Woodward’s UG-8PL is a compensated, isochronous governor for use with diesel, gas, and dual-fuel engines or steam and industrial gas turbines driving pumps, compressors, alternators, generators, etc. The UG-8PL governor has an integral oil reservoir (sump) and oil pump and does not require an external oil supply for its operation. The governor also has both a spring-driven ballhead assembly and laminated-spring ballhead drive to help reduce undesirable torsion vibrations which may be transmitted to the governor.
Speed setting of the UG-8PL governor is accomplished either manually or remotely by a pneumatic signal from a standard air pressure controller or from a manually operated air pressure regulator on a remote control panel. Either of two types of pneumatic speed setting mechanisms are commonly used with the UG-8PL governor—a direct type where speed setting increases with increasing pneumatic (control air) pressure, or a reverse type where speed setting increases with decreasing control air pressure.
A variety of auxiliary options may be incorporated in the UG-8PL governor:
The booster servomotor is an external, pneumatically-operated hydraulic accumulator for use where quick starting is desirable to conserve the starting air supply and/or in some marine applications using direct reversing engines to improve maneuverability of the vessel. The booster servomotor eliminates the normal time lag required for the governor oil pump to create sufficient pressure to open the fuel control at start-up by supplying a small volume of pressurized oil to the governor at the instant starting air is turned on. This allows the governor to open the fuel control quickly and thus minimize cranking time. See manual 36684 for more detailed information on the booster servomotor.
Load Limit Control
The load limit control is a manually adjustable linkage mechanism which may be incorporated in the governor for use in applications where it is desirable to limit the prime mover horsepower output (load) to a predetermined maximum value at a given speed. The load limit control accomplishes this by restricting the angular rotation of the governor output shaft and consequently, the flow of fuel or steam to the prime mover.
Magnetic Speed Pickup
A magnetic speed pickup may be incorporated in the governor to obtain an indication of governor speed without having to provide an additional mounting pad on the prime mover. See manual 36052 for more detailed information on the magnetic speed pickup.
Solenoid Operated Shutdown Assembly
The solenoid operated shutdown assembly may be incorporated in the governor to provide a means of automatically effecting prime mover shutdown in the event of equipment malfunction. The shutdown assembly can be adjusted to effect shutdown either when energized or de-energized. See manual 03013 for more detailed information on the solenoid operated shutdown assembly.
Pressure Actuated Shutdown Assembly
The pressure actuated (air, oil, water) shutdown assembly provides the same protective function as the solenoid operated shutdown assembly. The pressure actuated shutdown assembly can be adjusted to effect shutdown with either high or low signal pressure. See manual 36651 for more detailed information on the pressure actuated shutdown assembly.
In some applications, particularly on small prime movers, it may be necessary to reduce the compensation below the minimum value normally attainable with a standard governor so that the governor can be adjusted to more closely match the characteristics of the prime mover. To accomplish this, a large compensation piston of slightly smaller diameter is used which proportionally reduces the corresponding movement of the small compensation piston for a given movement of the large compensation piston.