轮机英语试题 液压系统和设备.doc

轮机英语Lesson 201817. A hydraulic motor may be driven by_.A. an electric motor B. a diesel engine C. a compressor D. oil1818. In a hydraulic system, _ are used to protect the system from over pressure.A. stop valves B. check valves C. safety valves D. reducing valves1819. Among the basic categories of equipment, which of the following are used toallow the hydraulic energy to be controlled?A. hydraulic pumps B. valves C. hydraulic cylinders D. hydraulic motors1820. Among the basic categories of equipment, which of the following are used toConvert mechanical into hydraulic energy?A. The hydraulic pumps B. Valves C. Hydraulic cylinders D. Hydraulic motors1821. Among the basic categories of equipment, which of the following is used toConvert hydraulic energy into continuous rotary motion?A. Hydraulic pumps B. Valves C. Hydraulic cylinders D. Hydraulic motors1822. The rotor of the hydraulic motor rotates at a speed proportional to the_.A. flow of oil B. pressure of oil C. A and B D. temperature of oil1823. What type of valve is used to direct the flow of hydraulic fluid?A. Relief valve B. Direction control valve C. Stop valve D. Pressure control valve1824. External and internal leakage in hydraulic systems may be caused by_.A. unusual vibration B. excessive worn parts C. abnormal pressure D. any of the above1825. Among the basic categories of equipment, which of the following are used to convert the hydraulic energy into linear motion?A. Hydraulic pumps B. Valves C. Hydraulic cylinders D. Hydraulic motors1826. _ play a very important part in hydraulic systems by preventing interaction between different parts of the hydraulic circuit.A. Motors B. Check valves C. Safety valves D. Reducing valve1827. Which of the following can be used in hydraulic transmission system?A. Hydraulic oil B. Animal oil C. Light oil D. Fuel oil1828. A hydraulic machine is one that uses _ to do work.A. liquid B. steam C. gas D. electricity1829. Hydraulic machinery failures are commonly caused by misalignment of the system components and by_.A. hydraulic fluid contamination B. excessive fluid frictionC. turbulent fluid flow D. fluid pressure surges1830. Hydraulic machinery failures are commonly caused by contamination of the hydraulic fluid and_.A. fluid friction B. fluid turbulence C. component misalignment D. pressure surges1831. Overheating of a hydraulic system may be a result of_.A. changing pump discharge pressure in response to normal load variations B. a high oil levelC. incorrect fluid viscosity D. continued slow re-circulation of the oil1832. Which of the following statements describes the functions of a reservoir used in a hydraulic system?A. Dissipate heat. B. Trap foreign matter. C. Separate air from the oil. D. All of the above.1833. When normal operating pressure is applied to the hydraulic oil used in a high-pressure system, the oil_.A. viscosity will decrease B. volume will increaseC. volume will decrease D. pour point will be reduced1834. Which characteristic or condition will have the greatest effect on increasing a hydraulic oils viscosity?A. Pour point B. Cloud point C. Vacuum D. Pressure1835. Sluggish response or action of the hydraulic actuators may be a result of_.A. insufficient load B. excessively high oil viscosityC. relief-valve pressure setting too high D. reservoir level being maintained two inches above normal1836. Flexible hose under pressure in a hydraulic system will_.A. tend to twist about its long axis B. expand in length and in diameterC. contract in length and expand in diameter D. flex at right angles to the applied pressure1837. Pressure in an operating hydraulic system is developed_.A. only by the pump as its primary function B. by resistance to the fluid flow through the systemC. by the thermal input to the systems fluid D. solely by the charge applied by the accumulators1838. When installing a hydraulic hose, which of the following precautions should be taken?A. The hose should not be twisted.B. The hose should be protected with a sleeve if it is subjected to rubbing.C. There should be some slack in the hose. D. All of the above.1839. Which of the listed pressure control valves would be used to establish the maximum operating pressure of a hydraulic system?A. Pressure-reducing valve. B. Unloading valve. C. Counterbalance valve. D. Pressure-relief valve.1840. In the design of hydraulic piping and equipment consideration is given to minimize turbulence in the hydraulic fluid, as this will cause_.A. molecular fluid vibrationB. energy lossesC. wide pressure variationsD. mechanical damage to control valves1841. If you are given the job of adding hydraulic fluid to a mooring winch, and are not certain as to the type of fluid to use, you should_.A. add fluid that is the same color as the fluid in the reservoirB. add turbine oil because it is always a good substituteC. add any oil that has the same viscosity as the hydraulic fluidD. check the winch manufacturers instruction book1842. A gradual decrease in the discharge pressure of an operating hydraulic pump can be caused by_.A. the four-way control valve failing to shift B. the bleeder valve sticking in the open positionC. cold hydraulic fluid D. a clogged air vent falter on the oil reservoir1843. If the relief valve on the discharge side of a hydraulic pump lifts, the cause could be_.A. a low load on the unit B. a clogged pump suction strainerC. a blockage in the line between the pump and hydraulic motorD. the hydraulic motor turning too fast1844. The major source of chemical contaminants in hydraulic fluid is_.A. microscopic steel shavings B. abrasive waste C. anti-oxidant