Sinclair ASCU-12A, Service Manual

Page: 79 / 202

U-MATCH AIR CONDITIONERS INSTALLATION
77
‹ Tighten the flare nut with a torque spanner until the torque spanner makes a click, as shown
in Figure 3-1-1. Moment needed for tightening a nut is shown in Tab. 3-1-1.
Figure 3-1-2
Form 3-1-1 the tightening torque needed for tightening nut
Pipe diameter Tightening torque
1/4 ＂
15-30 (N·m)
3/8 ＂
35-40 (N·m)
5/8 ＂ 60-65 (N·m)
1/2 ＂
45-50 (N·m)
3/4
＂
70-75 N·m)
‹ Curvature of piping shall not be too small, or otherwise piping may be broken. So installation
personnel should use a pipe bender to bend pipes.
‹ Upward or longitudinal welding joint method is usually applied to the welding of pipelines.
The welding method that mouth of pipe is downward (face-down welding) should be avoided
as far as possible, because such method is prone to welding defects and even would cause
leakage, as shown in Figure 3-1-3.
Figure 3-1-3
‹
Uninsulated connecting pipes and connectors should be packed with sponge and tied with
plastic adhesive tapes.