McQuay Skyline IM 777-1, Руководство по установке и обслуживанию

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McQuay IM 777-1 15
Operation Guidelines
7
Check alignment of fan and motor sheaves and belt tension.
Adjust if necessary. Check tightness of sheave setscrews
and/or capscrews. See Figure 35 and Figure 36 on page 24.
8
Leak test the thermal system to verify that connections are
tight.
9
Check that the condensate drain is trapped.
10
Rotate the shaft by hand to be sure it is free.
Fan startup:
Start and run fan. Observe the rotation. If the fan operates
backward, reverse two legs of the three-phase supply power.
Note – Variable pitch fan drives usually are provided for operation
in the mid-speed adjustment range. However, the drives
usually ship with the adjustment opened up for minimum
fan speed. Adjust the drives for the proper airflow. See
“Fan Drive Adjustments” on page 20.
After the first 48 hours of operation:
1
Disconnect and lock electrical power source.
2
Check tightness of all bearing, wheel, and sheave setscrews
(or capscrews). See Table 6.
3
Recheck belt tension and adjust if necessary. Belts
tensioned sufficiently to slip one to two seconds at startup
will perform satisfactorily, extending life and reducing
vibration. If retensioning is necessary, be certain to retain
sheave alignment.
Fan Wheel Alignment
Figure 23: Wheel-to-inlet funnel relationship—airfoil type f
an wheels (housed)
Notes:
1. To obtain rated air performance, dimensional relationship must be held.
2. To obtain dimension A, loosen setscrews in wheel hub(s), shifting wheel(s)
axially as needed, and retightening setscrews.
3. To obtain dimension B, loosen screw and washer fasteners around
periphery of funnel(s), shifting funnel radially as required, and re-torquing
fasteners.
Figure 24: Wheel-to-inlet funnel relationship—forward
curved type fan wheels
Notes:
1. To obtain rated air performance, dimensional relationship must be held.
2. Adjust dimension C by loosening wheel hub set screws, shifting wheel(s)
axially as needed, and retightening set screws.
Table 2: Wheel-to-inlet funnel relationship—airfoil type
Airfoil
Unit sizes 003 to 035 Unit sizes 040 to 090
Dia.
A
(in)
A
(mm)
B
(in)
B
(mm)
Dia.
A
(in)
A
(mm)
A
(in)
B
(mm)
13.22 4.56 116 0.21 5.33 20.00 7.19 183 0.31 7.87
14.56 5.06 129 0.21 5.33 22.25 7.69 195 0.33 8.38
16.18 5.62 143 0.21 5.33 24.50 8.56 217 0.31 7.87
17.69 6.90 175 0.22 5.59 27.00 9.47 241 0.63 16.00
21.56 7.59 193 0.24 6.10 30.00 10.47 266 0.39 9.91
24.00 8.45 215 0.23 5.84 33.00 11.75 298 0.38 9.65
36.50 12.78 325 0.38 9.65
40.25 14.31 363 0.50 12.70
A A
B
E q u a l s p a c i n g
a l l a r o u n d
Table 3: Wheel-to-inlet funnel relationship—forward curved
type fan wheels
Forward curved
Unit sizes 003 to 035 Unit sizes 040 to 090
Diameter \(in) C (in)
C
(mm)
Diameter (in) C (in)
C
(mm)
9 x 4 0.25 6.35 20 (Class 1 & 2) 0.24 6.10
9 x 7 0.13 3.30 22.38 (Class 1 & 2) 0.41 10.41
9 x 9 0.25 6.35 25 (Class 1 & 2) 0.47 11.94
10 0.22 5.59 27.62 (Class 1 & 2) 0.47 11.94
12 0.35 8.89 30 (Class 1 & 2) 0.47 11.94
15 0.44 11.18 33 (Class 1 & 2) 0.50 12.70
18 0.25 6.35 36 (Class 1 & 2) 0.75 19.05
20 (Class 1 & 2) 0.73 8.54
22 1/2 (Class 1 & 2) 0.59 14.99
24 1/2 (Class 1 & 2) 0.56 14.22
I n l e t
F u n n e l
W h e e l
C
C
I n l e t
F u n n e l