Abstract: A method for altering or retrofitting an excavating crane such as a trench hoe, back hoe, etc. into a lifting crane having a geometry suitable for scrap handling is disclosed. The conversion method is performed by cutting appropriate notches into the side plates or side walls of the main boom of a conventional crane in an area adjacent the point of connection between the main hydraulic piston and the main boom; bending the boom to form a new geometry on the main boom; forming a suitably configured insert and attaching said insert in the opening formed by the bending of the boom. In this fashion, the geometry of the main boom may be altered without the necessity for altering either the pivot point, the stroke of the pistons or any other portion of the overall crane assembly in order to change the lifting arc and create greater lifting capability.

Abstract: Method and apparatus for altering or retrofitting an excavating crane such as a trench hoe, back hoe, etc., into a lifting crane suitable for scrap handling are disclosed. The conversion is accomplished by cutting V-shaped notches into the side plates of a conventional boom at a point adjacent and outboard of the point of connection between the main hydraulic piston and the main boom; bending the boom so that the edge surfaces formed by the sides of the V-shaped notches are brought into abutment and welding the same together. In this fashion the geometry of the main boom is altered without any necessity for altering either the pivot point, the stroke of the pistons, or any other portion of the overall crane in order to change the lifting arc and permit a greater lifting capability. By this modification, the crane becomes suitable for scrap handling wherein the problem is mainly lifting substantial weights, as contrasted to excavating operations where the reach of the boom arm is of primary importance.