compounds D. oxidation by-products1845. An internal bypass is provided on some hydraulic system suction strainers to help reduce the possibility of_.A. aeration of the oil B. contamination of the oil C. pump cavitation D. spongy actuator movements1846. Overload protection on hydraulic system is provided by the use of_.A. stop valves B. pressure relief valves C. balance valves D. regulating speed valves1847. It is important with all hydraulic systems to ensure that interlocking arrangements provided for pump or motor control levers are_ before the pump driving motor can be started.A. in the pert position B. in the starboard position C. in the neutral position D. to be dismantled1848. Which of the following hydraulic systems is not one of the three sub-division of the Hydraulic drive system?A. Constant pressure system B. Variable pressure systemC. Variable displacement system D. Constant volume system1849. A variable displacement system of hydraulic drives consists of_.A. a variable displacement axial piston pump B. a constant displacement axial piston pumpC. a reciprocating piston pump D. a centrifugal pump 1850. Among the basic categories of equipment, which of the following is used to convert hydraulic energy into continuous rotary motion.A. hydraulic pumps B. Valves C. hydraulic cylinders D. hydraulic motor1851. _are used to limit the pressure in any particular portion and mainly control the pressure after the valve.A. Relief valve B. Check valve C. Safety valves D. Reduces valve 1852. The rotor of the hydraulic motor rotates at a speed proportional to the _.A .flow of oil B. pressure of oil C.A and B D temperature of oil 1853. What type of valve is used to direct the flow of hydraulic fluid?A. Relief valve B. Check valve C. Stop valve D. Pressure control valve1854. _play a very important part in hydraulic systems by preventing interaction between different parts of the hydraulic circuit.A. Motors B. Check valves C. Safety valves D. Reducing valve1855. Which of the following can be used in hydraulic transmission system?A. hydraulic valves B. animal oil C. light oil D. fuel oil 1856. Among the basic categories of equipment, which of the following are used to convert are hydraulic energy into linear motion? A. hydraulic pumps B. Valves C. hydraulic cylinders D. hydraulic motor1857. Which one of following statements is not true concerning the suitable sites ofthe direct acting relief valve and the pilot operated relieve valve?A. the direct acting relief valve is used for controlling lower flows and pressuresB. the pilot operated relief valve is used for controlling higher flows and pressureC. the pilot operated relief valve is used for controlling lower flows and pressureD. the controlling accuracy of direct acting relief valve is worse than that of the pilot operated relief valve 1858. Compensated flow control, or constant flow valves are used in hydraulic systems to _.A. compensate for major leaks in the system B. maintain the original fluid viscosityC. allow for changes in pressure and temperature within the system D. assure constant fluid temperature1859. If a hydraulic pump is overheating, the cause may be _.A. excessive internal leakage in the pump B. low discharge pressure and fluid flowC. excessive fluid level in the hydraulic reservoir D. operation of the pump at 100% efficiency 1860. Check valve is used to control_A. direction of oil flow B. pressure of return oil C. byass of filter D. high pressure overflow1861. Hydraulic control check valve is generally used to _ in the marine hydraulic mechanism.A control the back pressure of return oil B lock the oil lines under some conditionsC change the direction of oil flow D act as relief valve1862. Overflow valve is used to_A control the fluid flow through it B prevent the pressure before it over the specified valueC make the pressure after it steady D control the direction of oil flow1863. Generally the symbol (GB786.1-93) of overflow valve is _ A B C D1864.The symbol (GB786.1-93) at right side represents _ A. overflow valve B reducing valve C relief valve D sequence valve1865. The symbol (GB786.1-93) at right side represents _ A. overflow valve B reducing valve C relief valve D sequence valve1866. _ can be used to prevent hydraulic system overloaded or keep the pressure of oiloutlet from pump constant.A Overflow valve B Reducing valve C Balancing valve D Reducing valve or balancing valve1867. Which of the following problems will occur if the internal drain at either end of a hydraulic , two-way, spool-type directional control valve cylinder were to become plugged ?A. The reservoir would become vapor bound (范围) B. The valve would be placed in hydraulic lockC. The spring loaded relief ports would openD. The buffering chambers (缓冲室) would be unable to function1868. in the variable delivery pump, moving the spindle more from the central point will cause _ fluid to be pumped and consequently _ pressure is generated to drive the rams.A more; more B more; less C less; more D less; less1869. When the tilting box of a variable stroke axial-piston pump is perpendicular to the pump shaft, which of the following conditions will exist?A the pistons reciprocate B the “B” end cylinder barrel rotates C there is no fluid flow D power is transmitted hydraulically1870. Auxiliary components for hydraulic systems include accumulators, _, reservoirs, heat exchangers, seals, pressure gauges and so on.A hydraulic pumps B filters C reservoirs D hydraulic control valves1871. Auxiliary components for hydraulic systems include accumulators, filters, reservoirs, _, seals, pressure gauges and so on.A hydraulic control valv