Cranes are essential to international trade. Specialized gantry cranes help load and unload ships and are prominent in ports all over the world. Older cranes will pick up one container at a time but newer ones can pick up four.
Tower cranes are basically a modern form of a balance crane. Either fixed to the ground or attached to the sides of a structure, tower cranes offer the best combination of height and lifting capacity, and are perfect for jobs in which height is a factor.
The ancient Greeks are thought to be the first to have invented the modern construction crane. Modern archaeologists believe that early Greek architecture like the Parthenon, the Temple of Zeus, and other iconic buildings were constructed using cranes.
When the time nears to install the crane at your facility, we will work with you to limit its impact while we work, so that your operations are either not interrupted at all, or the interruption is minimal.
In 1873, William Sellers & Co. issued a comprehensive catalog of cranes, lathes, steam hammers, and drills manufactured by the company. The catalog serves as a particularly valuable record today because it features photos instead of drawings.
For structures that require great strength, particularly in cranes designed to lift very heavy objects, a variety of substances known as high-strength low-alloy (HSLA) steels are used. HSLA steels contain relatively low levels of carbon, typically about 0.05%.
Both archival and pictorial sources of the Medieval Times suggest that newly introduced machines like treadwheel cranes did not completely replace more labor-intensive methods like ladders. Rather, old and new machinery continued to coexist on construction sites and harbors.
A crane hook or lifting hook is a critical part of the lifting mechanism, as it is able to grab objects. One of the most important considerations when choosing a hook for your crane is safety: both the materials used and the manufacturing process should ensure a high quality hook.
The American Society of Mechanical Engineers (ASME) is charged with establishing standards and safety codes for crane operations and their operators. We vigorously adhere to the highest established safety standards.
An important factor in the operation of cranes has to do with stability (achieved through the crane’s design). Basically, the crane is going to achieve stability with the sum of all movements around the base of the crane equals zero.
Ensuring equal tension on all three legs of a sling bridle is crucial for safe lifting. For this, all slings must be of the same length, the connection points must be the same distance from each other, and the slings set at an equal distance from each other.
Many world known politicians started their careers as crane operators. Among those who started as crane operators were several politicians from United States in the legislative sector of the government, few British and Australian MP’s, and few well-known English authors.
Did you know that the appropriately named Bigge 125D AFRD is the largest A-Frame crane in the world? It was built in 2011, and can lift over 6,800 metric tons, the most amongst modern cranes of the same type.
The “colossal crane” built in 1860 by William Fairbairn was state-of-the-art. Manual power was “multiplied 632 times by the gearing and blocks. Two men are sufficient to move round the crane with 60 tonnes suspended from the extreme point of the jib.”
When using chokers, there are several different configurations to consider, and the correct one to use depends on the load being lifted. Using an incorrect configuration not only makes lifting and placing more difficult, but it also creates a safety hazard.
In a crane’s design, the horizontal movement can be achieved in one of two ways. Either the entire device is mounted on a rotating pivot (so the load-bearing beam can be swung around) or the load is rolled back and forth on tracks along the boom itself.
The United States government sets specific regulations through the Occupational Safety and Health Administration that limit the weight that a specific crane is allowed to lift. The Crane Manufacturers Association of America sets its own safety standards which exceed those required by the government.
Railroad cranes are generally used in railway line construction, repairing and maintenance. These cranes have flanged wheels at their bottom that can easily move on the railway tracks.
Crawler cranes were once thought to be the universal construction crane, and in many ways, they still are. For example, crawler cranes, because they are self-propelled, are ideally suited for construction sites where they may be needed in multiple places. These cranes also need almost no set-up or staging area.
It sounds counterintuitive, but the invention of cranes encouraged ancient builders to use smaller rather than larger blocks. The smaller size allowed them to build structures with more complex designs and taller, thinner walls.
Ever wonder how the Romans could build incredible buildings like the Colosseum or Pantheon? Today, we’d use cranes, and so did they. But they didn’t have the machines we do, so they used winches or large treadmills to power their cranes.
If you’re interested in the evolution of cranes, visit the reading room at Lehigh University. They have an original copy of The Advancement of the Arts, Manufactures, and Commerce, a 1776 atlas depicting cranes, agricultural equipment, and other innovative machines of the era.
