Match Temperature Measurement Range:
Type T (Copper-Constantan): -200~350℃ (high precision for low temperatures);
Type K (Nickel-Chromium-Nickel-Silicon): -200~1200℃ (general-purpose first choice);
Type S (Platinum-Rhodium 10-Platinum): 0~1600℃ (high precision for high temperatures);
Type B (Platinum-Rhodium 30-Platinum-Rhodium 6) for temperatures exceeding 1600℃.
Adapt to Ambient Medium: Prioritize Types K/S/B for oxidizing atmospheres; Types N (Nickel-Chromium-Silicon-Nickel-Silicon) or Tungsten-Rhenium series for reducing/vacuum environments; use protective sleeves (e.g., Hastelloy, corundum) in corrosive environments.
Balance Cost and Stability: Type K for regular scenarios (high cost-performance); Platinum-Rhodium series for metrology/high-temperature, strong-corrosion scenarios (long-term stability); Type T for low-temperature scenarios (high sensitivity).
Key Links in Quality Control
Material Purity Control: Electrode materials must comply with GB/T 16700 standard; Platinum-Rhodium series purity ≥99.95%, impurity content of nickel-based alloys <0.5% to avoid affecting thermoelectric potential stability.
Manufacturing Process Inspection: Check electrode wire diameter uniformity (deviation ≤±0.02mm), welding quality (no pores/cracks in welds, using argon arc welding), and intact, moisture-free insulation layers (magnesium oxide, aluminum oxide).
Calibration and Stability Testing: Calibrate per IEC 60584 before delivery, with thermoelectric potential deviation meeting grade requirements (e.g., Class Ⅰ: ±1.5℃ or ±0.004|t|); verify drift <0.5% through high-temperature aging test (≥100h).
Quality Control During Use: Conduct regular verification (once a year), avoid over-temperature operation, store in dry, non-corrosive environments, and ensure stable cold-junction temperature during installation (equipped with compensation wires/cold-junction compensators).