What wall thickness can a deep drawn sensor housing hold?
Balford's published sensor housing configurations record walls from 0.25 mm to 1.00 mm, with 0.50 mm the most common value in the catalogue. The usable range depends on diameter, depth and grade: a small, shallow part holds a thinner wall than a deep, large-diameter one in the same material.
Wall thickness in the published catalogue
| Wall thickness (mm) | Configurations |
|---|---|
| 0.50 | 176 |
| 0.40 | 46 |
| 0.30 | 13 |
| 1.00 | 7 |
| 0.80 | 5 |
| 0.25 | 5 |
| 0.60 | 3 |
| 0.45 | 1 |
Three ways wall thickness changes in production
- Thinning during drawing. Material flows and stretches, so the wall of a drawn cup is not the thickness of the blank. Tool radius, clearance and lubrication decide how much thinning happens and where.
- Ironing. Where the wall has to be thinned deliberately while holding both the inside and the outside diameter, the part is ironed through a series of rings rather than drawn again. This is how thin-wall sleeves and solenoid housings are made.
- Machining after forming. Sealing faces, bearing seats and critical functional features are often machined after drawing, because that is where a tight tolerance is actually needed.
What to state on the drawing
- Nominal wall thickness and where it is measured (near the base, on the straight wall, or at a defined height).
- Whether the wall must be held through ironing, and which diameter is the datum.
- Finished surface requirement, because it decides whether the last operation is forming or machining.
- Temperature or corrosion environment, because that decides the grade - and the grade decides what the wall can do.
True 0.001 mm resolution applies only to selected key machined features and has to be confirmed against the drawing; a drawn wall tolerance is a different order of magnitude by nature of the process.