Case Study: One Day of Scanning Catches a Steel Conflict Before Fabrication

At a glance: ~20,000 sq ft captured · 1 day on site · ~100 scan setups · FARO Focus terrestrial · Deliverable: registered point cloud.

The challenge

A structural fabrication design for new steel at a chemical/catalyst manufacturing plant in the Greater Houston, TX area had already been produced off-site — without a current, field-verified survey of the existing structure. When the design reached the plant, it didn't match reality: the existing columns had base plates bolted to the concrete foundation and a cap plate at the top of each column, and the new design extended the replacement steel straight through as if that cap plate weren't there. The new fabricated steel had nowhere to land.

Remeasuring the structure by hand would have been slow, and still prone to the kind of gaps that created the conflict in the first place. The project team brought in DynamicJT to capture the existing structure as it actually stood, before another piece of steel got cut.

The approach

Over one day on site, DynamicJT's crew set up a FARO Focus terrestrial scanner roughly 100 times across a ~200 × 100 ft section of process corridor and pipe rack, working around live plant operations in the middle of a Texas summer — vapor clouds off nearby equipment and extended heat exposure were part of the job, not an exception to it. No escort was required (the crew already carried the site's required safety training), and no confined-space work was involved — but every setup happened alongside an operating unit, not a shut-down one.

One honest note for anyone scoping a similar job: setup density matters more than it looks like from the outside. Closer spacing between setups on a run like this would have tightened the registration further — worth planning for on any project in a similarly congested corridor.

The scan wasn't tied to external survey control or georeferenced to site coordinates — for this project, the goal wasn't absolute geographic position, it was reconciling new steel to the steel already standing, and a local coordinate system tied to the existing structure was the right scope for that.

The deliverable

DynamicJT's deliverable was a single, registered point cloud of the existing columns, base plates, and cap plates — the as-built reference the project's engineering team needed to see what the original design had missed. From there, the engineering team used the point cloud to design new connections that reused the steel already fabricated rather than scrapping it, tying the new horizontal steel into the existing columns with angle clips at the web and flanges, and to produce detailed fabrication drawings and a bill of materials.

The outcome

The conflict was caught and resolved at the desk, before another piece of steel was cut — not after it arrived on site and didn't fit. The point cloud and field documentation meant the engineering team could work the fix without scheduling repeat site visits every time a question came up, which is where a project like this usually loses the most time. The plant's project manager and operations/safety team coordinated site access for the scan crew; no executive or procurement sign-off was needed to move the work forward — this was a technical fix, resolved at the project-management level.

Frequently asked questions

How long does an as-built scan like this take on site?

For a corridor and pipe rack section around 20,000 sq ft, one day of terrestrial scanning was enough to capture roughly 100 registered setups. Larger or more congested areas take longer — your scan crew should confirm timing against your specific footprint before mobilization.

What's the difference between the point cloud you deliver and the fabrication drawings my engineering team needs?

DynamicJT delivers a registered point cloud — and, when scoped, a 3D model built from it — documenting existing conditions as they actually are. Turning that into fabrication drawings, connection design, or a bill of materials is engineering work that belongs with your design team; the point cloud is what lets them do that work accurately instead of guessing.

Can you scan safely inside a live, operating plant?

Yes. Terrestrial scanning is passive and non-contact, and DynamicJT's field crews carry the safety training required for live-plant work. Site-specific requirements (escort, confined space, PPE) are scoped with your safety team before mobilization.

What if my original design was based on drawings instead of a field-verified survey?

That's a common failure point on brownfield and retrofit projects — a design built from as-designed or as-planned documents, not the structure as it actually stands, often misses site-specific conditions like an existing cap plate, an out-of-tolerance column, or a conflict with adjacent piping. A field-verified point cloud closes that gap before fabrication, not after.

Do I need survey control or georeferencing for a project like this?

Not always. For an internal structural reconciliation — tying new steel to existing steel — a local coordinate system tied to the structure itself is often sufficient. Survey control and georeferencing matter more when the deliverable needs to sit inside a plant-wide coordinate system or integrate with other georeferenced data. Scope it with your project team before the scan.

What equipment do you use for tight-tolerance industrial work?

For this kind of structural reconciliation, DynamicJT uses terrestrial scanners — FARO Focus and Leica RTC360-class instruments — chosen for tight-tolerance documentation. DynamicJT also operates mobile/SLAM scanners for faster coverage of larger areas where that level of tolerance isn't the limiting factor; the instrument is matched to what the project actually requires.

Reconciling as-built steel against a new design before fabrication is a form of deviation analysis — catching conflicts on the desk instead of on site. It sits alongside DynamicJT's core 3D laser scanning and Scan-to-CAD/BIM services.

Planning a brownfield tie-in or steel reconciliation project?

Get your existing structure scanned before the next piece of steel gets fabricated, or see another industrial as-built case study.