WinGD X72 - Page 228

Operation2751−1/A1
Winterthur Gas & Diesel Ltd.
4/ 5
Key to Fig. 2: Exhaust Valve and Leakage Oil Drain
1 Damper 16 Valve spindle
2 Top housing 17 Leakage oil collection space
3 Orifice 18 Hydraulic oil connection
4 Outer piston 19 Valve stroke sensor
5 Inner piston 20 Non-return valve
6 Thrust piece
7 Piston guide
8 Housing AI Air inlet to air spring
9 Air spring piston IB Inlet bore (to air spring)
10 Cup spring OB Oil bath
11 Guide bush AS Air spring
12 Valve cage LD Leakage oil drain
13 Cylinder cover OS Oil supply (to valve guide)
14 Valve seat AS Air spring
15 Rotation wing HO Hydraulic oil inlet
2. Function
2.1 Open
When the piston in the valve control unit (VCU) operates, hydraulic oil (HO) flows
through the connection (18, Fig. 2) into the top housing (2). The outer piston (4) and
the inner piston (5) move down.
The air spring piston (9), which is attached to the valve spindle (16), moves down
against the pressure in the air spring (AS) and the exhaust valve opens. The force of
the exhaust gas on the rotation wing (15) turns the valve spindle.
2.2 Close
When the hydraulic oil pressure from the VCU decreases (i.e. when the control rod in
the VCU opens the related relief bores) the pressure in the air spring (AS) pushes the
air spring piston (9) up.
The valve spindle (16) then pushes the inner piston (5) and the outer piston (4) up
and the exhaust valve closes. The hydraulic oil in the top housing (2) flows back to
the VCU.
2.3 Hydraulic System
Hydraulic oil and air in the system flow continuously from the top housing (2), outer
piston (4) and inner piston (5) into the leakage oil collection space (17). This leakage
oil / air then drains though the leakage oil drain (LD).
The hydraulic oil that flows through the internal bores of the VCU continuously keeps
the correct oil quantity in the hydraulic system.
2.4 Air Supply to Air Spring
Compressed air flows into the air inlet connection (AI) and through the non-return
valve (20) to the inlet bore (IB). The compressed air then flows into the air spring
(AS).
When the exhaust valve opens the air spring piston (9) moves down, which
compresses the air in the air spring (AS). Some of the compressed air flows back
through the inlet bore (IB). After the exhaust valve closes, compressed air flows again
into the air spring (AS).
Exhaust Valve
2014