Although Lee Spring carries over 23,000 catalogued items, it is just as common to find that a variant or complete custom item is required to suit a new design or new assembly process. A special spring design may add quality to product operation or its longevity, often with significant savings in component cost and/or assembly time.
Lee Spring technical and cultural capability, derived from experience since 1918 working alongside customers, enables it to develop project specifications to international standards such as RoHS, REACH and DFARS. The company can hand-hold customers through the specification prototyping, development/trials process to final sign-off and mainline production. This includes full CAD modelling on to prototyping and supply chain management for commercial, industrial, aerospace and military sectors. Custom springs may be stocked in depth to meet customers’ demand schedule, so enabling efficient and timely delivery wherever required worldwide, it states.
"Typical custom variants of standard springs include varying finishes, alternative materials for enhanced performance, polishing or coating, non-standard loadings, non-standard sizes, matching to suit exceptional environments, demands for extreme longevity or specific concerns regarding materials matching etc." A common request is to meet tighter tolerances required for specialist housing designs. This custom process encompasses special standards requirements, non-standard finishes – for aesthetic or functional reasons, such as colour matching or colour coding, special shapes, special end forming, retaining clips – wire forms and stampings/other formed metal parts (fourslide parts), trim clips etc.
Specification of custom springs or components can involve production in materials such as beryllium copper, brass, hard drawn carbon steel, oil tempered carbon steel, oil tempered chrome silicon, oil tempered chrome vanadium, Elgiloy, Hastelloy, Inconel, Monel, music wire, phosphor bronze, plastic composites, 300 series stainless steel, 17-7 stainless steel.
A vital part of custom design of course is the selection of secondary operations such as assembly, colour coding, electro-polishing, grinding, heat treating, looping, passivation, powder coating, shot peening, spring setting, plating - eg with nickel or zinc - and use of other special finishes, such as black oxide.
