304 Stainless Steel Compression Spring Wire Dia 4mm, L 20-100mm, OD 20-60mm

Measure the bore or housing ID your spring must fit inside — the spring OD should be 1–2mm smaller than the bore for clearance. For free length, select a spring that is longer than your required compressed length so it still exerts force at full compression. Use the variant selector above to browse available OD and length combinations.

Load capacity depends on OD, free length, and number of active coils — all of which vary by variant. As a general guide, 4mm wire springs in this OD range typically handle medium-duty loads. For precise spring rate and maximum load data for a specific size, contact us to confirm before ordering.

Yes. Grade 304 stainless steel offers solid resistance to atmospheric corrosion, fresh water, and mild chemical exposure. It is widely used in outdoor machinery, marine-adjacent applications, and food-processing equipment. For highly aggressive salt-spray or chloride-rich environments, 316 stainless may be more appropriate.

Yes, provided the guide rod diameter is smaller than the spring's inner diameter (ID = OD minus twice the wire diameter). For example, a 4 × 30mm spring has an ID of approximately 22mm, so a guide rod up to ~20mm diameter would fit with clearance. Always verify dimensions against your specific variant before assembly.

Many mechanical assemblies use springs in matched pairs — bilateral actuators, parallel return mechanisms, and balanced clamping fixtures all benefit from identical spring sets. Selling in pairs ensures you receive a matched set and simplifies stocking for maintenance applications.

304 stainless steel retains adequate mechanical properties up to approximately 300°C (572°F) for intermittent exposure. For continuous high-temperature service above this range, consider springs made from high-temperature alloys. Contact us to confirm suitability for your specific operating conditions.

Spring rate is determined by wire diameter, OD, and number of active coils. Because this product covers a wide range of sizes, spring rate varies by variant. If you need a specific rate (N/mm or lbf/in), please contact us with your OD and free length selection and we can provide the calculated value.