2820A_311_G.pdf

Individual Manual Application Sheet

Technical Publications Number

2820A

Secton Applicability

SWBS Number 311 SWBS Element Title SHIP SERVICE POWER GENERATION

Section Identifier G

Equipment Functional Description

EG-B2P GOVERNOR/ACTUATOR -

SSDG (82570F)

CI Functional Description ESWBS Code Remarks

Planset Hulls

905-WMEC 905, 906, 907, 908, 909, 910, 911, 912, 913

JUSZO

8257OF

VVAP

EG-B2P

GOVERNOR/ACTUATOR

This Manual 8257OF Replaces Manual 82570 and Manuals 82570 A through E.

WOODWARD GOVERNOR COMPANY

WARN

READ THIS ENTIRE MANUAL AND ALL OTHER PUBLICATIONS PERTAINING TO THE WORK TO BE

PERFORMED BEFORE INSTALLING, OPERATING OR SERVICING THIS EOUIPMENT. PRACTICE ALL

PLANT AND SAFETY INSTRUCTIONS AND PRECAUTIONS. FAILURE TO FOLLOW INSTRUCTIONS CAN

CAUSE PERSONAL INJURY AND/OR PROPERTY DAMAGE.

the next letter inThe letter designation following the manual number is changed to alphabetical order when an important revision is made to the manual.

TEXT CHANGES ARE INDICATED BY A BLACK LINE ALONGSIDE THE TEXT.

Woodward Governor Company reserves the right to update any portion of this publication at any time. Information provided by Woodward Governor Company is believed to be correct and reliable. However, no responsibility is assumed by Woodward Governor Company for its use unless otherwise expressly undertaken.

� Woodward Governor Company, 1980 All Rights Reserved

TABLE OF CONTENTS

TITLE PAGE TITLE PAGE

SECTION 1

General Information Introduction Description

Governor/Actuator Direct and Reverse Acting Types Speed Droop External Shutdown Solenoid

Specifications Output Governor Drive Control Characteristics Pilot Valve Transducer Coll Hydraulic System

References

SECTION 2

Installation Procedures

Introduction Installation Linkage Adjustment Governor/Actuator Drive Oil Supply

SECTION 3

Principles of Operation

Introduction Actuator Control Governor Control Speed Droop

SECTION 4

Adjustments

Introduction Recommended Tools Preliminary Adjustments Governor Needle Valve Setting .. � Speed Droop Adjustment Centering Pilot Valve Plunger Speed Adjustment

General Information Setting Maximum Speed

Adjustments After Tests

SECTION 5

Maintenance

Introduction Troubleshooting Removing the EG-132P Disassembly Parts Check ........................... %.. 20 Assembly Manual Override Assembly (Optional) Lubrication

SECTION 6

Auxiliary Devices

Introduction Pneumatic Start Spring Driven Ballhead

PAGE FIGURE TITLE PAGETITLEFIGURE

1-1 EG-B2P Governor/Actuator 1-2 Outline Drawing EG-B2P

Governor/Actuator 1-3 Solenoid Shutdown Connection 3-1 Schematic Diagram EG-132P

Governor/Actuator 4-1 Speed Setting Adapter Plate 4-2 Actuator Test Circuit ................ 1.4 5-1 Pilot Valve Wrench 5-2 Ballhead. Disassembly 5-3 Check Valve Installation 5-4 Speeder Spring Parts Layout 5-5 Speeder Spring Subassembly 5-6 Governor Pilot Valve Assembly 5-7 Actuator Pilot Valve Assembly 5-8 Clamp Bracket Parts Layout, 5-9 Clamp Bracket Subassembly 5-10 Ballhead Parts Layout 5-11 Ballhead Cover Assembly 5-12 Ballhead Assembly 5-13 Buffer System Parts Layout 5-14 Needle Valve Assembly 5-15 Parts Layout, Pistons and Levers 5-16 Power Piston Assembly 5-17 Power Piston Linkage Assembly 5-17A Obtaining Rocking Motion in

Power Pistons 5-17B Raising Power Pistons 5-17C Dropping Power Piston 5-17D Removing Play in Power

Piston Assembly

5-17E Removing Play in Power Piston Assembly

5-18 Piston Placement 5-19 Piston Link Assembly 5-20 Base and Parts

5-21 Bushing Assemblies 5-22 Relief-Valve & Piston

Sleeve Assembly 5-23 Ballhead Assembly 5-24 Thrust Bearing & Spring

Seat Assembly 5-25 Centering Pilot Valve Plunger 5-26 Base Assembly 5-27 Transducer Parts Assembly 5-28 EG-B2P Governor/Actuator Wiring

Diagram 5-29 Plug & Transducer Installation 5-30 Clamp Bracket Assembly 5-31 Transducer Compression Spring

& Ratio-Adjustment Plate 5-32 Terminal Shaft Installation 5-33 Speed Droop Lever 5-34 Speed Droop Lever Assembly 5-35 Dial Plate & Seal Assembly 5-36 Speed Adjusting Shaft Assembly 5-37 Cover Assembly 5-38 Final Assembly 5-39 Final Assembly 5-40 Manual Override Parts Layout 6-1 Manual Override Assembly 6-2 Cover with Manual Override

Assembled 7-1 EG-B2P Exploded View

TITLETABLE PAGE

1-1 Specifications 4-1 Recommended Tools

LIST OF ILLUSTRATIONS

LIST OF TABLES

MECH

GOVERN

ADJU'

(CW TO

Hi SPEED --- �

STOP

-,-�TERMINAL

I SHAFT

""-�SPEED

SETTING

SHAFT

OIL DRAIN

(FOR

HORIZONTAL

MOUNTING)

USWA-43T

Figure 1-1. EG-132P Governor/Actuator

SECTION 1

GENERAL INFORMATION

ELECTRICAL CONNECTION

ANICAL FOR INPUT SIGNAL

OR SPEED

3TMENT

INCREASE)

INTRODUCTION

A description of the EG-1321? governor/actuator is given in this section. This information includes general information about the system, the available adjustments, and the different arrangements available.

