1 12 mechanical, numerical control professional "hydraulic and pneumatic drive" review questions and some reference answers (second edition) A single choice 1.
In the liquid flow, the phenomenon that a large amount of bubbles are generated due to the pressure at a point lower than the air separation pressure is called (C) A, laminar flow B, hydraulic impact C, hole phenomenon D, turbulent flow 2.
The working pressure in the hydraulic drive depends on (A) A, external load B, flow rate C, speed D, flow rate and speed 3.
The hydraulic elements that convert mechanical energy input by the engine into pressure energy of the liquid are (A) A, a hydraulic pump B, a hydraulic motor C, a hydraulic cylinder D, and a control valve 4.
How much hydraulic pump output fluid, mainly depends on (C) A, rated pressure B, load C, seal the size of the working chamber volume change D, the motor power 5.
The central function of the directional valve can be achieved when the system unloading is (A) A, MB, PC, OD, Y6.
Commonly used solenoid valve is to control the fluid (B) A, flow B, direction C, flow and direction D, pressure 7.
If the differential hydraulic cylinder reciprocates at the same speed, the piston area should be (A) A, l times B, 2 times C, 2 times D, 3 times the area of ??the piston rod.
Large flow system, the main valve should be used to change the direction valve (B) A, electromagnetic B, electro-hydraulic C, manual D, motor 9.
In the hydraulic system diagram, the oil line connected to the three-position valve should generally be drawn at the position (C) A of the reversing valve, left panel B, right panel C, center panel D,
The main ways to improve the working pressure of the gear oil pump are to reduce the axial leakage of the gear oil pump and cause the axial leakage of the gear oil pump mainly because (D) A, the gap B at the gear meshing line, the inner wall of the pump body (hole) The gap between the circle C, the gap between the drive shaft and the bearing D, the gap between both sides of the gear and the end cap 11.
The main reason that the volumetric efficiency of the hydraulic pump is declining is (D) A, the working pressure B, the internal friction C, the variation of working chamber volume D, and the internal leakage 2 12.
Pressure valve to maintain work (B) A, the same import pressure B, the same outlet pressure C, import and export pressure will not change D, import and export pressure has changed 13.
Double acting rod piston hydraulic cylinder, when the piston rod is fixed, the movement of the space occupied by the movement of the cylinder cylinder effective stroke is () A, 1 times B, 2 times C, 2 times D, 3 times 14.
(A) A, overflow regulator B, back pressure C, safety protection D, decompression 15. Throttle valve is to control the fluid (A) A, Flow B, Direction C, Pressure D, Pressure and Direction 16.
Hydraulic pump output fluid how much, mainly depends on (C) A, rated pressure B, load C, seal the size of the working chamber volume change D, the motor power 17.
(B) A, hydraulic pump B, hydraulic motor C, hydraulic cylinder D, the control valve 18 has two adjustment pressure of 5MPa and 10MPa relief valve in parallel At the outlet of the hydraulic pump, the outlet pressure of the pump is (A) A, 5 MPa B, 10 Mpa C, 15 MPa D, 20 MPa19.
Internal control, internal drain B, internal control, external drain C, external control, external drain D, external control, internal drain 20.
In the heavy load, and fast and slow movement requirements of mechanical equipment hydraulic system, you can use the following hydraulic pump is (C) A, gear pump B, screw pump C, variable pressure variable displacement vane pump D, shaft To the plunger pump 21.
Single-acting vane pump rotor per revolution, oil absorption, pressure of the oil (C) times.
A, 1 B, 2 C, 3 D, 4 22.
In liquid flow, the phenomenon that a large amount of bubbles are generated due to the pressure at a point lower than the air separation pressure is called (C) A, laminar flow B, hydraulic impact C, hole phenomenon D, turbulent flow 23.
For the decompression circuit to work reliably, the maximum adjustment pressure should be (B) system pressure.
A, greater than B, less than C, equal to D, not equal to 24.
(A) 3 A, hydraulic pump B, hydraulic motor C, hydraulic cylinder D, control valve 25. The magnitude of the hydraulic cylinder movement speed depends on (A) A, Flow B, Pressure C, Flow and Pressure D, Pressure or Flow 26.
The median function is (A) type of directional control valve can be achieved in the unloading system.
A, MB, PC, OD, Y 27.
Double-acting multi-stage telescopic cylinder, the thrust and velocity of the gradual changes in extension, the result is (D) A, thrust and velocity are increased B, thrust and velocity are reduced C, thrust increases, the speed decreases D, reduced thrust, increased speed 28.
There are two pressure regulating valves, 5MPa and 10MPa respectively, connected in parallel with the outlet of the hydraulic pump. The outlet pressure of the pump is (A) A, 5 MPa B, 10 Mpa C, 15 MPa D, 20 MPa 29.
The main ways to improve the working pressure of the gear oil pump are to reduce the axial leakage of the gear oil pump and cause the axial leakage of the gear oil pump mainly because (D) A, the gap B at the gear meshing line, the inner wall of the pump body (hole) The gap between the circle C, the gap between the drive shaft and the bearing D, the gap between both sides of the gear and the end cover 30.
The main reasons that affect the volumetric efficiency of the hydraulic pump (D) A, working pressure B, the internal friction C, the volume change of the working chamber D, the internal leakage 31.
Pressure valve to maintain work (B) A, the same inlet pressure B, the same outlet pressure C, import and export pressure will not change D, import and export pressure has changed 32.
The hydraulic cylinders that can form the differential connection are (C) A, single rod hydraulic cylinder B, double rod hydraulic cylinder C, and piston hydraulic cylinder D,
Internal control, internal drain B, internal control, external drain C, external control, external drain D, external control, internal drain 34.
The role of the relief valve in the metering pump throttling system is (A) A, overflow regulator B, back pressure C, safety protection D, decompression 35.
To achieve rapid movement can be used loop (A) A, differential connection B, speed control valve speed C, the large flow pump oil D, throttling