# Petrochemical Thermocouple Wire

> Reformer tubes, distillation columns, reactor vessels, pipeline monitoring and flare stacks. Reliable thermocouple conductors for hydrocarbon processing.

## Applications

| Scenario | Requirement | Solution |
|---|---|---|
| Steam Methane Reformer Tubes | Catalyst tube wall temperature in hydrogen and syngas plants. 800-950 °C, hydrogen-rich atmosphere. Accuracy directly affects tube life prediction. | Type K or N, φ0.5–1.0 mm |
| Distillation Columns | Tray and overhead temperature in crude oil and petrochemical fractionation. Multiple measurement points per column for composition control. | Type K or J, φ0.5–2.0 mm |
| Reactor Vessels | Exothermic reaction temperature control in polymerisation, alkylation and hydro-processing units. Safety-critical — thermocouple failure can lead to thermal runaway. | Type K, φ0.5–1.5 mm, dual redundant |
| Pipeline Monitoring | Buried and above-ground pipeline temperature for flow assurance and leak detection. Long cable runs — consider extension wire voltage drop. | Type K or T, φ1.0–2.0 mm |
| Flare Stack | Continuous flare pilot flame verification and stack gas temperature. Exposed to weather, corrosive gases and thermal radiation from the flare. | Type K with sheath, φ1.5–3.0 mm |

## Considerations

| Factor | Guidance |
|---|---|
| Corrosion resistance | H₂S, HCl and sulphur compounds attack standard thermocouple alloys. For reformer and cracker service, specify MI cable with INCL600 sheath. For chlorine-containing streams, Type J is preferred over Type K. |
| Safety integrity | Many petrochemical temperature measurements are safety-critical (SIL-2 or SIL-3). Dual redundant thermocouples with independent cable runs are standard practice for reactor over-temperature protection. |
| Long cable compensation | Pipeline and tank-farm runs can exceed 500 m. Use extension-grade compensating cable with heavier conductors (φ0.8 mm or larger) to minimise loop-resistance error at the instrument input. |