DESCRIPTION

GOVERNORIACTUATOR

The EG-132P is a proportional actuator with a ballhead backup governor. The proportional actuator's terminal (output) shaft position Is directly proportional to the input signal to the actuator. The uses and functions of a proportional actuator are different and distinct from integrating types of EG actuators. To make a suitable governor system, the EG-132P actuator must be used with the 2301 or similar integrating electric circuit. By comparison, the EG-132C is an integrating actuator with the companion EG-A control box being basically a proportional amplifier.

While proportional actuators can be used in the same type of service as other actuator models, they are particularly well suited to engines operating in tandem to drive a common load. In such installations, one electric control can be used for two or more proportional actuators wired in series with the control's output, to furnish the same input signal to each actuator. Since each actuator receives the same signal, their output shafts take the same position and give each engine tire same fuel.

Externally, the EG-132P is similar in size and appearance to the EG-132C actuator. Internally, each has two sections: an electric actuator section and a centrifugal governor section. The centrifugal governor section acts as a backup governor in the event of failure of the electric control. The electric actuator section is different in function and construction. The actuator section of the EG-132P includes feedback linkage from its power piston to its pilot valve to give the proportional feature to the actuator.

The proportional actuator requires a continuous electric input signal (in contrast to the nominally zero input signal under steady-state conditions for integrating type actuators), Woodward 2301 electric controls are used to furnish the control input signal for the proportional actuator. The exact 2301 control used depends upon the operating scheme of the installation. Control assemblies are available to sense speed, frequency, load, and other combinations.

The essential element of the actuator section of the EG-B2P is an electro-hydraulic transducer which directs pressure oil to and from the power piston to actuate the fuel or steam control mechanism. The transducer consists of a solenoid attached to the pilot valve plunger to control oil flow to and from the power piston. The solenoid responds to the given output of the electric control, and, in so doing, moves the pilot valve, plunger down directing oil to the power piston.

Through connecting linkage, the power piston moves the terminal shaft of the actuator. The engine or turbine fuel linkage attaches to the actuator terminal shaft.

While strict linearity of terminal shaft travel versus load is not required, the linkage should be arranged to give the same degree for linearity afforded conventional speed sensing governors.

The centrifugal governor section has three operating adjustments. Once set, these adjustments do not usually require further adjustment.

1. Speed setting; an external adjustment used to set the speed at which the centrifugal governor will control.

2. Speed droop; an internal adjustment used to permit parallel operation of units controlled by the centrifugal governor.

3. Needle valve; an external adjustment used to stabilize the centrifugal governor.

The actuator section of the EG-132P has no external operating adjustments.

The actuator uses oil from the engine lubricating system or from a separate sump (not furnished by Woodward Governor Company). It does not have a self-contained sump.

EG-B2P governor/actuators are available with the terminal shaft extending from either or both sides of the case. They can be furnished with the speed adjusting shaft (for the centrifugal governor section) extending on either side. However, most units use a speed adjusting screw in the top cover and omit the speed adjusting shaft entirely.

DIRECT AND REVERSE ACTING TYPES

EG-132P actuators are available in either the direct or the reverse acting type.

The direct acting actuator operates with electronic controls which produce an increasing positive voltage to the actuator as fuel increase is required.

Cover pin No. 1 is positive and cover pin No. 2 is negative see figure 5-28. The terminal shaft of the direct acting actuator goes to shutdown on loss of control voltage and thus provides a failsafe feature. However, ballhead governing control will

NOTE:

EITHER OIL SUPPLY HOLE

MAY BE USED. OPTIONAL

SIZE. .250 - 11 N.P.T.F.

CUSTOMER DRIVE

MUST NOT PUSH

DRIVE COUPLING 10

LESS THAN THIS

DIMENSION

- 36 SAE SERRATION

PLAIN AS SHOWN.3T3 - 3?4 TERMINAL

SHAFT - MAY BE

LOCATED ON-

EITHER OR

BOTH SIDES OF CASE

(Do Not Use For Construction)

Figure 1-2. Outline Drawing EG-132P Governor/Actuator

37?00-C.32 not start on its own, operator intervention is needed, (see Auxiliary Devices, Section 6).

The reverse acting actuator operates with electronic controls which produce a decreasing positive voltage to the actuator as a fuel increase is required. (See Manual 82542, 2301 Reverse Acting Systems.) Cover pin No. 1 is negative and cover pin No.,2 is positive, see figure 5-28. The terminal shaft of the reverse acting actuator goes to maximum fuel on loss of control voltage. The transfer from electrical actuator operation to� ballhead governor operation takes place on its own. This is not meant to imply that an automatic operational transfer will take place, i.e., same speed setting, same load sharing capability. (See A.N. 50507 for more information).

NOTE

To change a direct acting actuator to a reverse acting actuator or vice-versa, the actuator calibration must be changed as well as the polarity.

SPEED DROOP

Speed droop is adjustable (internally) between zero and twelve percent. Maximum amount of droop is reduced if terminal shaft travel is shortened ' Speed droop permits load division between two or more engines driving generators operating in parallel or driving a common load on a single shaft. If the engine is operated alone the governor may be set for zero droop (isochronous operation).

Parallel engine-generator units should have droop set sufficiently high to prevent the units from interchanging load. If one unit in the plant or system has enough capacity, its governor may be set on zero droop to provide isochronous operation. By maintaining constant speed, this unit regulates the frequency of the entire system.

Isochronous operation permits this unit to absorb all load changes within the limits of its capacity and also control frequency if its capacity is not exceeded.

