How Drones Can Benefit Refineries: Stack and Pipe Inspections

Can drones for refineries really replace climbing and crane work?

For many of the surveys that now pull crews onto flare stacks, pipe racks and other tall process structures, the answer is yes, at least for the first look. Drones for refineries fly the steel, insulation, coatings and piping runs from the air, so the inspection team sees the condition without anyone climbing or hanging from a rope. Work that once needed a crane, a scaffold or a rope access team can often be flown in a fraction of the time.

The practical gain for an operator is fewer hours at height, fewer people in the work zone and less waiting on heavy lifts. A survey of a tall stack or a long overhead run that once meant days of setup can be flown in a shift, and the imagery reaches the inspectors the same day. The drone does not replace the inspector. It gives the inspector a clear view, sooner, of places the crew would otherwise have to reach.

We act as the integrator here. We choose the aircraft and sensors that fit your site, set up flight plans and data handling, train the staff who receive the imagery, and keep the program serviced. Every program starts with a free site assessment, so the plan is built around your structures, your airspace and your turnaround schedule.

How many refineries are there in the US, and who staffs them?

According to the U.S. Energy Information Administration, there were 130 operable petroleum refineries in the United States on January 1, 2026, down from 301 in 1982. The Gulf Coast holds most of the capacity. A refinery statistics compilation citing EIA data reports that the Gulf Coast had 58 refineries and about 54 percent of US capacity, with Texas at 34 and Louisiana at 15.

The people who run these sites are a smaller group than the footprint suggests. O*NET, which draws on Bureau of Labor Statistics data, reports 32,900 employees in refinery operator, pump system operator and gauger jobs in 2025, with projected job openings of 2,700 from 2025 to 2035. Projected growth for that occupation is in the decline category, at negative 1 percent or lower. Operators run units around the clock, so every hour a crew spends on a stack is an hour taken from the people who also run the unit.

What does inspecting stacks and piping cost crews today?

Flare stacks, vent stacks and long pipe racks are inspected by people who have to get to them. Crews set up scaffolding, book a crane for a lift, or send a rope access team up or down the structure. Each method puts people at height, and each needs setup time, permits and a plan for the people working below.

The exposure is the part operators worry about most. One drone inspection vendor describes rope access teams facing falls, fatigue and exposure to H2S or other toxic gases. The vendor view is one-sided, but the hazards it names are the ones a safety lead already plans around on every climb.

Another vendor reports a reduction in safety incidents of 30 to 40 percent within the first two years after drone implementation. That year is not verified, so treat the figure as the vendor's claim and check it against your own incident log before you use it in a budget conversation.

What are the main benefits for a refinery?

The clearest gain is time on the structure. A drone vendor's case study describes a contractor inspecting a 200-foot in-service flare stack at a California refinery, finishing the drone survey in 2 hours, where the traditional method using a tall crane could take up to 3 days. The same case says the drone reduced crew size and removed the need for crane operators and additional technicians. It is a vendor report, so use it as a benchmark to test, not a promise.

Other case evidence points the same way. A drone inspection case covering a gas terminal in Scotland, with flare stacks and wind gusts up to 40 mph, reports a survey finished in just over a day, where the reporter said it would have taken three workers three days, and it was done without a shutdown. A vendor blog says drones replaced crane-hoisted visual inspections of structures up to 90 meters at one refinery site, taking roughly one hour.

Downtime is the other gain. A refinery statistics compilation citing EIA data reports that US refineries ran at 92.0 percent of capacity on average in 2025, up from 90.5 percent in 2024. When a plant runs that close to full, a turnaround window is tight, and a survey that finishes in a shift rather than a week gives the planning team more room.

How does the drone work day to day?

A drone survey starts with the flight plan. The team lays out the structures, the flight altitude and the sensor passes, then checks wind and the flare status before anything leaves the ground. A trained pilot flies the mission, and the sensors record visual imagery and, where the job calls for it, thermal imagery. Thermal sensors record actual temperature, which helps the inspector spot hot spots and heat loss on a structure.

