A 10,000 lb Membrane.
A Space With No Room.
A wastewater treatment facility needed to relocate a 10,000 lb membrane — and the only route ran through an extremely confined space with walls of uneven height. A standard gantry couldn't fit a run where the two sides aren't level, and a permanent overhead crane meant an expensive structural install for what was essentially a single move. eme engineered a custom 11000R aluminum gantry crane with one leg considerably shorter than the other, both legs running on tracks fixed to the concrete deck and the concrete wall. The membrane was repositioned — no permanent crane required.
- ASME B30.17 Cranes and Monorails
- CSA B167 Overhead Travelling Cranes
- Aluminum Design Manual (ADM) US aluminum structural design
- CSA S157 Strength Design in Aluminum
Every gantry is proof-load tested to 125% of rated capacity before shipment, so each one ships with applicable product documentation: an engineer-stamped drawing, a Certificate of Test at 125% of rated capacity, and a welded aluminum structure produced under CSA W47.2 certification by qualified aluminum welders. The custom 11000R built for this project was engineered and documented to the same standards as every other 11000 Series unit. The unequal-leg configuration required custom engineering review and full structural validation — a separate buckling analysis for the shorter leg, revised lateral-stability analysis, and support conditions evaluated independently at each leg — and the finished crane was load tested on site before commissioning.
- Industry
- Water & Wastewater
- Application
- Relocating a 10,000 lb membrane through a confined space with uneven wall heights
- Equipment
- Custom eme 11000R Aluminum Gantry Crane — one short leg, both legs track-mounted
- Constraint
- Extremely confined space; uneven wall heights; a permanent overhead crane not cost-justified for a single move
- Result
- Membrane relocated — no permanent overhead crane installation required
A 10,000 lb Membrane That Had to Move.
A wastewater treatment facility needed to relocate a filtration membrane weighing 10,000 lb. The component itself was straightforward to rig — the problem was everything around it.
The membrane had to travel through an extremely confined space: the kind of tight, built-in plant area where a treatment facility packs equipment around fixed concrete structures. There was no room for a crane truck, and no overhead lifting point already in place.
A Confined Space — With Walls That Didn't Match.
The space wasn't just tight. The walls bounding the membrane's path were of uneven height — one side higher than the other.
That rules out a standard gantry crane immediately. A catalog gantry has two legs of equal length, sized for a level run across a flat floor. Set one leg on a low surface and the other on a high one and the beam no longer sits level — the crane simply doesn't fit a space where the two sides aren't the same height.
The obvious alternative — installing a permanent overhead crane — meant a significant structural installation and the expense that comes with it. For a facility that needed to reposition one membrane, a permanent crane was a large fixed cost for a job that didn't justify it.
A Custom 11000R Gantry — One Leg Short, Both on Tracks.
eme engineered a custom eme 11000R aluminum gantry crane — the 11,000 lb capacity tier — built specifically to the geometry of this space:
- One leg was built considerably shorter than the other — so the top beam stayed level even though each leg landed on a surface at a different height.
- Both legs ran on tracks: one track fixed to the concrete deck, the other to the concrete wall. The gantry travelled the membrane along a fixed, controlled run line.
- The crane repositioned the heavy membrane through the confined space without any permanent overhead infrastructure being added to the building.
"Because of the tight space, one leg of the crane needed to be considerably shorter than the other."
It is the same engineering eme applies to its catalog gantries — aluminum structure, rated lifting capacity, applicable standards — adapted to a space no standard crane was shaped for.
Custom Geometry. Catalog Engineering.
- A short leg fit a space a standard gantry couldn't. The walls on either side of the run were different heights. Building one leg considerably shorter than the other kept the beam level across an uneven space — the single change that made the lift possible.
- Track-mounted legs turned a confined space into a controlled path. Tracks on the concrete deck and the concrete wall gave the gantry a fixed, repeatable run line — precise travel in a space with no room to steer.
- 11,000 lb rated capacity covered the 10,000 lb membrane. The custom build started from the 11000R — eme's 11,000 lb capacity tier — so the 10,000 lb membrane sat within the crane's rated capacity.
- No permanent overhead crane, no permanent cost. The custom portable gantry did the job a fixed overhead crane would have — without the structural installation and the expense of permanent infrastructure for a single relocation.
- Aluminum kept the custom crane workable. An aluminum gantry is light enough to install and handle inside a tight plant space — the same portability advantage that applies across the eme line, here in a one-off custom build.
Got a lift in a space nothing standard will fit?
Tell us the load, the space, and the constraints — uneven floors, low headroom, fixed structures, no room to maneuver. eme engineers custom aluminum gantry configurations for the lifts a catalog crane can't make.