Pump Exchange Procedure
VT Column-mounted Pump Exchange Procedure
This having been done, the following procedure should be simple and effective.
1) Turn the hand-off-automatic (HOA) switch for the pump to be exchanged to the off position.
2) Carefully, as there is still 3 phase power in both the panel, remove the wires from the bottom of the contactor. Label each wire T1, T2 & T3 as it is removed. Alternatively, the main power can be disconnected to perform this step with a greater degree of safety.
3) Close the inlet and outlet isolation valves on the pump to be removed.
4) Remove the cover from the top of the motor on the pump to be removed.
5) Remove the motor adjusting nut lock screws and remove the adjusting nut turning it clockwise until it is off of the motor head shaft.
6) Remove the gib key from the Shaft/coupling assembly.
7) Using two pipe (Stilson) wrenches hold the motor head shaft/pump shaft coupling with one wrench and use the other to turn the shaft clockwise to remove it from the coupling.
**Note: If this step doesn’t work, the motor can be removed if care is taken to lift the motor straight upwards of the shaft. If not performed slowly and correctly, the pump head shaft can get damaged.
Remove the bolts connecting the motor to the pump discharge head.
9) Lift the motor off of the pump discharge head using the lugs on the motor. Set the motor down the on the pump skid. The motor power leads do not have to be disconnected as there is sufficient slack to allow moving the motor off to one side.
10) Loosen and remove the bolts holding the discharge head to the skid.
11) Loosen and remove the bolts and nuts securing the victaulic coupling downstream of the pump check valve.
12) Lift the pump out of the pump vault
13) Remove the strainer from the pump and lower the pump on to a wooden skid so that the pump is supported horizontally.
14) Remove the coupling from the pump shaft. Use two pipe wrenches but attempt to avoid damaging the pump shaft. Use a piece of leather to minimize shaft damage. Any damage must be corrected using files and emery cloth before further disassembly.
15) Loosen the nuts retaining the bronze packing gland plate.
16) Remove the four bolts retaining the pump stuffing box and remove the stuffing box being careful not to lose or damage the o-ring underneath.
17) The discharge head must now be removed from the pump column by rotating it counter-clockwise. The head must be supported during this time while rotating to avoid resting on the pump shaft. Once loose, remove the head over the shaft.
18) Using two large chain wrenches, remove each section of column pipe in sequence from the top to the bottom. Hold the column pipe coupling with one wrench while rotating each piece of pipe.
19) Remove each lineshaft coupling tagging the coupling to assume it will be replaced in the proper order.
20) There is a spider bearing between each pipe section. Remove them in order and tag each one so as to assume they will be replaced in the proper location.
21) Continue removing each pipe and shaft section until all that remains is the bowl assembly and its shaft which will extend less than .5 meters above the pump discharge connection.
22) Remove the protective pipe section from the new pump and reverse the disassembly procedure assuring that each component (spider bearing, shaft section, pipe section and coupling) is replaced in its original location and is securely fastened. Remember the pipe threads are right hand and the shaft and its couplings are left hand.
23) Once assembled back to its original length, carefully place the discharge head over the shaft and screw it on to the pump column.
24) Replace the stuffing box taking care to properly locate its o-ring.
25) Replace the pump shaft coupling.
26) Lift the new pump, preferably with a sling arrangement that isolates stress on the length of the column.
27) Once vertical, install the strainer previously removed from the original pump.
28) Lower the pump into the open location on the pump skid and reverse the removal procedure being sure to tighten the Vitaulic coupling securely.
29) Replace the motor on top of the pump discharge head and bolt into position.
30) Install the motor headshaft into the pump shaft coupling.
31) Assume that impellers are on the bottom of the bowls by tapping with a hammer and a piece of wood on the inserted motor headshaft.
32) Install Gib key and impeller adjusting nut.
33) Once the nut butts up against the motor coupling, turn the nut a further two turns counterclockwise.
34) Insert the adjusting nut locking screws.
35) The motor and pump assembly should be able to be able to be turned by hand in a counter clockwise direction.
36) Replace the motor top cover.
37) Carefully replace the motor leads previously discounted in the temporary panel.
38) Return the isolation valves on the pump inlet and discharge to a fully open position.
Place the HOA switch on the control panel to the “Auto” position.
