4-13. 6-NFR DISTRIBUTING VALVE (cont)
Apply one drop triple valve oil to slide valve seat in bushing and one drop to face of slide valve (18). Distribute
over entire surface.
Install equalizing piston assembly (14) in body (52). Check that bead of diaphragm (23) is posi
tioned in recess of
Install gaskets (13) and (12) and equalizing piston cover (11) and secure with four bolts (10).
Assemble check valve and carrier assembly (5) by the following:
Install check valve (8) on carrier (9) and secure with pin (7).
Install O-ring (6) on carrier (9).
Install check valve and carrier assembly (5) in body (52). Install spring (4) in carrier (9).
Install gasket (3) and top cover (2) and secure with three bolts (1).
Test the 6-NFR distributing valve in accordance with New York Air Brake Company Test Specification NYT-460.
During charging and release, the 6-FNR distributing valve functions as follows:
Brake pipe air flows first to the outer face of the equalizing piston diaphragm, forcing the piston and
slide valve to release position.
Air in brake pipe flows through charging choke and equalizing slide valve to the pressure chamber,
charging it to brake pipe pressure.
In this position, equalizing slide valve connects application chamber through release port No. 4 to
Application cylinder on the outer face of application piston is exhausted via passage 2a, through No.
24-A double check valve, passages 26, 2, then 4 in the distributing valve, to exhaust.
The release spring holds application piston in release position against application cylinder cover.
The inner end of application piston, which is machined to form the exhaust valve seat, is moved away
from the rubber supply and exhaust valve to vent the brake cylinder passage.