【正文】 external surface of the housing. 對于液壓葉片泵，工作時，轉(zhuǎn)子與葉片接觸。 A. draw the liquid in/force the liquid out B. force the liquid out / draw the liquid in C. suction/draw D. deliver/outlet 1109 Throttling in the ______ line of a centrifugal pump involves the risk of the pump ，節(jié)流吸人管路，會產(chǎn)生氣蝕危險。 ② rotary。 A. kiic/pressure B. kiic/essential C. pressure/kiic D. pressure/height 1103 The amount of fluid delivered by a centrifugal pump can be regulated by _______ 離心泵的排隊(duì)量可通過改變壓力來調(diào)節(jié)，出可通過改變轉(zhuǎn)子的速度調(diào)節(jié)。 A. steady B. in pulsation C. continuous D. large 1099 In a _______ the center screw is driven and the outer screws idle. A. single screw pump B. doublescrew pump在三螺桿泵中，只有中間螺桿被驅(qū)動。 A. depending on B. in relative to C. regardless of D. because of 1090 B 1091 A 1092 A 1093 C 1094 C 1095 A gear pump belongs to _______ according to its working principle. 根據(jù)工作原理，齒輪泵屬于容積式泵。 A. reciprocating pump B. positive displacement pump C. centrifugal pump D. centripetal pump 1091 Through a _______ pump, the liquid is transferred from the suction to the discharge by the mechanical variation of the volume of a chamber or chambers. 對于容積式泵，液體通過泵腔室體積的改變從吸入口排至排出口。 A. positive displacement B. ejector C. centrifugal D. air pressor 1092 A monopump is a singlescrew pump. That means it consists of _______ rotor(s). 單螺桿泵只有一個轉(zhuǎn)子。 A. reciprocating pumps B. positive displacement pumps C. centrifugal pumps D. centripetal pumps 1096 The pressure head of a pump is given in the unit of _______ 泵的壓頭常用“米液柱”高度表示。 C. triple screw pump D. centripetal pump 1100 A Screw pump belongs to _______ according to its working principle. 根據(jù)工作原理，螺桿泵屬于容積式泵。 A. throttling the pressure line B. changing the speed of the rotor C. either A or B D. None of the above is true. 1104 The amount of fluid delivered by a reciprocating pump can be regulated by ______ 往復(fù)泵屬于容積式泵，排量通過改變柱塞的速度來調(diào)節(jié)。 ③ centrifugal. 往復(fù)泵和旋渦泵都具有干吸能力，而離心泵沒有。 A. suction B. exhaust C. pressure D. discharge 1110 As for a hydraulic single action vane pump, the inner wall of the stator is usually of ______ ，靜子的內(nèi)壁通常是圓形。 A. ① only B. ② only C. ① and ② D. ① ② and ③ l l 12 Shaft sealing in a centrifugal pump can be effected by _______ 離心泵的軸封可用機(jī)械密封，也可用填料箱。 A. to fill 2 tanks at the same time B. to use pump at a higher pressure C. to return liquid to suction side if discharge valve is closed D. All of the above are true. 1111 A 1112 C 1113 B 1114 B 1115 C 1116 The pump discharge pressure will be considerably higher than the pressure at the _______泵的排出壓力比泵進(jìn)口支管的壓力要高得多。 A. centrifugal B. plunger C. injector D. water 1120 Which of the following pumps are selfpriming, and can deal with liquid from a level below the pump。 A. ① only B. ① ② and ③ C. ① and ③ D. ① ② and ③ 1116 A 1117 C 1118 A 1119 B. 1120 B 1121 The amount of fluid delivered by a gear pump can be regulated by _______ 齒輪泵屬于容積式泵，排量只能通過改變轉(zhuǎn)子的速度來調(diào)節(jié)。 ③ . screw. 齒輪泵和螺桿泵都是容積式泵，排出閥關(guān)閉’將會產(chǎn)生具有破壞性的壓力，而離心泵不會。 A. ① and ② B. ② and ③ C. ① and ③ D. ① ② and ③ 1125 The _______ pump discharges a nearly constant amount of liquid regardless of pressure. 不管壓力如何，容積式泵的排量幾乎恒定。 A. slack enough to allow slight leakage of fluid B. slightly clocked C. brought up tight so as not to allow any leakage D. fitted with a relief valve 1128 Air chambers are usually fitted to reciprocating pumps in order to ______ 往復(fù)泵中的空氣室用來保持流量穩(wěn)定。 ② It has no internal valves。 ③ gear. ① ② ③ A. ① only B. ① and ② C. ② ③ and ③ D. ① ② and ③ 往復(fù)泵、齒輪泵和葉片泵都具有干吸能力。 A. scaled B. cracked C. shape changed D. deformed 1136 The tube in a boiler should be blinded if found ____鍋爐管子發(fā)現(xiàn)泄露，應(yīng)封死。 A. Safety valves B. Water tube C. Steam stop valves D. Blow down valves 1140 The furnace of a oil fired boiler should be _____ before the operating burner is lit. 鍋爐點(diǎn)火前，應(yīng)進(jìn)行掃氣。 A. to raise water level B. only while making steam C. to remove scum D. when fire are secured 1143 The water level in a steaming auxiliary boiler will always _____ 輔助鍋爐的水位：降隨蒸汽需求量的變化而變化。 1147 Safety valves on a boiler vent to the _____鍋爐安全閥通大氣。 A. Descriptions B. Discrepancies C. Different D. Deflections 1146 A 1147 C 1148 B 1149 B 1150 B 1151 Impurities from the boiler water surface can be removed through the _____ 鍋爐水面的雜質(zhì)可通過上排污閥清除。 A. latent heat of condensation B. latent heat of vaporization C. latent heat of saturation D. sensible heat of condensation 1151 C 1152 B 1153 D 1154 A 1155 A 1156As for an oilfired boiler if at a normal steaming condition and water goes out of sight in gauge glasses the action you should take is: ① secure oil to fires。 A. Water Head Register B. Water Heater Recirculating C. Waste Heat Recov