Flange Loads; Table 3-3. Maximum Allowable Flange Loads; Figure 3-8. Maximum Allowable Flange Loads - Emerson VILTER VSS Installation, Operation And Service Manual

Section 3 • Installation
will avoid costly damage to the equipment due to
freezing.
This information is taken from ASHRAE 15-89 and ANSI/
ASME B31.5. The installing contractor should be thor-
oughly familiar with these codes, as well as any local
codes.
CAUTION
Accumulated liquid in the suction header can damage
the compressor if not drained. Always drain headers
(suction and discharge headers) prior to start-ups.
Failure to comply may result in damage to equipment.
Nozzle Dia. (in.)
4
6
8
10
12
14
5-6 PIPE
DIAMETERS
CUSTOMER SUPPORTS
WHEN CHECK VALVE
CHECK
IS MOUNTED HERE
VALVE
3 – 10
VSS/VSR/VSM/VSH/VSSH Compressor • Installation, Operation and Service Manual • Emerson • 35391S

Table 3-3. Maximum Allowable Flange Loads

Fz (lbf) Fy (lbf)
400 400
600 600
900 900
1200 1200
1500 1500
2000 2000
DISCHARGE
LINE
HANGER
3-4 PIPE
DIAMETERS
SUCTION
LINE
CHECK
VALVE
Y
Z X
X
Z
CUSTOMER
SUPPORT
Y

Figure 3-8. Maximum Allowable Flange Loads

Flange Loads

The ideal load applied to flanges of the compressor unit
is zero. However, it's not practical to expect that no loads
will be applied to unit connections. Thermal, dead, live,
wind & seismic loads must be considered and even toler-
ated. Well supported external piping connected to the
compressor will still result in some loads applying forces
and moments in three axes to unit flanges.
The most important issue is the motor-compressor mis-
alignment caused by external forces (F in lbf) and mo-
ments (M in ft-lbf) imposed by plant piping. In Figure
3-8 and Table 3-3, are the maximum allowable forces
and moments that can be applied to compressor flanges
when the compressor is mounted on an oil separator.
It must be noted that it is necessary to check for com-
pressor shaft movement when the job is complete. In
no case shall the attached piping be allowed to cause
more than 0.002" movement at the compressor shaft.
If more than 0.002" movement is detected the piping
Fx (ft-lbf) Mzz (ft-lbf)
400 300
600 500
900 1000
1200 1200
1500 1500
2000 2000
CUSTOMER SUPPORTS
WHEN CHECK VALVE
IS MOUNTED HERE
5 PIPE
DIAMETERS
Myy (ft-lbf) Mxx (ft-lbf)
300 300
500 500
1000 1000
1200 1200
1500 1500
2000 2000
HANGER
5 PIPE
DISCHARGE
DIAMETERS
LINE
5 PIPE
DIAMETERS
3-4 PIPE
DIAMETERS
CHECK
VALVE
CUSTOMER
SUPPORT
Y
Z X
X
CUSTOMER
SUPPORT
Y
SUCTION
LINE
Z