TL;DR
A shutdown survey energy & utilities program delivers sub-millimetre alignment, fit-check, and as-built measurement during the fixed outage when a turbine, boiler, gas train, or pump set is taken offline. With a 660 MW coal unit losing roughly AUD $30,000–60,000 in spot-market revenue for every hour it stays down, survey work that drifts onto the critical path is the most expensive mistake on a turnaround. Industrial Spatial Solutions plans, pre-establishes control, and executes outage surveys across Australian power stations, LNG trains, and water utilities so measurement is never the reason the unit stays cold.
Key takeaways
- A major coal or gas turbine outage runs 4–8 weeks; a minor inspection outage 7–14 days; an LNG train turnaround 21–45 days. At AUD $30,000–60,000 per hour of deferred generation on a large unit, a single shift of survey rework can cost more than the whole survey scope.
- The highest-value outage scopes in energy are turbine-generator shaft and bearing alignment, condenser and diaphragm clearance, boiler-feed-pump and fan alignment, gas-train compressor and heat-exchanger fit-up, and rapid as-built laser scanning for tie-ins and spool fabrication.
- Turbine bearing lines are held to OEM tolerances of 0.02–0.10 mm — captured with a Leica AT960 absolute tracker to sub-0.015 mm point accuracy, an order of magnitude tighter than civil or mining alignment.
- A Leica RTC360 captures a full turbine hall or compressor station as-built in minutes per setup, against the hours a total-station pick-up would take inside a live critical path.
- Survey datums tie to MGA2020 / GDA2020 with AHD heights, or the plant's machine reference line, so outage measurements reconcile against design, OEM data, and prior alignment records.
Why energy outages demand precision surveying
Energy infrastructure runs continuously until it is deliberately stopped, because stopping it is enormously expensive. A 660 MW unit in the National Electricity Market that defers generation forgoes tens of thousands of dollars an hour at typical wholesale prices, and far more during a price event. An LNG train at Curtis Island or the North West Shelf defers cargo measured in millions per day. That is why turbine outages, boiler inspections, and gas-train turnarounds are scheduled to the hour months in advance — and why a shutdown survey energy & utilities scope that overruns is not a survey problem, it is a generation problem.
Outage surveying differs fundamentally from routine plant surveying. There is no slack in the schedule. The surveyor measures when the mechanical crew hands over the work front — not before, not after — and the result must be issued before the next activity starts. A turbine cannot be re-coupled until the bearing line and coupling alignment are signed off; a new heat exchanger cannot be set until the spool fit-up is verified; a condenser cannot be boxed up until tube-bundle and diaphragm clearances are confirmed. Survey is woven into the mechanical sequence, and a delayed measurement delays everything downstream.
The consequences compound fast. A turbine re-coupled on an out-of-tolerance bearing line runs hot, vibrates, and forces an unplanned re-stop — a multi-million-dollar event on a large machine. A compressor set on a misaligned baseplate sheds couplings and seals from the first hour of restart. The discipline that prevents this is unglamorous: pre-established control, a verified machine reference line, and a methodology agreed before isolation is granted.
| Do | Don't |
|---|---|
| Lock outage survey scope 4–6 weeks before the unit comes offline | Decide survey scope during the outage when the clock is running |
| Establish and verify the machine reference line before the plant stops | Try to set control in a congested, crane-blocked turbine hall |
| Tie every measurement to MGA2020 / AHD or the OEM datum | Mix arbitrary local datums between pre- and post-work surveys |
| Laser-scan the unit while it is open and accessible | Re-mobilise weeks later when the access window has closed |
Energy & utilities outage survey applications
Energy turnarounds concentrate the most demanding mechanical survey work into the shortest possible window. The applications below recur across coal and gas generation, LNG and gas processing, and water utilities.
Turbine-generator shaft and bearing alignment
The turbine-generator train is the single most survey-critical asset in a power station outage. ISS establishes a precision reference line, then surveys coupling alignment, bearing centreline, catenary, and soft-foot to the OEM tolerance — typically 0.02–0.10 mm across the bearing line. We capture the cold pre-outage condition, support the fitters through rotor lift and bearing work, and verify the line before re-coupling. Deliverables feed directly into the shimming and chocking plan.