The system frequency is adjusted by changing the speed setting of the governor operating isochronously. Load distribution between units is accomplished by changing the speed setting of the governors) having speed droop, EXTERNAL SHUTDOWN SOLENOID

Since no governor mounted shutdown device is available for this small actuator/governor, it is common practice to apply an external solenoid for shutdown. The solenoid allows the governor control oil to drain to the prime mover oil sump and thus create a shutdown.

Two factors are of primary importance in utilizing external solenoid shutdowns. First is the location of the solenoid. Figure 1-3 following shows the proper connection. Once a suitable connection is decided, the solenoid must be connected with tubing runs as short as possible. The solenoid must also be mounted below the governor and oriented so that it does not fill with air. Air trapped by the tubing causes governor instability.

The second consideration is solenoid size. The solenoid and all connected tubing must pass enough flow to ensure that the governor moves to minimum position and remains there. Shutdown of the EG-B2P Governor/Actuator is accomplished by draining oil from the increase fuel side of the compensating land on the actuator pilot valve.

This forces the pilot valve to drain control oil to move the power piston to minimum fuel. Since this is a restricted flow, the solenoid for the EG-B2P must flow .6 GPM with a maximum pressure drop of 10 PSI. Therefore, different flow capabilities are required depending on rated governor speed.

1.-

9�A

AUELI I

RETURN

To SUMP �

SHUTDOWN

ECTION

PTF

THIS PART OF THE DRAIN LINE MUST BE AT LEAST AS

HIGH AS THE OUTLET ON THE GOVERNOR/ACTUATOR.

USE AT LEAST 3/8 IN. O.D. TUBING

82500-A-349

Figure 1-3. Solenoid Shutdown Connection

Y

SPECIFICATIONS

Table 1-1. Specifications

CONTROL CHARACTERISTICS

Governor

Steady State Speed Band:OUTPUT + .25% of rated speed.

Terminal Shaft: .375"-36 SAE serrations, plain or keyway, either side or both sides of case.

Droop: Can be set from 0% to 12% over full output travel.

Internal adjustment.

Liseful Work Capacity:

Maximum Work Capacity:

Stalled Torque Rating:

Terminal Shaft Angular Travel:

Ballhead Assemblies:1.5 ft-lb at 350 psi Solid or spring driven vibration damping type.

Available in undamped natural frequencies of:

0, 1.7, 3.0, 4.8, 6.7 or 9,2 Hz (cycles per second)

O' F to 200' F (with proper viscosity oil).

2.5 ft-Ib at 350 psi.

4.5 lb-ft at 350 psi.

Operating Temperature:

32"

Calibration: I to 2 degrees from minimum shaft position at 20 mA.

30 to 31 degrees travel from minimum shaft position at 160 mA.

Recommended utilization angle of 210 for full load to no load. Relation between engine torque output and terminal shaft travel should be approximately linear.

Actuator

Time Constant:

(Shaft Driven)

Hysteresis:

Linearity:

0.10 sec. (nominal) at 350 psi operating pressure.

Within 3%.

Within 0.5%.

Linkage:

PILOT VALVEGOVERNOR DRIVE

Shaft: .562"-6 spline. Plunger Movement:

Speed Range:

Recommended Operating Speed Range:

Typical Power

Rotation:

1200 to 4000 rpm.

2400 to 3600 rpm.

1/3 hp to turn drive shaft at normal operating speed and temperature.

CW or CCW.

Actuator:

Governor:

Balanced between transducer coil force and restoring spring force.

Balanced between ballhead centrifugal force and speeder spring force.

Bushing Rotation: Mechanically driven by prime mover as an integral part of governor drive shaft.

0015WAAn

TRANSDUCER COIL Supply Pressure: Maximum 50 psi.

Minimum 10 inch H20 suctiol

330 psi. to 375 psi. (325 psi plus inlet pressure).

20-25 micron for 2 gpm.

Coil Resistance: 30 to 35 ohms at 680 F.

Operating Pressure:

Filter:

Max. Allowable Current:

400 mA.

200 rnA during normal operation. 400 mA during centering operation.

Nominal Input Current Range:

Viscosity: 50 to 200 SSU is recom-ended.20 to 160 rhA.

Mating Plug: MS-3106A 12S-3S Flow: Peak demand of 2 gpm during transients: steady state flow

0.60 gpm (nominal) at 350 psi

60 SSU.HYDRAULIC SYSTEM

Supply Oil: Mineral oil. Some synthetic oils are acceptable. If doubt exists about compatibility of fluid with actuator com-ponents, contact Woodward Governor Company.

Engine lubricating system or a separate sump.

3/8 inch minimum.Piping:

REFERENCES

Sales, Service and additional Product Information are available through the offices listed on the back cover of this manual.

TITLE

Shutdown Methods for EG-132P and EG-B2C Governor/Actuator, and SG and PSG Governors.

Source:

ITEM

Application Note

NUMBER

50504

Application Note

Manual

50507

82542

Electro-Hydraulic Backup Governor for Generator Sets

2301 Reverse Acting Systems.

I kWARNING

This section provides information for installation, such as drive requirements and external connections. Oil supply and supply line connections conclude this section.

INSTALLATION

Using a gasket between the base of the unit and the mounting pad, mount the governor/actuator unit on the mounting pad. Square the unit with the engine linkage and in line with the drive. Fit the splined drive shaft into the drive with a free, slip fit; no tightness is permitted, The unit must fit the mounting pad of its own weight without any force being applied. Also, make allowance for unrestricted oil flow drainage through the drive shaft bore and annulus within the base mounting pilot.

Design and adjust the fuel linkage to use approximately 21" of the terminal shaft travel from no-load to full-load. Divide the unused terminal shaft travel equally on each side of the 21' range.

