In one line
Austeritic 304 and 304L: the general-purpose grade for automotive sensor housings, with the balance of drawability, corrosion resistance and availability that makes it the default choice for a first programme.
Published configurations in this grade
47 published configurations use SUS 304, across the denso-heat-shields, motorcycle, nox, o2-b, o2-d, o2-n, other series. Heights run 0.1-48.5 mm, outer diameters 9.10-80.00 mm, recorded wall thicknesses 0.30, 0.40, 0.50, 0.60, 0.80, 1.00 mm.
| Code | Series | Height | OD | ID | Wall | Material |
|---|---|---|---|---|---|---|
| A002-1 | o2-b | 28.5 mm | 12.1，13.8，18.5，21.73 mm | 11.1，12.8，17.5，20.73 mm | 0.5 mm | sus 304 |
| B002-2 | o2-b | 12.4 mm | 14.6 mm | 13.45 mm | 0.5 mm | sus 304 |
| B002-6 | o2-b | 11.5±0.1 mm | 14.6 mm | 13.5±0.05 mm | 0.5 mm | sus 304 |
| B003 | o2-b | 10±0.15 mm | 10 mm | 9±0.1 mm | 0.5 mm | sus 304 |
| B003-2 | o2-b | 10±0.15 mm | 10 mm | 9±0.1 mm | 0.5 mm | sus 304 |
| B006 | o2-b | 13.5 mm | 11.6，15.4 mm | 10.6，14.4 mm | 0.5 mm | sus 304 |
| L041 | nox | 10.1 mm | 12.43 mm | 11.43 mm | 0.5 mm | sus 304 |
| C002-1 | o2-d | 25 mm | 12.35，17.1 mm | 11.35，16.1 mm | 0.5 mm | sus 304 |
| C003 | o2-d | 44 mm | 11.4，14.2，16.8，21.4 mm | 10.5，13.2，15.8，19.1 mm | 0.5 mm | sus 304 |
| C003-0 | o2-d | 44 mm | 11.4，14.2，16.8，21.4 mm | 10.5，13.2，15.8，19.1 mm | 0.5 mm | sus 304 |
| C003-3 | o2-d | 44 mm | 11.4，14.2，16.8，21.4 mm | 10.5，13.2，15.8，19.1 mm | 0.5 mm | sus 304 |
| C004 | o2-d | 25 mm | 11.5，17.1 mm | 10.5，16.1 mm | 0.5 mm | sus 304 |
| D001-2 | o2-d | 48.5 mm | 12.4，15.3，17.7 mm | 11.5，14.3，16.7 mm | 0.5 mm | sus 304 |
| D001-3 | o2-d | 48.5 mm | 12.4，15.3，17.7 mm | 11.5，14.3，16.7 mm | 0.5 mm | sus 304 |
| H001-2 | o2-n | 34 mm | 9.85，15 mm | 8.9，14 mm | 0.5 mm | sus 304 |
| H003 | o2-n | 17.8 mm | 11.6，13.2 mm | 10.6，12.2 mm | 0.5 mm | sus 304 |
| H005 | o2-n | 14 mm | 16 mm | 15 mm | 0.5 mm | sus 304 |
| H009 | o2-n | 47.05 mm | 16，19.8 mm | 15，18.8 mm | 0.5 mm | sus 304 |
| H020 | o2-n | 8.5 mm | 18.25 mm | 14.5 mm | 0.3 mm | sus 304 |
| J009 | denso-heat-shields | 35.9 mm | 36，39.6 mm | 35 mm | 0.5 mm | sus 304 |
| J009-3 | denso-heat-shields | 4 mm | 36 mm | 35 mm | 0.5 mm | sus 304 |
| J010 | denso-heat-shields | 19.2 mm | 36，49.5 mm | 35 mm | 0.5 mm | sus 304 |
| J010-2 | denso-heat-shields | 10 mm | 36 mm | 35 mm | 0.5 mm | sus 304 |
| J011 | denso-heat-shields | 1.7 mm | 44.3 mm | - | 0.5 mm | sus 304 |
| J012 | denso-heat-shields | 17.5 mm | 35，60，65 mm | 64 mm | 0.5 mm | sus 304 |
| J014 | denso-heat-shields | 27 mm | 38.4，48 mm | 36.9 mm | 0.8 mm | sus 304 |
| J017 | denso-heat-shields | 25 mm | 35.9，58 mm | 34.3 mm | 0.8 mm | sus 304 |
| J017-2 | denso-heat-shields | 40 mm | 33.6，15 mm | 32 mm | 0.8 mm | sus 304 |
| J017-3 | denso-heat-shields | 23 mm | 33.6 mm | 32 mm | 0.8 mm | sus 304 |
| J017-4 | denso-heat-shields | 21.2 mm | 35.9，41.1 mm | 33.9 mm | 1.0 mm | sus 304 |
Why 304 is usually the first choice
304 (and its low-carbon 304L variant) draws well, resists the coolant, road salt and condensate a sensor housing sees, and is the most widely stocked austenitic sheet. Where a drawing does not name a grade, 304 is the sensible starting point and the one most likely to keep both tooling and material cost predictable.
What 304 does not solve
It is not a high-temperature exhaust grade (see 310S) and it is not magnetic (see 430). Deep draws that need a lot of deformation in one stage benefit from the low-carbon 304L or an intermediate anneal, because drawn 304 work-hardens.
How the route is decided
Draw ratio, wall thickness and the required concentricity decide the number of stages, whether an intermediate anneal is needed, and whether ironing is used to thin the wall while holding both diameters.