Condenser, diaphragm, and casing clearance
During a steam-turbine major, ISS measures condenser tube-bundle position, diaphragm and gland clearances, casing parting-line geometry, and exhaust-hood alignment. These checks confirm the machine can be boxed up to design clearance before it is closed, avoiding rubs and efficiency loss that only surface at recommissioning.
Boiler-feed-pump, fan, and rotating-plant alignment
Beyond the main train, the survey-critical assets are the boiler feed pumps, ID and FD fans, mills, and gearboxes. ISS provides coupling alignment, baseplate flatness, and bearing centreline surveys for this rotating plant during the outage, so the balance of plant restarts cleanly alongside the turbine.
Gas-train compressor and heat-exchanger fit-up
In LNG and gas processing turnarounds, the work is compressor train alignment, heat-exchanger and vessel replacement fit-up, and pipe-rack tie-in verification. ISS provides dimensional control for compressor baseplates and nozzle positions, and rapid as-built capture so replacement spools and exchangers fit first time inside the turnaround window.
Rapid as-built laser scanning for tie-ins and replacement
When an outage involves new equipment, a tie-in, or a modification, the as-built condition must be captured while the plant is open. A Leica RTC360 captures a full turbine hall, boiler house, or compressor station in minutes per setup, producing a registered point cloud for clash detection, spool generation, and replacement-component fit-up. This is frequently the only window in which the asset is accessible, so comprehensive capture during the outage protects every future engineering project. See outage survey services for the full scope.
Key point: The outage is often the only time hot, congested plant is accessible for measurement. Scanning everything that is open — regardless of immediate need — turns a one-off cost into a reusable digital as-built that pays back on the next retrofit, audit, or capital project.
How ISS executes an energy outage survey
ISS structures every energy turnaround around a sequence that keeps survey off the critical path.
1. Scope definition (4–6 weeks out). We review the outage work list and schedule, flag every survey-dependent activity, and run a site visit to assess access, hazards, switching constraints, and reference-line requirements. The output is an agreed survey methodology and program.
2. Reference and control establishment (1–2 weeks out). The machine reference line and site control are set and verified against MGA2020 / GDA2020 with AHD heights, or the OEM datum, while the plant is still accessible and uncongested. Measurement is then available the moment the area is handed over.
3. Pre-outage baseline. Cold bearing-line positions, clearances, and alignments are captured as the reference against which post-work measurements are compared.
4. In-outage execution. The surveyor attends in sequence with the mechanical crew — continuous standby for tight bearing work, scheduled attendance for specific checks on longer turnarounds — measuring as each work front becomes ready and issuing results before the next step.
5. Post-outage verification and reporting. Final alignment and as-built confirmation before recommissioning, with deviation tables and point-cloud deliverables issued in your coordinate system and in E57, LAS, RCP and AVEVA-ready formats for downstream engineering.
ISS owns its trackers, total stations, and scanners, so there is no waiting on hire equipment, and crews hold current high-voltage awareness, switching-authority, confined-space, and EWP certifications for the live-plant environments we enter.
Equipment and tolerances
Outage survey gear must be reliable, portable, and suited to hot, congested, hazardous-zone plant. ISS deploys instruments calibrated to ISO 17025 with current certificates and carried with regional backups, so a single instrument fault never stalls a turnaround.
- Leica AT960 Absolute Tracker with T-Probe — sub-0.015 mm point accuracy for turbine bearing lines, coupling alignment, and machined-surface dimensional control.
- Leica TS60 / Nova total station — 0.5" angular accuracy with automatic target recognition for reference-line establishment, monitoring, and setout.
- Leica RTC360 laser scanner — around 2 million points per second at ±1.9 mm range accuracy at 10 m, for rapid as-built capture of turbine halls, boiler houses, and compressor stations.
- FARO arm and reflectorless measurement — close-range fit-check to inaccessible points without target access.
Typical tolerances on energy outage work: turbine and rotating-equipment alignment 0.02–0.10 mm; plant as-built scanning ±2–5 mm at 10 m; structural and baseplate setout in the low millimetres; control and reference networks at the millimetre level. Drone capture — flown by CASA Part 101 / CASR Part 101 certified operators under a current ReOC — supplements ground work for site-wide context, stack inspection, and switchyard documentation around the outage.
