There is always room for a hoist in any factory environment and this favourite piece of equipment has become the work horse of many production lines.
There are, of course, a variety of brands capable of numerous tasks and available at prices to suit all pockets. But other products or components can be added to your hoist to increase its efficiency and your productivity.
Without doubt radio control, either alongside or instead of, pendant control has been one of the most successful add-ons. It can be fitted cheaply and quickly to the majority of hoist units on the market today.
The exception is the hoist units using ‘mains switching’ as a means of control, though these are now few and far between. Radio can still be used here, but this type of unit requires low voltage control gear to be installed to the hoist unit before it can be used.
Once radio is installed there are then two independent means of control, and in the unlikely event of the radio failing, it is a case of simply unplugging it and plugging in the pendant. Control of the hoist is then maintained and the cost of down time is minimised. A large percentage of breakdowns to hoist units are caused by pendant failures. A cable hanging down is extremely vulnerable to operator misuse and environmental hazards. With radio there are no hanging cables, fewer breakdowns, and so lower downtime costs.
The benefits of radio are numerous. The operator can move freely in his or her work area to get the best view of the load, no longer tied to the same spot as the pendant. This can only improve safety and efficiency.
Take for example the use of a hoist to dip materials into tanks. Hoists working over dip tanks very often require pendant extensions, but these have inherent problems. If the operator pulls the pendant it can lift the drive wheels off the beam and loses traction. Using a hoist on a runway with a switch point, and then tipping, can be a problematic, affecting smooth operation of collectors. The liquid used in the dipping process is often unpleasant and can have nauseating effects on the operator. All of these problems can be overcome by using radio.
Radio systems are used for many special applications allowing the use of two or more hoists at the same time. This achieved by:
Catch release – a mode enabling two or more operators to use one radio transmitter each to operate the same crane/hoist
Tandem operation – this option allows two cranes/hoists to be operated together using only one transmitter
Feedback systems – a feedback system allows information from the hoists (such as weight on the hook or speed of travel) to be read via an LED display on the transmitter
Unique address codes – these prevent cranes from being used inadvertently by another transmitter.
The disadvantages of radio lie in the initial set-up costs. It is fair to say that many radio systems are priced at less than many hoist units. However, the added efficiency and reduced maintenance needs they give to the life of a hoist, combined with low failure rates, means that these costs are soon recouped. Moreover, as with all equipment, the handset is only as good as the operator using it, so training in use and care is highly recommended.
In addition to radio control, the use of load monitoring equipment has now become mandatory for all new units. In today’s factory environment with increased awareness of the need for safety, this type of equipment should be allowed for when refurbishing existing equipment.
If required, digital load displays
can be fitted to lifting equipment so that the operators can clearly see
the load level that is being worked with. Fitted as an integral part of the hoist equipment, 2% accuracy is typically achieved.
There is an array of this type of device: load guards, analogue/digital craneweighers and load pins. Such equipment is practical and reliable and adapts to the varied and difficult working conditions found in factories.
The use of inverters offering variable hoist and travel speed option is also a practical way of protecting the brakes and drives of the equipment. One final option that some manufacturers offer is the use of condition monitoring devices, which asses the use and duty of hoist units.
All of these measures, coupled with regular maintenance, go a long way to improving the life expectancy of hoists.
