HPS Rotary Screw Compressor Units
070.700-IOM (MAR 21)
Page 5
Installation
Installation
Foundation
If the HPS rotary screw compressor unit ships are mounted
on a wood skid, remove the skid before unit installation.
Warning
Allow space for servicing the unit as indicate on fac-
tory drawings.
The first requirement of the compressor foundation is that
it must be able to support the weight of the compres
-
sor package including
coolers, oil, and
refrigerant charge.
Screw compressors are capable of converting large quan
-
tits of shaft power into
gas compression in a relatively
small space and a mass is required to effectively dampen
these relatively
high-frequency vibrations.
Firmly anchoring the compressor package to a suitable
foundation by correct application of
grout and eliminating
piping stress imposed on the compressor is the best insur
-
ance for a trouble-free installation. Use only the certified
general arrangement drawings from Frick to determine the
mounting foot locations and to ensure appropriate clear
-
ances around the unit for ease of operation and servicing.
Foundations must be in compliance with local building
codes and materials be of industrial quality.
The floor must be a minimum of 6 in. of
reinforced con-
crete, and you can use housekeeping pads.
Anchor bolts
are required to firmly tie the unit to the floor. After rigging
shim the feet in order to level the unit. Place the shims so
that the feet are positioned roughly 1 in. above the house
-
keeping pad, to allow room for grouting. Work an expan
-
sion-type
epoxy grout under all areas of the base with no
voids and allow to settle with a slight outward slope so oil
and water can run off of the base.
When installing on a steel base, implement the following
guidelines to correctly design the system base:
• Use I-beams in the skid where the screw compressor
are attached to the system base. Run the I-beams par-
allel to the package feet and support the feet for their
full length.
• Weld the compressor unit feet continuously to the sys-
tem base at all points of contact.
• Do not mount the compressor unit on vibration isola-
tors, in order to hold down package vibration levels.
• The customer’s foundation for the system base needs
to fully support the system base under all areas, but
most certainly under the I-beams that support the com-
pressor package.
When installing on the upper floors of buildings, take extra
precautions to prevent normal package vibration from be
-
ing transferred to the building structure. It may be neces
-
sary to use rubber or
spring isolators, or a combination of
both, to prevent the transmission of compressor vibration
directly to the structure. However, this may increase pack-
age vibration levels because the compressor is not in con
-
tact with any damping mass. The mounting and support of
suction and discharge lines is also very important. Rubber
or spring pipe supports may be required to avoid trans
-
ferring resonant energy into the building structure at any
pipe supports close to the compressor package. It is best
to employ a vibration expert in the design of a mounting
arrangement.
In any screw compressor installation, it is necessary to
support suction and discharge lines in pipe hangers (pref
-
erably within 2 ft [0.6 m] of vertical pipe run) so that the
lines won’t move if disconnected from the compressor.
See the following table for allowable flange loads.
Table 2: Allowable flange loads
Nozzle
size
NPS
Moments, ft-lb
(N.m)
Load, lb (N)
Axial
M
R
Vert.
M
C
Lat.
M
L
Axial
P
Vert.
V
C
Lat.
V
L
1
25
(34)
25
(34)
25
(34)
50
(222)
50
(222)
50
(222)
1.25
25
(34)
25
(34)
25
(34)
50
(222)
50
(222)
50
(222)
1.5
50
(68)
40
(54)
40
(54)
100
(445)
75
(334)
75
(334)
2
100
(136)
70
(95)
70
(95)
150
(667)
125
(556)
125
(556)
3
250
(339)
175
(237)
175
(237)
225
(1,001)
250
(1,112)
250
(1,112)
4
400
(542)
200
(271)
200
(271)
300
(1,334)
400
(1,779)
400
(1,779)
5
425
(576)
400
(542)
400
(542)
400
(1,779)
450
(2,002)
450
(2,002)
Consult a licensed architect to determine the foundation
requirements for any large engine or
turbine drive.
When applying screw compressors at high pressures, the
customer must be prepared for
package vibration and
noise higher than the values predicted for normal refrig
-
eration duty. Correct foundations and installation methods
are vital, and even then, sound attenuation or noise cur-
tains may be necessary to reduce noise to desired levels.
For more detailed information on the foundation, refer to
070.210-IB, Screw Compressor Foundations
.
Rigging and handling
Warning
This screw compressor package may be top-heavy.
Use caution in rigging and handling.
To move the unit with rigging using a
crane and spreader
bar, hook into the four lifting eyes on the oil separator.
• If a motor is mounted, make ap propriate adjustments in
the lifting point to compensate for motor weight.
•
Make adjustments to the lifting point for any additions
to the standard package, such as an external oil cooler,
because this affects the center of balance.
Refer to supplied engineering drawings to determine the
package center of gravity.
You can move the unit with a
forklift by forking
under the
skid
, or you can skid into place with pinch bars by pushing
against the skid.