Attachment_7__Control_Gates_Operation_and_Maintenance_Manual.pdf

Moose Creek Dam Chena Lakes Projects Fairbanks, Alaska

JANUARY 1990

CONTROL GATES

OPERATION AND MAINTE: :,*.I :CE

MANUAL

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CHENA RIVER LAKES PROJECT

FAIRBANKS, ALASKA

CONTROL GATES

OPERATION MAINTENANCE MANUAL

J a n u a r y , 1990

Prepared f o r :

U.S. Army Engineer D i s t r i c t Corps of Eng inee rs

Alaska D i s t r i c t Anchorage, Alaska

Prepared by:

U.S. Army ~ n g i n e e r D i v i s i o n Corps of Eng inee rs

H y d r o e l e c t r i c Design Cen te r P o r t l a n d , Oregon

TABLE OF CONTENTS

PART 1 - OPERATION

1. Description of system

1.1 Power unit

Page

1.2 Control panels 6

1.3 Cylinders 10

1.4 Gate position indicators 10

2. Operating Procedure 11

2.1 Gate Raising 11

2.2 Gate Lowering 13

2.2.1 Normal Lowering 13

2.2.2 Emergency Lowering (without power) 15

2.2.3 Forcing the gate down 16

PART I1 - MAINTENANCE

3. Gate removal

4. Gate installation

5. Installation of emergency gate

6. Cylinder and rotating parts assembly maintenance 22

7. Power unit maintenance

8. Control panels maintenance

9. Electrical equipment maintenance 46

PART I11 - APPENDIX

10. Drawings

M-6 New Equipment Arrangement M-7 Schematic Diagram Fluid Power System M-8 Power Unit Sheet 1 M-9 Power Unit Sheet 2

Control Panel Gallery Piping Sheet 1 Gallery Piping Sheet 2 Support Beam and Cylinder Piping Sheet 1 Support Beam and Cylinder Piping Sheet 2 Supports Hoist Cylinder Details Support Beam Sheet 1 Support Beam Sheet 2 Support Beam Sheet 3 Gate Wheel Lubrication Piping Modification to Existing Gate Position Indicator Support Beam and Cylinder Assembly Procedure Sup. Bm., Hoist Cyl. and Gate Installation Procedure Sup. Bm., Hoist Cyl. and Gate Removal Procedure Sling Assembly

New Electrical Equipment FCQl One Line & Equipment Control Diagrams

Elevations and Sections Operating Gates Elevations and Sections Spare Gate Elevations and Sections Bulkhead

11. Parts Manufacturers and Suppliers

12. Index

Page

PART I - OPERATION

1. DESCRIPTION SYSTEM

The hydraulic gate hoists will raise and lower the four flood control gates under normal conditions up to El. 515 pool.

For floods between El. 515 and El. 523, the system is capable of lowering the gates to a regulating position but not raising them.

Floods of this magnitude are considered to be of extremely unusual magnitude.

If all electrical power is lost, the gates can be lowered but not raised.

If conditions arise which require the gates to be forced down, the hydraulic system can be readily set up to accomplish this.

When the gates have been adjusted to a desired flood regulating position, they can be left unattended and maintain that position with minimal change over a period of several days.

To aid operators in determining gate position, a digital gate position indicator is used.

The system is controlled from within the flood control structure. See figure 1 and drawing M-6. No remote operation or monitoring is available.

The fluid power system schematic is shown on drawing M-7. Each of the four gate hoists uses two hoist cylinders. Operation of the hoists is initiated at a separate hydraulic control panel for each hoist. One power unit provides pressurized oil to operate the system.

POWER UNIT

Figure 3 shows the power unit. It consists of a reservoir, two variable volume pressure compensated pumps with 10 hp motors, relief valves, check valves, filters, low oil level switch, visual oil level indicator and thermometer and a tank heater with thermostat.

The power unit supplies the pressure needed to raise and lower the gates under normal conditions. The power unit will normally be shut off. It does not need to be turned on to support the gates in the fully raised or flood regulating positions. When a gate is to be raised or lowered, the power unit will be turned on at any one of the four control panels or at the power unit itself. When the power unit is turned on, the high pressure header will be pressurized to 3100 psi. The pressure compensated pumps will deliver zero volume until the operator uses one of the control panels to raise or lower a gate.

Pumps

Normally, the selector switch will be in the ttbothtt position, so both of the pumps in the power unit will run. If one of the pumps fails, it can be removed and serviced while the other is still operational.

The pressure compensator setting, 3100 psi, is the maximum pressure the pump can put out. At pressure below 3100 psi, the pump flow will be about 6.8 gpm. When the pressure approaches 3100 psi, the flow will decrease until it reaches 0 gpm at 3100 psi.

The flow of the pressure compensated pump is controlled by the compensator plunger varying the angle of the hanger (See Figure 3). If the hanger is perpendicular to the pump shaft, no flow will be delivered, i.e. the pump is ltcompensatingll. It is readily apparent that the pistons have zero stroke and therefore the pump can deliver no volume. Under these conditions, it takes essentially zero horsepower to turn the pump. If the angle of the hanger is increased, the stroke of the pistons and consequently, the pump flow increases. The position of the compensator plunger is controlled by the compensator, according to the discharge pressure of the pump. As the pressure approaches the compensator setting, the spool inside the compensator will shift allowing pump discharge pressure to be fed into the compensator plunger, this will change the angle of the hanger. When the full compensator setting has been reached, the hanger will be perpendicular to the shaft.

In case of failure or inadvertent high setting of the pressure compensator, pressure relief valves are included. They serve only as a backup to limit maximum pressure. The pressure relief valves are of the cartridge type and are contained in a manifold block along with a check valve. The check valves are to prevent reverse flow through the pumps.

Each pump has a case drain line to drain oil which leaks into the case during operation. If this case drain line is blocked during pump operation, the pump case will become pressurized and the pump will be destroyed.

