A first relief valve chamber (3) of a main relief valve (10) and a second relief valve chamber (7) of an auxiliary relief valve (11) are provided in series in a valve case 1. The first relief valve chamber (3) includes a valve seat chamber (4) at the right and a valve chamber (5) at the left. A first valve member (30) in the valve chamber (5) is biased toward a valve seat member (18) in the valve seat chamber (4) by a first relief spring (40). A second valve member (48) in the second relief valve chamber (7) is biased toward a second valve seat (47) by a second relief spring (50).

A first relief valve chamber (3) of a main relief valve (10) and a second relief valve chamber (7) of an auxiliary relief valve (11) are provided in series in a valve case 1. The first relief valve chamber (3) includes a valve seat chamber (4) at the right and a valve chamber (5) at the left. A first valve member (30) in the valve chamber (5) is biased toward a valve seat member (18) in the valve seat chamber (4) by a first relief spring (40). A second valve member (48) in the second relief valve chamber (7) is biased toward a second valve seat (47) by a second relief spring (50).

An aircraft gas transport system including a high pressure gas supply line having a supply valve, and an equilibrium gas line joined at junctions with the high pressure gas supply line upstream and downstream from the supply valve, and in flow communication with the high pressure gas supply line, the equilibrium gas line having an equilibrium valve and a flow restrictor, the equilibrium valve having an exit orifice and the flow restrictor being offset from the exit orifice of the equilibrium valve.

An aircraft gas transport system including a high pressure gas supply line having a supply valve, and an equilibrium gas line joined at junctions with the high pressure gas supply line upstream and downstream from the supply valve, and in flow communication with the high pressure gas supply line, the equilibrium gas line having an equilibrium valve and a flow restrictor, the equilibrium valve having an exit orifice and the flow restrictor being offset from the exit orifice of the equilibrium valve.

Provided are a control valve, a derricking cylinder and a working method thereof, and an aerial work platform, relating to the field of aerial work. The control valve of the derricking cylinder includes a first balance valve provided on the oil circuit between the first port G and the second port F, and a second balance valve provided on the oil circuit between the third port H and the fourth port E; and a switch valve in series with the first balance valve is further provided on the oil circuit between the first port G and the second port F.

Provided are a control valve, a derricking cylinder and a working method thereof, and an aerial work platform, relating to the field of aerial work. The control valve of the derricking cylinder includes a first balance valve provided on the oil circuit between the first port G and the second port F, and a second balance valve provided on the oil circuit between the third port H and the fourth port E; and a switch valve in series with the first balance valve is further provided on the oil circuit between the first port G and the second port F.

A servo valve comprises a valve housing, a cavity formed in the valve housing and defining a longitudinal axis (X), and a member disposed in the cavity and axially-moveable therein, wherein the member comprises a portion with first and second cylindrical sections having a first diameter (R1, R2), a central section located between the first and second cylindrical sections and having a second diameter (R3), and first and second frusto-conical sections connecting the first and second sections to the central section and forming respective first and second frusto-conical surfaces. A plurality of ports, each form a fluid passage through the valve housing and have first and second nozzles with first and second nozzle openings.

A first relief valve chamber (3) of a main relief valve (10) and a second relief valve chamber (7) of an auxiliary relief valve (11) are provided in series in a valve case 1. The first relief valve chamber (3) includes a valve seat chamber (4) at the right and a valve chamber (5) at the left. A first valve member (30) in the valve chamber (5) is biased toward a valve seat member (18) in the valve seat chamber (4) by a first relief spring (40). A second valve member (48) in the second relief valve chamber (7) is biased toward a second valve seat (47) by a second relief spring (50).

A first relief valve chamber (3) of a main relief valve (10) and a second relief valve chamber (7) of an auxiliary relief valve (11) are provided in series in a valve case 1. The first relief valve chamber (3) includes a valve seat chamber (4) at the right and a valve chamber (5) at the left. A first valve member (30) in the valve chamber (5) is biased toward a valve seat member (18) in the valve seat chamber (4) by a first relief spring (40). A second valve member (48) in the second relief valve chamber (7) is biased toward a second valve seat (47) by a second relief spring (50).

A valve body with an integral bypass includes a primary valve body portion defining a primary internal surface, the primary internal surface defining a primary bore extending through the primary valve body portion from a primary upstream end to a primary downstream end; and the bypass seamlessly integrated with the primary valve body portion, the bypass defining a bypass internal surface, the bypass internal surface defining a bypass bore, the bypass bore comprising a bypass upstream bore and a bypass downstream bore, the bypass upstream bore extending through the primary upstream end of the primary valve body portion, the bypass downstream bore extending through the primary downstream end of the primary valve body portion, the bypass internal surface seamlessly intersecting the primary internal surface at the primary upstream end and the primary downstream end.