Maintenance of LC Vertical Long Shaft Pump
LC type vertical long shaft pump should be disassembled and repaired when necessary (vibration, noise, bearing temperature exceeding allowable value, flow rate, head significantly decreased, etc.). For continuous operation of vertical long-axis pumps, regular inspection should be carried out every year.
(1) Prepare spare parts in advance for the maintenance of vertical long-axis pumps.
(2) Disassemble the vertical long-axis pump according to the reverse assembly sequence. After disassembly, the rust spots on the parts should be removed and then re-painted.
(3)Check the clearance between the impeller and seal ring. Please refere to below chart.
Norminal diameter | ～125 | ～160 | ～200 | ～250 | ～315 | ～400 | ～500 | ～630 |
The maximum clearance allowed |
1.1～1.8 |
1.2～2.0 |
1.3～ 2.2 |
1.5～ 2.5 |
1.7～ 2.8 |
1.9～ 3.1 |
2.1～ 3.5 |
2.4～ 4.0 |
Check the abrasion of guide bearing. Please see below table for reference.
Nominal diameter | ～60 | ～80 | ～100 | ～120 | ～140 | ～160 | ～180 |
The maximum clearance allowed |
0.4～0.8 |
0.5～0.9 |
0.6～1.0 |
0.7～1.2 |
0.8～1.3 |
0.9～1.4 |
1.0～1.5 |
（4） Check the abrasion of the shaft sleeve and the packing sleeve. If the abrased slot’s diameter reaches 1～2mm, please replace it.
（5） Check the abrasion of the impeller and impeller body.
（6） Replace the sealing parts , like packing seal, O-ring seal and paper washer.
（7） Assemble the pump in order and rotate the pump rotors which should run smoothly.
Attention: The safety procedure and regulations should be followed throughout the inspection. Before any inspection, please do as below: 1.Cut the motor power off and all the instruments. 2.Shut the outlet and inlet valve. 3. Cut off cooling water. |
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