Flange Loads; Table 3-1. Maximum Allowable Flange Loads; Figure 3-10. Maximum Allowable Flange Loads - Emerson Vilter VSS Installation, Operation & Maintenance Manual

Section 3 • Installation
may be drained from the system after the plant has
been shut down in cold weather. These precautions
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
IS MOUNTED HERE CHECK
VALVE
VSS/VSM/VSH/VSSH • Installation, Operation and Maintenance Manual • Emerson • 35391SD

Table 3-1. 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
CUSTOMER
SUPPORT
Y

Figure 3-10. 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
3-10 and Table 3-1, 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
Fx (ft-lbf) Mzz (ft-lbf)
400
600
900 1000
1200 1200
1500 1500
2000 2000
CUSTOMER SUPPORTS
WHEN CHECK VALVE
IS MOUNTED HERE
5 PIPE
DIAMETERS
Z
Myy (ft-lbf)
300 300
500 500
1000
1200
1500
2000
HANGER
5 PIPE
DIAMETERS
5 PIPE
DIAMETERS
CHECK
VALVE
CUSTOMER
SUPPORT
Y
Z
X
Y
Mxx (ft-lbf)
300
500
1000
1200
1500
2000
DISCHARGE
LINE
3-4 PIPE
DIAMETERS
SUCTION
LINE
X
Z
CUSTOMER
SUPPORT
3 – 13