Information about Hoists
When you need a hoist it is important to let us know the following:-
 What is the load you are lifting?
How often you will be using the hoist?
Describe the load.
What is the height of lift?
Will the hoist be fixed suspension or will it
travel along a beam?
Do you need single or two speeds?
What controls - pendant or remote?
What will be the power supply?
What is the environment like?
Are there any special requirements?
HANDY HINTS
Remember to always tell us as much as you possibly can about your intended
use of the hoist. You may also wish to refer to the Lifting Operations and Lifting
Equipment Regulations 1998 and any other legislative documents or guidance notes
relevant to your industry.
Make of Hoist
These days most European hoists are like modern cars and TVs, etc., in that
they are safe and they don't break down unless you abuse them. However when
you buy a hoist make sure that it is a well proven make with excellent local
spares and service backup as a guarantee may be of little use to you if the
spares have to be brought in from another country.
The Load
The Safe Working Load is the maximum load which can be lifted safely by
the hoist. Tell us the actual load you are lifting and do not round it up yourself.
Also tell us how often you will lift the load. We will then be able to propose
the most appropriate hoist type and model to suit your particular needs.
Hoist Duty
Duty rates range from light to very heavy and we are best able to advise on
this after carefully considering all of the other information you let us have.
Nature of the Load
Tell us as much as possible about the load, its size, shape and what it consists
of.
Height of Lift
This is measured from the hook in its lowest position up to its highest position.
If possible tell us the exact height of lift required.
Headroom
This is the distance between the hoist suspension point (top hook or runway
beam bottom flange) and the load hook in its highest position. Some hoists are
designed to be low/close headroom so that you can maximise the height of lift.
Speed of Lift
Many applications only call for single speed hoists but a two speed hoist
(fast/main and slow/creep) is essential where precise load positioning is required
or where the load is such that it is safer to avoid the initial "snatch" which
you get with main/fast speed. Some manufacturers now offer variable speed hoists.
Hoist Suspension
Hoists can be supplied with a top hook or eye for a fixed position suspension
but if the hoist is to travel along a beam then the options are push/pull travel,
hand chain geared travel or power travel. The cheapest option is push/pull travel
but this is not recommended over 1.5 tonnes and also the trolley tends to travel
in 'jerks" of one or two feet at a time so accurate load positioning is difficult.
Hand chain geared travel is smooth and easy but you will have hand chains hanging
down from the hoist and they may get in the way of things. Power travel is best
because the hoist travels with the simple push ofa button and you can have either
single speed or two speed operation.
Control
Most hoists are supplied with a low voltage pendant control which is a push
button box suspended from the hoist on a cable. The pendant can be any length
to suit the job. Alternatively, the push button box can be wall mounted in a
fixed position. Another option is remote control by either radio or infra-red.
Radio control is the more versatile but bear in mind that the operator does
not need to be in sight of the hoist to operate it so care should be taken to
ensure that the handset is only used by responsible people and with great care.
Infra-red requires line of sight between the handset and the receiver on the
hoist and this can be a safety feature but the receivers on the hoist have to
be cleaned regularly otherwise they get dusty and will not function. All controls
can be supplied with a key operated isolator switch for security and safety.
We recommend that all remote control hoists are equipped with a plug in pendant
as a backup for when the remote control fails.
Safety Features
Most hoists these days are fitted with overload protection preventing the
hoist from lifting in excess of its safe working load. Slipping clutches are
sometimes used for this purpose and they also prevent over hoisting and over
lowering. Limit switches also prevent over hoisting and over lowering. Where
hoists travel along a beam under power they can be fitted with travel limits
so that they can be prevented horn colliding with obstructions or with runway
beam end stops.
Environment
Indoor, warm and dry or outdoor, cold and wet. Is the atmosphere hazardous
requiring explosion or fire resistant measures. Is there a lot of dust or other
contaminants.
Enclosure Protection
Most hoists are protected to at least IP54 as standard covering most normal
environments but you may wish to consider additional protection for hoists which
are permanently outdoors. An outdoor hoist should also be fitted with a weather
protection canopy.
Electric Power Supplies
In the UK it is normal to use 400volt 3 phase supplies but some hoists
are available for use with 110volt or 220volt single phase.
Pneumatic Power Supplies
Most pneumatic hoists operate on a pressure of approx. 90psi or 6 bar but it
is important to realise that they need a reasonable volume of air supply to
operate properly. Typically hoists up to 2 tonnes capacity consume air at approx.
22 litres/second.
Chain Hoists / Wire Rope Hoists
Chain hoists are cheaper and usually preferred up to 2 tonne. Wire rope
hoists tend to be quieter, smoother and are generally preferred at 2 tonne and
over especially for long lifting heights and for heavy duty use. There are other
advantages and disadvantages and we will advise on these according to your specific
requirements.
If you would like details of our other products or for more information email Ian Watson or go to Information Request.
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