For parallel keys in A2 Stainless Steel, the controlling selection factors are corrosion exposure, strength requirement and service temperature. The grade data for A2 Stainless Steel (A2-70 (304)) is summarized below together with every size supplied.
Why Choose A2 Stainless Steel for Parallel Keys
The most common stainless grade for indoor and general outdoor fasteners. For parallel keys, this matters when good general corrosion resistance is the primary requirement.
Mechanical & Physical Properties
| Grade designation | A2-70 (304) |
|---|---|
| Magnetic response | Largely non-magnetic |
| Service temperature | approx. -200 °C to +400 °C |
| Corrosion characteristic | Good general corrosion resistance |
Corrosion Behavior in Service
A2 (304) gives excellent atmospheric and most-water corrosion resistance and is the most common stainless for Parallel Keys in indoor and general outdoor service. In chloride-bearing environments (marine air, road salt, swimming pools) consider stepping up to A4 (316).
Galvanic & Galling Considerations
Two important notes for stainless parallel keys: (1) stainless can gall on stainless threads under load — use a thread lubricant or anti-galling compound, especially for M6 and below; (2) when joined to aluminum or galvanized steel, stainless can drive galvanic corrosion of the less-noble metal in wet service — isolate with a coating or sleeve where appropriate.
Sizes of Parallel Keys Available in A2 Stainless Steel
| Shaft diameter range (mm) | Key width b (mm) | Key height h (mm) | Key length range (mm) | Shaft groove depth t1 (mm) | Hub groove depth t2 (mm) | Reference standard | Notes |
|---|---|---|---|---|---|---|---|
| 6~8 | 2 | 2 | 6~20 | 1.2 | 1.0 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 8~10 | 3 | 3 | 6~36 | 1.8 | 1.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 10~12 | 4 | 4 | 8~45 | 2.5 | 1.8 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 12~17 | 5 | 5 | 10~56 | 3.0 | 2.3 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 17~22 | 6 | 6 | 14~70 | 3.5 | 2.8 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 22~30 | 8 | 7 | 18~90 | 4.0 | 3.3 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 30~38 | 10 | 8 | 22~110 | 5.0 | 3.3 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 38~44 | 12 | 8 | 28~140 | 5.0 | 3.3 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 44~50 | 14 | 9 | 36~160 | 5.5 | 3.8 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 50~58 | 16 | 10 | 45~180 | 6.0 | 4.3 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 58~65 | 18 | 11 | 50~200 | 7.0 | 4.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 65~75 | 20 | 12 | 56~220 | 7.5 | 4.9 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 75~85 | 22 | 14 | 63~250 | 9.0 | 5.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 85~95 | 25 | 14 | 70~280 | 9.0 | 5.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 95~110 | 28 | 16 | 80~320 | 10.0 | 6.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 110~130 | 32 | 18 | 90~360 | 11.0 | 7.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 130~150 | 36 | 20 | 100~400 | 12.0 | 8.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 150~170 | 40 | 22 | 100~400 | 13.0 | 9.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 170~200 | 45 | 25 | 110~450 | 15.0 | 10.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 200~230 | 50 | 28 | 125~500 | 17.0 | 11.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 230~260 | 56 | 32 | 140~500 | 20.0 | 12.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 260~290 | 63 | 32 | 160~500 | 20.0 | 12.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 290~330 | 70 | 36 | 180~500 | 22.0 | 14.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 330~380 | 80 | 40 | 200~500 | 25.0 | 15.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 380~440 | 90 | 45 | 220~500 | 28.0 | 17.4 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |
| 440~500 | 100 | 50 | 250~500 | 31.0 | 19.5 | DIN 6885 type A / ISO 773 | Type A round ends; B square ends; C one round one square |