Ball Valves

On each of the pump case drain and suction lines, there is a ball valve. These valves must remain open when the pumps are operated or the pumps will be destroyed. The valves may only be closed to take a pump down for servicing. The ball valve handles are equipped with screws to hold them in the open position. Any ball valve operation requires backing out the screws. This is to prevent any inadvertent closure of the valves.

Filters

The filters at the power unit provide 6 micron vvabsolutew filtration. Providing this degree of filtration will reduce wear and subsequent maintenance in this fluid power system. A high pressure filter is provided at the pump outlet. Two filters are provided at the low pressure return line. One filter removes particles while the other removes water, since water is destructive in fluid power systems. All of the filters have indicators which tell the operator if the elements need to be changed. If the red button is up, the element needs to be changed since the filter is approaching a condition in which all oil will be bypassed around the element. If the system is allowed to run under these conditions, contamination will increase. This will lead to increased maintenance and premature failure.

The low pressure filter and water absorbing filter have a reverse flow check valve which prevents backflushing of contamination if the gates are emergency lowered without power.

No pump inlet strainers are provided. They are not necessary provided that care is taken to prevent contamination from entering the reservoir during servicing. If large particles are introduced into the reservoir through carelessness, they could cause sudden catastrophic pump failure.

O i l H e a t e r

An oil heater is provided to keep the oil temperature at 70 F. It is not necessary or desirable to keep the heater on all year. It is only necessary to have the heater on when the gates need to be operated. Because of the size of the reservoir, it may take up to one day to bring the oil up to 70 F depending upon the ambient temperature. It is recommended that the oil be about 70 F before running the system because this creates better operating conditions for the pumps. The heater has a built in adjustable thermostat. There is a thermometer on the side of the reservoir for checking oil temperature.

During winter, it is recommended that the oil heater be shut off. In the spring, preferably at least a week before the system is to be operated, the heater should be turned on.

F l o a t Switch

A float switch in the reservoir is used to shut off the pumps if the oil level gets excessively low. A visual indicator is mounted on the side so the operator can check the fluid level.

The fluid level should be at its maximum when all of the cylinders are retracted. As the cylinders extend, the oil in the reservoir is drawn out to account for the volume of the rods.

1.2 CONTROL PANELS.

The control panels are shown in Figure 4. There are four control panels, one to operate each control gate. The control panel schematic is shown on drawing M-10 of the appendix.

Each control panel consists of two sandwich valve stacks on a standard DO2 manifold. The stack on the left is to control raising and lowering of the gate. The stack on the right is to operate the latch pin cylinders.

Directional Control Valve - Raise, Lower First, the operation of the valve stack for raising and lowering gates will be discussed. The directional control valve determines whether the gate goes up, down or is stationary.

This is the top valve in the stack. If the valve lever is pulled up, the gate will go up. If the lever is pulled down, the gate will go down. If the lever is centered, the gate will remain stationary. The directional valve is detented, so the lever will remain in a shifted position until the operator moves it again.

The valves are spool type, lever operated.

Counterbalance valve

The speed of the gate during lowering is controlled by the counterbalance valve, the valve which is second from the top. In order for the gate to be lowered, pilot pressure is required to open the counterbalance valve. The required pilot pressure is:

Pilot pressure = Relief setting - Load induced pressure Pilot Ratio

Pilot pressure is the pressure supplied by the pumps at port B of the valve stack. It is the pressure which is required to keep the counterbalance valve open.

Load induced pressure is the pressure on the high pressure side of the cylinder (rod end).

The relief setting is 2000 psi and is controlled by adjusting the screw on top of the valve cartridge. The relief setting is the maximum pressure the valve will hold.

The pilot ratio is 4.5. This is an internal feature of the valve which can not be adjusted.

From the above equation, it can be seen that the lower the load induced pressure, the higher the pilot pressure required to open the valve.

The pilot pressure can be read on the B-port gauge at each control panel. Load induced pressure is approximately equal to

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the pressure read on the A-port gauge.

The speed of the gate is limited by the pump flow. If the gate speed were to increase a small increment, the pumps could not supply the additional flow required and the pressure at the pilot port of the counterbalance valve would drop. This would cause the counterbalance valve to modulate slightly more closed, thus reducing speed back to the starting value. The counterbalance valve will ensure the gate moves at a constant speed which is related to the pump flow.

A-port relief valve

This relief valve is opened if emergency closure of the gate is needed and there is no electrical power available to run the pumps. To emergency lower the gate, rotate the knob of the valve counterclockwise. The gate speed will be limited by a flow control valve mounted at the bottom of each hoist cylinder.

B-port relief valves

The purpose of these valves is to limit the downward force which can be applied to the gate by the cylinder. Normal relief setting of this valve is 380 psi and at this setting no downward force can be applied to the gate. If downward force is required to get the gates to lower, the relief setting can be adjusted up to a maximum of 750 psi. See Section 1 - Paragraph 7. Operating Procedure. This setting corresponds to a downward force of 120,000 lbs. applied by the cylinders.

The setting can not exceed 750 psi because a second tamperproof B-port relief valve limits the maximum pressure.

Ball valve

The ball valve is located on the A-port. Its function is to prevent leakage of oil out of the high pressure side of the cylinder, through the A-port ball valve, which will cause the cylinder to drift. Whenever the gate is being held in a position to regulate flow through the spillway, this valve should be closed to minimize drift of the gates. If this valve is left open, the gates will drift at a significantly higher rate.

A-port pressure gauge

This gauge displays the pressure on the high pressure side (rod end) of the cylinder.

B-port pressure gauge

This gauge displays the pressure on the low pressure side (blind end) of the cylinder.

Latch cylinder directional control valve

This valve is used to extend or retract the latch pins.

Latch cylinder flow control valves

There are two valves which control the speed of the latch pins when they are extended or retracted. The valves are set such that the time to extend or retract the pins is about 2 seconds.

