48 l
Installation, operation and maintenance manual – Squirrel cage motor – W Line - Horizontal and vertical 11239449
8.3
AIR-GAP MEASUREMENT
After disassembling and assembling the motor, it is
necessary to measure the air gap in order to check the
concentricity between rotor and stator.
The difference between the air-gap measured in two
points diametrically opposed must be less than 10% of
the average air gap.
8.4
TIGHTENING TORQUE
Table 8.1 and Table 8.2 shows the tightening torques of
the screws recommended for assembling the motor.
Table 8.1: Screw tightening torque for metal/metal parts
Material /
Resistance
class
Carbon Steel /
8.8 or above
Stainless steel /
A2 – 70 or above
% Yield
Strength
60%
70%
Lubricant
Dry
Molycote
1000
Dry
Molycote
1000
Diam
Pitch
(mm)
Screws tightening torque (Nm)
M3 0,5 1,2 0,8 1 0,69
M4 0,7
2,7 1,8 2,4 1,6
M5 0,8
5,4 3,6 4,8 3,2
M6 1 9,3 6,3 8,2 5,5
M8 1,25 22,4 15
20
13
M10
1,5
44 30 39 26
M12
1,75
77 52 67 45
M14 2 123 82 107 72
M16 2 188 126 165 110
M18
2,5 263 176 230 154
M20
2,5 368 246 322 215
M22
2,5 500 332 437 290
M24 3 637 425 557 372
M27 3 926 615 810 538
M30 3,5 1260 838 1102 734
M33 3,5 1704 1130
1490 990
M36 4 2195 1459
1920 1277
M42 4,5 3507 2328
3070 2037
M48 5 5258 3488
4600 3052
Table 8.2: Screw tightening torque for metal/isolated parts
Material /
Resistance
class
Carbon Steel /
8.8 or above
Stainless steel /
A2 – 70 or above
% Yield
Strength
33%
33%
Lubricant
Dry
Molycote
1000
Dry
Molycote
1000
Diam
Pitch
(mm)
Screws tightening torque (Nm)
M3 0,5 0,6 0,5 0,48 0,32
M4 0,7 1,5 1 1,1 0,76
M5 0,8 3
2 2,2 1,5
M6 1 5,2 3,4 3,8 2,6
M8 1,25 12,3 8,3 9,2 6,2
M10 1,5 24
16 18,2 12,2
M12
1,75
42 28 32 21
M14
2 68 45 51 34
M16
2
104 69 78 52
M18 2,5 145 98 108 72
M20
2,5 202 135 152 101
M22
2,5 274 183 206 137
M24 3 350 233 263 175
M27 3 510 338 382 254
M30
3,5 693 461 520 346
M33
3,5 937 622 703 466
M36 4 1207 802 905 602
M42 4,5 1929 1280
1447 960
M48 5 2892
1918
2170
1440
NOTE
The resistance class is normally indicated on
the head of the hex bolts.
8.5
SPARE PARTS
When ordering spare parts, inform the motor type and
serial number, according to the motor nameplate.
WEG recommends keeping in stock the following spare
parts:
Table 8.3: Spare parts list
Spare parts
•
Recommended
▲
Highly Recommended
Temperature sensor for front and rear bearing
▲
Space heater
▲
Grounding Brush
▲
Lubricant for bearings
▲
Vibration sensor for front and rear bearing (if applicable)
•
Vibration signal converter for front and rear bearing (if
applicable)
•
Water temperature sensor (if applicable)
•
Set of water leakage sensor (if applicable)
•
Repeater relay for water leak sensor (if applicable)
•
Water regulating valve (if applicable)
•
Front and rear bearing
▲
Teflon seal
▲
Internal bearing cap
•
External bearing cap
•
Grease valve
•
Ring with labyrinth
•
Cylindrical pressure spring
•
Protective ring against water ingress
•
The spare parts must be stored in a clean, dry and well-
ventilated environment and, if possible, at constant
temperature.
