As companies using loud stamping, screening and metal forming equipment become more aware of workplace noise and vibration hazards, their managers and engineers are seeking solutions to problems posed by unruly coil springs.
Not only is noise an issue with a wide range of industries, including food and packaging, manufacturing, mineral processing, materials handling and quarrying, but also they are concerned about the possibility of fragments from broken coils, finding their way into delicate equipment or production processes.
It does not matter whether you are a heavyweight mining, quarrying or manufacturing operation, or a delicate food and packaging operation, companies today just cannot afford workplace hazards or production shutdowns, according to pneumatic actuation and isolation specialists, Air Springs Supply.
Air Springs Supply is introducing expanded ranges of ruggedly compact and highly efficient Marsh Mellow isolators that tame vibration, and eliminate damage and production interruptions caused by coil spring breakages.
Firestone Marsh Mellow springs are engineered for immense strength and longevity with hollow centres, surrounded by a solid rubber core and fabric ply reinforced body, to deliver constant vibration isolation with changing loads. Their unique construction delivers low natural spring frequencies to provide isolation of forced frequencies in the range of 13-20-HZ (800-1200 cycles a minute).
This outstanding performance, and a maximum load range now extending from 1.4 kN up to 88 kN (on special order), makes them particularly suitable for vibration isolation applications beneath such equipment as bin hoppers, compressors, crushers, blowers, motors, HVAC installations, stamping presses, metal stamping lines and vibrating screens.
Marsh Mellows also make ideal shock absorbers for conveyor, steel product, timber product and other materials handling applications, particularly in mills and mines, where their corrosion-resistant durability means they will survive damp and corrosive environments, where standard coil springs may struggle and prematurely fail.
Marsh Mellows have no moving parts and require no maintenance or lubrication, so they are ideal of applications in grimy and demanding environments such as mining and resources, bulk materials handling, manufacturing, metals and primary product processing. And because they reduce structurally transmitted noise caused by vibration, Marsh Mellows have considerable OHS and comfort benefits by being quiet in operation, unlike coil springs, which often suffer coil chatter and readily transmit high frequency structural noise.
Their terrifically rugged rubber construction eliminates the problem with coil springs of cracking to allow fragments of metal to damage equipment. Additionally, Marsh Mellow springs exhibit exceptionally high overload characteristics, and offer some support even during eventual failure.
Another major advantage, from an engineering viewpoint, is their low compression set of only up to 7 per cent over time. This low compression set is important in applications where it is critical to maintain design height.
Other advantages of marsh Mellows include:
High load carrying capacity because of their superior deflection capabilities and the load carrying influences of the fabric reinforcement. This means they can carry a greater load than an all-rubber part of the same modulus and dimensions at a superior natural frequency.
Increased stability at higher percentages of compression. As height compresses, the fabric-reinforced rubber plies pantograph and the diameter grows. This supports the rubber core laterally even in an emergency at 30-40 per cent compression.
Lower cost. Marsh Mellow springs’ higher load capability means fewer springs may be needed in an application, resulting in less overall cost.
The spring’s components (rubber, bias plies, size of centre) are combined in different ways to meet specific load and performance requirements. This gives them great flexibility and precision.
Naturally different types of springs have different performance characteristics suited to particular tasks. These should always be discussed with suppliers having wide experience in the particular area of application being considered.