1.3 CYLINDERS

Hoist Cylinders

Each gate hoist uses two ten inch bore cylinders.(See Figures 5 and 18) The cylinders have synthetic piston seals which minimize drift. The cylinders are double acting so they can be used to raise the gates and if necessary, to force the gates down. Forcing of the gates down would only be used in an unanticipated scenario. In all reasonable circumstances, the gates will lower under gravity and the hydraulic (water) forces.

The hoist cylinders are a modified version of standard NFPA (National Fluid Power Association) cylinders. These cylinders had to have a modified design since they were too long to use tie rods.

Latch Cvlinders

These cylinders are 2 inch bore and 4 3/4 inch stroke. (See figure 18.1) They are standard NFPA cylinders. Each gate has 2 latch cylinders which are used to engage latch pins which hold the operating gates up and take the load off of the hoist cylinders.

Gate Position Indicators

The purpose of the indicator is to provide an accurate means of monitoring gate position for regulating water flow. There are two main parts, the rotating parts assembly on top of one hoist cylinder for each gate and the programmable position monitor in the electrical control cabinet.

Inside the rotating parts assembly, a cable is connected to the piston on one end and a drum on the other end. The drum is mounted on a spring wound shaft. As the piston moves, the shaft will rotate. An encoder (a digital device) is mounted on the shaft end. This device emits pulses in response to rotation. The encoder feeds this signal into the programmable position monitor. The programmable position monitor reads out the distance from the sill to the bottom of the gate, in inches.

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GATE EAR 7

OPERATING

2. OPERATING PROCEDURE

2.1 Gate Raising

1. Turn on the hydraulic pumps at control panel. (See figure 6 ) Open ball valve, red handle, on A-port (figure 4 ) .

2. Pull handle of directional valve 1CP up. (figure 4 )

3. When the gate is fully raised, pull handle of valve 6CP down to latch the gate. Leave the handle of valve 6CP down.

4 . Pull handle of valve 1CP down. This lowers the gate so it will rest on the latch pins.

5. Move the handle of valve 1CP to the center position.

6 . If not fully raising gate, skip step 3 and 4 . Move the handle of valve 1CP to the center position when desired gate position is reached. Close the ball valve, red handle, A-port.

7. Turn off the pumps.

Following is the detailed discussion of the raising steps.

1. Turn on the Dumps using the gate electrical control cabinet. The push-button station turns on both pumps. Either pump can be run alone, if desired,by using the selector switch located on the power unit control cabinet. When the pumps are on, they pressurize the high pressure header to 3100 psi.

2. ODen ball valve, red handle, A-~ort (Fiqure 4 ) . Move valve 1CP to the raise position. The gate now starts to raise. At the full open position, the piston reaches the end of its stroke, the gate stops moving, and the pressure quickly raises to 3100 psi.

If during raising, the pressure starts to rise significantly above normal, it indicates either trash is jamming the gate or the downstream side of the gate is dragging on the gate guides. Lower the gate part way and then try to raise it again. If it does not raise completely, determine by examination what the problem is. Watch the pressure and the gate position indicators to see if the pressure is rising gradually or suddenly. If the pressure rises gradually, then debris is probably not jamming the gate and the gate can be safely raised provided the pressure does not exceed about 2200 psi. If the pressure rises suddenly, debris is probably wedged and the gate can not be safely raised until the debris is dislodged.

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A record should be kept of the normal pressure required to raise a gate for each given pool. If this information is not available use the table below. Note that the pressure may vary by 100 psi or more due to change in piping pressure drop at different temperatures. These pressures are for a near fully closed gate. Pressure will increase slightly during the first 3 or 4 feet when the gate is raised up off the sill then gradually decrease to about 800 psi for a fully open gate.

Pool Elevation A-port Pressure (psi) (near fully closed gate)

At the completion of the gate raising with higher than normal pressure, the cause of the problem must be determined by inspection of the gate.

3. Move valve 6CP to the latch Dosition. Do this step only if the gate is to be fully raised. This moves the latch pins through the holes in the gate ears. One limit switch in each latch cylinder is used to sense if the latch pins are fully engaged. When fully engaged, a red light on the electrical control cabinet goes on. When not fully engaged, there is a green light.

4. Move valve 1CP to the lower position. Do this step only if the gate is to be fully raised. This sets the gate ears on the gate latch pins. If the gate continues to lower it means the latch pins have not fully engaged. Stop the gate lowering by moving valve 1CP back to the center position.

Move valve 1CP to the raise position and try again to extend the latch pins. If the pins do not move, the gate latch mechanism has to be checked out to determine the problem.

5. Move valve 1CP to the center Dosition. Once the gate is at the desired position.move the control lever on valve 1CP to the center position.

If the gate is to be left in an intermediate position, close the ball valve, red handle, A-port. The gate will hold at this position except some drift will occur due to leakage past the piston seals and ball valve. Drift should be on the order of 1" per day if the piston seals and ball valve are in good condition. Monitor the gate position indicator occasionally and correct gate position as necessary.

If the gate is fully raised, this step will prevent oil from flowing past the B-port relief valve when the pumps are on.

6. Turn off the pumps. Shut off the pumps at the gate electrical control cabinet or at the power unit. They are not needed to hold the gate in position. Running the pumps continuously will cause them to wear out prematurely.

2.2 Gate Lowering

Gate lowering consists of three separate conditions.

A . Normal Lowering. Normal lowering is when everything operates as designed.

B. Emersencv Lowerinq Emergency lowering occurs when power to the pumps is lost or some other condition has occurred that renders both pumps inoperative.

C. Forcinq the Gate Down. Forcing the gate down would occur if downward force from the cylinders is needed to close the gate This would be needed only during situations that the normal design capabilities can not handle, such as excessive gate wheel friction, unanticipated hydraulic forces, icing of the gate guides, dragging of the downstream side of the gate on the guides, or minor interference from debris.

Extreme caution must be exercised with this condition. If the gate is forced down due to sticking of the gate or binding due to trash significant damage may occur to the system. If the reason for the gate not lowering is higher than anticipated friction at high heads, forcing the gate down is an acceptable method to lower the gates and no damage will occur.

