There are some jobs out there that your strength and ingenuity can’t handle and because of that, you have to hire some heavy-duty machinery. This article today will discuss that. If you have a very tall, bulky, heavy load you need to transport from point A to point B or load it on something, you probably need a crane to do that.
What type of crane and for what job you need one depends on several factors?! What you need to do in the beginning is check all measurements before you hire a crane and before it arrives at your site. By doing this you are ensuring that the crane can safely fit where you need it and that it can do its job effectively.
There are different types of cranes you can hire and today we are discussing grab cranes. There are several types of those as well and we will talk a bit about each and tell you what and how you can use it for. Many companies offer their cranes and one of those is Uniforest which also has a range of cranes that might interest you so if you are in need check them out.
What is a grab crane first of all? It is a machine that can automatically pick up and release the desired load and they are classified as bridge grab cranes, folding arm grab cranes and gantry grab cranes.
1. Bridge Grab Cranes
Now as the word suggest this is a bridge design grab crane that has a bridge-like construction on top and a single or double beam that holds the grabbing bucket which is set beneath it and is suspended by a single or double rope that is supposed to lower the bucket and bring it back.
There are also electric grab and target set grab bridge cranes that are used more and more, again, depending on the needs and application The bridge cranes are fixed and they move forward and backward on a fixed rail and the bridge part allows for the bucket to be moved left and right.
These types of cranes, depending on the grab bucket and the needs are usually used for picking up bulk and granular materials. It can be used inside and outside and the total lifting weight includes the weight of the grab. The best thing is that these types of cranes can be configured to your need but only according to the manufacturers’ spec and recommendations.
2. Gantry Grab Cranes
These types of grab cranes are similar to the bridge ones. The similarity rests in the overhang part of the crane or the bridge part. With the previous type, the bridge part is mounted on the beams while the gantry type grab crane has feet of sorts. Gantry type cranes have beams that are on the ground but again moving on the rail that has a fixed trajectory.
So it can go forward and backwards and the overhang part of the beam that is holding the grab part of the crane is moving right to left. These types of cranes are mainly used outdoors and most of them can be seen in ports and they serve as a heavy load transport, from containers to coal wood, etc. its utilization depends on the needs and the type of the grab bucket installed.
These are made and used for a means of very heavy load transport and, as we stated you will see most of these in ports transporting containers from one position to another or loading those on top of transport trucks or trains.
3. Folding Arm Cranes
Now, these are probably most familiar to most of us since these types of cranes are either mobile or partially or entirely fixed. There are several types of these as well but we probably know the best those mobile folding arm cranes. They come as an attachment for a piece of machinery or they come as a whole machine.
This depends on the purpose and the amount of weight it can and needs to lift. Probably the simplest grab crane with a folding arm can be found on the back of logging trucks and those are used for log loading. Those bigger and capable of lifting more weight come as a self-propelled machine that needs time to unfold and start its job.
These types of cranes that have folding arms can be utilized for almost anything and the range of grab buckets is more versatile. After we divided the grab cranes into these categories we should also mention that you can classify these according to what it uses to load the materials. We mentioned some of these already but let’s go through them again.
Clamshell type grab crane
This is mostly used for loading huge amounts of materials, different minerals, coals and materials like gravel, earth, stone, sand etc. You can find these in ports, docks and similar places and they are really neat when you want to transport big amounts of material fast. Thanks to its construction it got its name clamshell because it closes on both sides just like a clam shell and encloses the material until it’s time to open up and unload.
Multi petal grab crane
This type of grab crane is pretty interesting and it draws your attention. It is built like an orange that you started to peel from the top down but didn’t peel all the way through. It uses hydraulics to open and closes the petals and grab on to materials that are a bit bigger like scrap metal, scrap vehicles, or waste materials.
If you are trying to picture this type of grab crane remember any movie that had a scene at the scrapyard where it needed to transport a scrap car to the crusher. The thing that lifts it with those metal fingers is exactly this orange peel grab crane with multiple petals.
Grab cranes that are suited for wood, logs, and straw bales
These types of grab cranes can be used to pick up wood, logs, bales of straw and anything in between and they are mostly variations from the previous two ones and are very well adapted for these types of work.