Emerson Liebert SRC18 - Tightening Flare Nuts; Figure 5-2 Flared-Connection Dimensions; Figure 5-3 Tightening the Flare Nuts; Table 5-1 Flared-Connection Dimensions

Piping
37 Liebert
®
SRC™ User Manual
4. Carefully inspect the flared pipe end.
• Compare the geometry with Figure 5-1 and the dimensions detailed in Figure 5-2 and Table 5-1.
Figure 5-2 Flared-connection dimensions
5.1.2 Tightening Flare Nuts
1. When connecting the flare nuts, coat the flare (inside and outside) with polyvinyl ether (PVE)
refrigeration oil only.
2. Initially, hand tighten the flare nuts using 3 or 4 turns.
3. Finishing tightening the flare nuts using both a torque wrench and a backup wrench as shown in
Figure 5-3.
Figure 5-3 Tightening the flare nuts
Table 5-1 Flared-connection dimensions
Pipe “A” Thickness
Vapor (in. O.D.) Liquid (in. O.D.) Vapor (in.) Liquid (in.) Vapor (in.) Liquid (in.)
1/2 1/4 1/8 1/16 1/8 1/8
5/8 3/8 1/8 1/16 1/16 1/8
NOTE
Do not use polyolyester (POE) or any other type of mineral oil as a thread
lubricant. These lubricants are not compatible with PVE oil used in this system
and create oil sludge leading to equipment damage and system malfunction.
Table 5-2 Tightening torque for flare nuts
Pipe size (in. O.D.) Tightening torque (ft-lbs) Width of flare (A [in.])
1/4∅
13.9 – 18 1/8
3/8∅
24.5 – 30.3 1/8
1/2∅
39.7 – 47.7 1/8
5/8∅
45.5 – 59.2 1/16
90°
2
45°
2
A
R=0.4~0.8
Union