Thermal drones can inspect flares while they are in active operation, according to one drone inspection vendor. That matters at a refinery, because a flare cannot always be taken out of service for a look. After the flight, the inspector who owns the asset reviews the imagery and marks anything that needs a close contact check, which a crew then schedules.

Some sites want repeat passes on a fixed schedule rather than a single survey. A second vendor describes autonomous drones housed in weatherproof boxes that can operate remotely with around-the-clock monitoring. That setup suits a site with a standing inspection routine, though it still needs people who review the results.

Which areas of a refinery does the drone cover?

Coverage follows the structures that are hardest to reach. Flare stacks and vent stacks come first, since they are tall and their condition is hard to judge from the ground. Pipe racks and overhead piping come next, because the runs are long and cross roads, pipelines and other units. Tank tops, dikes and cooling tower structures can often be flown on the same mission when the site layout allows it.

Drones for refineries are not limited to a single unit. A site-wide plan sorts structures into those flown on a routine schedule, those flown only before a turnaround, and those left to existing crews. A vendor blog notes that contracting drone services avoids significant capital expenditure on drones, sensors, software and training, and that in-house teams can become more cost-effective for frequent, routine inspections. Which side of that line a site falls on is a real choice, and the assessment helps make it.

How does the drone work alongside existing staff?

The drone does not operate alone, and it does not replace the operators on the unit. The site keeps its operators, its inspectors and its maintenance crew. What changes is who has to be at height. On a typical flight the people on the ground are the pilot, a visual observer and the inspector who reviews the data, and the crew who would have climbed the stack is not sent up for each pass.

Training matters here. We train the staff who will receive and act on the data, so the inspection team can read the imagery, flag what needs a close look and record it in the usual way. Crew size shrinks for the survey itself, which is the change the vendor case reported, but it does not drop to zero. A refinery always keeps people on site who know the unit, and the program is built around them.

What drives the savings, and how big are they?

Savings come from three places: fewer hours at height, less time waiting on lifts and shorter survey windows. The hours are where the difference shows. The 2-hour stack survey compares with up to 3 days by the traditional method, and the gas terminal survey finished in just over a day where three workers would have needed three days. Those are per-job figures from vendor case studies, not annual totals, and your site will differ.

On cost, the figures in circulation come from vendors. One vendor reports that drone inspections reduce inspection costs by 60 percent versus rope access. In one North Sea case, the operator replaced 80 percent of rope access inspections with UAV flights over 12 months, and the same vendor attributes a 98 percent on-stream reliability factor to early corrosion detection from thermal drone surveys. The vendor also says a facility-wide program commonly documents 40 to 60 percent savings versus rope access.

Treat those as a range to test, not a forecast. The quickest test is to count your own hours. Take the last survey of one stack, add the crane days, scaffold build, rope team time, permit hours and reporting time, then compare that with the time a drone survey would take. Our assessment does that count with you before any quote.

What can a drone not do at a refinery?

A drone sees the outside of a structure. It does not replace contact inspection where the job needs a probe, a wall measurement or a sample. Corrosion under insulation, wall thickness and internal condition still need the methods the site already uses. The drone helps by showing where those checks are most needed, but thermal and visual imagery are a screen, not a final verdict.

Weather and airspace set limits. Wind can stop a flight, and the gas terminal survey mentioned earlier was flown in gusts up to 40 mph, but the call on any given day belongs to the pilot, and some days will not be flyable. Flights near a refinery also need authorization. A vendor blog notes that drone providers often handle FAA waivers or BVLOS approvals, which reduces the administrative load on the site.

How do you get started?

Start with a free site assessment. We look at the structures on your list, the flight paths, the airspace and the schedule around turnarounds, then pick the drone and sensors that fit that site. Nothing is quoted before that visit, because the right answer depends on the stacks and piping you actually have.

Robots are leased through financing, and the payment comes in the quote after the assessment. The quote covers the equipment, deployment and integration, staff training and service across the country. Bring your last survey hours and your structure list, and the quote will reflect your refinery rather than a generic plan.

Once the program is approved, we set the flight plans and data handling, train the staff who receive the imagery and support the first live surveys. The goal is a program your team runs with confidence, with a drone team on hand whenever it is needed.