Designers Are Building More Machines That Cost Less to Move from Site to Site

摘要

Aspeciality contractor in Memphis, Tenn., likes to approach rigging jobs the same way auto makers build compact cars. But instead of using computer simulation and modular construction to crank out 1,000 Toyotas, Barnhart Crane & Rigging Co. does it for 1,000-ton picks. In 1997, the mechanical contractor and equipment rental firm originally developed what it calls a "modular lift tower" to replace mobile cranes for pow-erplant construction and retrofit projects. The firm has recently found more uses at petroleum refineries, to install 300 to 1,000-ton hydrotreating vessels that extract sulfur and other contaminants from gasoline and diesel fuel.