In this article, we will talk about the main parameters and types of tower cranes. You will also find out what to look for when choosing this equipment and where you can buy a machine at a bargain price. This information will be useful to employees of construction companies, engineers, construction site operators and anyone who wants to learn more about the functionality of cranes and their effective use.
Types of tower cranes: classification
Depending on the type of support, tower cranes are divided into the following types:
- Stationary. This type of equipment is installed on a fixed base, usually a reinforced concrete platform, and can be additionally secured by an anchor system. It is suitable for the construction of tall buildings, as it is capable of lifting very heavy loads, such as large building blocks and elevator cabins, to great heights. Stationary tower cranes are often used for long-term projects.
- Mobile. These machines are mounted on wheeled chassis or tracked supports, which ensures their mobility on the construction site. The machine can be quickly moved between different work points or even to a neighboring site. Mobile cranes are suitable for urgent projects.
- Attached. This type does not have a chassis; the building itself is the support for the machine: the crane is installed on the foundation, and the tower is attached to the wall. This design allows you to increase the lifting height. Overhead cranes are effective when working on cramped and congested construction sites where the installation of a standard crane is impossible or impractical.
- Self-elevating. These cranes are installed inside the facility under construction. The base of the machine rests on the ceiling, and the crane is pulled up with a winch. In this way, it rises simultaneously with the building and can transport cargo to any height. Self-lifting machines are used in the construction of the tallest buildings.
Classification of tower cranes by platform type:
- with a rotating platform – suitable for urgent projects, they are easy to transport and assemble;
- with a fixed tower – suitable for complex construction and have a high load capacity.
The following types of cranes are distinguished by tower design:
- lattice cranes – lightweight, with minimal windage;
- solid-tensile – heavy, effective at low temperatures.
Cranes can be divided according to the way the boom departs:
- beam – with a static, horizontal boom that is adjusted by moving the trolley with a trailing device. Although such equipment has a more complex design and more weight, the size of the working area increases;
- lifting – the length of the boom is adjusted horizontally by turning it relative to the hinge. This is a highly maneuverable technique capable of lifting heavy loads to great heights;
- articulated – the reach of the boom is regulated by increasing the angle of lift and by a horizontal guide. This technique is more versatile, but more expensive.
Tower crane: technical characteristics
Tower cranes have a generalized design, including a support base and a tower (mast) that supports a lifting boom. The boom is equipped with a hook or other devices for lifting loads. The design of the equipment also includes a driver’s cab and pivot mechanism, a chassis, a turntable, a ladder, a platform and a device for transporting along curves.
General characteristics:
- outreach of the working body – from 25 to 80 m
- lifting capacity – from 5 to 75 tons;
- lifting height – up to 220 m;
- load lifting speed per minute – from 2 to 200 m;
- number of revolutions of the crane structure per minute – from 0.2 to 1;
- travel speed per minute – from 10 to 30 meters.
Electrically driven lifting machines are equipped with safety devices: various limiters, door locks, emergency switches, protective panels, anemometers and signaling devices.
If you’re looking for construction equipment, visit Machineryline. This is an online platform for the sale of special equipment, spare parts and industrial equipment. It offers a wide range of new and used models that can be purchased on credit or lease. You can also find repair services on the site.
Lifting capacity of tower cranes
The lifting capacity at the maximum outreach can range from 5 to 75 tons, depending on the platform design. Cranes with a rotary platform are usually capable of lifting up to 25 tons. Cranes with a fixed tower can lift up to 75 tons. Such machines are mainly used in the construction of dams, nuclear power plants and spaceports.
The indicator may vary depending on the height to which the load is to be lifted. The higher the load is lifted, the lower its maximum weight.
If the weight of the load exceeds the set parameters, the load limiter is activated and the boom or lifting mechanism automatically shuts down. This function protects against the breakage of cables and ropes, damage to the hook, overturning of the crane structure, and the formation of cracks and chips in metal structures.
Maximum height of a tower crane
Depending on the model, this figure can range from 20 to 220 meters. The height of the crane tower can also be adjusted according to the needs of a particular project.
How a tower crane works: principle of operation and features
The principle of operation of a tower crane is to lift and lower a load using a load gripping device, usually a hook, and a lifting boom. The boom can be raised and lowered, as well as rotated, to accomplish the desired task. Counterweights are installed on the other side of the boom to ensure the stability of the crane. On equipment with a rotating tower, special spacers are used instead, with the help of which the branches of the boom ropes are diverted from the tower. The tower crane allows you to effectively manage and deliver metal structures, parts of the structure, and building materials to the desired point on the site. The machine itself can also be rotated using a swivel mechanism.
Construction cranes of various types and designs can be found on the Machineryline website. You can also place your own ad for the sale of equipment on the site.
How to choose a crane for construction
The speed, quality, safety, and profitability of construction will depend on which model you choose. Therefore, it is better to draw up a work project in advance, taking into account the planned costs of maintenance and operation of the equipment. When choosing a tower crane, it is important to take into account the key parameters that must meet a specific construction task:
- Mobility. Stationary models perform work in one place. Mobile ones can be moved a limited distance, for example, by rails. Self-propelled equipment has the highest maneuverability. Cranes on a car chassis can move freely around the construction site and beyond.
- Maximum load capacity. For monolithic construction, machines with a lifting capacity of 6-8 tons are suitable. If heavy metal trusses are used, special equipment with a lifting capacity of up to 10-12 tons is required.
- Lifting height. At maximum lifting, the hook should remain 6-10 m below the calculated height of the structure, otherwise it will be necessary to use an additional fixation of the crane to the building structure. Such an attachment requires large additional investments. It is more profitable and convenient to take the equipment of the desired height right away.
- The length of the boom. This characteristic of a tower crane is related to the dimensions of the building. The boom must be able to reach any point of its perimeter. If one crane is not enough, use two or more cranes. The main thing is to install them in such a way as to prevent collisions. If the cranes work in the same area, they need to be separated in height and in plan.
- Installation. For the construction of low-rise buildings or the implementation of a point production project using metal structures, it is better to take a crane that can be installed quickly.
- After-sales service. Much of this depends on the manufacturer’s brand. Popular companies usually have authorized maintenance services in different regions. The availability of such centers simplifies the process of replacing parts and repairing equipment, especially during operation.
In addition, the technical characteristics of lifting equipment must meet the conditions of its use. It is necessary to take into account the territorial limitations of the facility, the presence of obstacles in the work area, the remoteness of the warehouse, change houses and utility rooms. Much depends on the condition and quality of access roads to the work area, restrictions imposed by regulatory authorities, and the quality of the soil at the construction site. For example, for work on swampy, loose or sandy ground, tracked equipment is better suited.
In addition, you can consider how comfortable the driver’s workstation is, the ease of operation and design of the joysticks, and the availability of programs that facilitate maintenance and troubleshooting.
Find the best deals on for sale tower cranes on Machineryline!
More than 600 ads of tower cranes for sale from sellers from all over the world and Europe on Machineryline.
To summarize: how to choose the right tower crane? First, you need to draw up a work plan, then, based on the tasks and operating conditions, select a model with the appropriate characteristics.