2.2.1 NORMAL LOWERING.

2.2.1.1 Lowering for fully raised, gate latched position.

1. Turn on pumps. (Figure 6)

2. Pull handle of valve 1CP up.(Figure 4)

3. Pull handle of valve 6CP down to unlatch the gate.

4. Pull handle of valve 1CP down to lower the gate.

5. When gate is at desired position shift handle of valve 1CP to the center position.

6. Leave handle of valve 6CP down (unlatch position).

7. Turn off pumps.

8. If gate stops prior to reaching desired location go to instructions for powered lowering.

7.2.1.2 Lowering from intermediate gate position.

Turn pumps. (Figure 6)

2. Pull handle of valve 1CP down to lower the gate.(Figure

3. When gate is at desired position shift handle of valve 1CP to the center position.

4. Turn off pumps.

5. If gate stops prior to reaching desired location go to instructions for forcing the gate down.

Following is a detailed description of the lowering steps.

1. Turn on the pumps using the gate electrical control cabinet. The push-button station turns on both pumps. Either pump can be run alone, if desired,by using the selector switch located on the power unit control cabinet. When the pumps are on, they pressurize the high pressure header to 3100 psi.

2. Move valve 1CP to the raise position. The gate now starts to raise. The gate raises a small amount to take the weight off the latch pins.

3. Unlatch the sate latch ins. Shift valve 6CP to the unlatch position. Leave valve 6CP in that position at the completion of the lowering operation.

4. Move valve 1CP to the lower position. The gate now starts to lower. For normal lowering the pumps need to be running to provided pilot pressure to open the counterbalance valve. The counterbalance valve is used to control the gate speed during lowering. If the flow through the counterbalance valve exceeds pump output, the pressure to the pilot valve in the counterbalance valve starts to drop which allows the counterbalance valve to modulate the flow and thus maintain a constant gate speed.

5. ----- Shift valve 1CP to the center position. Once the gate is at the desired position, move the control lever on valve 1CP to the center or hold position. The gate is held at this position except for valve and piston seal leakage. Monitor the gate position indicator to determine when it is necessary to raise the gate back to it's original position. Repeat steps 1,2,4,5 and 7 to do this.

6. For lowering from an intermediate position the same procedure is followed except that the gate is not on the latch pins and they do not have to be released.

2.2.2 EMERGENCY LOWERING. This condition occurs when power to the pumps is not available or something else has happened to prevent the pumps from working and providing the required flow and pressure required for lowering.

2.2.2.1 EMERGENCY LOWERING WITH GATE ON THE LATCH PINS. At the gate to be lowered:

1. Remove 3000 psi A-port pressure gauge at its quick disconnect fitting.(Figure 4)

2. Attach output hose of hydraulic hand pump to this quick disconnect fitting.(Figure 7)

3. Use the hand pump to supply oil to raise the gate off the latch pins.

4. Remove hydraulic hand pump hose from quick disconnect.

5. Attach output hose of hydraulic hand pump to B-port quick disconnect on the latch pin valve stack. (Figure 4)

6. Use hand pump to supply oil to retract latch pins. A sudden increase in pressure indicates the latch pins are retracted.

7. Turn screw on the relief valve 3ACP, located on the underside of the panel, in a clockwise (figure 4 direction until the gate starts to lower. Valve 17SB, flow control valve at the bottom of each hoist cylinder provides overspeed protection so gate speed will be limited no matter how far the the screw on valve 3ACP is turned.

Turn the screw counterclockwise to stop the gate.

8.NOTE: ALWAYS LEAVE VALVE 1CP I N THE CENTER POSITION DURING

EMERGENCY LOWERING OF THE GATE.

If valve 1CP is accidentally left in the raise position, the pumps will rotate during emergency lower. Although the system has been designed to resist damage in this case, it should not be operated in this manner.

2 . 2 . 2 . 2 EMERGENCY LOWERING WITH GATE AT INTERMEDIATE P O S I T I O N .

1. Turn screw of valve 3ACP clockwise to lower the gate.

(Figure 4). Turn the screw counterclockwise to stop the gate.

2.NOTE: ALWAYS LEAVE VALVE 1 C P I N THE CENTER P O S I T I O N DURING

EMERGENCY LOWERING O F THE GATE.

3. Reset relief valve 3ACP setting to original position.

2.2.3 FORCING THE GATE DOWN.

EXTREME CARE MUST BE TAKEN PRIOR TO PERFORMING THE OPERATION.

T H I S METHOD O F OPERATION I S ONLY INTENDED TO BE USED I F THE

NORMAL LOWERING FORCES ARE NOT S U F F I C I E N T TO CAUSE THE GATE TO

LOWER. I T 16 NOT INTENDED TO POWER THE GATE DOWN I F THE GATE I S

S T I C K I N G OR TO PUSH THE GATE THROUGH D E B R I S I N THE GATE SLOT.

DURING FORCING THE GATE DOWN, MONITOR GATE P O S I T I O N AND CYLINDER

PRESSURE EXTREMELY CLOSE. T H I S W I L L BE YOUR TOOL TO DETERMINE

I F I T IS THE INCREASED WATER LOAD CAUSING THE GATE TO S T O P OR I F

I T I S D E B R I S I N THE SLOT.

1. Turn on pumps. (Figure 6)

2 . Shift valve 1CP to gate raise position.(Figure 4)

3. Shift valve 6CP to the unlatch position.

Shift valve 1CP to gate lower position.

5. The gate moves to some intermediate position and stops.

6. Move valve 1CP back to the raise position to make sure it is not debris that is preventing the gate from lowering.

Raising the gate a few feet is intended to allow trash that may be preventing closure to be flushed out. If the cylinder pressure suddenly dropped, gauge (19CP), it is an indication that debris is probably causing the problem. If the cylinder pressure has been slowly reducing it is an indication that it is the increased load caused by the water load.

