Vicinay Cadenas S.A is a world leader in the manufacture of mooring chains for the offshore industry. Welding is a key part of chain manufacturing. This study seeks to determine how the manufacturing parameters of welding machines influence the appearance of inhomogeneities. The idea is to optimise current manufacturing processes and acquire knowledge that will enable the firm to develop new products with diameters in excess of those produced to date. To that end, multivariate analysis techniques are used to study manufacturing data on various chains and an algorithm is designed to select the spreads of the adjustable variables that contain the lowest (highest) percentage of links with inhomogeneities. The application of this algorithm to a number of chains with different diameters manufactured on the same machine provides an estimate of the table of settings that should be used to make chains with dimensions larger than those currently made.