What is a hoist? Why is electric hoist used so widely? What are the types of hoists? Which to choose chain hoist or rope hoist? What is the difference and similarities of the two types of electric hoist? Read on.
Types of electric hoist
What is a hoist?
It is an electrically powered appliance that is used to lift, lower and even move heavy or awkward objects. They are mainly used to alleviate potential strain and injury on any person who needs to lift a heavy object or where the object is just much too heavy for a human to lift unaided.
Electric hoists are found in abundance across many different types of working areas, they are commonly used on construction sites, in warehouses, workshops, car maintenance garages, dockyards and large ships but there are numerous other places that they are utilized that you would not expect, for example, lifting large tree stumps out, or lowering a chandelier for maintenance and cleaning.
Types of hoists
As the name would suggest, hoists are devices used to lift or lower a load by using a rope or chain wrapped around a drum or lift-wheel. They can be powered by electricity, air pressure or by manual means. The component to which the load is actually attached to is called the lifting hook.
A basic hoist can be defined by two characteristics; the lifting medium it uses and its source of power. Regular hoists can use either wire rope that can be wrapped around a drum or something cylindrical, or a load-chain that is raised by a pulley and a profile to engage the chain in order to lift loads. The power supplied for hoists to lift weights can come from hydraulics, electrical or air driven motors. Despite the fact that hoists have been around since the 1800s, electrical hoists only came about in the early 1900s.
Hoists come as integral-package units or can be customizable. Integral-package units are cost-effective and can only be used for moderate applications. Customizable units allow for more access on the application of the hoist as a user can decide on which of the different parts he wants to use. However, these hoists are more expensive as compared to integral-hoists though they can be easily repaired and are more durable. The type of hoist a person selects depends on the application of the hoist.
Electric hoist
10 ton electric hoist testing video
Electronic hoists have an additional feature called the hoist controller that can have various features depending on the preset specifications. Some examples of such features can be for the hoist to automatically lift a load when a container is full or acceleration and deceleration of the hoist’s speed when picking up or putting down a load. They also supply the electrical energy needed for the hoist to function.
As compared to the various types of hoists, electrical hoists are the most economical as they are more cost effective and easier to repair. As compared to the manual hoist that would require extensive manpower to run it, electrical hoists save cost on man power and are more efficient. Hydraulic or pneumatic hoists have their own advantages as well but may have a tendency of needing repairs more often as compared to the electrical hoist.
Next we look at the workings of an electric hoist.
Initially the hoist is attached to a solid load bearing structure, such as a mobile gantry, jib crane or steel beam, or even just a robust, solidly anchored hook /eye. When secured the hoist’s chain system may be lowered using the powered control pad, close to the item which is to be lifted, this is then either fixed directly to the load if appropriate, but a further chain sling or web sling is often utilised as these can be located around the load about its center of gravity, this is to ensure a balanced lift that will not tip. The sling is then attached to the hoists chain hook and then you are ready to lift, slowly at first until you are certain of its stability.
Most electric hoists will incorporate some kind of safety mechanism to prevent loads slipping and overloading, which can be extremely dangerous. Hoists usually work with a clutch system, this allows the chain to slip at a preset torque which prevents any overloading. Some electric hoists the overload limit is operated via the chain mechanically engaging with a switch mechanism. Most modern hoists have safety cut out switches so that power can be cut instantly if there is a problem with the lift.
Why use an electric hoist?
There are a variety of reasons, the main issue is probably safety, as there use can hugely lower the risk of injuries; this is due to the fact that the hoist takes all the weight, not the individual, we all know how easy it is to strain your neck or back by incorrectly lifting even the lightest object. This brings us to the next advantage of cost efficiency, electric hoists are cost efficient because firstly they do the lift of what would have possible taken 3 or 4 men or more to lift, therefore reducing manpower needed, secondly as they greatly reduce injuries there will be less time off sick and so no reduction in manpower and no sick pay to provide. If your electric hoist is looked after then it should last a long time, any problems can usually be easily repaired, and a 6 or 12 monthly test and inspection should be carried out by a qualified engineer to certify its safety for use.
