There are 2 main types of cranes that are used in construction; mobile cranes and tower cranes. A mobile crane is a self-propelled crane that is mounted on a truck and can be driven to the worksite without the need for an additional transportation vehicle. While tower cranes have to be transported by a separate truck and assembled on the job site. They are generally used for constructing high rise buildings as they are much taller than mobile cranes. 

Types Of Mobile Cranes

While tower cranes need to be transported by truck then constructed on-site, mobile cranes can easily be transported on or off-road (depending on the crane type). This makes them the convenient choice for projects that have various locations. Mobile cranes are faster to transport, set up, more compact and can be used for a wide variety of applications including removing industrial waste and heavy-duty lifting. There are many different types of mobile cranes including spider cranes, crawler cranes, Franna cranes, city cranes and all-terrain cranes.

City Cranes

City cranes are specially designed for use in urban environments, where access to sites can be limited. They are compact and their adjustable turning circle and telescopic boom allow them to navigate through tight spaces on construction sites. City cranes are mainly used to perform lifts on both residential and commercial construction sites within urban areas. At St George Cranes, we offer city cranes that can lift a maximum of 10 tonnes and 25 tonnes. The maximum load is dependent on the lifting angle, the extension of the boom and jib.

Franna Cranes

Franna cranes (also referred taxi cranes) are known for their ability to be set up in tight spaces and travel far distances. In terms of design, a Franna crane is a cross between a crane and a truck. They are commonly used to transport heavy loads to workshops, mines, factories and job sites via public roads. The main difference between a Franna crane and other types of mobile cranes is that it can only be used to pick and carry items within a small radius because it has no stabilising legs. At St George Cranes, we offer Franna cranes with a maximum lifting capacity of 15 tonnes and 20 tonnes depending on the radius.

All-Terrain Cranes

An all-terrain crane is a cross between a rough terrain crane (designed to drive on uneven construction sites) and a Franna crane (designed to lift and transport loads on roads). As the name suggests, all-terrain cranes are suitable for use on uneven surfaces and roads. All-terrain cranes are a popular choice as they can be driven on roads and constructions sites. They are also known for their versatility, superior lifting capacity, minimal set-up and high road speeds. St George Cranes offers all-terrain cranes that have a maximum lifting capacity of 55 tonnes.

How Heavy Can A Crane Lift?

The amount of weight a mobile can lift will vary depending on the type of crane. Certain mini cranes can only lift a maximum capacity of 2 tonnes while larger cranes such as heavy-duty crawlers can lift up to 3,000 tonnes. At St George Cranes, we offer cranes that have a lifting capacity from 3 tonnes (mini crawler cranes) up to 55 tonnes (all-terrain cranes). We also offer city and Franna cranes that have a lifting capacity of 10 to 20 tonnes.

What Affects A Mobile Crane’s Lifting Capacity?

The lifting capacity of a crane gives an indication of the heaviest weight that a crane can lift safely in optimal conditions. The crane’s capacity can be affected by different variables including the hanging weight of the load, lifting angle and weather conditions.

Hanging Weight

Identifying the weight of the object being lifted is simple, however, it’s important to note that the hanging weight of the same object is different. The hanging weight of the load is calculated by taking into account the speed at which the crane will lift and move the load.

Lifting Angle

The maximum weight a crane can lift will also depend on how far the boom is extended and at what angle is the crane lifting/moving the load. All mobile cranes come with a lifting capacity char, which indicates the maximum weight a crane can lift based on the length and angle of the boom. The closer the load is positioned to the base of the crane, the more weight it can lift safely and vice versa.

Weather

The main weather element to consider when calculating the maximum lifting capacity of a crane is the wind speed. As heavy winds can cause the load to swing, which drastically increases the amount of force being exerted on the crane. During strong winds, mobile crane regulations dictate that it is not safe to operate a crane at all. Heavy rain may also impact the functionality of the crane.

It is important to understand the load’s weight and the situation that the lifting will take place (angle/extension of the boom, hanging weight and wind level). Cranes can have a maximum lifting capacity from 2 tonnes to 3,000 tonnes depending on their size and design. If you’re considering hiring a mobile crane in Sydney for your job site, contact St George Cranes today.