Construction Crane

Though all of us have seen construction cranes before, few of us know how they actually work. This is useful base knowledge to have when you’re looking at buying or renting a crane for the purpose of building a building or buildings.

First of all, let’s narrow the field. The construction cranes we’ve all seen are nearly always the kind of crane known as a ‘tower crane.’ That’s the one with a tall central shaft with a long boom and counterweights. Tower cranes are often built on-site and are even affixed directly to the structure of the building, especially in the construction of very tall buildings like skyscrapers. Take a drive downtown in any growing city and you’ll see tower cranes affixed to the tops of twenty-story office buildings going up. The most common point of affixation for these cranes is the concrete elevator shaft in the center of most buildings, but other points can be used as well if necessary.

Cranes can be put up in different ways. One of the most common, especially with the massive tower cranes used in industrial and large scale commercial building construction, is to use a second crane which is taller and lighter to hoist the crane into position. Some cranes can also self assemble, lifting off the ground with hydraulic jacks so the next section of the tower can be set in place underneath.

Standard process in construction isn’t buying cranes. Construction cranes and tower cranes are very expensive, and to simply buy one would be far more than needed by any but the largest construction corporations. The far more common case is to simply rent one. There are plenty of companies out there who make their profits by buying cranes and then renting them out to construction contractors for use in large scale construction sites.

On the other hand, some construction contractors may find it useful to buy a smaller crane. Some cranes are mounted on vehicles and can be used very effectively in relatively small projects – two story office buildings or large homes, for instance. These kinds of cranes vary greatly in price, but you could expect to pay anywhere from $20,000 to $100,000 for a good truck mounted construction crane.

When it comes to the big tower cranes, though, you’ll go to the crane industry and the crane companies who profit by renting their cranes out. It would be a good idea, if you’re interested in renting, to get online today – these days most companies, including any given crane company, probably have websites available to the general public online. If you’re looking to find a good crane company, looking for one online may well be the best option to finding the best deal for your money.

Though the more common option is to rent a crane for a specific job, some contractors and construction company owners may find it very useful to actually buy one and use it from construction type to construction site. Again, the internet can be an invaluable tool here, for many reasons. The most obvious is simple things like consumer reviews. Whereas a few years ago it would have been very difficult to talk with other people who’ve used the equipment you’re interested in, the internet today makes that much easier. If you want, you can read consumer reports and customer reviews. You can also get on forums and online construction message boards and talk with other professionals in the trade about what sort of equipment you may want to use over the course of a large construction project.

You can also outright shop for big cranes online. Some web sites are designed specifically to sell cranes of all sorts. You can browse not only through tower cranes, but also through vehicle mounted and other kinds of cranes in order to find the best construction crane for your business. Find the right crane company, and you find the best solution for your work site. Online websites can help you compare rates and specs. Some even link directly to consumer reviews of the equipment you’re interested in buying.

As we’ve stated before, the more common route in using construction cranes or tower cranes in construction is to simply rent the best one for the project you’re currently working on. So how do you find where to rent from? How do find someone who just happens to have a few six ton tower cranes on hand to lend to you for a few grand? Simple. Like buying cranes, the easiest way to rent one is to simply look on line. Each crane company, if it’s up to par with modern technological standards, will advertise online and have its own web site for you to check out and compare rates on.

Like buying cranes, you can find more or less any crane for any type of job. The difference, of course, is that you’re only paying per site. So, if your company does a wide and varied range of construction, you’ll probably be better off just renting a crane for specific instances and jobs. If, on the other hand, you specialize in one or another type of construction, you may well be better off just buying the right crane for the job and using it on each site you work at. It’s up to you as contractor – just do your homework before hand and make sure you’re well educated as to crane technology and your options before you make a deal.

