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Heavy Duty Type K KP/KN Bare Thermocouple Wire 3.0mm 3.2mm for Petrochemical High Temperature Monitoring
Product Details
| Grade | Type K | Standard Diameters | 3.0mm / 3.2mm (±0.02mm) |
|---|---|---|---|
| Thermoelectric Power | ~40.5 µV/°C At 100°C | Accuracy Class | IEC Class 1 |
| Continuous Operating Temp | -200°C ~ 1260°C | Tensile Strength | ≥700 MPa |
| Elongation | ≥20% | Surface Finish | Annealed Bright (pre-oxidized Optional) |
| Highlight | Type K thermocouple wire heavy duty,KP/KN thermocouple wire for petrochemical,High temperature monitoring thermocouple cable |
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Product Description
Type K Thermocouple Bare Wire (KP/KN) – 3.0mm / 3.2mm Heavy-Duty Grade
Product Overview
This heavy-gauge Type K thermocouple bare wire from Huona is a high-performance industrial-grade thermoelectric pair, engineered for long-term, continuous high-temperature monitoring in the harshest environments. Composed of KP (Chromel-A, positive leg) and KN (Alumel, negative leg), this robust wire is specifically designed to resist oxidation, thermal fatigue, and mechanical degradation, delivering stable, drift-free readings in 24/7 industrial operations. Unlike finer-gauge wires, its substantial cross-section drastically slows the aging process, ensuring reliable service life even at extreme operating temperatures.
Domestic & International Equivalent Grades
- Alloy Grade: KP (Chromel-A, Ni90Cr10) / KN (Alumel, Ni95AlMnSi)
- Standard Designations:
- IEC: Type K Thermocouple Wire
- ASTM: Type K, Grade 1/2
- DIN: KP / KN
- Brand Equivalents: Omega Chromel®-A / Alumel®, Isabellenhucht KP/KN
Core Material & Dimensional Specifications
- Product Name: Type K Thermocouple Bare Wire (KP/KN Pair, Heavy-Duty)
- Alloy Composition:
- KP (Positive Leg, Chromel-A): Ni ~90%, Cr ~10%, controlled impurities
- KN (Negative Leg, Alumel): Ni ~95%, Al ~2%, Mn ~2%, Si ~1%
- Standard Diameters: 3.0mm / 3.2mm (customizable: 2.0–6.0mm)
- Diameter Tolerance: ±0.02mm
- Form: Continuous coil (standard length: 25m/leg; custom lengths available)
- Surface Condition: Annealed bright finish (pre-oxidized option available for high-temperature use)
- Packaging: Coil form, bundled with anti-oxidation wrapping
Electrical & Thermal Performance Parameters
- Thermoelectric Power: ~40.5 µV/°C at 100°C
- Accuracy Class: IEC Class 1 (±1.5°C or ±0.4% of reading, whichever is greater)
- Operating Temperature Range: -200°C ~ 1260°C (continuous use; optimized for 800–1200°C long-term service)
- Thermal Stability: Minimal drift after 1000+ hours at 1000°C
- Tensile Strength: ≥700 MPa (KP/KN)
- Elongation: ≥20%
- Melting Point: ~1400°C (KP), ~1390°C (KN)
Key Differentiating Advantages
1. Ultra-Long Service Life in Oxidizing High-Temperature Environments
The 3.0mm/3.2mm diameter provides a massive material cross-section, drastically slowing the rate of oxidation and the infamous “green rot” degradation common in K-type wires above 800°C. This translates to 2–3 times longer service life compared to 1.0mm or thinner wires in identical conditions, eliminating costly downtime and frequent replacements in continuous-process furnaces.
2. Exceptional Mechanical Strength & Vibration Resistance
With a high tensile strength and robust cross-sectional area, this heavy-gauge wire is virtually immune to sagging, stretching, and breakage in vertical furnace installations or high-vibration environments like gas turbines and cement kilns. It eliminates the “wire fatigue” issues that plague finer gauges, ensuring structural integrity even under extreme thermal cycling.
3. Minimal Drift & Ultra-Stable Long-Term Readings
The larger material volume acts as a natural buffer against contamination and grain structure changes, resulting in minimal thermoelectric drift. This ensures process control remains accurate and consistent over thousands of operating hours, critical for maintaining product quality in steel, glass, and power generation applications.
4. Optimized for Heavy-Duty Probe Assembly
The thick diameter is ideal for constructing heavy-duty, high-temperature thermocouple probes. It provides ample material for robust weld junctions and is perfectly suited for use with large ceramic or metal protection tubes, making it a go-to choice for industrial OEMs and system integrators.
5. Enhanced Resistance to Contamination & Degradation
The Chromel-A positive leg, in particular, offers superior resistance to sulfur and carbon contamination compared to standard K-type alloys, making it suitable for use in environments with mild flue gas exposure, such as boiler exhaust systems and industrial kilns.
Technical Parameter Table
| Attribute | Specification |
|---|---|
| Alloy Grade | KP (Chromel-A) / KN (Alumel) |
| Standard Diameters | 3.0mm / 3.2mm (±0.02mm) |
| Thermoelectric Power | ~40.5 µV/°C at 100°C |
| Accuracy Class | IEC Class 1 |
| Continuous Operating Temp | -200°C ~ 1260°C |
| Tensile Strength | ≥700 MPa |
| Elongation | ≥20% |
| Surface Finish | Annealed bright (pre-oxidized optional) |
| Packaging | 25m coil/leg, anti-oxidation wrapped |
Supply & Packaging Standard
- Supply Form: Bare thermocouple wire pairs, continuous coils
- Packaging: Anti-oxidation paper wrapping + moisture-proof plastic bag, bundled coils for safe transit
- MOQ: 1 pair (sample order); bulk quantities available for industrial production
- Customization: Diameter, length, surface finish (pre-oxidized), and coil configuration available upon request
Typical Application Scope
- Steel & Metal Processing: Continuous monitoring in reheating furnaces, annealing ovens, and sintering plants operating above 1000°C.
- Power Generation: Boiler superheater, steam turbine, and exhaust gas temperature monitoring in coal-fired and gas-fired power stations.
- Cement & Kiln Operations: High-temperature sensing in rotary kilns, clinker coolers, and preheater towers.
- Petrochemical Refining: Process heater and reformer temperature control in harsh, sulfur-containing environments.
- Heavy Industrial OEM: Core material for manufacturing robust, long-life thermocouple probes for industrial machinery and process control systems.
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