdown should be seen as a good opportunity for equipment maintenance, and through systematic management, production efficiency and economic benefits can be significantly improved. Operators should strictly follow the regulations, and management personnel should strengthen supervision and work together to do a good job in equipment management.