Installation and Operation of American Turbine Submersible Pumps

Contents

Submersible Installation
Equipment Needed
Use of this Equipment

Repair Instructions
Tools Needed
General
Disassembly Instructions

Assembly

Submersible Installation

A routine installation procedure should be established for installing submersibles. Such a procedure will make troubleshooting in the future infinitely easier. BEFORE INSTALLATION, do the following things.

1. Inspect pump-motor parts for shipping damage.
2. Inspect check valve for dirt or trash. Make sure it operates freely.
3. Measure depth of well. Allow at least 3 feet from bottom of pump-motor. If pumping from sand formation use shroud to insure water velocity around motor.
4. Measure water level in well. If possible, use test pump to determine well performance.
5. Inspect casing for roughness and sharp edges that might cause damage to the motor cable.

Equipment Needed

There is a minimum amount of electrical equipment needed for this operation.

Voltmeter/Ammeter - used to measure current and voltage under operating conditions.

Ohmmeter - used to take low resistance readings such as motor windings, starter contact resistance, check continuity, and check capacitors.

Megger - used to check cable and motor winding insulation resistance under high voltage conditions.

Use of this Equipment

All data should be taken and recorded for each pump and referred to when service is necessary.

1. Measure and record resistance values of the motor windings before the cable is spliced. These values will be low-falling in the range of ½ to several ohms depending on the size, type and make of motor. For three-phase motors all three windings will be equal. For single-phase motors with three leads, the values will be different. Read the record by the color code of the wires.

2. Check the megger and record the insulation resistance between the windings and the motor case. These values will be high, ranging over 100,000,000 ohms.

3. Record the data from the motor name plate. Check the motor voltage against the motor voltage at the starter. Record the full load motor current. NOTE: Submersible motors are not dual voltage motors.

4. Make the cable splice and repeat the check shown in the first and second step. These values can be compared to the final installation values to check against a leak in the cable or splice. The insulation value may drop down to a value as low as 10,000,000 ohms in the surface check.

5. Install the pump carefully. Do not let the pump spin and protect the cable from edge of casing at all times. After the pump and motor is submerged, check the insulation to make sure no leak has shown up in the cable or splice. The cable should be checked after each joint of pipe is installed. This will isolate any break in the cable during installation and eliminate unnecessary work.

6. When the pump is completely installed, repeat all measurements in the first and second step. These values can be used at a later date to check for service problems.

7. Wire up the starter. Check voltages to make sure the correct power is available. Clamp the ammeter to one of the leads and start the pump. Record the current values for future use. For single phase motors the red lead is the starting winding and after starting should drop to 0 or a very low value.

Repair Instructions

Tools Needed

Locating Plate - applicable for pump and motor.
Locating Tool - applicable for pump and motor.
Collet Tool - applicable for pump bowl.
General line of pipe wrenches, chain tongs, allen head set screw wrenches, 6" machinist scale and other miscellaneous hand tools.

General

Submersible pump bowl repair is very similar to standard line shaft pump bowl repair. One of the most important differences is that the submersible motor thrust bearing will not stand shock loads or poundings. Before any work is performed on the bowl assembly, the motor should be disconnected and set aside. The other important difference is that the lateral in the submersible bowl assembly is established by contact between the end of the pump bowl shaft and the motor shaft, and is not adjustable after the motor and pump have been assembled. This is done be the special locating tools listed above. The bowl assembly should never be assembled by locating the shaft with the motor because the pounding associated with the collet driver would damage or ruin the motor thrust bearing.

Disassembly Instructions

1. Remove the cable guard from the bowl assembly. Take special precautions not nick or kink motor cable leads.

2. Remove the four cap screws or nuts from the motor adapter connections. Make sure the motor and bowl are supported so that the removal of these bolts will not allow the motor to sag down which would bend either the bowl shaft, motor shaft or both.

3. Slip the motor out of the splice connection in the coupling, if the coupling is keyed to both shafts, loosen bowl shaft, set screws, and remove the coupling with motor.