7. Move valve 1CP to the lower position. Watch position indicator as gate lowers. If gate stops at the previous location, repeat previous step and this step. Watch gate position indicator to learn the relative gate speed. If the gate stops quickly it is an indication that trash has blocked its travel. If the gate movement begins to slow down and gradually stops it indicates than an increasing water load is the source of the problem. If increasing water load is the source of the problem follow the next steps to lower the g a t e .

8. s lowly i n c r e a s e p r e s s u r e r e l i e f va lve 3ACP p r e s s u r e s e t t i n g .

9 . Watch p r e s s u r e gauge (18CP) on t h i s l i n e , o r connect e l e c t r o n i c p r e s s u r e meter t o quick connect t o p reven t r e l i e f v a l v e 3ACP from being ad jus t ed s o t h e p re s su re would exceed 750 p s i .

10. I f t h e g a t e does n o t move down wi th t h e a d d i t i o n a l f o r c e of 120,000 l b . a t 750 p s i . s t o p t h e opera t ion . Any f u r t h e r f o r c i n g may cause damage t o t h e g a t e o r cy l inde r .

11. A t t h e end of t h e ope ra t ion RESET THE RELIEF VALVE 3ACP

TO THE ORIGINAL POSITION, 2000 P S I MINIMUM. FAILURE TO DO

THIS COULD LEAD TO A MAJOR PROBLEM DURING OTHER OPERATIONS.

1 2 . Return va lve 1CP t o t h e hold p o s i t i o n when t h e g a t e reaches t h e d e s i r e d p o s i t i o n .

13. Turn o f f pumps.

Following is t h e d e t a i l e d d i scuss ion of s t e p s f o r f o r c i n g t h e g a t e down.

1. Turn on t h e pumps us ing t h e push bu t ton s t a t i o n l o c a t e d a t t h e g a t e e l e c t r i c a l c o n t r o l c a b i n e t . When t h e pumps a r e on they charge t h e high p r e s s u r e header t o 3100 p s i . t h e p r e s s u r e compensating f e a t u r e t hen ho lds t h e header a t t h a t p r e s s u r e wi th no flow u n t i l v a l v e 1CP is moved.

2 . Move t h e 4-way_ va lve 1CP t o t h e r a i s e p o s i t i o n . The g a t e now s t a r t s t o r a i s e . The g a t e r a i s e s a smal l amount t o t a k e t h e g a t e weight o f f of t h e l a t c h p i n s . Leave v a l v e 1CP i n t h e r a i s e p o s i t i o n u n t i l l a t c h p i n s have been r e t r a c t e d and you a r e ready t o lower.

3. Unlatch t h e q a t e l a t c h p ins . S h i f t va lve 6CP t o t h e un la t ch p o s i t i o n . Leave va lve 6CP i n t h a t p o s i t i o n a t t h e completion of t h e lowering ope ra t ion .

4 . ------ Move va lve 1CP t o t h e lower p o s i t i o n . The g a t e now s t a r t s t o lower.

For normal lowering, t h e pumps need t o be running t o p rov ide p r e s s u r e t o o p e r a t e t h e counte rba lance va lve . The counterbalance v a l v e is used t o c o n t r o l t h e g a t e speed dur ing lowering. The pumps must main ta in p r e s s u r e t o o p e r a t e t h e counterbalance va lve dur ing lowering ope ra t ions . I f t h e flow through t h e counterbalance v a l v e exceeds punlp ou tpu t t h e p i l o t p r e s su re s t a r t s t o drop, a l lowing t h e p i l o t v a l v e t o s t a r t t o c l o s e t h u s causing t h e counterbalance v a l v e t o modulate t h e flow and t h u s slowing t h e g a t e down.

5. Gate stops. If the gate stops, it means that either debris has jammed the gate and it cannot move any further or that the friction caused by the high head exceeds that expected. The cause of the gate stoppage needs to be determined.

6. Move valve 1CP to the raise position. This allows the gate to raise. Move valve 1CP back to the raise position to make sure it is not debris that is preventing the gate from lowering. If the cylinder pressure suddenly dropped it is an indication that debris is probably causing the problem if the cylinder pressure has been slowly reducing it is an indication that it is the increased load caused by the water pressure.

7. Move valve 1CP to the lower position. The gate should move down to the position where it was when it previously stopped. If it does not it probably indicates that the problem is debris and was not cleared out as the water load should normally stop it at the same relative position. If it continues to move past that point it means the debris was cleared out and that normal lowering can continue. If it stops go to the next step.

8. Increase relief valve 3ACP settinq. Increasing the relief valve setting allows pilot pressure to exceed that required for no tension load on the cylinder rod. The higher pressure will then apply a downward force on the piston, forcing the gate down.

9. NOT EXCEED 750 PSI. When adjusting relief valve 3ACP watch the pressure gauge closely so the system does not exceed 750 psi. Exceeding this will damage the gate and cylinders. If the gate does not go down with this additional force the reason needs to be determined prior to proceeding with any further lowering operation.

10. Reset relief valve 3ACP to orisinal settins.

Immediately upon completion of this operation reset the relief valve 3ACP to the original setting.(380 psi).

11. Return valve ICP to the center position.

PART I1 - MAINTENANCE

3. GATE REMOVAL

1. Raise and latch sate

2. Turn off pumps

3. Open ball valve at the end of hiqh pressure header.

(Figure 8)

This will depressurize the header so that hoses can be safely disconnected.

4.Connect air bleed hoses to bleed valves in the gate slot (Figure 9)

Route the hoses to a container and open the bleed valves.

This will relieve any residual back pressure present in the lines. After bleeding off pressure, close the bleed valves and remove the hoses.

