With summer temperatures reaching record highs in many places, people around the world are finding ways to cool off. What better way to do so than drinking a refreshing beverage? Most of our favorite drinks come from cans. Every year, we use about 200 billion aluminum cans from beer and soda consumption. This comes to 6,700 cans every second - enough to go around the planet every 17 hours!
Have you ever thought about how these steel and aluminum containers are manufactured? The process is quite interesting with many steps … forming, trimming, cleaning, decorating, necking, inspection … but with any precise manufacturing, there are challenges. Using the right parts such as composites in canning applications CAN help!
Kicking The CAN Around: What Are Major Challenges For Manufacturers?
The technology that became the standard for the all-aluminum cans we use today was developed in 1963 by the Reynolds Metals company (fun fact: Reynolds later expanded into non-aluminum products such as plastics and precious metals, introducing Reynolds Plastic Wrap in 1982). The first companies to adopt this new can were Coors and Hamms Brewery with PepsiCo and Coca-Cola following in 1967. The number of aluminum cans shipped in the U.S. rose from half a billion in 1965 to 8.5 billion in 1972. Since then, the number continued to increase as aluminum became the nearly universal choice for carbonated beverages because it was not only lighter than old steel or steel-and-aluminum can, it did not rust, chills quickly, is easily imprintable, prolongs shelf life and is easy to recycle.
Today, the leaders in can manufacturing in the U.S. include Ardagh Group, Crown Holdings, Inc. and Ball Corporation. Did you know that Ball manufactures over 40 billion cans a year (at least a quarter of the world's total production)?
Portability, greater convenience, infinitely recyclable and the move from carcinogenic materials (such as BPAs) in packaging is leading to growth in the metal cans market. Demand for healthy drinks, carbonated drinks and juices is also a big contributor to this growing industry, valued at about $48 billion USD in 2018, and expected to surpass $58 billion by 2024, with Asia Pacific the fasted growing market and the US the largest, according to Mordor Intelligence.
Major can manufacturers often run around the clock producing cans to tight tolerances. It is not uncommon for multiple machines to produce the same or different size cans at various stages with outputs of three to four million cans per line per day. With such high production speed, these plants cannot afford downtime of even a few minutes as it can severely decrease productivity and increase costs. This is the reason they invest in equipment and parts that do not fail. Bushings, bearings and other parts in canning machines play a critical role since they are subject to long run times, high-speeds, vibration and extended wear.
Metal and bronze bushings and bearings are commonly used in canning applications due to their softer materials, which act as a sacrificial element to break down before mating parts do on large, expensive machinery and help to leave equipment intact. A downside of metallic bearings and bushings is they require a substantial amount of grease or oil to keep them lubricated. This lubricant, which is automated to flow through lines to machinery, can make surfaces, equipment and cans slippery and pose several challenges.
Simply ensuring the functionality of the automated lubrication system can be a challenge. Manufacturers constantly check the following to prevent equipment from freezing up and causing downstream problems:
- The proper amount of grease
- Functionality of the pump mechanism
- Proper flow of the lubricant, with the possibility for machinery to break itself and lead to outages if this is not adequate
Not enough grease is an issue, and too much is also a challenge. Issues that can result include:
- Safety risks – Grease getting into moving parts and onto products can make for unsafe working conditions. Too much grease poses a risk for slips and trips and runs contrary to the 5S methodology to efficiently and safely manage workspaces for work to be done.
- Increased scrap – Sophisticated vision systems, photographically examining cans for quality, may automatically boot those with grease from assembly lines. When one can is ejected, often several others follow, increasing scrap and assembly costs.
- Reduced life & increased downtime – Greater and faster wear to bronze and metal bearings and bushings creates a maintenance issue. This is compounded by the fact that many of these parts are used in difficult to access locations or in hot, hostile, environments, where they may be harder to reach and not be adequately lubricated, as a result, causing unscheduled downtime.
Critical Composite Parts CAN Make THE Difference
For these reasons, carbon fiber, composite bearings and bushings are on the rise as an alternative to bronze. These high-performance polymers offer high strength and can address high temperatures without requiring lubrication. While carbon fiber is very light, it is five-times stronger than steel and twice as stiff, making it suitable for many manufactured material parts.
Our Hycomp™ composite solution is a high-temperature resin polymer, milled carbon fiber and graphite bulk molding compound that is specially designed for higher speeds, medium loads and lower impact. This unique self-lubricating resin system is blended with carbon fiber to deliver superior wear, excellent dimensional stability and vibration dampening to improve canning plant operating efficiency. It can be compression or transfer molded to operate in 600° Fahrenheit (315° Celsius) conditions continuously. Reduced wear between moving elements also means better process control and improved quality.
