Huona J-Type Thermocouple Bare Wire SWG30/SWG25/SWG19 High Thermal Sensitivity
Type J thermocouple bare wire, a high-precision temperature-sensing element crafted by Huona New Material, consists of two dissimilar alloy conductors--iron (positive leg) and constantan (copper-nickel alloy, negative leg)--engineered for accurate temperature measurement in moderate-temperature environments. Available in three standard wire gauges: SWG30 (0.305mm), SWG25 (0.51mm), and SWG19 (1.02mm), this bare wire eliminates insulation interference, making it ideal for custom thermocouple assembly, high-temperature calibration, and applications requiring direct contact with measured media.
- Thermocouple Type: J (Iron-Constantan)
- Wire Gauges: SWG30 (0.315mm), SWG25 (0.56mm), SWG19 (1.024mm)
- International Standards: Complies with IEC 60584-1, ASTM E230, and GB/T 4990
- Form: Bare wire (uninsulated, for custom insulation/protection)
- Manufacturer: Huona New Material, certified to ISO 9001 and calibrated to national temperature standards
- Gauge-Tailored Performance: SWG30 (thin gauge) offers high flexibility for tight-space installations; SWG19 (thick gauge) provides enhanced mechanical strength for industrial environments; SWG25 balances flexibility and durability for general-purpose use.
- Superior Thermoelectric Accuracy: Generates a stable electromotive force (EMF) with a sensitivity of ~52 μV/°C (at 200°C), outperforming Type K in the 0-500°C range, with Class 1 accuracy.
- Bare Wire Versatility: No pre-applied insulation allows users to customize protection based on specific temperature/corrosion requirements.
- Cost-Effective: Iron-constantan alloy is more affordable than precious metal thermocouples while delivering higher sensitivity than Type K.
- Good Oxidation Resistance: Performs reliably in oxidizing environments up to 750°C.
| Attribute | SWG30 (0.315mm) | SWG25 (0.56mm) | SWG19 (1.024mm) |
|---|---|---|---|
| Conductor Material | Positive: Iron; Negative: Constantan (Cu-Ni 40%) | Positive: Iron; Negative: Constantan (Cu-Ni 40%) | Positive: Iron; Negative: Constantan (Cu-Ni 40%) |
| Nominal Diameter | 0.305mm | 0.51mm | 1.02mm |
| Diameter Tolerance | ±0.01mm | ±0.015mm | ±0.02mm |
| Temperature Range | Continuous: 0-700°C; Short-term: 750°C | Continuous: 0-750°C; Short-term: 800°C | Continuous: 0-750°C; Short-term: 800°C |
| EMF at 100°C (vs 0°C) | 5.268 mV | 5.268 mV | 5.268 mV |
| EMF at 750°C (vs 0°C) | 42.919 mV | 42.919 mV | 42.919 mV |
| Conductor Resistance (20°C) | ≤160 Ω/km | ≤50 Ω/km | ≤15 Ω/km |
| Tensile Strength (20°C) | ≥380 MPa | ≥400 MPa | ≥420 MPa |
| Elongation (20°C) | ≥20% | ≥22% | ≥25% |
| Item | Specification |
|---|---|
| Surface Finish | Bright annealed (oxide-free, Ra ≤0.2μm) |
| Supply Form | Spools (length: 50m/100m/300m per gauge) |
| Chemical Purity | Iron: ≥99.5%; Constantan: Cu 59-61%, Ni 39-41%, impurities ≤0.5% |
| Calibration | Traceable to NIST/China National Institute of Metrology (CNIM) |
| Packaging | Vacuum-sealed in argon-filled bags; plastic spools in moisture-proof cartons |
| Customization | Cut-to-length (minimum 1m), special alloy purity, or pre-tinned ends |
- Custom Thermocouple Assembly: Used by sensor manufacturers to fabricate probes with application-specific protection.
- Industrial Temperature Sensing: Direct measurement in food processing and plastic molding.
- Calibration Equipment: Reference elements in temperature calibrators.
- Automotive Testing: Monitoring engine block and exhaust system temperatures.
- Laboratory Research: Thermal profiling in material science experiments.
Huona New Material subjects every batch of Type J bare wire to rigorous quality testing: thermoelectric stability tests, dimensional inspection, and chemical composition analysis. Free samples (1m per gauge) and calibration certificates are available upon request.
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.