The engine linkage must not bind and backlash must be minimal, If there is a collapsible member in the linkage, it must not yield when unit moves the linkage rapidly, NOTE

It the installation must be changed from vertical to horizontal, or vice versa, a plug must be added or removed, and a new calibration is needed. Return the unit to Woodward Governor Company for calibration.

LINKAGE ADJUSTMENT

Maximum and minimum lines on the terminal shaft dial plate (136 on figure 7-1) indicate the limits of terminal shaft travel during normal operation (approximately 32'). The pointer (138) is pre-set at the factory and should not be moved, Do not use the physical minimum stop of governor terminal shaft to align fuel linkage since this position will not be reached when operating. Instead, set the linkage so the prime mover's fuel control Is at Its minimum fuel position when the EG-13213 pointer Is just above the minimum fuel mark on the dial.

GOVERNOR/ACTUATOR DRIVE

Drive the actuator's flyweight head directly from the engine. For best results, operate the unit in the range of 2600 to 4000 rpm at normal operating speed. One-third horsepower is required to drive it at 3600 rpm at normal operating conditions.

A smooth drive is important to prevent false speed change signals to the governor flyweights.

Attempting to correct for these changes, results in a continual vibration of the actuator terminal shaft and engine fuel linkage.

Normally, drive shaft rotation can be in either direction without making any changes in the unit.

Check for correct direction of rotation before actually driving the unit.

OIL SUPPLY

Connect a 3/8 inch O.D. tubing oil line from the oil supply to either of the two 1/8 inch pipe tapped inlet holes of the unit. A minimum of 5 psi oil pressure is required at the unit end of the line. It a separate sump is used (rather than engine lubricating oil), the distance the governor must lift the oil should not exceed 12 inches and a foot valve with a capacity of 2 gallons per minute must be used.

Notice that the EG-1321? has excess travel in the decrease fuel direction when the prime mover is not running.

When oil from the engine lube system is used, install- a 2 gpm - 20-25 micron filter in the oil supply line.

SECTION 2

INSTALLATION PROCEDURES

IINTRODUCTION

The prime mover should be equipped with a separate overspeed (overtemper-ature, or 'overpressure, where applicable) shutdown device(s), to protect against runaway or damage to the prime mover with possible personal Injury or loss of life should the mechanical-hydraulic governor(s), or electric control(s), the actuators), fuel control(s), the driving mechanisms), the linkage(s), or the controlled device(s) fail.

WARNINGhWARNING

When first starting the prime mover be prepared to Initiate an emergency shutdown In the event of a valve, linkage, prime mover or governor failure.

ACTUATOR CONTROL

During normal operation the actuator is controlling. At this time the centrifugal governor power piston is at the top of its stroke (for reasons to be discussed later).

The actuators' pilot valve plunger controls the flow of oil to and from its power piston. The pilot valve plunger is connected to an armature magnet which is spring-suspended in the field of a two-coil polarized solenoid. The output signal from the electric control is applied to the polarized coil, and produces a force, proportional to the current in the coil. Position of the actuator shaft is proportional to the electric input signal to the actuator.

When the unit is running under steady state conditions, the compression spring force, the restoring spring force and magnetic forces always balance, and the pilot valve plunger is "centered".

The control land of the plunger covers the control port in the pilot valve bushing and no oil flows to or from the power piston.

If the signal from the electric control decreases (due to an increase in engine or turbine speed or a decrease in unit speed setting), the compression spring force, now relatively greater, raises the pilot valve plunger. Oil under the actuator power piston drains to sump. The oil pressure constantly applied to the upper side of the loading piston and power piston now forces the pistons down as the floating lever pivots about its connection to the centrifugal governor power piston. The loading piston rotates the terminal shaft in the "decrease fuel" (or steam) direction as it moves down.

As the actuator power piston moves down, it lowers the left end of the first restoring lever. The clamping plate, attached to the first restoring lever, pushes down on the second restoring lever.

The loading on the restoring spring is thereby increased. The loading piston and actuator power piston move down until the increase in restoring spring force is sufficient to offset the increased force resulting from the increased electric signal.

When the pilot valve plunger is pushed back to its

SECTION 3

PRINCIPLES OF OPERATION

INTRODUCTION

This section provides information concerning the functional operation of the EG-132P. The schematic arrangement of the EG-132P is shown in figure 3-1 with parts in relative positions assumed during normal operation. Oil enters the unit through either of the two inlet holes in the side of the base. The oil passes from the suction to the pressure side of the pump. After filling the oil passages, the pump builds up the oil pressure.

When the pressure is great enough to overcome the relief valve spring force and push the relief valve plunger back to uncover the bypass hole, the oil recirculates through the pump.

Rotation of the pump in the opposite direction from that shown in figure 3-1, closes the open check valves and opens the closed check valves.

The loading piston positions the terminal shaft.

Constant oil pressure is applied to the upperside of the loading piston always tending to move it in the "decrease fuel" direction, Either the governor power piston or the actuator power piston can move the loading piston in the "increase fuel" direction since the effective area on which the control oil pressure acts is greater on the power piston than on the loading piston, In the event of an electric failure, the unit goes to minimum fuel. If the actuator goes to minimum fuel, apply a 9 volt dc supply to the transducer to take the actuator toward maximum fuel. This allows the governor to take control. Adjust the speed adjustment screw to give the desired steady-state speed.

NOTE

If the unit has the manual override knob on the cover (see section 6), push it down and turn it to the right to lock out the actuator control.

FIRST RESTORING LEVER\", LINKAGE RA

SPEED DROOP BRACKET

(MOVE -TO ADJUSTABLE PIN

INCREASE DROOP) LOCK SCREW

SPEED SECONDSPEED ADJUSTING SPEED DROOP RESTORING

ADJUSTMENT SCREW LEVER PIVOT LEVER

LEVER GOVER ARMPo

PIVOTPIN I OWER"�,� (FIXED PIVOT) TERMINAL elI ISTON

SHAFT

SPEEDER

SPRING COMPRESSIONSPRING

FLOATING LEVER

FLYWEIGHT ARMATURCOMPENSATION DIN MAGN

NEEDLE VALVE PISTON DEC, INC.

