The Vibration Isolation Design Manual for Marsh Mellow® springs details how and where to use the fabric-reinforced solid rubber isolators for quiet isolation of machinery vibration and for general shock absorption throughout industry. The cylindrical springs developed by Firestone - the world's number one producer of air springs (or airbags) for isolation and actuation - are used world-wide for applications involving vibration isolation in commercial and industrial buildings, construction, electrical, automation and electronic processes, process and production engineering, forestry and primary production, manufacturing (inc food, metal and general), metal processing, materials handling, mining and mineral processing, including conveyors, oil and gas processing, packaging and worker safety.
Marsh Mellow springs are particularly suitable for vibration isolation of machinery such as:
- Automation technology (either isolating such technology, or isolating surrounding machinery)
- Bin hoppers
- Blowers and motors
- Compressors
- Conveyors
- Generators
- Stamping equipment
- Vibrating screens
Marsh Mellows give consistent performance regardless of changing loads, while offering high lateral stability and compact size, says Mr James Maslin, Sales and Marketing Manager for their Australian distributor, Air Springs Supply Pty Ltd, which has a nation-wide sales and service network, established for more than 30 years.
The new manual - which includes both Imperial and metric selection guides - also details shock absorption applications in cranes, hammers, bumpers and similar applications requiring the cushioning of a violent blow (such as conveyor stops in industries as diverse as packaging and logging). Marsh Mellow springs are constructed of a solid rubber core with a hollow centre and several plies of fabric-reinforced rubber as an outer cover.
The plies provide the springs with stability as well as a consistent cylindrical shape, says Mr Maslin, whose company distributes both Marsh Mellow isolators and Firestone Airstroke™ and Airmount™ bellows-type, air springs (also known as airbags) throughout Australia. "The low natural frequencies of Marsh Mellow springs mean they provide excellent isolation of forced frequencies in the range of 800-1200 cycles per minute (13-20 Hz)," he said.
"Marsh Mellow springs are quiet in operation, unlike steel springs which readily transmit high frequency structural noise and often suffer from coil chatter. A failing coil spring may crack, causing fragments of the coil to damage equipment, resulting in expensive downtime. This problem is eliminated with Marsh Mellow springs, which are tolerant of overload and, if they ever do fail, do not fail catastrophically. "Their high load capability means fewer springs may be needed in an application, resulting in less overall cost," said Mr Maslin.
Marsh Mellows' fabric-reinforced spring has more lateral stability than an all-rubber spring of the same size, so it can support greater loads while maintaining its cylindrical shape. A spring with a smaller overall size than an all-rubber spring of identical load capacity can be chosen, which is an important factor where space is restricted, says Mr Maslin. Marsh Mellow springs range in size from the 0216 model with an unloaded height of 44 mm and outside diameter of 41 mm, through to models such as the 0243 with an unloaded height of 203 mm and an outside diameter of 279 mm.
Marsh Mellow springs are maintenance-free. They have no moving parts and require no lubrication. Their rubber and fabric-reinforced construction is corrosion resistant for a durable, long life. Marsh mellow springs have been proven in the damp and corrosive environments of mines and mills where standard coil springs may suffer premature failure.
