Cranes Enabled Faster, Safer Construction of Tall Buildings
 Wolffkran GMBH |
 Wolffkran GMBH |
 Wolffkran GMBH German maker Wolff made the first tower crane in 1910. |
Not all tower cranes are created equally: Some resist fatigue, lift and cost more than others. But all are built under similar engineering principles linked by a common history.
While most mobile cranes evolved from steam shovels, all cranes harken back to the earliest lifting devices, which were simple derricks and gantries fitted with gears, ropes and other tackle used by the Ancient Egyptians, Greeks and Romans to move heavy stones needed to build structures. It wasn’t until the first tall-building boom at the turn of the last century that tower cranes as we know them began to arrive.
Tower-crane technology evolved from scaffold-mounted derricks built by firms like U.K.-based Morris & Bastert Ltd. in the late 1800s. In 1854, Friedrich August Wolff, a tin producer, opened an iron foundry in Heilbronn, Germany, and his son, Julius Wolff, moved into cranes. In 1897, Wolff received a patent for a safety brake and in 1908 hired Gottlob Gobel, who in 1910 built the first modern tower crane, a small, rail-mounted unit. Wolff displayed a larger, refined model with a top-slewing and luffing jib in 1913 at the Leipzig Trade Fair, according to The History of Cranes (KHL 1997). Records show the crane went up in four days—fast for the era. Wolff was a hit, but a foundry fire in 1924 and the Nazi movement later stunted its growth. Wolffkran Gmbh exists today in the same city, but it does not sell in the U.S.
 Liebherr Group Liebherr pioneered postwar cranes. |
After the war, master-builder Hans Liebherr developed a low-priced, quick-erecting crane in 1949 in Kirchdorf, Germany. It had a 16-meter jib and 1,000-kg capacity. Tower cranes rapidly increased in size, and Liebherr in 1956 went on to design the first self-climbing tower crane, the 25H. Most brands now offer climbing cranes.
Self-climbers soon became an important tool for tall structures. Though tower cranes “grew up” in steel erection, concrete firms later enjoyed the speed and cleanliness, cutting the hazardous and messy skip hoists, landing platforms and mix buggies of the day. Crane technology has improved, but operating risks also have become more complex.
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