The crane industry is designed, obviously, to lift stuff up. The problem is, of course, that there is a lot of stuff out there, and a lot of different ways to actually lift it up. You’ll find very quickly as soon as you start looking that there are a whole lot of construction and crane techniques out there by which any good crane company can learn how to lift something. It’s important to know the exact requirements and specifications of a construction job before you start looking for cranes to do the job by. Don’t forget simple measurements. How tall is the building, and how much taller than that will the crane have to be? Will it be mounted on the ground, or bolted directly to the superstructure of the building you’re trying to raise from the ground?

Depending on the site, there are a lot of things you can do. For relatively small, light loads that don’t require a lot of height, you can probably just use a vehicle based crane. These use several different techniques to lift things off the ground. Some have telescoping crane arms that can extend from a weighted main vehicle body in order to lift relatively small loads. On the other hand, gantry cranes can lift enormous weights, and can be moved around on rails. These are the most commonly used type of crane in shipyards and ports, simply because they can be used and are perfect for lifting cargo onto and off of container barges.

There are certainly different solutions when you’re looking to build something. What are the real differences between the different kinds of cranes? We’ve already touched briefly on the mobile crane idea, with a large vehicle and a crane arm affixed on top. The problem with this, of course, is that having a base that’s not affixed the ground makes it difficult to lift things either very high without the crane actually tipping over. You can often fix this problem by simply getting a heavier base. Crawler cranes, for example, have very low centers of gravity and wide, extremely stable tracks. They can move enormous loads of material as well as move around construction sites and are absolutely indispensable in many cases.

On the other hand, the tower cranes used in very large construction jobs have some very definite advantages as well. It’s impossible, for instance, to build a mobile crane with the same height capabilities of a tower crane, simply because of the way gravity works. A tower crane works because it has a counterweight system that plants the main line of force directly over the main shaft of the crane. Physics and advanced engineering make for an extremely lightweight and stable design that doesn’t actually require that much material in the construction of the crane itself. Because of the way it is designed, a tower crane can be ideal for lifting things hundreds of feet above the ground. As we stated earlier, tower cranes can also be affixed on top of structures in the process of construction. This, of course, is another disadvantage to relying on mobile cranes. Mobile cranes are confined to the ground, and can therefore only lift things as high as the crane arm. This limitation is removed with a structurally supported tower crane.

For very large projects, both mobile cranes and tower cranes may be needed. The largest tower cranes sometimes can’t be built by simply using the normal method of jacking the tower into position. In cases like that, another crane will be used to assemble the tower crane. Why not just use that crane? Simple. Some mobile cranes, especially larger telescoping models, have a very long reach but lack the kind of lifting strength needed for heavy industrial purposes. In cases like that they can be used to lift the relatively lightweight crane elements into place before the real heavy lifting aspect of the construction process can begin.

Once the tower crane is constructed, the crane industry starts to show it’s full capabilities. The tower crane is generally equipped with a block of concrete or similar counterweight material on the “short end” of the crane, while the main boom swings out over the construction site, with plenty of reach and heft to move the heaviest i-beams and construction materials anywhere they’re needed. The control cab is located on top of the crane, so it can be used by an operator at eye level with the top of the crane. At this height, of course, a crane operator has to be very skilled at what he or she does – there’s a lot to risk when you’re swinging two tons of steel hundreds of feet above the ground.

If you’re going to be using a crane on your construction site, you’re going to need people to operate it. For most cranes, that means you – or someone working for you – is going to need a crane operator’s license, or the NCCCO license (National Commission for the Certification Of Crane Operators). Fortunately, there are plenty of places where that certificate can be obtained. The first step, obviously, is to receive the education itself. You can find places willing to train prospective crane operators the same way you can find cranes – by searching online. If you give an employee a crane operator’s license, you’ll be giving them a great new resume asset as well as allowing them to operate your crane for you.

In the end though, all of this really boils down to the same thing. If you’re going to get the best deal in anything – whether that’s renting cranes or buying real estate – the best way to ensure success is a proper education in the field. Knowing the market and the crane industry can make sure that you get the best prices for your time and effort. It can also ensure that you get the right crane for the job – what could be worse than shelling out the money to rent or buy a crane and then find that it won’t work for your project? Researching the crane industry before hand can prevent those kind of problems.