Three models for different operating environments, each with differing advantages and disadvantages.
CAST IN PLACE
In this design the trough must be cast in place in concrete and all components must be aligned upon installation (lower bearing/support, upper bearing, trough gap). Because the trough is cast in place in concrete, a stainless steal trough is used
- Freezing outdoor environment.
- Operates in freezing environments as part of an enclosed installation.
- Alignment needed of components upon installation.
- More complex installation due to increased site work and casting in place
In this design the trough is a closed tube. The screw, trough, bearings (upper and lower), gearbox and generator are all installed and pre-aligned in a self supporting structure.
- Non-freezing outdoor environments, generally for lower flow sites.
- Most Economical of all models because structural rigidity provided by tube.
- Simple and quick installation because only need upper and lower supports.
- Limited to available pipe and tubing sizes that are economical.
- If an item were to get lodged in screw within the pipe, it would be difficult to remove it.
- Not intended for freezing environments
- Not as visually attractive for viewing.
In this design the open top trough is roll formed steel supported by an external frame.
Just like the Closed Complete Model the screw, trough, bearings(upper and lower), gearbox and generator are all shipped as a single pre-aligned unit from the factory
- Non-freezing outdoor environments, generally for higher flow sites.
- 2nd most economical model.
- Simple and quick installation because only need upper and lower supports. This can mean much simpler concrete site work.
- Not intended for freezing environments.
- Necessary to enclose to some degree for safety reasons.