5. Shut off power at the motor control center FC01 and control power at panel PR1 (Fisure 21).

6. Disconnect latch cylinder limit switch wirinq at the junction box on the support beam. (Figure 9)

7. Disconnect gate position transducer wirins. (Figure 6).

The connection is an Amphenol connector located inside the support beam at the south end. The connection is at the rotating parts assembly. (Figure 19)

8. Disconnect 1" and 3/8" hoses where they meet the support beam. Put a drip pan or rags underneath the hose connections. Disconnect and plug hose ends. Unhook the cable grips (Figure 8) which support the hoses. Pull the hoses back through the opening in the concrete.

Disconnect backup gate position indicator cable after blocking the cable reel to ensure it will not rotate. (Figure 1)

9. Connect the 4-lessed slinq &Q the sup~ort G ~ a m (Figure 5)

10. Lift aate with the 90 ton crane until the bottom of the gate is just above the deck. The loads for lifting the gate are listed below. Remove the bottom orifice plates which are in line with the cylinders. (Figure 10)

JUNCTION BOX

IT SWITCHES)

PORT

B - P O R ~

HOSE

BLEED VALVE

HOSE A-PORT

(LATCH) - . g

CONNECTION

(LATCH) -

FIGURE 9 SUPPORT BEAM PIPING

LOADS

Gate - 75000 l b s Cyl inder (each of 2 ) - 5000 l b s Support beam - 10600 l b s 4 legged s l i n g - 480 l b s Spreader b a r - 1155 l b s Block - 2600 l b s Wire rope - 1050 l b s

11. I n s t a l l p ry b a r underneath the c v l i n d e r rod eve and s l i g h t l y l i f t t h e eye t o g e t t h e load o f f of t h e p i n . ( F i g u r e

10) Remove one c o t t e r p i n and d r i v e t h e p i n ou t .

1 2 . Lower t h e s a t e u n t i l t h e t o p of t h e g a t e is j u s t below t h e deck. At tach t h e gate dogging beams and rope t o t h e l i f t eyes a t each extreme end of t h e g a t e . Lower t h e g a t e s o it is supported by t h e dogging beams. (F igure 5)

13. Attach hand pump t o t h e B-port connect ion ( l a t c h ) .

(F igure 9 and 11) Pump u n t i l t h e l a t c h p i n s a r e f u l l y r e t r a c t e d . F i l l t h e hand pump r e s e r v o i r wi th Texaco Rando AZ o i l .

1 4 . L i f t t h e c y l i n d e r and suppor t beam. Lay t h e assembly down on c r i b b i n g on t h e deck wi th t h e suppor t beam p i p i n g f a c i n g upward o r p l a c e it i n an empty ope ra t ing g a t e o r bulkhead s l o t . I f p laced i n a bulkhead s l o t , t h e suppor t beam w i l l be above deck l e v e l .

15. At tach the 4-lessed s l i n q t o t h e sp reade r bar . At tach t h e sp reade r b a r t o t h e g a t e l i f t i n g e a r s . (F igure 1 2 ) L i f t t h e g a t e o u t of t h e s l o t a f t e r removing t h e dogging beams.

(F igure 13) Lay t h e g a t e down on c r i b b i n g o r p l a c e it i n an empty g a t e s l o t and dog it o f f wi th t h e dogging beams and cab le s .

4 . GATE INSTALLATION

1. Attach the 4-lesged s l i n q t o t h e sp reade r ba r . (F igure 1 2 ) At tach t h e sp reade r b a r t o t h e g a t e l i f t i n g e a r s . Ra ise t h e g a t e o f f of t h e c r i b b i n g on t h e deck. Put t h e g a t e i n t h e ope ra t ing g a t e s l o t . ( F i g u r e 13) I n s t a l l t h e g a t e dogging beams. Remove t h e sp reade r ba r .

2 . Attach the 4-lesaed s l i n q t o t h e s u p ~ o r t beam. (F igure 5 ) Ra ise t h e assembly t o a v e r t i c a l p o s i t i o n . Guide t h e c y l i n d e r s i n t o t h e h o l e s i n t h e g a t e and lower t h e c y l i n d e r s .

(F igure 1 4 )

3 . Remove bottom o r i f i c e p l a t e s which a r e i n l i n e wi th t h e cvlinders.(Figure 10) Use a pry bar to position the rod eye and insert the pin. Install the cotter pin. Install the orifice plates.

4. Connect hand pump hose to A-port (latch) connection.

(Fisure 91. Use hand pump to engage latch pins.(Figure 11)

5. Remove gate doqqinq beams.(Figure 14) Lower the gate until the support beam rests on the rocker pads. Install hold down plates and nuts finger tight. (Dwg. S-17, appendix)

6. Connect hvdraulic hoses. and flexible conduit. (Figures 6 and 9)

7. Connect bleed hoses to bleed valves. Run open end of hoses to container. Start to lower gate, then slightly open bleed valve connected to rod end of cylinder. Continue until air no longer appears. Close this valve. Start to raise the gate, then slightly open the bleed valve connected to the blind end of the cylinder. Continue until air no longer appears. Repeat this until air is eliminated.

Also repeat this procedure to bleed the latch cylinder piping.

5. INSTALLATION OF EMERGENCY GATE

1. This procedure' is for installing an emergency gate (downstream gate slots) before or during flood conditions.

These gates would only need to be employed if the operating gate hoists failed to close the operating gates. Using the 90 ton, PtH model 790 crane, the maximum safe pool elevation for lowering an emergency gate is El. 490 with an 80 foot boom and El. 503 with a 50 foot boom. Knowing that the crane is set up with an 80 foot boom, it is unlikely that the 50 foot boom configuration would be utilized. Capabilities for the the 50 foot boom are listed for reference should extenuating circumstances require its use.

With the modified gate configuration intended to ensure closure, there are significant water loads which force the gate down during flood conditions.