COMPENSATION

LAND

PILOT VALVE

PLUNGER

PILOT VALVE

BUSHING ACTUATORPOWER

CONTROL PISTON

LAND

BYPASS BUFFER

TO SUMP PISTON PORTING SPRING (2)

PUMP

GEARS

TO 'lump

RELIEF VALVE

PLUNGER

CLOSED RELIEF VALVE

CHECK SPRING

VALVE

OPEN

CHECK

INCOMING VALVE

OIL SUPPLY

CENTRIFUGAL ELECTRIC

GOVERNOR SECTION ACTUATOR SECTION

TRAPPED OIL AND

GOVERNOR PUMP SUMP OIL PRESSURE GOVERNOR POWER ENGINE OIL PRESSUREM OIL PRESSURE CYLINDER OIL PRESS.

TIO ADJUSTMENT

82NO-8-70

Figure 3-1. Schematic Diagram EG-B2P Governor/Actuator

. 00DWARD

centered position, movement of the power piston, loading piston, and terminal shaft stop.

If the signal from the electric control increases, (due to a decrease in engine or turbine speed or an Increase in unit speed setting), it creates similar movements in the opposite directions. The pilot valve plunger lowers, allowing pressure oil to flow to the underside of the power piston and push the piston up. The loading piston raises, rotating the terminal shaft in the "increase ' fuel" (or steam) direction. At the same time, the upward movement of the power piston acting through the restoring levers, decreases the restoring spring force, recenters the pilot valve plunger, and stops movement of the terminal shaft.

GOVERNOR CONTROL

The governor pilot valve plunger controls the flow of oil to its power piston. If the plunger is centered, no oil flows through the pilot valve and the power piston is stationary. The greater of two opposing forces moves the pilot valve plunger: the speeder spring force tends to push it down, the centrifugal force developed by the rotating flyweight is translated into an upward force which attempts to raise the plunger. With the pilot valve centered, there is one speed at which the centrifugal force of the flyweights is equal and opposite to the speeder spring force.

With the speed setting of the governor set slightly higher than the actuator, the centrifugal force of the rotating flyweights is not sufficient to lift the pilot valve plunger to its centered position.

Consequently, with the actuator controlling, pressure oil is continually directed to the underside of the governor power piston to hold it up against its stop. It is for this -reason that the power piston of the governor is up against its stop when the actuator is controlling.

With the unit running on-speed with the governor controlling, the pilot valve plunger is centered. It a load is added to the engine, the engine and governor speeds decrease. The pilot valve plunger is lowered by the speeder spring force which is now greater than the centrifugal force of the flyweights. Pressure oil flows to the buffer piston and moves it towards the power piston, The oil displaced by the buffer piston forces the power piston upward, the loading piston is raised, and the terminal shaft rotated in the direction to provide the additional fuel needed for the new load.

The movement of the buffer piston towards the power piston partially relieves the compression of the left hand buffer spring and increases the compression of the right hand buffer spring. The force of the right hand buffer spring tending to resist this movement results in a slightly higher oil pressure on the left of the buffer piston than on the right. The pressure on the left of the buffer piston is transmitted to the underside of the compensation land of the pilot valve plunger; the pressure on the right of the buffer piston is fed to the upper side of the compensation land. The difference in pressures on the two sides of the compensation land produces a force which acts to push the pilot valve plunger back to its centered position.

When the terminal shaft has rotated far enough to satisfy the new fuel requirement, the pilot valve recenters. This is due to the differential force on the compensation land plus the centrifugal force of the rotating flyweights, even though the engine speed has not returned completely to normal.

Power piston and terminal shaft movement stops.

The continued increase of speed to normal increases the centrifugal force developed by the rotating flyweights. However, this increase of speed to normal does not cause the flyweights to lift the pilot valve plunger above center. Oil leakage through the needle valve orifice equalizes the pressure above and below the compensation land at a rate proportional to the return of the engine speed to normal. Consequently. as the centrifugal force increases, the compensating force decreases.

With the pressures above and below the compensation land equalized, the buffer springs return the buffer piston to its normal, centered position.

When engine load decreases, the resultant increase in governor speed causes the flyweights to move outward and raise the pilot valve plunger.

With the pilot valve plunger raised, the area to the left of the buffer piston is connected to sump. The loading piston, which is continually urged downward by oil pressure from the governor pump, moves down and forces the governor power piston down. The movement reduces the fuel to meet the new requirement. Again, differential pressure across the compensation land assists in recentering the pilot valve plunger.

By-pass ports are provided in the buffer cylinder to facilitate large corrective movements of the power piston. A large increase or decrease in the speed setting of the governor, or a large increase or decrease of load on the engine, will require a correspondingly large movement of the power piston to make the necessary correction to the fuel setting. Under such conditions, the buffer

I 1 piston will move only far enough to the left or right to effect an opening at the bypass port (pressure or drain). Oil will then flow directly to or from the power cylinder through the bypass port without further increasing the differential oil pressure force existing on the compensating land.

The speed at which the governor controls the engine is determined by the loading or compression of the speeder spring which opposes the centrifugal force of the flyweights. The standard EG-132P has a speed adjusting screw in the top cover as shown in figure 3-1.

SPEED DROOP

Speed droop is used in governors to divide and balance load between engines or turbines driving the same common load or driving generators paralleled in an electrical system.

Speed droop is defined as the decrease in speed taking place when the governor output shaft moves from the minimum to the maximum position in response to a load increase. It is expressed as a percentage of rated speed. If instead of a decrease in speed, an increase takes place, the governor is showing a negative droop.

