Complex sentence: Taking seven years to build between 1944 and 1951, the crane was at the time the largest crane in the Southern Hemisphere and was built to lift warship engines, boilers, gun turrets and guns of up to 250 tons.
Split into simpler sentences: Taking seven years to build between 1944 and 1951, the crane was at the time the largest crane in the Southern Hemisphere. Being built to lift warship engines, boilers, gun turrets and guns of up to 250 tons.