O-Ring Face Seal Fittings
SMCS Code: 7553
O-ring face seal fittings.
(1) O-ring face seal fitting. (2) O-ring groove. (3) Nut for the O-ring
face seal. (4) O-ring seal. (5) Straight thread O-ring fitting.
Ferrous Straight Thread O-Ring Fitting
9/16 - 18
25 ± 3 Nm (18 ± 2 lb-ft)
11/16 - 16
37 ± 4 Nm (27 ± 3 lb-ft)
13/16 - 16
54 ± 5 Nm (40 ± 4 lb-ft)
1 - 14
86 ± 8 Nm (65 ± 6 lb-ft)
1 13/16 - 12
125 ± 15 N m (90 ± 11 lb-ft)
1 7/16 - 12
165 ± 15 N m (120 ± 11 lb-ft)
1 11/16 - 12
200 ± 20 N m (150 ± 15 lb-ft)
2 - 12
225 ± 20 N m (165 ± 15 lb-ft)
SMCS Code: 7553
NOTE: The tightening sequence of the
assembly or hose assembly to the
machine is very critical to the
proper function of the machine.
The sealing surfaces of the tube
should be secured squarely. The
sealing surfaces of the tube
valve, cylinder, hydraulic motor,
etc). Perform this procedure prior
to the final tightening of any
clamps or clips that are used in
order to fasten the tube assembly
or the hose assembly to the
Installation of the Hydraulic Line
For a metal tube to hose installation, install the tube and
tighten all bolts finger tight at the rigid end.
Install the hose and tighten all bolts finger tight.
Put the hose in a position so that the hose does not
make contact with the machine or with another hose.
Tighten the bolts on both connections to the specified
Start the engine.
Move the implement control levers to all of the positions.
Look at the hose during movement of the implement.
Ensure that the hose is not in contact with the machine
or other hoses. Shut off the engine.
If necessary, put the hose in a new position so that the
hose will not make contact when the machine
implement is moved.
Assembly of the Fittings with Straight Threads and
This type of fitting is used in many applications. The tube end
of the fitting will be different in design so that the fitting can be
used in many different applications. However, the same
installation procedure for the fitting can be used. If the tube
end of the fitting body and the illustration (elbow or straight
body) match, it is necessary to assemble the sleeve on the
tube before connecting the tube to the end.