Refining and Petrochemical Sample Probe Assemblies
Sample probe assemblies for refinery and petrochemical units: crude distillation, hydrotreaters, FCC, alkylation, reformer, ethylene cracker, and aromatics. Material selection, NACE compliance, and high-temperature service.
Overview
Refining and petrochemical complexes are some of the most demanding sampling environments in industrial process. A single refinery may contain thousands of sample points spanning room-temperature naphtha streams to 900 °F catalytic reformer effluent, from sweet diesel to highly sour resid. The probe is the foundation of every analytical decision in the unit.
Unit-by-Unit Quick Reference
| Unit | Service | Material | Standard |
| Crude desalter | Wet brine, low °T | Duplex 2205 or C276 | API 14.1 |
| Atmospheric tower | 300-650 °F hydrocarbon | 316L | ASME B31.3 |
| Vacuum tower | Hot resid | 316L or Inconel | NACE MR0103 |
| Hydrotreater | High-pressure H2, sour | Inconel 625 | B31.12 |
| FCC reactor | Catalyst slurry, 950 °F | Inconel 625 + ceramic liner | API |
| Reformer | High-T H2, aromatics | Inconel 625 | B31.12 |
| Alkylation (HF) | HF acid | Monel 400 | NACE |
| Alkylation (H2SO4) | Hot H2SO4 | Tantalum or alloy 20 | — |
| Sulfur recovery | Wet H2S, SO2 | Inconel 625 | NACE |
| Aromatics | BTX hydrocarbons | 316L | B31.3 |
Failure Modes Most Common in Refining
1. Sulfide stress cracking at the gland in sour units
2. Hydrogen embrittlement in hydrotreater and reformer
3. Chloride pitting in desalter and overhead condensers
4. Wake-frequency fatigue in long probes on overhead vapor lines
5. Wax / coke buildup in resid and FCC service
Sampling Standards in Play
- API MPMS Chapter 14.1 for fiscal metering at the gate
- NACE MR0103 for refinery sour service materials
- ASME B31.3 for process piping
- ASME B31.12 for hydrogen service
- ASME PTC 19.3 TW-2016 for wake-frequency
Configurator Defaults for Refining
The SPA Configurator ships with a "refinery" application preset that defaults to:
- 316L SS or Inconel 625 (selectable)
- Solution-annealed condition
- NACE MR0103 statement on the bill of materials
- Heat-traced gland option pre-selected
- ASME PTC 19.3 wake-frequency check enforced