Method to make an arm for the distribution of concrete, and arm thus made

Abstract

A method to make an arm for the distribution of concrete, or other material similar to concrete, used on heavy work vehicles, wherein the arm comprises a plurality of segments selectively folding and extendible one with respect to the other. Each segment comprises a main girder and auxiliary elements for connection to adjacent segments or for attachment of movement and/or supporting devices for the pipe that carries the concrete. The method comprises a first step in which each main girder is formed, with a predefined length, by depositing a plurality of layers of pre-impregnated composite material in a female type mold. The method comprises a second step in which the composite material, deposited in layers in the mold in a variable number of layers, is subjected to polymerization. The method comprises a third step in which each main girder is removed from the mold and a fourth step in which the auxiliary elements are associated with each girder so as to form a relative segment. The method comprises a fifth step in which the extendible arm is assembled, connecting the various segments at the respective ends. The cross section of each of the main girders of the segments is substantially constant over the whole length thereof. The female mold consists of one or more elementary molds of equal section, connected in sequence with each other according to the overall length of the main girder to be made.