Johnson Controls SAB 355 - Piping Connections

Engineering manual - SAB 355 Screw compressor unit (including ATEX)
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004100 en 2020.10
Installation instructions
3. Mount bolts between the flexible discs and the coupling flange of the motor. Tighten all
bolts to the torque indicated in Table 31.
4. Check distance C.
5. Once the coupling alignment has been carried out correctly, fit the outer shell of the cou-
pling guard on the adaptor plate which is secured on the compressor shaft seal cover.
6. Push the inner shell, which is placed inside the outer shell, so far towards the driving mo-
tor that access to the rotating parts is made impossible. See Fig. 81.
7. Recheck the coupling when the compressor is still warm from operation and with pressure
on piping connections.
Important: The alignment must be checked as warm alignment after 1-2 hours of run-
ning and before VibraGuard measuring is performed.
Set screw
thread size
Torque
in-lb
Torque
ft-lb
Torque
Nm
1
/
4
- 20
66 6 7
1
/
4
- 28
76 6 9
5
/
16
- 18
132 11 15
5
/
16
- 24
144 12 16
3
/
8
- 16
240 20 27
3
/
8
- 24
276 23 31
½ - 13 600 50 68
½ - 20 660 55 75
Table 31: Set screw tightening torque
Fig. 81
7.30 Piping connections
To avoid transmitting stress from piping connections between unit and plant, pipes must be laid
so as not to generate compressive stresses or tensile strains in the event of expansions or con-
tractions due to temperature changes. Steel pipes expand approx. 1 mm per metre per 100°C.
Johnson Controls Denmark recommends the pipe layout shown in example 2 of the sketch,
Fig. 82. Example 1 illustrates a pipe layout which is too rigid.