Governing Fundamentals and Power Management phần 2 docx

Manual 26260 Governing Fundamentals and Power Management

Woodward 5

Chapter 2.

Hydro-mechanical Governors

Basic Hydro-mechanical Governor Components

The five fundamental components of a governor were mentioned in Chapter 1.

Now let’s take a closer look at how the basic hydro-mechanical governor works.

The key parts of a ballhead hydro-mechanical governor are:

• Speeder Spring

• Thrust Bearing

• Flyweights

• Pilot Valve Plunger

• Pilot Valve Bushing

• Oil Pumps

• Oil Pressure Regulation

• Servo (Power) Piston

• Compensation

• Drive Shaft

The Speeder Spring

The speeder spring is the part that sets the “desired speed”. Applying more force

down on the speeder spring causes the governor to increase fuel. This initial

force is usually set by the operator for the desired or “reference” speed. It can be

set by a screw adjustment, a knob, a lever, an electric motor, air pressure, or

solenoids, depending on the specific governor.

Figure 2-1. Speeder Spring

The design or shape of a speeder spring is critical to the proper operation of the

ballhead.

The speeder spring is generally shaped in a conical design. This shape helps

maintain a more rigid design so that it won’t buckle or flex to the side as force is

applied. There are other shapes of speeder springs that offer a variable force

over the length.

Some springs are designed to be close to a linear operation, and some are

designed to be non-linear depending on the specific governor. Most governors

use the linear-type speeder spring. The PG type governor uses a non-linear

speeder spring.