Five spec gates dominate 2026 gantry crane selection: rated capacity (SWL), span, lift height, FEM/ISO duty class, and power-supply topology — buyers who compress these into a single RFQ line routinely buy a crane that is 20–30% over-spec on price or under-spec on service life [S1][S3].
Gantry cranes split into single-girder, double-girder, semi-gantry, and mobile (rubber-tyred or rail-mounted) variants; portable aluminium units cap at roughly 2 t, while shipyard and rail-yard double-girder builds reach 500 t and beyond, with 1,200 t ship-building gantries on record [S1][S3]. Pricing tracks span, capacity and duty class almost linearly above the 10 t / 20 m threshold [S2].
Rated Capacity, Span and Lift Height — The Triangle That Drives Steel
SWL (Safe Working Load) is the single non-negotiable gate; a 10% margin over the heaviest regular load is the common engineering rule, with a 25% margin over the absolute peak load for occasional lifts [S3]. Under-speccing capacity shortens structural life and invalidates most FEM 1.001 / ISO 4301 duty-class assignments; over-speccing by 50% typically inflates wheel load, runway beam, and foundation cost more than the crane itself [S1][S3].
Span is measured rail-to-rail for full-gantry and track-to-wall for semi-gantry; standard single-girder spans run 5–35 m, double-girder 10–50 m, and heavy shipyard gantries cross 100 m+ [S1]. Lift height must include hook approach, sling compression, and a 0.5–1.0 m safety buffer above the tallest standing load — the gantry crane reference frame is the cleanest way to keep these three numbers self-consistent before any structural calculation is opened.
Duty Class, Hoist Group and the FEM 1.001 / ISO 4301 Map
Duty class is the gate most often fudged because it does not appear on the load itself. FEM 1.001 / ISO 4301 combine a hoisting class (e.g. 2m, 3m, 4m) with a travelling class (e.g. A5, A6, A7) into a single service designation; a workshop running two shifts with 6–10 cycles/h sits in FEM 2m/A5–A6, while a 24/7 scrap-yard or rail terminal needs 4m/A7 or 5m/A8 [S1][S3].
Hoist group determines wire-rope diameter, drum size, and motor thermal rating; travelling class sets wheel bearing life, gear-box ratio, and brake sizing. Buyers specifying “heavy duty” without an FEM designation routinely receive a 1Am/A3 machine labelled as industrial — that crane will fail inside 5 years in a port, but quietly pass a 1-year warranty [S3]. For buyers who also handle crawler-crane-rigged heavy lifts, the crawler crane spec frame gives a useful cross-check on load-chart discipline.
Power Supply: Conductor Rail vs Festoon vs Cable Reel
Long-travel power supply is the gate that controls uptime. Three topologies dominate 2026 builds: insulated conductor rail (busbar), C-track festoon with flat or round cable, and motorised cable reel [S3].
Conductor rail handles the highest cycle rates and the largest currents (typical 100–630 A copper/stainless bar systems), tolerates dust and outdoor weather when IP-rated, and supports speeds above 60 m/min; festoon systems are cheaper up front but limit speed (often to ~30 m/min) and require regular cable inspection. Cable reels suit long straight runs with infrequent travel; spring reels wear out faster in high-cycle service [S3]. The selection rule of thumb: 24/7 outdoor operation at >40 m/min almost always lands on conductor rail, indoor low-cycle work stays on festoon.
Mobility: Rail-Mounted vs Rubber-Tyred vs Stationary
Stationary rail-mounted gantries are the workhorse of stockyards, precast yards and shipyards: wheel loads are predictable, foundations can be engineered once, and travel drives can be sized for the precise cycle profile. Rubber-tyred mobile gantries (RTG and rubber-tyred straddle variants) add diesel or battery-electric drive steer; battery-electric RTGs have become the default for new container terminals as diesel-RTG phase-out accelerates in EU ports [S1].
For a single indoor bay that occasionally needs to clear the floor, a portable aluminium gantry on locking casters is the cheapest answer, but capacity caps at 2 t and span at about 6 m — anything heavier needs a real mobile crane or a fixed gantry with foundations. Buyers comparing against overhead-crane options in the same bay should also cross-reference the overhead crane family reference for the structural-bay compatibility map.
Selection by Use Case: Workshop, Yard, Port, Fabrication
Workshop / maintenance bay: single-girder, 1–10 t, span to match bay, FEM 1Am–2m, festoon power, top-running or under-running depending on headroom. Typical 2026 price band is the lowest among the four use cases [S2].
Stockyard / precast yard: double-girder, 10–50 t, span 20–40 m, FEM 2m–3m, conductor rail, rail-mounted on a dedicated runway beam. Wheels-per-corner counts double here because 8-wheel bogies halve the point load and let the runway sit on a lighter civil foundation [S1][S3].
Port / container terminal: rubber-tyred or rail-mounted container gantry, 30–65 t under spreader, FEM 4m–5m, conductor rail or cable reel on long travel, anti-collision and skew-detection mandatory. For adjacent yard-handling work, a stacker crane is the proper alternative for automated container stacks, not a manually driven gantry.
Shipyard / heavy fabrication: double-girder or gantry-truss, 100–500 t standard, up to 1,200 t for ship-building, FEM 5m+, conductor rail, often paired with multiple truck crane or crawler crane lifts underneath for tiered erection. Buyers in this segment also benefit from reviewing truck crane selection criteria because the two machine classes share load-chart and outrigger-pad logic.
Safety, Standards and the Gates Buyers Most Often Skip
Three gates sit outside the headline spec sheet and still kill projects: end-stop buffers, overload protection, and lightning / earthing. End-stop buffers must be rated for crane travel speed plus a 10% margin; overload limiters are mandatory in most jurisdictions above 1 t and need annual re-calibration [S1][S3].
Standards to lock into the RFQ: FEM 1.001 for duty class, ISO 4301 for classification, EN 15011 / EN 13000 for the structural and safety requirements, and the relevant electrical standard (IEC 60204-32 for crane electricals, plus ATEX where an explosive atmosphere is present). Outdoor cranes in corrosive marine atmospheres also need a documented surface-protection spec — hot-dip galvanising, C4 or C5 paint system per ISO 12944, or both [S1]. Buyers who skip these items usually discover them during commissioning, which is the most expensive moment to add them.
Comparison: Four Common Crane Classes Against the 2026 Spec Gates
For cross-equipment context, the same five-gate logic (capacity, reach/span, duty class, mobility, power) applies to other 2026 buying decisions such as motor grader vs bulldozer and skid steer vs backhoe loader — useful when a yard spec spans both lifting and earthmoving. [S1]
For sites that also need a crane scale integrated into the lifting gear, the scale must be specified to the same FEM duty class as the host crane or its warranty will not hold.
Trackable signals for the next buying window: published 2026 Q3 list prices from Australian and European distributors (currently [S2] is the cleanest side-by-side price/spec table), and updated EN 15011 / FEM 1.001 commentary from Nante Crane and similar OEM newsrooms — both flow into RFQ accuracy within a quarter [S2][S3].