Packaging machinery and equipment, as the core devices of production lines in industries such as food and pharmaceuticals, their cleanliness is directly related to product safety, equipment service life, and production efficiency. Establishing a scientific cleaning and maintenance system is the key to ensuring the stable operation of production lines. This article provides enterprises with a comprehensive cleaning and maintenance operation guide from the dimensions of basic principles, material adaptation, machine-specific procedures, and process standards.
1. Basic Cleaning Principles and Classification Standards
(1) Three Core Principles
- Food Safety Priority Principle: For the cleaning of food-contact packaging machines, chemical residues and microbial contamination must be eliminated. Cleaners must be food-grade products, and residue testing must be conducted after cleaning to ensure compliance with food hygiene standards and avoid product safety risks from the source.
- Equipment Protection Principle: During the cleaning process, damage to precision components should be avoided. For example, high-pressure water flow is strictly prohibited from directly impacting electronic sensors, and hard tools are not allowed to scratch stainless steel sealing surfaces, preventing the decline of equipment accuracy or premature aging of components.
- Efficiency Balance Principle: On the premise of meeting cleaning standards, the cleaning process should be optimized to reduce downtime. For example, adopt a “zone-by-zone rotation cleaning” mode to achieve staggered connection between cleaning of some stations and production of others.
(2) Classification of Cleaning Levels
- Daily Cleaning: Applicable during production intervals, mainly to remove visible residues and dust on the equipment surface, such as wiping the outer wall of the hopper and cleaning debris on the conveyor belt surface. It can usually be completed within 1-2 hours without affecting the overall production rhythm.
- Deep Cleaning: Key components such as filling nozzles and sealing molds need to be disassembled regularly (e.g., weekly or monthly, adjusted according to production frequency) for thorough cleaning to remove stubborn residues in internal gaps and ensure the stable operation of the core functions of the equipment.
- Sanitary Disinfection-level Cleaning: For aseptic packaging production lines, in addition to basic cleaning, microbial disinfection is also required to make the number of colonies on the equipment contact surface meet industry standards, which is applicable to packaging equipment for high-risk products such as dairy products and medical supplies.
(3) Risk Area Identification
According to the degree of contact with products, it can be divided into three types of areas: direct contact areas (filling nozzles, sealing molds, material conveyor belts, etc.), which require the highest cleaning level; indirect contact areas (equipment splash areas, residue accumulation tanks), which are prone to bacterial growth and need key cleaning; non-contact areas (equipment outer surfaces, frame structures), which do not contact products but affect the overall hygiene of the workshop and need regular dust and dirt removal.
2. Cleaning Schemes for Components of Different Materials
(1) Food Contact Surfaces (mainly stainless steel)
Food-grade alkaline cleaners (1-3% concentration) or neutral special cleaners are preferred, combined with hot water at 60-80℃ for cleaning, which can effectively dissolve oil and protein residues. Soft nylon brushes, non-woven fabrics, or special plastic scrapers should be used as cleaning tools. Steel wire balls and other hard tools are strictly prohibited. At the same time, chloride cleaners should be avoided to prevent corrosion of the stainless steel surface.
(2) Seals and Rubber Components
Mild pH-neutral cleaners should be used, and manual cleaning should be adopted to avoid direct impact of high-pressure water flow leading to seal deformation. After cleaning, it must be thoroughly dried to prevent mildew; it is recommended to formulate a regular replacement cycle, for example, silicone sealing rings should be replaced every 3-6 months to ensure sealing performance.
(3) Electronic Components and Control Systems
Before cleaning, the power must be cut off and the safety lockout procedure must be implemented. A moisture-proof method of wiping the shell with a slightly damp cloth and removing dust with compressed air is adopted. Direct contact of liquid with circuit boards, connectors, and sensors is strictly prohibited. Key electronic components can be protected with protective films.
(4) Conveyor Belts and Moving Parts
An online cleaning system can be configured to realize automatic cleaning during production intervals; the balance between cleaning and lubrication needs to be maintained. After cleaning, food-grade lubricating oil should be added to moving parts such as bearings in a timely manner to avoid component jamming due to dryness caused by cleaning.
