Gas Chromatography (GC)
This section is designed specifically for process analyzer technicians. Concepts are explained in the same order they appear in the field — from sampling and injection to timing, separation, backflush, and troubleshooting.
Focus is on how GC actually behaves in plants, not lab theory.
GC Core Learning Path
GC Basics
Working principle, major components, and basic flow path of a process gas chromatograph.
Start Here →GC Sampling System
Probes, filters, regulators, conditioning and why most GC problems start upstream.
Learn →6-Port Sampling Valve
LOAD vs INJECT positions, internal rotor logic, and common valve-related failures.
Learn →Timing, Sequencing & Control
Advanced GC Techniques
Heart-Cut (Dual Column)
Pre-column separation, cut window logic, analytical column routing and timing mistakes.
Learn →GC Failure Modes
Symptom → root cause → corrective action mapping based on real chromatogram behavior.
Troubleshoot →Technician Rule
When a GC misbehaves:
Sampling → Pressure → Valves → Timing → Electronics
Do not recalibrate until the physical cause is fixed.