Negative droop can cause instability in governor operation.

Not enough or too much droop can also cause faulty governor operation. Not enough droop can cause instability in the form of hunting, surging or difficulty in load sharing. Too much droop can result in large speed undershoots and overshoots upon speed setting or load changes. It can also at times result in an output shaft jiggle on some types of governors.

Using an example where governor speed is 1500 rpm at no load and 1450 rpm at full load, droop can be calculated with the formula:

Droop No load speed - Speed at Full load No load Speed

1500 rpm - 1450 rpm 1500 rpm

50 33 = 3.3% of No load Speed 1500 100

If the decrease in speed is greater than 50 rpm, droop greater than 3.3% is shown by the governor. If the decrease in speed is less than 50 rpm, droop less than 3.3% is shown by the governor.

Remember that the amount of speed droop depends also upon how much governor terminal shaft or tail rod travel is used. As a result, the maximum droop that can be obtained depends also on the adjustment of the fuel linkage between the governor and the prime mover, as this adjustment determines how much output shaft travel is used between no load and full load.

Speed droop is provided in the EG-132P through linkage which varies the loading on the speeder spring as a function of the power piston position.

The change in speeder spring force for a given movement of the power piston is determined by the position of the adjustable pin in the linkage between the power piston and speeder spring. If the pin is on the same centerline as the speed droop lever pivot are, there is no change in speeder spring force as the power piston moves and the governor operates as an isochronous (constant speed) control. The further the adjustable pin is moved away from the pivot arm centerline, the greater is the change in compression of the speeder spring for a given power piston movement.

With the unit operating under the electric control, the speed droop feature is, in effect, inoperative.

During such operation, the governor power piston remains in the maximum position for all engine or turbine loads (except possibly momentarily during transients). Therefore, the speed droop linkage does not alter the speeder spring compression when the actuator is controlling.

In a conventional droop linkage arrangement, droop is thought of as a decrease in speed with an increase in load (expressed as a percentage of rated speed).

However in the EG-132P droop linkage arrangement, full droop effect can take place without an increase in load. It can take full effect for example, when the actuator is going from ballhead control to electric control because the ballhead power piston moves to the Maximum up position. This gives maximum droop effect which lowers the mechanical speed set point, to a point which can be lower than the electrical speed setting.

For this reason interference between the mechanical and electrical governors can occur. To eliminate interference, droop can be reduced to zero, or the speed difference between the two governors can be increased by setting the governor ballhead speed 3 to 5% higher than the electrical actuator speed.

This eliminates interference between the two governors and allows the electrical actuator to control.

1 2

4. Remove cover and use adapter plate shown in figure 4-1. to hold speed adjustment screw.

5. Insert a 7/64 inch Allen wrench through the hollow center of the adjustable spring seat (90), and engage the centering screw (97).

Turn the centering screw cw until it bottoms GENTLY. Back it off two and a halt turns to establish an initial starting position.

825?0.148

NUT 925?0-141

SCREW

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PLUG LQ

PART

NUMBER

NAME

825WA4M

8909-032 8909-038 8959-028 8959-031 370109 8995-054 8995-005

Test Stand Centering Box Electronic Counter Magnetic Pickup Pilot Valve Wrench Ballhead Cover Removal Tool Ballhead Assembly Tool

Figure 4-1. Speed Setting Adapter Plate

6. Make sure to align the pointer with the maximum position on the dial plate by rotating the terminal shaft in the full increase fuel direction. (Both ballhead & electric power pistons in full up position, i.e., the ballhead governor underspeeded and the electric actuator pilot valve below center.)

NOTE

This is important since the unit will either not control or become unstable below minimum. Checking the dial plate and pointer position insures that the unit is operating in its correct range.

3. Check pump pressure. It must be 350 psi plus supply oil pressure.

7. Check governor section for leaks. hunting, drifting and oil pressure.

. OODWAQL)

SECTION 4

ADJUSTMENTS

INTRODUCTION

This section includes procedures for making adjustments normally made at the factory for each particular unit and they are only required after it is repaired or overhauled. These adjustments are preferably made with the unit on a test stand.

NOTE

Item numbers shown in parenthesis indicate parts as shown in the exploded view figure 7-1.

RECOMMENDED TOOLS

These tools and the equipment listed may be purchased from Woodward Governor Company.

Table 4-1. Recommended Tools

PRELIMINARY ADJUSTMENTS

I . Mount unit on test �tand and connect oil inlet, pump pressure and drain connections.

A minimum oil pressure of 5 psi at a temperature of 140 to 150OF is required.

Connect the governor terminal shaft to the test stand speed control link.

2. Drive the unit in the normal direction of rotation.

the amount of droop percentage. If the speed droop needs to be increased, move the droop bracket towards the flyweights. Move the droop bracket away from the flyweights to decrease droop.

4. Repeat steps 2 and 3 above until the correct droop is obtained. Remember that Maximum speed adjustment must be reset each time droop is readjusted.

CENTERING PILOT VALVE PLUNGER

1. Adjust speed adjusting screw on the adapter plate until governor is at least 5 to 6% above steady-state speed. This eleminates interference between the two governors and allows the electric actuator to control.

2. Disconnect test stand linkage from terminal shaft and install a protractor to read the terminal shaft position between minimum and maximum.

3. Back out actuator pilot valve centering screw

(97) 2 and a half turns after bottoming very carefully against spring. Use a 7/64 MW Allen wrench. R efer to preliminary adjustments, step 5.

2 OHM 10 W CASE PLUG CONNECTOR--,,

ETER (SEE FIG. 5-28 __r

SPEED DROOP ADJUSTMENT

Speed droop is adjustable internally. The speed droop bracket (116 on figure 7-1) is clamped to the speed droop lever with a set screw. A pin on the droop bracket carries the floating lever (120).

