Oil, gas & chemical
with the details that matter.
Brownfield retrofits, pipe racks, tank farms, and turnarounds. We pair the capture method to the way your team will use the result.
What needs to be
measured first?
Process retrofit lives and dies on tie-in accuracy. Scanning the unit before the turnaround lets fabrication happen off site with confidence and shortens the critical path when the plant is down.
Every facility has a different risk surface. We start with access, geometry density, and the decision the capture needs to unlock — then choose between laser scanning, drone mapping, or both.
Talk through a scope- Brownfield retrofit
- Pipe racks
- Tank roofs
- Turnarounds
- Hazmat zones
- Site protocol
Scanning a process unit for retrofit and turnaround work
Brownfield process work is the original argument for reality capture, because the isometrics stopped matching the field somewhere around the third small modification. What gets captured, and how densely, is driven entirely by where the new steel and new pipe are going to land.
Tie-in points first
The handful of flanges, branches, and existing supports where new work connects to old are the geometry that must be right. Those get the densest setups, from multiple positions, so bolt circle orientation, flange face location, and the direction the line actually runs are all unambiguous.
Pipe racks and support steel
Rack levels, beam elevations, spare space in each tier, existing shoe and guide positions, and the structural members a new line will hang from. Rack congestion, not plot space, is normally what limits what a retrofit can physically add.
Equipment rows
Exchanger bays, pump rows, columns and vessels with their nozzle positions and platform steel, plus the maintenance envelopes around them — bundle pull space, davit swing, and the room a crew needs to break a flange.
Tank farms and containment
Shells, nozzles, manways, and connected piping from the ground, with the tank tops and bund geometry captured from the air rather than by sending anyone onto degraded roof plate or into the containment.
Access, scaffold, and laydown
Ladders, platforms, escape routes, and the ground space a scaffold or crane will occupy. Turnaround scaffolding is designed off this data long before the unit comes down, which is where much of the schedule saving actually comes from.
Permits, classified areas, and the pre-turnaround window
Process sites impose the strictest access rules we work under, and they are the ones that shape the plan. Site orientation, gas testing, hot work permits, and hazardous-area classification all have to be settled before a date is confirmed. In classified areas, whether a given instrument may be energized at all is a site decision governed by the area classification and your own equipment rules, so we scope those zones with your safety group rather than assuming access.
Scheduling almost always favours capturing while the unit runs. A pre-turnaround scan lets tie-ins be measured, spools fabricated off site, scaffold designed, and rigging checked in advance, so the outage is spent installing verified parts instead of discovering that a dimension moved. During the turnaround itself, the useful captures are the short ones taken the moment insulation comes off or a vessel opens — geometry that is visible for a few hours and then disappears again for years.
More on how this works in practice is on our guide to scanning without a shutdown.
From cloud to spool drawing
Process teams rarely want a whole-unit model. They want a small volume modeled to fabrication confidence and a large volume left as measurable cloud, and being clear about which is which is what keeps the modeling budget sane.
| The decision | What to ask for | Why that one |
|---|---|---|
| Fabricating a tie-in spool | Dense cloud plus a modeled tie-in zone | Fabrication needs flange face position and orientation modeled; the surrounding unit only needs to be measurable. |
| Routing new pipe through an existing rack | Point cloud with modeled rack steel and existing lines | Routing is a clash problem, and clash detection needs solids for anything the new line could hit. |
| Turnaround planning and scaffold design | Registered cloud with a documented coverage note | Planners measure clearances themselves; what they need most is confidence about what was and was not captured. |
| Site-wide plot and expansion studies | Aerial orthomosaic, surface model, and volumes | Plot space, road access, and laydown decisions are made at site scale rather than at flange scale. |
Formats and what each one is good for are covered on the deliverables page.
The things that ruin process scans
- Insulation measured as pipe — The scanner sees the lagging, not the line. Anyone modeling from the cloud has to be told the insulation thickness, or the model shows a 12-inch line where an 8-inch line with four inches of insulation actually runs — and the spool that follows will not fit.
- Tie-ins captured from one side — A flange scanned from a single position gives an ambiguous bolt orientation and a partly occluded face. Tie-in points are the cheapest place to spend extra setups and the most expensive place to be wrong.
- Scanning after the scaffold goes up — Scaffold blocks exactly the geometry it was erected to reach. If the capture happens after erection, the unit is documented with a temporary structure in front of everything that matters, and that structure is gone by the time the model is used.
- No coverage note — In a congested unit, some volume is always occluded. Without an explicit statement of what could not be seen, a modeler fills the gap with a plausible guess, and that guess is indistinguishable from measured data by the time it reaches a fabricator.
What process and reliability engineers ask
Can you scan inside a classified area?
That is a site decision, not ours to assert. Area classification, your equipment rules, and the permit system determine what may be energized where, so classified zones get scoped with your safety group before mobilization. Where an instrument cannot be taken in, the practical answers are capturing from the boundary, working during a de-classified window, or scheduling that area into the turnaround.
How accurate does a tie-in need to be?
Tighter than the rest of the unit, which is why tie-ins get their own setup plan. The honest answer is that achievable accuracy depends on range, incidence angle, surface, control, and registration quality on your specific site, so we agree the tolerance the fabrication actually requires up front and report measured residuals afterwards rather than quoting a number in advance.
Can the point cloud go into our plant design software?
Registered clouds are delivered in the exchange formats plant design and review tools read, and the coordinate system is agreed before capture so the data lands where your existing model expects it. Which format is right depends on what your engineering contractor opens, so that question belongs in the scope conversation.
Is it worth scanning a unit we are about to demolish?
Often yes. Demolition sequencing, material and metal inventory, environmental documentation, and the design of whatever replaces it all benefit from a record of what was there. Once the unit is down, no amount of budget recovers the geometry.
Pair TLS interiors with drone exteriors for one coordinate story.
Roof, yard, tanks, structures, and the building envelope can live in the same project handoff when the control is planned upfront.
See existing conditionsMake the invisible
measurable.
Tell us what is inside, outside, and on the line. We will help you scope the capture and the handoff — in New York, New Jersey, or Connecticut.
Request a scan quote