4. Set the motor aside, making sure that the cable is not on the floor where it may be walked on or damaged by dropping tools. Motor electrical check is found in the manufacturer's bulletin on the motor. The motor stub shaft may be checked for wear in the splice or on the face. Also mechanical rotation of the shaft should be observed. It should not be hard to rotate by hand. A good Kingsberry-type bearing will show a slight resistance to starting rotation; however, as soon as the shaft is rotated ¼ to ½ around, it should become easy to spin and keep spinning by hand. Check the wear with the motor standing vertically, clamp the dial indicator to the top end bell. Move the shaft back and forth against the dial indicator, observing the total movement. This reading should not be more than (.002 to .004 for a Franklin motor), or (.006 to .008 for a Pleuger motor). Movement in excess of these amounts will allow the motor to drag the liner of the stator eventually shorting out. If the journal wear checks within tolerances, rotate the shaft against the dial indicator and check for run out. There should not be more than (.001 TIR. for Franklin motors), or (.004 TIR for Pleuger motors). Any more than this indicates a bent rotor shaft. Check the end play of the rotor. Lay the motor horizontally and clamp the dial indicator so that the movement will be lateral against the face of the stub shaft. Move the motor shaft in and out against the thrust bearing in the bottom and the upthrust spacers in the top of the motor. The reading should be no more than follows:

.004 Min - .030 Max 4" Franklin
.020 Min - .045 Max 6" Franklin
.022 Min - .120 Max 10" Pleuger

Excess end play indicates either worn main thrust bearing in the bottom of the motor, or upthrust washers in the top. This may be further checked by measuring the stickup of the shaft above the end bell of the motor, which bolts to the pump suction adapter. This dimension should be as follows:

4" motors .............1.505 (± .005)
6" motors..............2.875 (± .005)
8" motors..............4.000 (± .010)
10" motors.............4.000 (± .010)

Any lower shaft extension than this and excessive end play will definitely indicate worn thrust bearings. If any of the mechanical checks above or the electrical checks show the motor to be defective, return it to AMERICAN TURBINE PUMP CO. INC. for repairs or exchange.

5. Remove the check valve, bushings, and fittings. Examine the check valve for any wear in the seat or poppet and repair or replace.

6. Unbolt or unscrew the discharge case.

7. With an allen head set screw wrench, remove the discharge case sand collar.

8. Remove the top intermediate bowl. This exposes the topmost impeller.

9. In order to remove the impellers, it is necessary to push up on the coupling end of the shaft so that the collet tool may drive the impellers down toward the shells to loosen them from the collets. Either the coupling should be removed or a round piece of hardwood made to fit the spline bore to push upward against the bottom of the shaft. It is not recommended to push the shaft up and hold it up by pushing on the coupling. If a coupling is keyed, it may slip on the shaft, marring the face of the spline or damaging the spline in the motor end. To remove the couplings, the metal doors or the pipe plugs in the suction adapter must removed. If the coupling is the key type coupling access to either one or two set screws is through the metal door openings or the pipe plug holes.

10. Keep pressure on the collet end of the shaft. With the collet tool, drive the impellers down off the collet with the recessed end of the collet tool. The collet tool should be continually checked to make sure the recess is not flared which will cause it to strike the collet. This drives the collet in, tightening the impeller. Continue removing impellers and shells until the bottom impeller is removed.

11. If the coupling has been removed, the shaft will then slip out of the suction adapter. If the coupling is still on the shaft it will be necessary to reach down through the impeller area with an allen wrench, loosen the set screw in the sand collar, remove the sand collar, then move the shaft down through the bottom of the suction adapter.

12. After the shaft has been removed, take off all remaining items. If the shaft is in good shape and shows no wear, it may be checked for straightness and then be re-used. The shaft must be checked on V-blocks with a dial indicator and should have no more than .003 TIR.

13. The suction adapter screen may be removed for replacement or cleaning by drilling out the stainless rivets.

14. All bushings in the intermediate bowls, discharge case and suction adapter may be replaced in the conventional manner.

