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A flare tip spends its life in the least forgiving spot on the plant. It faces heat, rain, salt-laden air, sour gas and the occasional emergency release that pushes it far beyond routine duty. Most of the damage happens slowly and quietly, and the first real warning is often a flame that will not stay lit. A structured inspection catches those changes while they are still cheap to fix.
Before anyone climbs anything, work from the ground with binoculars and, if you have access to one, a thermal imaging camera. This first pass is safe, quick and surprisingly revealing. Watch the flame in normal flaring; a stable flame held at the tip rim tells you a great deal about tip and pilot condition.
Check the configuration as well. If the flare is on purge only, the visual cues are different from a full relief event, and you should note which case you are looking at. Inspecting at dusk helps because pilots are easier to see. Take a photo from the same spot every time; comparing images over months is far more useful than any single observation.
Once you are at the tip, slow down and work methodically around the circumference. Most defects repeat themselves at predictable locations: weld toes, pilot supports, steam nozzle bosses and the tip rim itself.
Look for a rim that has become wafer-thin, sharp-edged or scalloped. Erosion accelerates with high exit velocities, liquid carryover and particulate such as catalyst fines or sand. Pilot orifices erode too, which leans the flame over and makes it easier to blow out. Inner sleeves and swirl vanes are worth a close look, as their profile governs mixing and smokeless performance.
Thermal cycling cracks show up first at weld toes and heat-affected zones. In sour service, high-temperature sulphidation can leave a scale that hides fine cracks, so clean the area before you judge it. Check the tip-to-riser joint, pilot and igniter mounting brackets and any boss welded onto the tip. Where access is difficult, remote visual inspection with a borescope or a drone survey can capture what the eye cannot reach.
A tip that is no longer circular, a sagging pilot arm or a bulged section all point to thermal stress or mechanical damage. Blockages are just as common, and easy to miss from a distance. Coke, iron sulphide scale, refractory spalling, ice and condensate can all restrict pilot or steam passages. Bird and insect nests in idle flare tips are a genuine and regular cause of pilot failure, particularly on flares that run on purge for long periods.
Pilots fail more often than tips do. A partially blocked pilot nozzle still produces a flame, which is exactly why it is dangerous: it looks healthy until the day the wind gets up and it goes out. Check the pilot tip for erosion and the wind shield for damage or distortion.
For igniters, confirm the ignition sequence works from the control room before you climb; there is no sense in sending someone up to diagnose a tripped signal. On flame front generator systems, inspect check valves, drain condensate from air and gas lines, and check the spark plug, ignition coil and timing. On high-energy spark igniters, check electrode gap, contamination and the condition of high-tension cable insulation. Flame detectors — thermocouples, ionisation probes, UV or acoustic devices — should be proven as a loop, including the alarm that lands in the control room.
Purge gas is quiet safety equipment. Too little risks burn-back inside the stack; too much wastes gas every hour of the year. Confirm the actual rate against the design figure, not the set point on the panel.
Steam rings and centre steam nozzles erode at the drilled holes and crack at the bosses. On air-assist flares, inspect blower inlet screens, impellers and dampers. Molecular seals, purge reduction seals and flame arrestors are frequent offenders: crimped metal elements coke and scale over time, quietly raising the purge demand. Do not forget structural items — guide wires, thermal growth guides, bolts, earthing straps, ladders and platforms are all part of the inspection.
Flare systems can hold trapped gas, and burn-back inside a stack is a real hazard. Never break containment or open a tip assembly without a permit, a gas test and the site's isolation procedure. Follow your own safe work practices and take engineering advice before any weld repair on pressure-containing or high-temperature components.
A monthly ground-level visual check suits most sites, with a detailed tip inspection at each major turnaround. The schedule should also respond to duty. Bring the inspection forward after an emergency relief event, a lightning strike or severe weather, and for flares in sour service, high-flaring-duty units or where liquid or particulate carryover is known.
Track flaring hours and pilot failure alarms. If pilots have tripped more than once between turnarounds, that is your interval telling you something. A fixed calendar date is a poor substitute for a risk-based frequency.
A checklist only earns its keep if the findings turn into work. Grade each defect as immediate, next opportunity or monitor, and note whether the flare was in service when you looked. Tip assemblies often have long lead times, so early identification of erosion trends feeds directly into spares planning and budget requests.
Keep the photos, keep the notes and keep the same method each time. Erosion that grows a millimetre a year matters far less than erosion that appears between two consecutive inspections. Consistency, not complexity, is what makes a flare tip inspection programme work.
Photo: stevepb / Pixabay
