GENERAL TORQUE VALUES - Continued
O-Ring Face Seal Fittings With Metric Hex Nut and Stud End For High-Pressure Service Recommendations
Inspect fitting and connector sealing surfaces and the O-rings. They must be free of dirt, scratches, nicks, and
burrs. O-ring must be free of dirt, cuts, cracks, swelling or flatten condition.
Back the stud end hex nut off as far as possible. Push backup washer towards the nut to fully expose the turn
down section. Washer must fit turned down section and not be too loose.
Lubricate O-rings using a thin film of clean oil to hold O-ring in place. Refer to LO 5-3805-294-13.
Install O-ring into groove making sure it is seated at the bottom. Excess oil will prevent seating of O-ring and
cause it to pop out.
To protect an O-ring from threads, wrap electrical tape over the threads. Slide O-ring over the tape into the
turned down section. Remove the tape.
Turn fitting into the boss by hand until face of nut or washer squeezes the O-ring into the seat and contacts
face of boss. Loosen adjustable fittings no more than one turn for alignment.
Hold connections together while tightening nut to ensure O-ring remains in place.
Tighten fitting or nut to torque value shown. Use a second wrench to hold the fitting in position or to keep hose
from twisting while tightening nut.
Figure 20 shows the O-Ring Face Seal Fitting with Metric Hex Nut and Stud End for High-Pressure Service.
Bulkhead Union and Nut
90 Degree Adjustable Stud Elbow
90 Degree Swivel Elbow
External Hex Stud End Plug
O-Ring Face Seal Fitting with Metric Hex Nut and Stud End for High-Pressure Service.