Do you know your cranes? There are actually four main types of overhead cranes but you will need to know exactly what they are for.
Today we will look at the difference between a jib crane and a gantry crane. These two overhead cranes are rather different and can be used in very different situations.
How Cranes Work
Before we look at the differences between these two crane types, let’s consider how a crane works in the first place. It’s quite the feat of engineering to create a long pole that allows heavy materials to lift and move around.
Cranes involve pulley systems to ensure there is enough force to lift the load. Pulleys can be used together to create an easier method of moving items. They’re considered simple machines, but there’s nothing simple about a crane.
The crane’s vertical pole is called a boom and at the far end is the main boom tip sheave. The main load line runs through this and has another sheave on the opposite end of the line, in the load block.
The load block has a hook set into it so it can hook onto the load that it is supposed to lift. To prevent the main load line from snapping with all the weight it needs to lift, the crane uses multiple pulleys so the load weight spreads out and is not all in one area. It also utilises support cables to ensure everything can be supported properly.
Along with this, the hoist is moved up and down the boom and it may also be balanced on the fulcrum so it uses the power of a lever to ensure it can lift some pretty serious weights. Large cranes may lift up to 40,000 lbs.
The cranes we’re looking at today do use simple machines to work, but they’re less movable. The arm or bridge is set and the actual hoist moves back and forth and up and down, running on tracks.
What is a Gantry Crane?
A gantry crane is designed like a frame, so they’re actually quite different from a regular crane that you would imagine. This frame or bridge has two legs that are set on the ground. They may be equipped with wheels or you can slide the entire piece to another area or they may be bolted in place.
Others are set into a track on the floor to ensure they move in a straight line.
The actual gantry crane slides back and forth horizontally on a track on the crosspiece of the bridge. This allows it to lift an item and move it over to another position horizontally.
Gantry cranes are often used on construction sites because they are so portable and simplistic.
If you have a repetitive job that requires lifting and moving something a little, you’ll find that the gantry crane is very useful. It’s often used for loading trains, lorries, and other things where it can be set up over the platform to be loaded.
Gantry cranes tend to use chains as the hoist more often than jib cranes.
What is a Jib Crane?
A jib crane is a permanently installed crane over a specific work area. It looks like an upside-down L, with the arm or boom leaning over a workstation. A wall-hung jib crane can only move 180° as the boom rotates, but if it is a mast-type jib crane, it will swing completely around, often moving items to other workstations.
Jib cranes are very easy to install and are good for the precision placement of loads. They use roller bearings in the overhead track to provide very smooth operation and they will last for a long time with minimal moving parts.
These cranes may be used below larger bridge cranes if they are used outdoors on loading docks. Sometimes, one jib crane services multiple workstations, but you can also set up multiples that overlap to create a fully working hoist and crane system.
Jib cranes usually use an electric hoist.
Where to Find a Hoist and Crane?
At this point, you likely have a good idea of whether you need a jib crane or a gantry crane. Both are quite useful but in their own ways. You’ll need to be sure you check the following before you purchase or hire one:
Weight rating: Depending on the loads you’ll be lifting; this could be a very important factor. You want a crane that will be able to hoist everything you need without straining. The weight is also a factor as it can cause the crane to become unbalanced if it is over the recommended weight.
Range: This is particularly important with the jib crane, as you’ll need to know how far it can swing. This will determine if you need more than one or if just one will do the job.
Hoist type: Chain hoists have fewer issues than electric hoists and you can easily fix a chain hoist. More can go wrong with the electric one. Check which type of hoist is being used for the crane.
Size: Since cranes come in a range of sizes, you need to be sure that you have what you need. Check the size and then look at how much height you can use if the crane will be indoors.
Mobility: Can the crane be moved? Both jib and gantry cranes may be moveable and if you need the ability to switch things around, this is going to be very important.
Any type of hoist and crane can be very useful in the workplace, but you do need to choose the one that will best suit your needs. If you’re still not sure what to choose, contact Crane and Lifting. We’re more than happy to let you know how to use our cranes to their maximum potential. Let us help make your workplace a more efficient space with our cranes.