The heavy mob
12 February 2009Hoist doesn't publish an editorial features list, for a number of good reasons. So, I get the question quite a lot: what's coming up in the next issue? Well, here's a sneak preview of March.
When loads are heavy or need to be lifted particularly high and sometimes around the clock, heavy duty open winch (or 'built-up' in the States) hoists come into their own. I've spoken to a handful of manufacturers, on both sides of the pond, about their take on heavy or specialist lifting. There's some good pictures too!
True, series built electric wire rope hoists have revolutionised the crane industry. They are the automatic choice for most mainstream applications. However, the range covered by these pre-engineered products is inevitably limited to the most commonly occurring applications and they are not suitable for every situation.
Where cranes are subject to arduous conditions - heavy lifts, high intensity operations, frequent motor starts, high speed of operation or greater height of lift - then heavy duty open winch hoists fit the bill.
Equally, there are some industrial processes that have complex and unusual handling requirements, such as dual or multi-point lifting or very special safety needs, thus, excluding standard hoists.
The biggest markets for open winch hoists are the USA and Canada, where they are commonly referred to as built-up hoists.
The open design provides for easier assembly, inspection and maintenance and avoids crowding of the components for better cooling. This may be especially significant where the hoist is used in hot applications such as handling ladles, castings or ingots. The open plan design also allows for an almost unlimited combination of components to provide customised solutions to individual lifting applications. This is especially relevant when the crane is integrated into a particular industrial process allowing special equipment such as grabs, magnets and other lifting devices to be incorporated.
As Al Horgan, Whiting crane application group supervisor, says, "the heavy industrial manufacturer will typically require a more robust overhead material handling system, wherein the crane becomes an essential and integral part of the facility's production throughput." Minimising downtime and maximising reliability and maintainability are major considerations in the purchase of such heavy duty units.
Just a taster. More in the March issue.
Richard Howes, Editor