LOADS

50 ft boom 80 foot boom (13 '-611 radius) (20' radius)

Gate - 4 legged sling - Spreader bar - Block -

75000 lbs 75000 lbs 480 lbs 480 lbs 1155 lbs 1155 lbs 2600 lbs 2600 lbs

ACCEPTABLE DECK

I LOADING AREA-

\ I

STORAGE SLOT EMERGENCY

CLOSURE SLOT

I

I

OPERATING GATE SLOT

BULKHEAD SLOT

+ W Q Z - 6 O U W 0 m

* O

7 J W = z o o

ACCEPTABLE DECK]

LOADING AREA

I

SCALE: 3 / i 6"=11-0"

V

A

N

W

N b'

N l8

M

'W

O O

'E d s b

'8 b

'la n i

Wire rope -

S u b t o t a l

1050 l b s 1050 l b s --------- ---------- 80300 l b s 80300 l b s

N e t v e r t i c a l wate r l oad , 83700 l b s 27700 l b s downpull, and f r i c t i o n

T o t a l 164000 l b s 108000 l b s

MAX POOL ELEVATION FOR

EMERGENCY CLOSURE EL. 503 EL. 490

The procedure below a p p l i e s t o bo th t h e 80 and 50 f o o t boom.

2 . P o s i t i o n t h e c r ane on t h e deck a s shown on F igure 15.

3. U s e t h e c r ane t o remove t h e conc re t e ha tch covers from t h e downstream bulkhead s l o t r e q u i r i n g t h e emergency g a t e and t h e s l o t i n which t h e emergency g a t e is s t o r e d . There a r e two emergency g a t e s , one s p a r e g a t e which is e s s e n t i a l l y t h e same a s t h e ope ra t ing g a t e s and one bulkhead which is t h e same except it has a b o l t e d s p l i c e a t t h e middle and cannot be f i t t e d wi th hydrau l i c c y l i n d e r s . (dwgs. S-2, S-3 and S-4 i n t h e appendix) Refer t o p r o j e c t r eco rds o r check each s l o t t o determine which s l o t s t h e g a t e s a r e s t o r e d i n .

4 . Connect 4 legged s l i n g t o sp reade r bar . (F igu re 1 2 )

5. Connect spreader b a r t o emergency g a t e . ( ~ i g u r e 13)

6. L i f t t h e emergency g a t e s l i g h t l y t o provide some s l a c k i n t h e two dogging cab le s .

7. Remove t h e dogging c a b l e socke t p i n s from t h e emergency g a t e dogging e a r s . Remove t h e two 1 2 " long dogging beams from t h e main dogging suppor t beams and e x t r a c t t h e c a b l e s through t h e openings i n t h e suppor t beams. (F igure 16)

8. P lace wood block over t h e emergency g a t e dogging e a r s .

Blocks should be p r e f a b r i c a t e d and s t o r e d a t t h e c o n t r o l s t r u c t u r e . (F igure 17)

9. Raise t h e emergency g a t e w i th t h e c r ane u n t i l b locks c o n t a c t main dogging suppor t beam. Continue r a i s i n g t h e g a t e u n t i l t h e bottom of t h e main dogging beam is a t deck l e v e l .

10. S l i d e t h e main dogging beams o f f of t h e wood b locks on to t h e conc re t e deck j u s t f r e e of t h e ends of t h e s t o r a g e s l o t .

Remove t h e wood b locks from t h e g a t e dogging e a r s .

11. Raise t h e emergency g a t e o u t of t h e s l o t i n which it is s t o r e d and p l a c e it i n t h e s l o t where t h e emergency c l o s u r e is t o be done. I n some cases , t h e emergency c l o s u r e s l o t will not be adjacent to the storage slot so it will be necessary to first set the gate in the slot between, then hang it from the main dogging support beams and cables.

Next, set the crane up in a new position so it can place the gate in the emergency closure slot.

11. Lower the emergency gate to the fully closed position.

Do not attempt to regulate flow by stopping the gate at an intermediate position. Do not raise the gate since this can also overload the crane.

12. If the water level is low enough, have a man go down in the slot with a ladder to disconnect the block from the four-legged sling. Otherwise, it will be necessary to leave the crane connected to the gate until the water level recedes.

Replace the main dogging beams. Tie off the top link of the 4-legged sling to the main dogging beams. Replace the concrete hatch covers.

6. CYLINDER MAINTENANCE

1. Cylinder Troubleshootins.

Problem Cause

Excessive drift when gate is in Excessive piston seal a regulating position. leakage

Excessive A-port ball valve leakage

Rod seal, cylinder tube seal or support beam piping leakage

Metallic scraping noise when Piston bearing ring failure cylinder is operated

Rod bearing failure

Oil in operating gate slot Rod seal leakage cylinder tube seal or support beam piping leakage

Unequal cylinder travel Air in cylinder or piping failure of flow control valve trash in gate slot gate slot piping leakage

Rod seal leakage

Piston seal leakage

Bent rod

Scratched chrome on rod seal wear wiper failure

Pitting of internal cylinder wall caused by excessive water content in oil seal wear scratched bore

Excessive B-port pressure if gate was forced down

Excessive water content in oil Water absorbing filter bypassing

Water saturated oil was reclaimed and put into system

Excessive condensation in oil reservoir. Replace breather with dessicant breather.

Temperature setting of reservoir heater too high.

2. Cylinder Removal. With the cylinder and support beam assembly laid down on the deck, and the support beam piping facing upward, use a fork-lift or a crane to support the weight of the cylinder. Use wooden blocks or web slings to avoid damage to the paint on the cylinder. Remove the eight 2" diameter capscrews which fasten the cylinder to the support beam. Disconnect the two hoses at the top of each cylinder. The south cylinder on each support beam has a transducer assembly at the top. To remove these cylinders, raise the cylinder 2" to 3" and shift it 1" to 3" toward the center of the support beam. The cylinder must be offset during removal or damage to the rotating parts assembly will occur,since the edge of the housing overlaps the edge of the hole which is cut in the support beam. Swing the rod end of the cylinder away from the center of the support beam to clear the transducer housing from inside the support beam.

Once the transducer housing is clear, the cylinder may be laid down. On the north cylinder, there is no transducer assembly so the cylinder can be pulled straight out from the support beam.

