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Robotic NDT • Boiler Wall-Thickness • Coal, Biomass & WtE

Robotic boiler wall-thickness inspections for coal, biomass and waste-to-energy units.

RESTinspect provides high-density ultrasonic wall-thickness inspections of waterwall and membrane wall tubes in coal-fired, biomass and waste-to-energy boilers. Our autonomous robots deliver complete thickness maps — without scaffolding or manual work at height — so you can plan outages and repairs based on full-coverage data instead of spot checks.

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Built for coal, biomass and WtE boilers.

Our robotic inspection service is designed around the realities of large thermal boilers: high temperatures, complex waterwall geometries, corrosive environments and tight shutdown windows.

We support owners and OEMs of utility-scale coal, biomass and waste-to-energy units. The goal is always the same: full-coverage wall-thickness data that makes tube leaks and forced outages less likely.

Coal-fired utility boilers Biomass & co-firing units Waste-to-energy / EfW boilers CFB & grate-fired units Life-extension & retrofit projects

From spot checks to full boiler wall maps.

Tube leaks in large coal, biomass and WtE boilers are rarely caused by “average” thickness — they are driven by local minima you do not see with a handful of manual UT points.

RESTinspect replaces low-sample campaigns with high-density robotic wall-thickness mapping of your boiler walls. The crawler moves across the surface and records thickness values at millimetre-level spacing, creating continuous 2D and 3D thickness maps for each section.

You gain a complete overview of tube condition in critical areas.

Our solution: NURA for coal, biomass & WtE boilers.

NURA is RESTinspect’s robotic crawler for autonomous, high-density ultrasonic wall-thickness mapping inside industrial boilers and confined spaces — without scaffolding or manual work at height.

For coal-fired, biomass and waste-to-energy boilers, NURA acquires wall-thickness data at a resolution down to 5 mm spacing, providing 0.1 mm-level thickness values across furnace waterwalls, outlet screens and selected tube bundles.

The crawler is compatible with ferromagnetic membrane walls and non-ferromagnetic tubes, so lower and upper furnace, outlet screens and other critical areas can be mapped in one consistent campaign — using the same grid, coordinate system and data quality level across your units.

Thanks to its modular design, NURA adapts to different wall types, tube geometries and local constraints. In addition to standard boiler membrane-wall layouts, the crawler can inspect between tubes with pitches down to approx. 6 cm, and it can be configured for large CTC spacing and flat surfaces. This makes NURA suitable for both classic utility-boiler architectures and modern high-density or mixed-geometry boiler designs.

High-density UT Confined-space ready No scaffolding Modular platform

Where we inspect in your boiler

Our robotic platform is tailored to coal, biomass and waste-to-energy boiler geometries. From lower furnace to outlet screens, we capture high-density wall-thickness data in the zones where leaks and tube failures are most likely to occur.

Robotic inspection on furnace waterwall

Furnace waterwalls (coal, biomass, WtE)

Full-coverage UT mapping of furnace waterwalls, including lower and upper furnace. The crawler follows vertical and curved wall sections, maintaining stable coupling and grid spacing.

  • Identify local hot spots and thin spots
  • Track corrosion/erosion per outage
  • Support targeted panel replacement instead of blanket repairs
Robotic inspection on large CTC spacing and flat surfaces

Large CTC spacing & flat surfaces

For tube rows with larger centre-to-centre spacing or flat plate surfaces, our robotic platform adapts its configuration to maintain a dense scan grid. This avoids complex custom tooling and reduces inspection time and cost while still delivering high-resolution wall-thickness data.

  • Flexible configurations for varying CTC distances
  • Efficient scanning of wide or flat surfaces
  • Compatible with pressure vessels and plate sections
Inspection of upper furnace and outlet screens

Upper furnace & outlet screens

Slagging, fly-ash erosion and thermal cycling drive complex damage patterns in upper furnace and outlet screens. The same robotic campaign covers these walls, giving one consistent dataset.

  • Continuous thickness data from lower to upper furnace
  • Early detection of thinning before tube leaks develop
  • Prioritisation of panels and screens for repair or replacement

How it fits into your outage

Our service combines the robotic platform with a structured inspection workflow and a dedicated data portal, so you get a turnkey wall-thickness campaign that fits your outage plan.

Together we define the walls and zones to be inspected, align on access and safety constraints, and integrate the inspection schedule into your shutdown. During the outage, our team executes the robotic scans and monitors data quality in real time.

After the campaign, wall-thickness maps and statistics are processed and uploaded to the RESTinspect Portal. Integrity, maintenance and engineering teams can review results, export Excel datasets and plan repairs directly on the heatmaps.

Ready to map your boiler walls?

Whether you operate a single unit or an entire fleet of coal, biomass and WtE boilers: RESTinspect delivers high-resolution wall-thickness data within a single outage — without scaffolding and without exposing personnel to hazardous environments.

Discuss your next outage