A4 Stainless Steel Linch Pins (Spring-Leg Retaining Pins) are supplied to Trade series (linch pin). The grade provides superior, including marine and chloride environments and is largely non-magnetic; the practical service range is approx. -200 °C to +400 °C, subject to the property class and the joint. Property data, grade comparison and the full size table follow.
Why Choose A4 Stainless Steel for Linch Pins (Spring-Leg Retaining Pins)
Specified for marine, coastal and chemical applications. For linch pins (spring-leg retaining pins), this matters when superior, including marine and chloride environments is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 3506 group A4 (316 / 1.4401), commonly supplied A4-80 |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C, subject to the property class and the joint |
| Corrosion characteristic | Superior, including marine and chloride environments |
Corrosion Behavior in Service
A4 (316) adds 2–3% molybdenum to the A2 (304) composition, which dramatically improves resistance to chloride-pitting corrosion. For Linch Pins (Spring-Leg Retaining Pins) in marine, coastal, swimming-pool or food-processing environments, A4 is the default selection.
Galvanic & Galling Considerations
For stainless linch pins (spring-leg retaining pins) the compatibility question is galvanic rather than galling: joined to aluminum or galvanized steel in wet service, stainless drives corrosion of the less-noble metal. Isolate with a coating, sleeve or non-conductive washer where the joint sees moisture. Note also that stainless is softer than hardened carbon steel, so where the part carries a wear or shear duty, check the load against the grade before substituting.
Using Stainless Fasteners in Aluminum
Stainless steel is more noble than aluminum, so with an electrolyte present — rain, condensation, salt spray — the aluminum becomes the anode and corrodes at the joint. Area ratio decides how bad it gets: a small stainless fastener in a large aluminum section is normally acceptable, a large stainless fastener in thin aluminum is not. Where the joint gets wet, isolate the metals with a coated or nylon washer and a sealant, or specify an aluminum or coated fastener instead.
Sizes of Linch Pins (Spring-Leg Retaining Pins) Available in A4 Stainless Steel
| Shank diameter d (mm) | Usable length (mm) | Ring diameter (mm) | Spring leg | Working load (kg) | Material | Finish | Retainer |
|---|---|---|---|---|---|---|---|
| 6 | 32 | 25 | Integral wire | 200 | Spring steel | Zinc plated | Integral |
| 8 | 42 | 30 | Integral wire | 350 | Spring steel | Zinc plated | Integral |
| 10 | 50 | 35 | Integral wire | 550 | Spring steel | Zinc plated | Integral |
| 12 | 60 | 40 | Integral wire | 800 | Spring steel | Zinc plated | Integral |
