Compression Spring Wire Dia.=1.4mm OD=17mm~25mm A2 Stainless Steel Y Type Spring

Measure the inner diameter of your housing bore or the outer diameter of your guide rod. For a bore-mounted spring, the OD should be 0.5–1.5 mm smaller than the bore ID to allow free movement. For a rod-guided spring, the spring ID (OD minus 2× wire diameter) should be 0.5–1 mm larger than the rod OD. With a 1.4 mm wire, the ID is approximately OD − 2.8 mm.

Select a free length that is longer than your required compressed length by at least the travel distance you need. For example, if you need 15 mm of travel and a compressed length of 20 mm, choose a free length of at least 35 mm. Always leave a small solid-height margin to avoid coil bind.

Yes. A2 (304) stainless steel offers good resistance to atmospheric corrosion, moisture, and mild chemical exposure. It is widely used in outdoor fixtures, marine-adjacent equipment, and food-adjacent machinery where rust is a concern. For highly aggressive salt-spray or chemical environments, A4 (316) stainless would be a stronger choice.

"Y-type" refers to a closed and ground end configuration. The end coils are wound tightly (closed) and then ground flat, creating a stable, perpendicular seating surface. This reduces lateral buckling, improves load distribution, and allows the spring to sit squarely in a pocket or against a flat surface without tilting.

A2 stainless steel compression springs are typically rated for continuous use up to approximately 200°C (392°F). For intermittent exposure or applications approaching this limit, verify that the spring rate loss at elevated temperature is acceptable for your design. For sustained high-temperature use above 250°C, consider alloy steel or Inconel springs instead.

The springs themselves are identical in specification — same wire diameter, OD, free length, material, and finish. The 20-piece pack simply provides a larger quantity at a lower per-unit cost, making it suitable for production runs, workshop stock, or projects requiring multiple springs of the same size.

The inner diameter is calculated as OD minus twice the wire diameter. With a 1.4 mm wire: ID = OD − 2.8 mm. For example, the OD 17 mm spring has an ID of approximately 14.2 mm; the OD 25 mm spring has an ID of approximately 22.2 mm. Use this to confirm guide rod clearance.