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Sizes and tolerances
Diameter range, the tolerance we can hold on each band, and the mechanical values that come with the wire.
Diameter and tolerance
| Diameter band | Finished tolerance | Grade | Typical use |
|---|---|---|---|
| 0.05 – 0.20 mm | ±0.005 mm | Fine, diamond-die drawn | Response-critical and fine sensor work |
| 0.20 – 0.50 mm | ±0.008 mm | Fine | Small probes, cable cores |
| 0.50 – 1.50 mm | ±0.010 mm | Standard | General thermocouple and extension wire |
| 1.50 – 3.20 mm | ±0.020 mm | Standard | Heavy industrial, furnace assemblies |
Tolerance is quoted on the finished dimension, measured in-line. It is not a drawing tolerance that gets re-checked at packing.
Mechanical values
| Grade and leg | Tensile strength | Elongation |
|---|---|---|
| K — positive leg | ≥ 500 N/mm² | ≥ 20% |
| K — negative leg | ≥ 450 N/mm² | ≥ 20% |
| N — positive leg | ≥ 550 N/mm² | ≥ 20% |
| N — negative leg | ≥ 500 N/mm² | ≥ 20% |
| J, T, E — both legs | Reported per lot | Reported per lot |
Values are the minimum we quote on the certificate. The lot result is printed next to the minimum so the buyer can see where that lot actually landed.
Size and what it changes downstream
- Halving the diameter roughly quarters the response time of the finished sensor and roughly quadruples resistance per metre — the buyer sizing a circuit should ask for the resistance value, not extrapolate it.
- Fine sizes go on a spool and feed a strander without re-spooling; heavy sizes arrive on a coil for cutting at the customer's end.
- Non-standard diameters between 0.05 and 3.2 mm are drawn on request; below and above that band, ask before quoting.