【正文】 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。 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. 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。 ② rotary。 ③ the external surface of the housing. 對于液壓葉片泵，工作時，轉(zhuǎn)子與葉片接觸。 A. discharges into a gradually widening channel B. has stationary diffuser vanes C. produces no kiic energy D. All of the above are true. 1119 In _______ pumps a closed discharge valve will cause bursting discharge pressure. 柱塞泵是容積式泵，排出閥關(guān)閉將會產(chǎn)生具有破壞性的壓力。 ② . centrifugal。 A. Volute pump B. Diffuser pump C. Regenerative pump D. All of the above 1127 Some pumps use packing as sealing gland. The gland should be ______ 一些泵使用填料作為密封格蘭，注意要少許松一點(diǎn)，讓液體稍微泄漏。 ② vane。 A. watertube B. firetube C. exhaust gas D. None of the above is tree. 1139 _____ are mounted in pairs to protect the boiler against overpressure. 鍋爐安裝安全閥以防鍋爐超壓。 A. take no measures B. extinguish the fire as soon as possible C. feed water to the boiler D. open the blow down valve 1141 B 1142 D 1143 D 1144 D 1145 B 1146 The boiler feed pump discharge pressure is higher than the steam dnnn pressure to _____ A. ensure feed water flow into the boiler B. keep the steam drum pressure high C. prevent water hammer in the feed line D. help the feed water flash to steam 鍋爐給水泵排出壓力比蒸汽筒壓力要高，才能確保給水進(jìn)人到鍋爐。 A. physical state B. temperature C. atmospheric pressure D. sensible pressure 1155 The amount of heat released by steam when it changes to water at the same temperature is called ___在同樣的溫度下，蒸汽變成水時所釋放的熱量，稱為冷凝潛熱。 C. excessive air in the fuel D. cold fuel oil 1156 A 1157 D 1158 C 1159 B 1160 C 1161 The water level showing in a boiler water gauge glass is usually ____ during working. A. higher than the actual drum water level B. equal to the actual drum water level C. increasing due to steam condensation in the glass D. lower than actual drum water level 鍋爐運(yùn)行期間，水位表顯示的水位比鍋筒實(shí)際水位要低。t discharge oil when pumping out oily water from any oil contaminated space. 船舶上的油水分離器能保證船舶排放艙底水等污水時不排油。 A. an oily water separator B. a purifier C. a centrifugal pressor D. a clarifier 1166 C 1167 B 1168 C 1169 B 1170 D 1171 When a clarifier is running the impurities and water collect at the bowl _____ 分雜機(jī)運(yùn)行時，由于雜質(zhì)比重較大，積聚在分離筒的四周。 A. large size of oil globule B. low temperature C. high viscosity D. high flow rate 1178 A hydraulic motor may be driven by _____液壓馬達(dá)是由油來驅(qū)動的。 A. cast B. put C. hold D. let out 1181 B 1182 C 1183 D 1184 B 1185 C 1186 Among the basic categories of equipment, which of the following are used to convert mechanical into hydraulic energy7 在液壓系統(tǒng)中，液壓油泵將機(jī)械能轉(zhuǎn)變?yōu)橐簤耗堋? A. Hydraulic pumps B. Valves C. Hydraulic cylinders D. Hydraulic motors 1194 The single acting cylinder is the simplest form where pressure is applied to the full area of the piston head to move the load through piston rod extension. The load causes rod _____ when the drive pressure is ，壓力作用于整個柱塞頭部，通過柱塞桿的伸展傳遞負(fù)荷。 A. Motors B. Check valves C. Safety valves D. Reducing valve 1201 Which of the following can be used in hydraulic transmission system? 液壓系統(tǒng)中采用液壓油。 A. time B. space C. length D. visibility 1197 In a general cargo crane, _____ is fitted to lift the cargo load. 在回轉(zhuǎn)式起貨機(jī) (克令吊 )中，提升裝置用于裝卸貨物。 A. flow of oil B. pressure of oil C. A and B D. temperature of oil 1190 What type of valve is used to direct the flow of hydraulic fluid? 方向控制閥用來引導(dǎo)液壓流體的方向。 A. hydraulic pumps B. valves C. hydraulic cylinders D. hydraulic motors 1182 _____ are used to handle anchors and 。 A. bowl periphery B. bowl center C. upper surface D. lower surface 1174 For a purifier changing to a gravity disc with smaller hole diameter will move the interface towards the ____對于分水機(jī)，使用較小直徑的比重環(huán)，油水界面會向分離筒中心移動。 otherthan=except。 ③ ，管子損壞以及腐蝕等問題。 A. yellowish flame B. golden yellow flame C. milky flame D. brilliant white flame 1158 . R stands for _____ WHR代表廢熱回收裝置。 A. pleted B. carried out C. cleaned D. steamed 1150 You should frequently pare drammounted and remotereading water level indicators. _____ between these have contributed to failures because of overheating through shortage of water, when a boiler was being oilfired. 鍋筒旁的水位指示器與遙控水位指示器的讀數(shù)要經(jīng)常進(jìn)行比較，兩者的偏差會成為鍋爐運(yùn)行故障 (因缺水而過熱 )的原因。 A. drop as the boiler warms up B. rise as the boiler warms up C. remain unchanged until the boiler is hot enough D. rise and fall with the steam demand 1142 The donkey boiler may be given a bottom blow _____鍋爐熄火后，可進(jìn)行下排污。 A. deformed B. rusted C. crac