Medical springs deliver lifeline performance

While springs are widely used in the medical sector, from insulin delivery through to surgical tools and equipment, the latest lightweight plastic composite and miniature springs are expected to open up new applications.

For fluid and motion control in medical and surgical equipment compression springs are the most common type used and Lee Spring has over 3500 Type 316 stainless steel stock compression springs in its portfolio of 16000 plus different products. Its stainless steel compression springs, passivated and ultrasonically cleaned instrument springs and Lite™ Pressure and standard compression springs are being used by leading international medical companies. Making their mark in the medical sector are two innovations that break new ground in spring technology - LeeP™ plastic composite compression springs and Bantam™ Mini compression springs. Plastic composite springs have many performance differentials with metal springs including high strength to weight ratios, mechanical and thermal stability at temperatures up to 170oC (340oF) and excellent corrosion resistance. Additionally they are non-magnetic, offer dielectric insulation, low flammability and are recyclable. Manufactured in different formulations of Ultem PEI resin, the springs are available in six colour coded strengths. Standard sizes and custom design options are available to meet performance requirements. Developed to meet the challenge of miniaturisation Bantam™ Mini compression springs are designed to combine strength with corrosion resistance. Manufactured in Elgiloy®, a cobalt-chromium-nickel alloy that can withstand temperatures up to 454°C (850°F), the smallest size spring features a wire diameter size of 0.102mm (0 .004ins) - just slightly thicker than a human hair. Applications for these spring types are expected in medical apparatus such as imaging and X-ray equipment as well as in pharmaceutical delivery products. Alongside its stock range Lee Spring also designs and produces a huge variety of custom springs, including wire forms, washers, stampings and assemblies, many for the medical market. Material options include music wire and a range of alloys including stainless steel 316 and 17-7, Inconel 600, phosphor bronze, beryllium copper and Hastelloy. www.leespring.co.uk