So it seems like an electric hoist is a cost-effective and much safer way to lift all types of objects, big or large, light or heavy, in all areas.
Types of electric hoists: Chain Hoist v.s. Wire rope hoist
Rope hoist or chain hoist, which do you chose for your material handling in your plant or factory? It a serious question for it may affect the material handling efficiency and hoist safety.
Misconceptions and bad influences on rope hoist and chain hoist
| No | Electric wire rope hoist | New type electric wire rope hoist |
|---|---|---|
| Capacity | 0.5~16ton | 1.6~12.5ton |
| Hoisting speed | 8m/min | 1.6,1.0m/min |
| Travel speed | 20,30m/min | 2～20m/min |
| Duty group | H3 | H4 |
Rope hoist and chain hoist have little difference
Rope hoist and chain hoist performs similar function but they are designed for different types of loads or materials. Therefore, when selecting an electric hoist, or upgrade and modernize your existing hoist, you need to know the rope hoist and chain hoist requirements and applications, etc.
Bad influence on selecting wrong type of hoist
Unnecessary expenses will be spent in the future when selecting wrong hoist. Wire rope hoist used unnecessarily will cost a higher price which can be avoided by using chain hoists for the latter is less expensive than a wire hoist with similar quality.
Bad performance and frequent maintenance will be required when selecting wrong hoist. For example, when you use a chain hoist when wire rope hoist is required, the hoisting system will performs badly and may requires more repairs frequently.
Rope hoist v.s. Chain hoist
Rope hoist
Rope hoist is widely used in in permanent, more stationary equipment, but they can still be used in hoists that are set up and torn down as needed. Rope hoists have a little more complicated application for there are several different types of rope hoists with various drum and motor combinations.
- Rope hoist uses grooved drums to increased accuracy.
- Rope hoist adopts multiple drums to compound strength.
- Different compound solutions for different requirements and problems.
Rope hoist is usually rated for heavier loads, on average, between 2 ton and 30 tons. Theoretically, the more your average load weighs, the higher the rated capacity you need, and more likely the rope hoist you will chose.
Rope hoist is also more proper for long work hours, when loads need be handled in short time.
Rope hoists are also handy in intense environments where there is extreme heat or harsh weather conditions.
Coins have two sides. As mentioned above, rope hoist is more expensive than chain hoist under most conditions. And also they are tend to be larger and more complicated.
A rope hoist system may not be practical or even possible for factory or workshop where the work room is limited. Generally, the rope hoisting system is used in factories, such as steel service, foundry, and raw material production facilities.
Chain hoist
Chain hoists is less permanent and easier to move around than rope hoists, which means the chain hoists are more flexible when adequate room is available or the necessary to switch positions when depositing loads.
Like rope hoist, the chain hoist capacity can vary but usually within a smaller range than wire. Chain hoist is ideal for lesser loads, where weight is not so much of a concern — typically within the 1/8-of-1-ton to 5-ton range. Rope hoists are frequently found in smaller factories, in maintenance work, and at workstations where lifting needs to be done.
Chain hoist also have the advantages such as ease of use and applications for jib, gantry, and hand-push cranes, which tends to involve manual movement load hooks, which wire rope hoists can slip out of more easily; whereas chain provides a greater level of dependability.
How to choose between rope hoist and chain hoist?
Even you know your capacity, have a good balanced choice between rope hoist and chain hoist, and the prices are reasonable close, there are also factors which will affect your decision.
Operator training
Hoist operator training affects the selection of the hoist system. Your worker may be familiar with one hoisting system and switching to a new hoisting system means new training cost, and the lower productivity that comes with inexperience.
Changing of load weight
On other circumstances, you may want to switch from chain hoist to wire hoist if you believe that you’ll be handling larger, heavier loads in the future and it might be good to prepare now instead of later.
Hoist brand
You may have a loyalty to a particular brand.
Besides the factors mentioned above, there may be other factors affect you to make a decision on selecting hoist system. We have a variety of chain hoist and rope hoist for you and offers free consulting services to help you to select the right hoist for you application.
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