When this pin is aligned with the droop lever shaft the droop will be zero. Speed droop is normally set in the range of 3 to 4%.

If speed droop setting needs to be changed, use the following procedure:

1. Adjust the unit's speed using the speed adjustment screw until the desired rated speed is obtained.

2. Simulate an underspeed condition until the, terminal shaft travels to a position just short (111 to 20) of maximum line on the dial plate.

For greater accuracy, cutout the protractor printed on the inside back cover of this manual, following the protractor outline.

Fasten the protractor to the EG-B2P and attach a wire pointer to the output shaft.

I-WITCH

NORMAL

OFF

CENTER

a

62500-A-85

Figure 4-2. Actuator Test Circuit

4. Set test circuit (figure 4-2) to OFF and connect to transducer plug on actuator case.

5. Connect a 9 volt dc power source to test circuit. Set test circuit to CENTER.

6. Adjust test circuit potentiometer to 400 Ma then set switch to OFF.

7. Adjust spring seat screw (90) with a 1/8 inch Allen wrench until terminal shaft rotates approximately to its mid-point of travel. Turn

Readjust the speed setting screw if necessary to obtain terminal shaft position at the required speed.

3. Simulate an overspeed condition until the terminal shaft travels to a position just short (10 to 20) of the minimum line on the dial plate. At this point the speed should rise by

OODWAR13

GOVERNOR NEEDLE VALVE SETTING

Surge the unit by setting speed droop to zero and opening the needle valve. It is important to set speed droop to zero, as the stabilizing effect of speed droop may not allow the governor to hunt.

Zero speed droop is set when the pin on the bracket (116 figure 7-1) is on the center line with the shaft hole in the droop lever (112).

After 1 minute, gradually close the needle valve

(18) 1/4 to 1/2 turn from bottoming until the speed just settles out. Closing the needle valve further than necessary makes the unit slow to return to set speed after a load change. Never close the needle valve tight. Test the unit by manually disturbing the speed. Only a small overshoot or undershoot should occur before the unit returns to its steady-state speed.

The electric actuator section has no needle valve adjustment.

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seat (90) cw to move terminal shaft towards maximum fuel and ccw to move it towards minimum fuel.

8. Set test circuit to CENTER. Observe and note direction and position of terminal shaft movement.

A. If terminal shaft moves to another position set test circuit to OFF.

1 . For movement towards increase fuel turn pilot valve centering screw (97) slightly cw.

2. For a movement towards decrease fuel turn screw (97) slightly ccw.

3. Note the new position for reference in case more adjustment is needed.

4. Repeat steps 8.A.1. and 3. or 8.A.2 and 3. until no movement of the terminal shaft occurs when the test circuit is moved from OFF to CENTER. Continue on to step 9 and calibrate terminal shaft.

B. If terminal shaft did not move from its original position, the pilot valve plunger is centered. Continue on to step 9 and calibrate terminal shaft.

9. Turn test circuit to OFF and set potentiometer to zero mA.

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Do not exceed 200 mA during remainder of test to prevent damage to the magnetic properties of the magnet.

10. Set test circuit switch to NORMAL.

11. Adjust potentiometer to 20 mA or to Min value signal (see Specification sheet for

EG-B2P).

12. Turn spring seat (90) ccw until actuator terminal shaft moves to minimum position on dial. Turn seat (90) cw until shaft moves 1 to 20 toward maximum.

13, Adjust potentiometer for 160 mA or to Max.

value signal (see Specification sheet for EG-B2P), Terminal shaft movement should be an additional 29 (±1/2)0 towards maximum.

14. If adjustment is necessary, loosen screws

(105) slightly and turn eccentric pin (95) in restoring ]ever (93) as required to shift position of ratio adjustment clamping plate (102).

Move ratio adjustment plate (102) towards piston link (78) to decrease terminal shaft travel and away from piston link (78) to increase shaft travel.

15. Repeat maximum and minimum mA adjustments until terminal shaft travels correct distance and steps 12, 13 and 14 are satisfied.

16. Shut off test stand. Disconnect test circuit.

Remove speed setting adapter plate and replace it with cover. Be sure speed setting screws protrude the same distance belo edge of case, or that the governor's speed is sufficiently high to prevent interference with actuator portion.

SPEED ADJUSTMENT

The speed adjustment can be done on the test stand or with the unit installed on the engine. It must be done with the unit's cover installed and fastened to the unit.

GENERAL INFORMATION

Three arrangements for setting the speed of the governor (centrifugal ballhead) section of the unit are available.

1. A single speed adjustment screw.

2. A combination of high and low speed stop set screws and a speed adjusting shaft.

3. An electric motor and high speed stop set screw.

As seen in the schematic diagram, figure 3-1, a speed adjustment changes the speeder spring force. The balance point of the opposing speeder spring force to the centrifugal force of the flyweights determines the speed setting.

1. Figure 3-1, shows the speed adjustment screw. Turn the adjustment screw cw to increase the speed and ccw to decrease speed.

2. Figure 7-1, the exploded view, shows the speed adjusting shaft (126), and the high (13) and low (149) speed stop screws. Set the

1 5

. 00DWAPrI

If droop is used, simulate an underspeed condition until the terminal shaft travels to a position just short (11 to 21) of maximum line on the dial plate. Readjust the speed setting screw if necessary to obtain terminal shaft position at the required speed.

If zero droop is used, maximum speed can be set at any terminal shaft position between maximum and minimum fuel positions.

Remember that maximum speed must be reset each time droop is readjusted.

ADJUSTMENTS AFTER TESTS

When actually operating, set the governor section at least 5 to 6% higher than the actuator section.

This normally allows the actuator to control without interference from the ballhead governor.

The greater the percentage of droop set in the ballhead governor, the higher the ballhead governor speed must be set to avoid interference between the two governors.

high to low speed range with the stop screws, Use the speed adjusting shaft to change speeds between these preset ranges. Speed may be changed remotely with the speed adjusting shaft and the proper connections.

