Reinforcement for a moulded filtering screen support frame

Abstract

A method is described for making a reinforcing wire frame for embedding in a moulded polymer support frame over which woven wire cloth is to be stretched and secured to form a sifting screen. The method involves locating lengths of cut wire substantially equally spaced apart in a jig to form a first array. A second array of lengths of cut wire is located over the first array with the lengths of wire in the second array being substantially at right angles to those of the first array. The lengths of wire in the first and second arrays are resistance welded at points of mutual intersection so as to form a first substantially rectilinear matrix. Lengths of cut wire are located in a jig to form a third array, in which the lengths are also substantially equally spaced apart, and a fourth array of lengths of cut wire is arranged over the third array with the lengths of the fourth array substantially at right angles to the lengths of wire of the third array, and the wires of the third and fourth arrays are also resistance welded at points of mutual intersection to form a second substantially rectilinear matrix.