Regulatory and safety standards
Outage environments are among the most hazardous survey workplaces in the energy sector — confined spaces, residual heat, high-voltage exclusion zones, heavy lifting, and constant time pressure. Survey work sits across several standards frameworks, and ISS delivers data formatted for direct engineering and regulatory use.
| Standard / regulation | Scope | Survey relevance |
|---|---|---|
| AS/NZS ISO 9001 | Quality management | Traceability from field measurement to deliverable |
| ISO 17025 | Instrument calibration | Calibration of trackers, total stations and scanners |
| AS 3600 / AS 4100 | Concrete & steel structures | Foundation, baseplate and steelwork setout tolerances |
| AS 2885 | Gas & liquid petroleum pipelines | Route, tie-in and as-built survey for gas facilities |
| CASR Part 101 (CASA) | UAV / RPAS operations | ReOC and licensed crews for stack, switchyard and corridor flights |
Before mobilisation, ISS surveyors complete site-specific induction, task-based risk assessment, and the relevant confined-space, hot-work, and switching permits, and brief against the outage coordinator's communication plan. Coordinate and height work is referenced to GDA2020 / MGA2020 and AHD so survey data reconciles cleanly with design models, OEM records, and statutory submissions.
Key point: The most common outage survey failure we are called in to fix is not measurement error — it is access. A surveyor who cannot reach the reference monument because a crane is parked over it, or cannot enter the turbine casing because the permit is not raised, loses hours the schedule cannot give back. Planning access is survey work.
Frequently asked questions
What is a shutdown survey in the energy sector?
A shutdown survey energy & utilities scope is precision measurement carried out during a planned outage — a turbine major, boiler inspection, condenser overhaul, compressor change-out, or LNG-train turnaround. It covers pre-outage cold baselines, in-outage alignment and fit-check, and post-outage as-built verification before recommissioning. The defining feature is the fixed window: every measurement is sequenced against mechanical work so it never delays the restart.
How far ahead should we book an outage surveyor?
Four to six weeks before the unit comes offline. That allows scope definition, a pre-outage site visit, safety and switching documentation, reference-line establishment, and crew scheduling. Turbine majors and LNG turnarounds are planned months out, and survey should be locked in as soon as the work list is firm. Short-notice bookings risk unavailable crews and rushed planning when the cost of delay is highest.
What accuracy does ISS achieve on turbine alignment?
Turbine-generator bearing lines and coupling alignment are surveyed with a Leica AT960 laser tracker to sub-0.015 mm point accuracy, with alignment held to the OEM tolerance of 0.02–0.10 mm. Results are delivered as a deviation report that feeds directly into the fitters' shimming and chocking plan, so the line is corrected before re-coupling.
Can ISS work near live plant and energised switchyards?
Yes, within strict limits. We work live plant routinely, observing high-voltage exclusion zones, switching-authority requirements, and permit-to-work. Where ground access is unsafe or too slow — near energised busbars or in hazardous gas zones — we capture data remotely with laser scanning or UAV LiDAR from a safe standoff, planned with the site's switching authority.
Will survey work extend our outage?
Only if it is poorly planned. With the reference line pre-established and scope locked early, survey runs parallel to mechanical activities and stays off the critical path. ISS measures when the work front is ready and reports before the next step starts — the surveyor is never the reason the unit stays cold.
Request a quote
An energy outage is the wrong place to discover your survey support is under-prepared. ISS plans the scope, pre-establishes the machine reference line, mobilises inducted crews with our own trackers and scanners, and delivers alignment, fit-check, and as-built data inside the window — so your turnaround restarts on schedule. We support outages across coal and gas generation, LNG and gas processing, and water utilities Australia-wide, from the Latrobe Valley and Hunter to Gladstone, Kwinana, and Curtis Island. Call 0407 057 015 or request a quote online to scope your next turbine major, boiler inspection, or gas-train turnaround.
Related: Energy & utilities surveying | Outage survey services | Shutdown survey services Australia