Given its benefits, the composite is used by the above-mentioned three major can manufacturers as well as OEMs like Stolle, Belvac, Carnaud, and others. It is used in bearings, bushings and other parts in machinery in all stages of can development, from shell press, to body making and trimming, IC spray decorating and necking.
Specific advantages of composite bushings over conventional high pressure, hydrostatic, bronze bushings include:
- Dry running – Grease lines, line pumps, and chambers can be removed, drastically reducing safety and productivity hazards and increasing can throughput. Composite bearings can often run completely dry, or with minimal manually applied grease.
- Reworks are reduced – A good example of this is at a Crown Cork and Seal site where standard Necker Ram Housing reworks with composite bushings run six to eight years, which is significantly more efficient than the two to four years for OEM product runs. Rework costs are generally less for composite bushings than with OEM components.
- Longer life and reduced tool/die wear – The stable material in composite bushings ensures good wear life as a result of a microscopic resin transfer that gets into the mating surface finish when being broken in to reduce the amount of abrasion on devices.
- Better alignment and productivity – With vision systems for quality detection extremely sensitive, misalignment of even a fraction of a hair on canning machines due to wear can pose a large downstream risk to metal cans. Since bearings wear significantly less over time compared to metal or copper bearings, they can maintain alignment longer to help ensure quality.
As mentioned, one specific application where Omniseal Solutions™ bearings and bushings are valuable is in the necking machine. The neck of the aluminum beverage can, from which one drinks, is formed in 14 stages using a tool that extends and retracts on the end of a shaft through a housing to slowly develop the thin aluminum wall to prevent cracking.
The necking machine runs around 3,000 cans per minute and is a major bottleneck. Each housing rotates on a turret with a shaft in each chamber. A tool on the end of the chamber extends out, timing perfectly with a can as it goes by to put a little bit of the neck on each time. Typically, the OEM housing/shaft is metal on metal wear interface and needs lubrication pumped in. With as many as 24 housings and 14 turrets all getting grease, the lubricant can get extremely messy, coating the inside of the machine cabinet and sometimes getting onto cans being formed, leading to increased scrap.
Omniseal Solutions' team developed a solution to vastly eliminate requirements for grease in this application. With housing on this machinery being removable, their team bore out the housing ID where it press-fits in composite bushings. This becomes the new, longer-wearing surface for the shaft. With bushings being dry running, the need for grease is greatly reduced and the life of the housing system is extended from two to three years with most OEM systems to six to eight with the bearings.
Other specific applications for composite bearings and bushings include:
- Body makers - Replacing conventional high pressure, hydrostatic, bronze bushings for tighter running clearances and better vibration dampening protection of the ram. The result is better looking beverage cans, reduced tool pack wear and a reduction in oil consumption, improving processing efficiency.
- Vacuum manifolds - Offering stability and dramatically reduced wear to extend service life, reduce downtime, and increase productivity in this sealing equipment.
- Shell presses – Providing as much as 20 times longer life than nylon and PTFE-based products. Composites also do not creep to help maintain critical clearances between moving parts.
The Right Experts CAN Also Make THE Difference
Worldwide production of aluminum beverage cans is growing by several billion cans a year. With this rising demand, the future of the beverage relies on designs that save money and materials. Can manufacturers need to work with the right partners and the right parts. With longer life, reduced wear and dry running capabilities, Omniseal Solutions' composite bushings can help canning companies achieve critical tolerances for longer service and less scrap. Their team of experts have many years of experience solving challenges and creating custom solutions.
Founded in 1986, Cleveland, Ohio-based, Saint-Gobain Hycomp is a premier supplier of composite parts made of injection and compression molded engineered thermoplastic and thermoset materials. It was acquired by Omniseal Solutions™ in March 2018, complementing its high-performance sealing and polymer offerings for high temperature and high load materials. Solutions were initially developed for wide-scale aerospace and niche areas worldwide, including for use in aggressive space applications that can run constantly at 600° F (316°C) with no lubrication and without breaking down for NASA.
Omniseal Solutions™ operates from a fully-accredited ISO 9001 and AS 9100D facility and has implemented a fully-operational test laboratory and quality clinic to ensure the highest standards and continuous improvements. The business also supports the industrial industry with its Wearcomp® carbon fibers that is used in extrusion, rolling mill and shear applications.
Together we CAN improve your manufacturing efficiency. Contact us today for help with these critical canning applications!
