are not only low in initial cost compared to other types of
absorption dynamometers, but they are also inexpensive to maintain.
Surfaces subjected to corrosion are amply protected, and
corrosion-resistant materials are selected. Due to the simplicity of
design, the brakes can be easily disassembled for periodic
models are provided with positive-type water shaft seals consisting
of a spring-loaded carbon ring operating against an optically flat,
stainless steel rubbing ring. These seals are operating
satisfactorily at speeds of 23,000 rpm. Hydra-Brakes® are usually
provided with ball bearings that can be lubricated with either oil or
grease, depending upon operating speeds. Means may be provided for
mounting bearing thermocouples, and a tachometer drive can be
furnished if desired. Also available are special flexible inlet and
discharge water fittings which eliminate long hose connections.