A double hook extension spring in stainless steel, made to drawing for wet, washdown and outdoor positions. Stainless removes the coating as a failure point, which is the right answer where a plated spring would simply be delaying corrosion rather than preventing it.
Corrosion resistance is a property of the wire, so a scratch during assembly does not create a rust site.
Where equipment is cleaned regularly with water and detergent, plated carbon steel springs have a short life.
Free length, coil count and hook style are made to your drawing rather than selected from stock.
Keep stainless springs away from carbon steel swarf and tooling during assembly. Embedded carbon steel particles are the usual cause of surface rust spots on otherwise sound stainless parts.
Plated springs rusting from a single handling scratch in a wet environment
Corrosion products contaminating a process that has to stay clean
Dimensional and load figures are set per order against your drawing or sample, so they are marked TBC rather than filled with catalogue numbers.
| Product Type | Tension Springs |
|---|---|
| Raw Material Options | Stainless steel, Spring steel, Carbon steel, 65Mn, Music wire |
| Wire Diameter Range | 0.1-8 mm |
| Surface Treatment Options | Zinc plating, Nickel plating, Silver plating, Gold plating, Tin plating, Galvanizing in various colours, Dacromet, Black oxide, Phosphating |
| Standard | ISO, non-standard and OEM drawings |
| Processing Route | Material sourcing → Coiling and forming → Heat treatment → Surface treatment → Quality inspection → Packing → Shipping |
| Inspection Equipment | Grinding and shot peening machinery; Precision tensile strength testers; Magnetic powder flaw detectors |
| Packing | Plastic bags, cartons or pallets, or packing to your own specification |
| Payment Terms | L/C, T/T, D/A, D/P, Western Union, 30% deposit before production, 70% balance before shipment |
| Lead Time | 7-15 days after the order is confirmed |
| Minimum Order Quantity | Quoted per part — tell us your requirement (TBC) |
| Dimensions and Load Rating | Made to your drawing or sample (TBC per part) |
Every batch follows the same seven step route, with tensile testing and magnetic powder flaw detection carried out before packing.
Available in Stainless steel, Spring steel, Carbon steel, 65Mn, Music wire, in wire from 0.1-8 mm, with any of our nine surface finishing routes. Geometry, end treatment and finish are all specified per order.
ISO 9001, SGS certificate and RoHS report (stated on the legacy site, certificates pending re-confirmation). Certificate copies are sent on request once re-confirmed.
Against a galvanised carbon steel spring, stainless costs more and lasts indefinitely in wet service. Where the environment is dry, the cost is not justified.
304 is the general purpose choice. Tell us the chemicals and temperatures involved and we will confirm whether another grade is more appropriate.
At identical geometry the force differs, so the design is adjusted. Tell us the force you need rather than copying carbon steel dimensions.
Austenitic grades are weakly magnetic in the drawn and coiled condition. If a non-magnetic requirement is strict, say so at enquiry.
Send your drawing, dimensions or a sample. We will confirm the specification and come back with a price and a lead time.
