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Subject to change without prior notice
INSTALLATION OPERATION AND MAINTENANCE INSTRUCTIONS
VERTICAL TURBINE PUMP - NVT SERIES
Ref. No. NVT-IOM/2020/V.01
8. DISMANTLING AND REASSEMBLY
8.1. General
Before dismantling, make sure the pump set is disconnected from the power supply and cannot be switched on
accidentally. The discharge shutoff valves must be closed.
»
Observe how long it takes the engine to crank and once started how long it takes to reach the running speed.
»
Record the pump discharge pressures.
»
Check the pump packing glands to ensure proper tightness and adequate lubrication (should be slow drips –
approximately
1
drop per second – adjust glands if necessary with pump off).
»
Check the vertical turbine pump, right angle gear drive, universal joint drive shaft and diesel engine for any
unusual noise or vibration.
»
Check the pump stuffing box packing gland, and discharge head for any signs of overheating (stuffing box
should be warm to the touch – discharge head should be cool to the touch).
»
Verify proper operation of pressure relief valve.
»
Check the heat exchanger for cooling water flow.
»
Record cooling system temperature.
»
Check engine speed and record rpm.
»
Check oil pressure (should match manufacturer’s recommendation) and record.
»
Record current reading (should be +
2
to +
5
amps after
5
minutes of running time).
»
Verify that engine will start off of both sets of batteries.
»
Verify operation of all supervisory signals (i.e., pump running, controller in automatic mode, etc.).
»
Verify all valves are back to normal position.
»
Verify that pump is left in the automatic start mode upon completion of each test.
8.2. Gland Packing Replacement
When the gland leaks excessively and adjustment has no effect then it is time to replace the gland packing.
1.
Remove the guarding, on discharge head, surrounding the stuffing box.
2.
Remove the gland retaining nuts and withdraw the gland clear of the stuffing box.
3.
Carefully remove the old packing using a packing hook. (see Fig. No.
20
-a).
4.
Remove lantern ring by inserting a wire hook in the slots of the ring and pull it from packing box.
5.
Remove all traces of the old packing material and clean the stuffing box thoroughly.
6.
Gland packing is normally supplied as continuous coil or rope. The requisite number of rings of the required
length must be cut from this coil / rope.
7.
Tightly wrap one end of the packing around the shaft sealing sleeve like one coil of a coil spring (see Fig. No.
20
-b).
8.
Mark the coil with a sharp knife at the point where the gland packing rope touches the end wrapped on the
sleeve. The point marked should be such that the ends of the ring obtained by cutting at that point will meet
each other without overlapping (see Fig. No.
20
-c).