15. If wear rings are not installed, the bowl may be bored to accept the wear ring.

16. Impellers may be replaced or wear ringed, or re-wear ringed.

Assembly

The submersible pump must be assembled for the particular type of motor and motor coupling. Locating tools are designed for all combinations of bowls and motors. All couplings depend upon the direct transmission of thrust from the pumping assembly to the motor by direct contact between the pump shaft and the motor shaft. The Franklin couplings are built with a small spacer in the coupling against which both the bowl shaft and the motor shaft make contact. This spacer must be allowed for in assembly to obtain proper location of impellers. Care must be exercised in assembling all submersibles to make sure alignment is correct and there is not dragging or hard spot when the shaft is rotated. Extreme caution must be used in assembling impellers and bowls so as not to bend the impeller shaft.

1. The locating plate must be used.

2. The size of the locating tool to be screwed onto the locating plate is determined by the size bowl assembly and motor with the type coupling used. Select the proper tool and spacer, slip the spacer on the threaded end of the tool and screw it into the locating plate. The hold through the locating tool is to be used with a bar to tighten the tool to the plate sufficient to hold the tool properly. Next, make sure the top face of the locating tool and the face of the locating plate as well as the motor flange of the suction adapter are clean and free of burrs. Bolt the locating plate securely to the bottom of the adapter.

3. Check the bottom of the bowl shaft to make sure it is free of burrs and has a mirror-smooth face.

4. Grease pack suction bearing with AMERICAN TURBINE GREASE for submersible pumps.

5. Insert the bowl shaft through the bearing with the locating hole toward the locating tool.

6. Secure the bowl shaft tight against the locating tool with a threaded bolt.

7. Install the suction adapter bearing sand collar over the suction adapter bearing. Push all the way against the housing and tighten set screw.

8. Install bottom impeller and collet with small end of collet driver tool. Screw or (bolt) on first intermediate stage and butt up tight against the suction adapter.

9. Install second impeller and collet.

10. Screw or bolt on second intermediate bowl.

11. Continue in this fashion until all impellers and intermediate bowls have been installed.

NOTE: If the bowl assembly consists of ten or more stages, it will be necessary to follow a slightly different procedure for assembling bowls and impellers. it has been found from experience that a collet type impeller will bend (much like the bottom of an oil can when pressed with the thumb) as it is driven into place with the collet driver tool. Regardless of the size of the impeller this deflection amounts to approximately .010" and this deflection becomes important when there are a large number of impellers. Each impeller assembled to the shaft pulls on the shaft a little more then the previous impeller and by the time the top one is installed the total pull on the shaft is considerable. This may be observed by assembling a large number of stages and then removing the licking screw in the bottom of the locating plate. The shaft will be observed to pull away from the end of the locking tool by as much as 1/8". This means the bottom of the impellers are being pulled up in relation to the top impellers. Thus the impellers do not have there correct location. To eliminate this on long bowls, it is necessary to install the impellers in the bowl with the bowl spaced off the next bowl by .010". This is done by using a .010" feeler gauge between the bowl and the proceeding bowl. As soon as the impeller is locked against the bowl, remove the feeler gauge and finish tightening the bowl against the previous bowl. Be careful not to drive the collet all the way into the impeller, by continuing to hammer on the impeller. The defection obtained in such an action will be considerable more than .010" indicated above. The collet should be not closer than 1/32" to the top of the impeller.

12. Do not install the topmost bowl covering the last impeller.

13. Remove the bowl shaft lock screw and locating tool from the suction adapter.

14. Rotate the top end of the shaft by hand, observing the ease of rotation. it should not drag or catch. If it does, dismantle the bowl stage by stage, rotating the assembly after each stage is removed to check for the stage or stages causing the interference. Correct the troubles and reassemble.

15. Measure the mark down the distance from the face of the top bowl to some convenient point on the impeller with the impeller all the way down and all the way up. This dimension is referred to after the motor is buckled to the pump to make sure the impellers are not dragging on the bottom, not dragging against the top. They should be somewhere between 1/3 and 2/3 of the distance measured and noted. This same movement should be noted at the bottom of the sand collar through the suction adapter screen. This is actually where the impeller spacing will be observed.

