Nautilus LLC products

The 660 Ultra Low Head turbine (660-ULH) is a 150mm (6in) diameter Francis turbine with a bronze runner and bronze and stainless steel guide vane and gate assembly. It uses a water lubricated rubber bearing below water and heavy duty spherical roller bearings above water to support the shaft and pulley assembly. The turbine case is fitted with an adjustable cylinder gate to turn the unit off and regulate flow.

The T Ultra Low Head turbine (T-ULH) is the most powerful open flume turbine built by Nautilus. This unregulated design produces from 500 watts to 3,300 watts with a head range from 1m to 3.7m. Often two or three units are installed to match streamflow variation or the T-ULH is installed in combination with the Regulated CMC. For large open flume environments, where it is not possible to drain the pit, an optional cylinder gate is installed to shut down the turbine. This is an external cylinder and it helps to clean leaves and debris from the turbine when opened and closed. Like the CMC-ULH, the T-ULH is designed with runner passageways that are larger than the guide vane openings to avoid clogging.

The regulated CMC Ultra Low Head turbine (CMC-ULH) operates in a similar power range as the 660-ULH in an open flume and produces up to 1500 watts. The CMC offers better part gate regulation and efficiency than the other cylinder gate Nautilus models.