3. Piston Seal Leakage Testins. To check the condition of the piston seals, lower the gate to some arbitrary position.

Close the A-port ball valve. Remove the handle of the A-port ball valve. Disconnect the bottom connection of the A-port ball valve on the control panel. DO NOT LOOSEN THE TOP CONNECTION OF THE BALL VALVE. Place a container under the ball valve. Record the pressure, gate position, and test starting time. The test should last a minimum of one hour and should preferably be 24 hours. At the end of the test record the pressure, gate position and test starting time.

Determine the total leakage as follows:

Total leakage =(Starting position - Final position)* 1.8

Starting and final position must be measured in inches.

Total leakage is measured in ounces.

Measure the quantity of fluid in the container underneath the A-port ball valve.

Piston seal leakage = Total leakage - Ball valve leakage

Total leakage rate = Total leakage

Time

Piston seal leakage rate = Piston seal leakage

Time

Time should be measured in hours.

Total leakage rate should be in the range of 0 to 1.5 ounce per hour.

Piston seal leakage rate should be in the range of 0 to

1.3 ounces per hour.

If leakage is within the above range, no repairs are recommended. If leakage is outside of this range, an assessment should be made as to whether the leakage rate is acceptable for operation of the project and if not repairs are necessary for acceptable operation of the project.

4. Rod Seal Leakage Testinq. Visually inspect the water surface in the gate slot for signs of oil film. If there is an oil film, the most likely leakage point is the rod seals.

When the water level has receded to below elevation 490, with a man on top of the gate, lower the gate fully, and visually inspect on the surface of the rods of both cylinders for signs of leakage. If leakage is present, the cylinders must be removed for repair. Also check all gate slot piping and cylinder tube seals for signs of leakage.

5. Cvlinder disassemblv.(Figure 18) Disassembly should preferably be done with the cylinder in a vertical position to minimize the possibility of damaging the piston and seal upon removal. Drain the cylinder before disassembly. This may be done with the cylinder horizontal by opening the bleed port and unplugging the 1" high pressure hose. Drain the oil into a container(s). If the oil is to be reclaimed, the container(s) must be clean. Each cylinder holds about 52 gallons of oil.

If the cylinder is to be disassembled in one of the operating or emergency gate slots, invert the cylinder, place it over one of the 14" square holes of the operating gate and securely brace the cylinder to prevent tipping.

Disassemble the cylinder only in clean and dry conditions.

Remove the 12 capscrews of the rod end cylinder head.

Connect a web sling to the rod eye. Estimated weight of the rod and head assembly is 2200 lbs. Make sure that both cylinder ports are unplugged. Slowly lift the rod up until the piston is nearly clear from the cylinder bore. Guide the bottom of the rod by hand as the piston comes free from the bore.

The rod assembly should be carefully laid down onto cribbing with special attention to avoid any damage to the rod or piston surfaces. Remove the cylinder tube assembly and lay it down on cribbing. Remove the blind end flange.

At this point the cylinder bore may be wiped clean and inspected and piston seals and bearings can be inspected for signs of wear and damage. As a general practice, all seals should be replaced when the cylinder is reassembled.

Attempting removal of the piston from the rod is not recommended. The piston is torqued to an extremely high value to prevent it from loosening during operation.

When inspecting the cylinder bore, special attention should be paid to checking the bottom 1 foot of the cylinder.

Pitting of the cylinder walls here indicates the presence of water and means that either water saturated oil has been added to the system or that the water absorbing filter at the reservoir has been in bypass mode. The bore should also be inspected for scratches. Scratches may be due to dirt or a broken piece which has gotten into the cylinder.

If either pits or scratches are present, it is probably necessary to have the cylinder repaired in order to restore an acceptable piston seal leakage rate.

It is recommended that the cylinder manufacturer, The Rexroth Corporation, (formerly WABCO), Lexington, Kentucky,(606) 254- 8031, be consulted before any major cylinder repairs are undertaken. If any cylinder parts are to be stored for an extended period of time, they should be coated with oil and wrapped in paper or plastic and boxed. The recommended oil is Texaco Rando AZ. No other oil should be used without a thorough investigation of compatibility. Incompatible oils may form compounds which are harmful to the cylinder and the rest of the hydraulic system.

There is one spare cylinder with rotating parts assembly. It is interchangeable with all other cylinders.

6. Cylinder Assembly. Assembly is the reverse procedure of disassembly. Recommended head bolt torque is 1000 ft.-lbs.

Once the cylinder is assembled, with the rod retracted, open the bleed port and fill through the rod end piping until the cylinder is full. Leave a small volume of air in the cylinder, approximately 1 gallon, to account for expansion of the oil as the temperature changes.

7. Rotatinq parts assembly. (Figure 19) The rotating parts assembly is located at the top of each south hoist cylinder, inside the support beam.

Rotatinq Parts Assembly Troubleshootins.

Problem Cause

Cylinder operates, but shaft does not rotate cable is not engaged with cable anchor nut roll pin, part 21, missing or broken cable or machined stop broken broken power spring or arbor

Leakage from the rotating parts assembly damaged seal 1-S or 2-S or worn shaft damaged o-ring,5-S 6-S, or groove at base of rotating parts assembly damaged o-ring, 3-S 4-Sf or groove

No signal from rotating parts encoder is faulty assembly as shaft rotates check wiring

Removal

Refer to figure 19, drawing D-105-478, by Fluid Air Components.

Remove the cylinder from the support beam.

Make sure the cylinder is drained before proceeding.

Place wrench on hex of part 12, spring drum. Remove 4 , 1/4" capscrews, part 26. Rotate spring drum to relieve tension on the spring and count the number of turns as it is unwound. This is the number of turns for spring prewind.

Prewind should be 3 turns. Replace the 4, 1/411 capscrews to retain the spring drum. Remove the 4 socket head capscrews which fasten the rotating parts assembly to the cylinder.

Pull the rotating parts assembly away from the cylinder and set it on a block.