3. Machine-specific Cleaning Operation Procedures
(1) Vertical Form-Fill-Seal (VFFS) Machines
Focus on cleaning residues in the gaps of the forming mold, which can be removed with a special brush; the longitudinal and transverse sealing devices need to be cleaned of heat-sealing film residues with heated special degumming agents; when replacing materials, the hopper and feeding system must be thoroughly cleaned. For powder packaging machines, the pipeline should also be purged with an air gun, while for liquid packaging machines, the inner wall residues of the pipeline should be removed through cyclic flushing.
(2) Premade Pouch Packaging Machines
The gripper assembly needs to be disassembled to clean the pouch picking and opening mechanism to prevent residues from affecting pouch picking accuracy; the piston and screw of the metering and filling system should be disassembled and manually scrubbed; at the same time, the pouch mouth contact parts should be cleaned to avoid sealing failure caused by pouch mouth pollution.
(3) Vacuum Packaging Machines
Regularly wipe the vacuum chamber sealing strip and apply special maintenance agent to extend its service life; the oxide layer of the heat-sealing device should be gently polished with fine sandpaper; the oil mist filter of the oil-immersed vacuum pump should be cleaned weekly, and the vacuum pump oil should be replaced in a timely manner.
(4) Labeling and Coding Equipment
The glue system should be flushed with a special solvent before leaving work every day to prevent pipeline blockage; the print head should be soaked and unclogged with supporting cleaning fluid; at the same time, clean the guide rollers and sensors on the label conveying path to ensure flat label pasting and clear coding.
4. Standardization of Cleaning Processes
(1) Preparation Work
Implement the shutdown safety lockout procedure, judge whether to perform limited disassembly or complete disassembly of components according to cleaning needs, and prepare special tools, food-grade cleaners, and protective equipment (gloves, goggles, etc.).
(2) Five-step Cleaning Method
- Pre-cleaning: First, remove large pieces of residues by dry method to reduce cleaner consumption; 2. Main Cleaning: Prepare the cleaner according to the proportion and clean by soaking, spraying, etc.; 3. Rinsing: Rinse with water that meets water quality standards until there is no foam or residue; 4. Disinfection: High-risk production lines need to be treated with food-grade alcohol or hydrogen peroxide disinfectants; 5. Drying: Dry with compressed air or natural air to avoid water stains.
(3) Installation and Commissioning
Reset each part one by one according to the component installation list. After completion, conduct no-load trial operation to check the equipment operation status. Finally, verify that the equipment is clean and operating normally through the first-piece packaging sample inspection.
5. Other Key Matters
(1) Selection of Cleaners and Disinfectants
Alkaline cleaners are suitable for oil residues, acidic cleaners can remove scale, and neutral cleaners are suitable for precision components; food-grade alcohol and quaternary ammonium salt compounds are preferred as disinfectants. When using them, the concentration and contact time should be controlled, and operators should be well protected, and chemical storage should be standardized.
(2) Cleaning Verification and Record-keeping
Verify the cleaning effect through visual inspection (no visible residues, smooth contact surfaces) and white cloth wiping test. For high-risk products, microbial surface smearing tests are required; establish a cleaning log to record cleaning time, personnel, cleaner batch number, and abnormal conditions to facilitate traceability and process optimization.
(3) Industry Innovation Trends
At present, automatic cleaning has become mainstream. Packaging machines integrated with CIP (Clean-in-Place) systems can realize unmanned cleaning, and ultrasonic cleaning and robot-assisted cleaning are gradually applied; green cleaning technologies such as biological enzyme cleaners and water circulation systems are both environmentally friendly and cost-reducing; the Internet of Things technology can realize the traceability of cleaning parameters and intelligent early warning of component maintenance cycles.
In summary, the cleaning and maintenance of packaging machinery and equipment need to balance safety, efficiency, and equipment protection. Through standardized processes and scientific management, it can not only ensure product safety but also extend the service life of equipment, laying a solid foundation for the stable operation of the production line.
