How to perform preventative maintenance on liquid filling equipment. Part 2
How to perform preventative maintenance on liquid filling equipment.
Below is a practical framework you can adapt for Laub\Hunt’s machines operating in your liquid filling line.
Build a structured maintenance plan
Document the asset:
● Record model/serial numbers, configuration (nozzle count, metering type, caustic‑duty options), and operating parameters.
● Map critical subsystems: product contact path, tanks/hoppers, pumps, metering devices, nozzles, capper or downstream integration, conveyors, controls, pneumatics.
Create a preventive maintenance schedule:
● Break tasks into daily, weekly, monthly, and annual intervals, aligned with manufacturer guidelines and production intensity.
● Include special intervals for caustic products (e.g., more frequent seal inspection, verification of chemical‑compatible components).
Establish documentation:
● Maintenance checklists for each interval and machine type.
● Log sheets (paper or CMMS) to record date, person, tasks performed, findings, and parts replaced.
● Standard operating procedures (SOPs) for cleaning, lockout/tagout, and spill/chemical handling.
Assign responsibility:
● Operators handle routine cleaning, visual checks, and basic adjustments.
● Maintenance technicians handle mechanical/electrical diagnostics, calibration, and component replacement.
● OEM or certified service providers perform annual inspections, upgrades, and complex overhauls.
Daily maintenance tasks
Designed to keep the filler clean, safe, and ready for the next shift.
● Clean product contact parts:
● Flush the product path with appropriate cleaning or CIP solutions, based on chemical compatibility and regulatory requirements.
● Remove, clean, and reassemble nozzles, valves, and gaskets as specified in the manual to avoid residue buildup and clogs.
● Inspect for visible issues:
● Look for leaks, drips, or product pooling under the machine and around hoses and fittings.
● Check for unusual noises, vibration, or heat from pumps, motors, and gearboxes.
● Confirm that emergency stops, guards, and interlocks are intact and functional.
● Basic functional checks:
● Run a short test to verify consistent fills on sample containers; investigate any variance beyond tolerance.
● Check display indicators, alarms, and HMI messages and address any warning conditions.
Daily tasks should be quick and standardized so they become part of normal shutdown and startup routines.
Weekly maintenance tasks
Weekly activities go deeper into mechanical and pneumatic systems and fine‑tune performance.
● Mechanical inspection:
● Inspect belts, chains, sprockets, and couplings for wear and tension; adjust or replace as needed.
● Check nozzle alignment with containers, conveyor guide rails, and infeed/outfeed timing.
● Inspect fasteners and mounting hardware for looseness due to vibration.
● Lubrication:
● Lubricate bearings, cams, and other moving parts with the correct lubricant and quantity; avoid over‑lubrication that can attract dust or contaminate product areas.
● Pneumatic and utility checks:
● Inspect air lines, filters, regulators, and valves for leaks and moisture; drain water traps and replace filters per schedule.
● Verify operating pressures and flow for air and other utilities against specification.
● Product and environment specific:
● For caustic applications, inspect exposed metal surfaces, fasteners, and frames for early signs of corrosion or coating damage; repair or replace affected components promptly.
● Confirm secondary containment and spill trays are clean and functional where required.
Monthly maintenance tasks
Monthly tasks involve more comprehensive inspection, calibration, and component replacement.
● Calibration and performance:
● Perform formal fill‑volume calibration using gravimetric or volumetric checks on multiple containers and fill levels.
● Adjust metering system parameters (stroke length, pump speed, timing) to restore accuracy and repeatability.
● Document before/after readings and updated settings.
● Deep cleaning and inspection:
● Partially disassemble manifolds, valves, and metering components for internal inspection and cleaning.
● Inspect seals, O‑rings, gaskets, and diaphragms for swelling, cracking, flattening, or chemical attack.
● Check electrical enclosures for dust or moisture ingress and verify tightness of terminals and connections (following lockout/tagout).
● System checks:
● Validate sensor performance (level sensors, photoeyes, encoders, load cells) and adjust or replace if drifting.
● Review alarm history and recurring faults; investigate root causes rather than repeatedly resetting alarms.
Annual (or planned shutdown) tasks
Annual tasks are often scheduled during plant shutdowns or low‑demand periods.
● Overhaul and upgrades:
● Replace high‑wear components such as bearings, belts, seals, and hoses, even if not yet failed, based on hours of operation and OEM guidance.
● Evaluate upgrades (e.g., improved seals for caustic duty, enhanced controls, updated guarding) to improve reliability and compliance.
● Comprehensive inspection:
● Perform detailed structural inspection of frames, supports, and guards for fatigue, corrosion, or damage.
● Inspect tanks, CIP circuits, and piping for pitting or thinning where caustics contact metal; consider thickness testing where critical.
● Validation and documentation:
● Conduct full machine performance validation: speed, accuracy, changeover capability, and safety system testing.
● Review and update maintenance procedures, checklists, and spare‑parts strategies based on the past year’s data.
● Schedule OEM or certified technician visits for an expert inspection and recommendations.
Spare parts and documentation management
Effective preventative maintenance depends on having the right parts and information available.
● Maintain a critical‑spares list:
● Identify and stock components with long lead times or high failure impact (e.g., seals, valves, sensors, drives, PLC/HMI modules).
● Standardize:
● Where possible, standardize components (sensors, pneumatics, fasteners) across multiple fillers to simplify stocking and training.
● Recordkeeping:
● Track parts usage to refine stocking levels and to spot patterns in failures.
● Keep manuals, electrical drawings, and pneumatic schematics readily accessible at the machine or in a digital repository.
Training and culture
Even the best plan fails without trained and engaged people.
● Operator training:
● Train operators on daily checks, cleaning, basic troubleshooting, and when to escalate issues.
● Provide refresher training, especially after near‑misses, changes in product, or machine upgrades.
● Maintenance training:
● Train maintenance staff on OEM procedures, safe handling of caustic products, and proper use of test and calibration equipment.
● Continuous improvement:
● Encourage reporting of minor issues, near‑misses, and ideas to improve reliability; integrate this feedback into the maintenance program.
key takeaways
- Preventative maintenance is a proactive, scheduled program of inspection, cleaning, calibration, and part replacement that protects liquid fillers from unexpected failures.
- A structured daily/weekly/monthly/annual maintenance schedule dramatically reduces unplanned downtime, improves fill accuracy, and extends equipment life.
- For caustic chemical applications, frequent inspection of product‑contact components and corrosion‑prone areas is critical to safety, reliability, and compliance.
- Documentation—checklists, logs, and training records—is essential to demonstrate control, satisfy audits, and continuously improve the maintenance program.
- Investing in training, proper spare‑parts management, and periodic OEM service support yields a lower total cost of ownership and more predictable production performance over the machine’s life.
Contact us for more information about maintenance.
