Abstract: A method for erecting absorber towers using trestle means (26) with jack means (32) to assemble a course and then lift it while constructing the next course below it. The first course is lowered on the just assembled course and welded thereto. These steps are repeated to form the outer wall (34) of the absorber tower (10). A clearance (48) is provided between the elevated course and the course to be assembled for installing the internal components of the tower. Advantageously, the method of the present invention allows for the construction of an absorber tower on site in retrofit applications where space may be restricted and access limited.

Abstract: A robot drive for cutting fins having pipes extending on opposite sides therefrom, with the pipes laying in parallel spaced apart rows, comprises a carriage which can move in the longitudinal direction between rows of the pipes. A pair of driven guide rollers is mounted to the carriage for rolling against the pipe of one of the rows. The carriage also carries four spring loaded pressure wheels which bear against the fins of the pipe in an adjacent row so as to press the carriage and guide rollers against the pipe on which the guide rollers roll. A pair of cutting torches or mechanical cutters are connected to the carriage on opposite sides of the guide rollers so that they can cut the fins of the pipes on which the guide rollers roll.