By Chris Petts, Managing Director – Lee Spring UK
Lee Spring is proud of their close to 100 year tradition and are proud to reflect on the considerable growth in availability of springs and development in spring technology during that period.
Standard stock springs are our daily fare. With over 25,000 products catalogued and stocked we see many new products and spring technologies have emerged, perhaps most significantly:
- Redux™ Wave Springs
- LeeP™ Plastic Composite Springs
- Lite Pressure™ Compression Springs
- Bantam™ Mini-Compression Springs
The Redux™ Wave Spring series are designed to replace conventional round wire Compression Springs in applications requiring a tight load deflection specification in a space critical environment – as assemblies get smaller we have seen more requirements for similar capacities in a smaller envelope.
Typically, Redux™ Wave Springs occupy a very small area relative to the amount of work they can perform. In fact, they can reduce the size and weight of the assembly by as much as 50%. They are manufactured from a single filament of Type 17-7 Stainless Steel flat wire formed in continuous precise coils with uniform diameters and waves offered in free lengths from 1.5 mm (0.060”) to 50.8 mm (2.000”) to meet load requirements from 6N (1.3 lbs) to 400N (90 lbs).
More recently, we have seen demands for non-metallic springs to suit high tech’ applications. The LeeP Plastic Composite range is Lee Spring’s response to these increased requests for spring technology with the special attributes of high performing engineered thermoplastics. After years of extensive engineering design and materials research, Lee Spring’s technical team developed this unique compression spring range with composite plastics technology.
These patented designs maximize spring rates and cycle life, while minimizing solid height, offering high strength to weight ratios that optimize performance while reducing mass. They have excellent stability of physical and mechanical properties at elevated temperatures up to 340°F with high corrosion resistance and are generally compatible with common industrial chemicals including strong acids, weak bases, aromatics, and ketones. Their non-magnetic material does not interfere with imaging and other Ferro-sensitive technologies, while the dielectric insulating material is suitable for non-conductive applications. These inert plastic composite springs do not contaminate associated equipment and have low flammability and toxicity ensuring environmental safety. The plastic composite material is recyclable and compliant with most Global regulations including RoHS and REACH.
Another demand which came about from developing technologies was for a low pressure spring technology series for smaller, lighter operation of low mass devices. This requirement caused us to develop the Lite Pressure™ Series which was designed so that, for a given length and diameter, we could offer a series of springs that had lower spring rates or workable load ratings than those currently offered by the existing standard compression springs. This series was recently expanded to include new larger sizes to work in hole diameters up to 3” wide.
As advanced new technologies developed with ever lighter smaller devices, an important gap was identified, leading to the Bantam™ Mini Compression Spring range which is a unique line of miniature springs. These Stock products are offered in wire sizes .0040”, .0045”, .0050” and .0055”. The Inch sizes include selections to work inside hole diameters 1/32″, 3/64″ and 1/16″ and in a range of free lengths from .050″ up to .625″. Metric sizes include selections to work inside hole diameters 1mm, 1.5mm and 1.8mm in a range of free lengths starting at 1mm up to 12mm. In order to meet and maximize the performance needs of a potentially diverse range of applications, Lee Spring selected the advanced material Elgiloy® as the alloy of choice for Stock BANTAM Mini Springs.
Elgiloy® is a Cobalt-Nickel alloy known for its high strength, for example it is 10% stronger than Type 316 Stainless Steel. It exhibits superior resistance in most corrosive environments including acetic acid, ammonium chloride, citric acid, sodium chloride and sodium sulfite. This material performs well in temperatures up to 850° F. Elgiloy® is non-magnetic and therefore ideal for use in delicate and highly sensitive instruments.
Even with over 25,000 stock items it is impossible to stock something suitable for all applications – indeed growth in custom demand for new applications has more than kept pace with ex-stock requirements – leading us to create our Custom Springs Direct service including: Compression, Extension and Torsion springs with wire diameter range: .002” – .625”, and a wide range of stock alloys including: Music Wire, Stainless Steel 302, 17-7 and 316, Phosphor Bronze, Hastelloy ®, Inconel 600, 718 and x750, Beryllium Copper, and of course Elgiloy.
Even in 1995 Lee Spring offered a wide range of Fourslide parts, including flat springs, brackets, clips, flat terminals, in fact pretty much any sort of stamped and formed metal components. These parts are often natural candidates for fourslide manufacture as intricate metal parts, using flat strip material or from drawn or rolled wire.
Fourslide parts are complimented by Wireforms and Stampings, as well as assemblies of these products.
Naturally much has also changed in terms of regulation and compliance – an area where Lee Spring is well placed to offer products to relevant standards including:
- BS EN ISO 9001:2008
- RoHS Compliance
- REACH Compliance
- DFARS Compliance
- MS (material traceability)
- Export Regulations