3. Units equipped with an electric motor for speed adjustment may have a high speed stop screw. Adjust this screw to establish a high speed stop. The motor can then be used to control the speed setting remotely. This motor is a split field universal motor whicht drives the speed adjusting shaft through a worm and gear with a friction clutch to protect the motor if the adjustment is run against the stop.

SETTING MAXIMUM SPEED

Adjust the unit's speed using the speed adjustment screw, speed adjusting shaft or speed setting motor until the desired rated speed is obtained.

OODWARD

1 . Check the load to be sure that the speed changes observed are not the result of load changes beyond the capacity of the prime mover.

2. If the unit is controlling an engine, check the engine operation to be sure that all cylinders are firing properly and that the injectors are in good operating condition. If the unit is controlling a turbine, check the steam valves for proper operation.

3. Check the operating linkage between the unit and the prime mover to make certain there is no binding or lost motion.

4. Check for steam or fuel pressure changes.

5. Check the voltage regulator for proper operation, as applicable.

6. With the electric controls set for normal operation, check the voltage input to the unit.

(Refer to the applicable manual for troubleshooting the electric control unit.)

If neither load nor prime mover irregularities are found to be the cause of the speed variation. the cause may be either in the unit or in the drive from the prime mover.

The source of most troubles in any hydraulic actuator or governor stems from dirty oil. Grit and other impurities can be introduced into the governor with the oil, or form when the oil begins to breakdown (oxidize) or become sludgy. The internal moving parts are continually lubricated by the oil within the unit. Valves, pistons and plungers will stick and even "freeze" in their bores, due to excessive wear caused by grit and impurities in the oil. If this is the case erratic operation and poor response can often be corrected by flushing the unit with fuel oil or Kerosene, using the test circuit shown in figure 4-2 to cycle it. The use of commercial solvents is not recommended as they may damage seals or gaskets.

1 7

SECTION 5

MAINTENANCE

INTRODUCTION

This section includes information. for Troubleshooting, Disassembly, Parts check, Assembly, and Lubrication. In addition to the basic tools, the speed setting adapter plate (figure 4-1). the actuator test circuit (figure 4-2), and the pilot valve wrench (figure 5-1) will be necessary to disassemble, repair, and assemble the unit. See section 4 for a list of recommended tools.

Since these units vary somewhat depending on the individual requirements, one type of unit is used for disassembly and another type for assembly. Study the unit carefully during disassembly for ease in reassembly, The exploded view (figure 7-1) is referred to for disassembly, The unit used in figure 7-1 has a solid ballhead, speed adjusting shaft and high and low speed stop screws. The figures in this section, referred to for ass embly, are of a unit with a spring and oil damped ballhead, a low speed stop screw and stub speed adjustment shaft.

During reassembly replace all packings, gaskets, seals, retaining rings and cotter pins removed during disassembly, Cleanliness and careful handling of all parts is important, TROUBLESHOOTING

If trouble occurs in the governing system, the general location of the fault can be readily isolated to the actuator or to the electric control unit by connecting the test circuit shown in figure 4-2 to the actuator. Set the switch to NORMAL and operate the actuator by varying the position of the potentiometer. If operation of the actuator appears to be satisfactory, the trouble is in the electric control unit, Governor/Actuator faults are usually revealed in speed variations of the prime mover, but it does not necessarily follow that all such speed variations indicate Such faults. Therefore, when improper speed variations appear, the following procedure should be performed:

ION

Handle critical parts with extreme care.

Keep them separated so mating edges and surfaces are not'damaged. Sharp edges of plunger lands, piston grooves, metering ports, etc., must be maintained. Rounded edges, nicks or other damage to such edges will result In excessive Internal leakage and decreased control sensitivity.

DISASSEMBLY

Do not disassemble the unit or its various subassemblies any further than necessary.

1. Remove screws (153), cover (151) and gasket (150).

2. Remove pins (124) from speeder spring assembly, pin (121) from floating lever (120) and take out floating lever.

3. Remove pin (128) and tapered plug (129). Do not damage shaft bushing (125), or bore.

4. Drive speed adjusting shaft (126) toward opposite side of case to knock out the oil seal (130).

5. Remove speed adjusting shaft (126), speed adjusting lever (123), bushings (125) and spacer (1 27). Do not remove bushings (125) unless they need replaced.

6. Remove speed droop lever pin (131) 'connecting speed droop lever (112) and piston link (36).

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If the. speed variation of the unit is erratic but small, excessive backlash or a tight meshing of the gears driving the unit may be the cause. If the speed variation is erratic and large and cannot be corrected by adjustments, repair or replace the unit.

REMOVING THE EG-132P

1. Disconnect electrical plug on actuator, and' hydraulic tubing connections.

2. Before removing terminal shaft, mark both shaft and lever so they may be easily reinstalled at their original positions.

3. Remove the four stud nuts holding the governor to the mounting pad and lift the governor off. Remove the gasket between the governor/actuator and governor mounting pad.

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� CAUTION �

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Use care in handling and resting of the actuator/governor. Do not strike or rest the governor on its drive shaft as damage may result to drive shaft, oil seal, bearing, or internal parts or surfaces. Set the actuator/governor on wooden blocks to protect the drive shaft.

7. Remove retaining rings (139) and both dial plates (136 and 140) from the case.

8. Remove retaining ring (115), pull out pivot pin (114) and take out speed droop lever (112).

NOTE

If the speed droop bracket is removed, mark its position on the speed droop lever for ease in reassembly.

4. Do not remove or disturb the position of screws, levers, etc., which function as adjustments; nor disassemble the various linkages further than required to effect removal unless replacement is necessary.

5. Do not remove press-fit parts such as bearings, locating (dowel) pins, oil pump, check…