The purpose of hydraulic cranes is to stay stable whilst lifting heavy weights. Although cranes have been used throughout the history of construction engineering, hydraulic cranes use a more technical design. If you’re considering making a purchase any time soon, there are several factors that you should keep in mind. The hydraulic crane depends on three separate parts when lifting incredibly heavy loads: the hydraulic cylinder, the pulley and the lever. The latter is a horizontal beam that takes on the task of the fulcrum. When a heavy object is loaded, an amount of force is applied at the other end, and in the other direction. Known also as the jib, the pulley is a strut tilted to support a pulley block. The fixed block is wrapped with several layers of cable that is then pulled by machine or by hand. This can then create a force that is equal to the weight of the load. The hydraulic cylinder is then used to lift the load. Hydraulic cranes are available in a number of different types, and understanding what the differences are can help when you make your choice. · Tower crane . This modern piece of technology can either be fixed on a structure such as a building or fixed on the ground. They are typically favoured for their height in addition to their lifting capacity. They are essential when it comes to the construction of tall buildings. · Railway crane. Typically used to support the maintenance of railway tracks, its wheels are flanged in order to be able to use the tracks to travel. Some hydraulic railway cranes are custom designed, with others being basic enough to be mounted onto a car. · Self-erecting crane. Designed to make it easy to assemble, this type of crane will lift itself up from the ground in order for the next segment of crane to be inserted. Self-sufficient so no outside help is required. · Telescopic crane. A number of tubes are fitted inside the other to provide a boom that will extend to the required length. These are suited to short terms jobs such as construction or even rescue. · Manual crane. When there is no accessible power, manpower is required. Rarely used for construction, but sometimes brought in for special jobs, these do not run off electricity and are very cost effective. Hydraulic cranes are just another use of the ingenious hydraulic system that our Greek forefathers discovered, but one that has changed the face of this planet, our skylines and how we live.