Thrustmaster of Texas, Inc., pioneered the concept of hydraulic propulsion for the marine industry using technology originally employed in the offshore oil fields. Thrustmaster's hydraulic bow and stern thrusters are the benchmark for efficient and reliable maneuvering under severe marine conditions.
The hydraulic drive is extremely resistant to damage. Foreign objects ingested by the tunnel, (a disastrous event with a mechanically-driven bow thruster) will not damage the hydraulic drive train, as the hydraulic system instantly relieves any transmission overloads.
The variable-flow hydrostatic drive system allows for infinite propeller speed control in port and starboard direction. This allows perfect vessel station-keeping as well as instant thrust response. Full thrust can be reversed within three to five seconds. This instantaneous and fully proportional speed control gives performance better than a controllable pitch propeller (CPP) without the cost, complexity, fragility or maintenance problems of the intricate CPP control system with all its drive shafts, levers and feedback mechanisms.
Thrustmaster hydraulic tunnel thrusters require no routine maintenance, and rebuilds are recommended only once every 40,000 hours of operation.
Thrustmaster's hydraulic drive is simple, quiet, efficient and extremely smooth. The prime mover driving the hydraulic pump can be a non-reversible electric motor or an engine running at constant speed because the hydraulic transmission controls propeller speed and direction of rotation. The prime mover drives a hydraulic pump. The propeller is driven by a hydraulic motor. In between are fluid conductors. There are no drive shafts, gears, bearings or other mechanical components to fail. The hydraulics are virtually maintenance free and provide years of reliable operation while performing in the harshest marine environments.
Many Thrustmaster tunnel thrusters have been in continuous commercial use for more than 20 years, providing flawless operation without any component failures.
There are very few rotating parts. The simple design of the direct hydraulic drive, without right angle gear transmission or drive shaft, provides for extreme reliability and very easy maintenance. There is no scheduled maintenance to the tunnel thruster other than normal maintenance to the hydraulic system and prime mover. Because all bearings are lubricated by the hydraulic fluid, there are no grease points or oil levels to check. The hydraulic transmission separates and dampens engine and propeller vibrations.