Daikin SkyAir Service Manual page 270

SiBE28-804
Caution for flare
connections
Appendix
Refer to below table for correct flare dimensions and tightening torques. Too high tightening
force may cause refrigerant leak because of flare cracking:
Flare nut
Piping size
tightening torque
14.2~17.2 N·m
φ 6.4
(144~176 kgf·cm)
32.7~39.9 N·m
φ 9.5
(333~407 kgf·cm)
49.5~60.3 N·m
φ 12.7
(504~616 kgf·cm)
61.8~75.4 N·m
φ 15.9
(630~770 kgf·cm)
97.2~118.6 N·m
φ 19.1
(989.8~1208 kgf·cm)
When connecting the flare nut, apply refrigerating machine oil to the flare (inside and
outside) and first screw the nut 3 or 4 turns by hand. Coat the indicated surfaces using ether
or ester oil:
After completing the installation, carry out an inspection of the piping connections by
pressure test using nitrogen.
A dimensions for
processing flares (mm)
8.7~9.1
12.8~13.2
16.2~16.6
19.3~19.7
23.6~24.0
Piping Diagrams
Flare shape
90° ±0.5
A
R=0.4~0.8
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