16. Install the top intermediate bowl.

17. Slip the discharge case sand collar on the shaft.

18. Snug the set screw slightly so the sand collar will have some resistance to slipping.

19. Slip the discharge case onto the shaft, pushing the sand collar as far as it will go.

20. Screw or bolt the discharge case into final position.

21. Push the bottom end of the impeller shaft all the way up. Observe the bottom sand collar to make sure that the maximum up position observed in step 15 is still available. This locates the top sand collar so that it will not rub against the bearing housing even if the impellers float during starting.

22. Remove the discharge case.

23. Lock the discharge case sand collar into place in this position.

24. Install the discharge case. (DO NOT TIGHTEN).

25. Work the impeller shaft up and down to sure the full amount of lateral is still available. If it is not, it is probable due to the fact that the sand collar slipped toward the top end of the shaft when the discharge case was removed. Remove the discharge case and reset the set screw on the sand collar. Also check clearance between the top of the impeller and the set screw.

26. Tighten the bowl assembly with chain tongs or wrenches with the exception of the discharge case.

27. Install the coupling with button, the coupling should be pushed up all way on the impeller shaft so that the impeller shaft rests firmly against the button. Lock the set screws against the key firmly. If the coupling is of the key type, it will be observed that there is an annular groove somewhere the center of the coupling. This is the area which the two shafts should butt.

If the coupling is keyed to both the motor and the pump shaft, install the coupling on the motor shaft first. Screw it so that the motor shaft extends slightly into the annular groove. If the coupling is splined to the motor, install it on the ump shaft first, allowing the pump shaft to extend into the annular ring.

28. Remove the discharge case. This allows access to the top of the impeller shaft for rotating by hand to facilitate stabbing the motor coupling. Assemble motor to the bowl. Observe the position of the cable, leaving the top end of the motor and the relief in the bottom flange of the suction adapter. These should be lined up.

29. Clean the mating faces of the motor and suction adapter. Check carefully to make sure there are not dents or bruises which will misalign the motor to the pump.

30. (IMPORTANT): The axis of the motor and the axis of the bowl should be identical when stabbing coupling and bolting. Any misalignment or sharp radial movement of the motor with respect to the bowl after motor shaft and bowl shaft are in position within the coupling will bend either or both. It is usually advantageous to support the bowl assembly in a rack or vise and lift the motor by its center of gravity by a cable swing or chain. This will allow accurate up and down movement of the motor assembly and slight lateral movements will allow couplings to slip into position with ease. No force should be required to assemble the motor to the bowl.

31. Install the cap screws or nuts, securing them firmly with even pressure all the way around.

32. Check the ease of rotation of the entire assembly, motor and bowl, by rotating the exposed to end of the shaft.

33. Observe the position of the suction adapter sand collar. Push and pull on the top end of the bowl shaft to observe the extremes of the impeller settings. The bottom extreme should occur when the two shafts are butted together and the thrust bearing in the bottom of the motor is restricting any further downward movement. The bottom sand collar should not be all the way down in this position but should be off the housing by 1/3 to 2/3 of the total lateral movement observed previously. There should be some upward movement available to make sure the impellers are not dragging against the top of the bowls.

34. Clean off the impeller shaft and apply a thin coat of AMERICAN TURBINE GREASE.

35. Grease pack the discharge case bearing.

36. Screw or bolt on the discharge case and tighten for final assembly.

37. Replace the suction adapter screen with the stainless steel drive rivets. These rivets are blind rivets and do not need back up. The little pin extending through the top of the rivet swedges out the bottom of the rivet within the drilled hole. Do not hammer on the rivet more than necessary to drive this pin flush with the top of the rivet. Excess hammering will shear the head of the rivet.

38. Secure the motor lead shield. Shield should extend from the top motor end bell all the way to the discharge case or in some cases to the check valve where the check valve is equal or larger in diameter than the pump assembly. The ends of the shield, as well as all the intermediate areas, should rest against some part of the bowl assembly or motor assembly so that external pressure will not allow shield to bend down and cut the cable insulation.

39. Replace coupling hole covers or pipe plugs in suction adapter.

40. Replace all name plates.

41. It is advisable that a record of the pump serial number and motor serial number with the data of the repair and all repairs made along with electrical conditions of the motor, be noted for future reference.

 

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