The aerosol manufacturing industry has come a long way since the introduction of “bug bombs” during WWII. To meet today’s high demand for aerosol products, assembly lines must produce copious volumes in a wide variety of packaging, while upholding high standards of safety and quality.
Any product defects—including split gaskets in valves, pinholes in cans, molding flash on valve components, and clinch or crimp failures, and others—must be detected and immediately eliminated to prevent leakage of potentially flammable or otherwise dangerous substances.
Contrasting with hot water bath systems, our article in the July/August 2023 edition of World Aerosols, titled Laser Spectroscopy Microleak Detection Systems Enhance Aerosol Production Efficiency and Product Safety, showcases the benefits of laser-based microleak detection systems.
Early leak detection systems consisted of operators manually observing aerosol cans immersed in hot water baths, which they meticulously examined for the presence of bubbles, indicating leakage. As industrialization progressed and production line speeds continuously increased over time, automated water baths began to replace human observers, but issues remained.
However, even with automated monitoring systems in place, water baths have several drawbacks, requiring:
- high expenses to buy and install, about $250,000+ USD.
- a large footprint in space-constrained facilities.
- significant energy investment to maintain continuous water heating above 50°C/122°F.
- frequent maintenance and expensive chemicals to avoid corrosion and keep the bath clean.
With all these disadvantages, an effective alternative providing higher throughput with improved leak detection and safety is an attractive prospect. Modern quantum cascade laser-based systems address these and other issues, as you will see in the following applications.
Lubricant manufacturer brings aerosol filling in-house, and contract filler increases production rate
A lubricant manufacturer previously partnered with an aerosol company to package its products, but high defect rates resulted in 2.5 to 5% product loss, prompting the manufacturer to move its filling process in-house.
With limited space and a desire for superior performance, the company opted for Emerson’s laser-based Rosemount Aerosol Microleak Detection System, rather than a hot water bath.
This system is capable of detecting, identifying, and rejecting faulty cans at very fast line speeds, 300 cans per minute in the case of the refrigerant packaging system. It does this by drawing in the air around an aerosol can while it passes through the sample arch, directing the air through a measurement cell, and focusing a laser beam through the sample gas, which is reflected to a detector. Variations in light intensity are measured, and the leak rate is then calculated using infrared spectroscopy. If the leak rate is above specification, the product is automatically rejected.
- Air extraction arch: draws the air from around the aerosol can into the sample handling system
- Air filter: used for the removal of air particles and leaked contents of the aerosol cans
- Sample cell: laser light is directed through the air extracted from around the cans and back into the sensor head.
- Sensor head: contains the lasers and laser light detector. It is rated ATEX, IECEx and UKEx Category 3 for use in Zone 2, and for use in Class 1, Division 2, Groups A, B, C, & D, T6.
- Conveyor belt: used to transport the aerosol cans
- Automated can rejection/pusher mechanism
- Rejection bin
The system meets stringent safety and quality regulations without the drawbacks of water bath systems, while additionally providing diagnostic insights that enable the manufacturer to optimize its packaging process. Installing the system cost $200,000 USD less than a comparable water bath solution, and the company saves an estimated $35,000 each year in energy, consumables, and maintenance costs.
For contract fillers that specialize in filling and packaging other companies’ products into consumable aerosol forms, moving at high speeds while upholding safety and quality requirements is critical to success. One such filler installed a Rosemount Aerosol Microleak Detection System, which eventually replaced their water baths, to provide quality assurance for a range of product lines at a speed of up to 220 cans per minute.
The contract filler collects and analyzes batch performance data provided by the system to optimize production, identify problems, and implement proactive maintenance practices. These advantages empower the contractor to take on higher production demands, without compromising product quality or human safety.
Laser-based systems improve efficiency
Modern microleak detection systems are more than just quality gates as they enable aerosol packagers to monitor production performance and identify issues as they develop, significantly reducing faulty products or upstream machine failure. These capabilities help grow profits, boost company reputation, and elevate environmental sustainability, all while maintaining quality and safety requirements during high-speed production.
To find out how Rosemount’s Aerosol Microleak Detection System can improve your packaging workflows, consult with an expert on the web at Measurement Instrumentation Contact Us | Emerson (emersonautomation.com)