Lesson-9-Marine-Boilers

精品文档 1欢迎下载 Lesson 9 Marine Boilers 第 9 课 船用锅炉 1 Boilers are used on board ship for producing steam This steam may be used for driving the main engines when steam turbines are fitted or for driving auxiliary machinery such as the windlass There are two basic types of boiler in use in ships the fire tube boiler the terms smoke tube and donkey boiler are also in use and the water tube boiler Both are illustrated in Fig 9 1 船用锅炉用来产生蒸汽 蒸汽在装有蒸汽轮机的船上可用于驱动主机 也可用于驱动辅助 机械 如锚机 船用锅炉有两种基本类型 火管锅炉 也使用 烟管锅炉 和 辅锅炉 这两个术语 和水管锅炉 分别图示如下 9 1 2 Now if you look at the diagram of the fire tube boiler you will see that it consists of a cylindrical steel shell which contains a furnace at the bottom Two or more furnaces may be fitted depending on the size of the boiler The furnace is connected to a combustion chamber situated in the middle part of the boiler Leading from this combustion chamber to a smoke box are a large number of horizontal tubes Some of these are used for supporting the middle section of the boiler and the combustion chamber Connected to the smoke box are the uptakes for the waste gases The furnace the combustion chamber and the tubes are all surrounded by water 在火管锅炉的图中可以看到 它由一个圆筒形的钢外壳构成 其底部有炉膛 根据锅炉的 大小 可以安装两个或更多的炉膛 炉膛和位于锅炉中间位置的燃烧室相通 燃烧室和烟 箱之间设有许多水平烟管 一部分烟管用来支撑锅炉中部和燃烧室 与烟箱相连的是废气 的上升烟道 炉膛 燃烧室和烟管都被水包围着 3 The fire tube boiler is usually of both riveted and welded construction It is strong and is capable of operating with poor quality feed water But there are more efficient types of boiler which can generate more power therefore fire tube boilers are now mainly chosen for low pressure steam production on vessels requiring steam for auxiliary purposes 火管锅炉一般为铆接和焊接结构 结构坚固 能够使用劣质给水工作 但是 有些类型的 锅炉效率更高 能够产生更大量的蒸汽 因此 苏格兰式锅炉 火管锅炉 现在主要为需要 精品文档 2欢迎下载 蒸汽驱动辅助机械的船舶提供低压蒸汽 4 Water tube boilers have replaced fire tube boilers for generating high pressure high temperature high capacity steam for main engines or cargo pump turbines From the diagram you will see that they have a steam drum at the top which is partly filled with water and water drums at a lower level These drums are connected by banks of tubes which also contain water The furnace is located at the bottom and the whole system is contained in a fireproof casing Downcomer tubes are placed outside the gas system to act as feeders to the water drums 水管锅炉已经取代了火管锅炉 产生高压高温大流量的蒸汽 以驱动主机或货油泵透平 从图上可以看到 水管锅炉的顶部有一个汽鼓 部分注水 下部有多个水鼓 汽鼓和水鼓 由管束连接 管内有水 炉膛位于底部 整个系统由耐火外壳包围 下降管安装在燃气系 统之外 用作水鼓的给水管 5 Gases are heated in the furnace and pass upwards through the banks of tubes transferring their heat to the water in the tubes Because the steam drum provides a reservoir of relatively cool water convection currents are set up causing the water to circulate round the system The banks of tubes generating tubes offer a large surface area to the radiant heat of the furnace gases This makes them very efficient Superheaters are added to the system to increase its efficiency These are located between the rows of tubes 在炉膛内加热的燃气向上通过管束 将热量传递给管内的水 因为汽鼓里存储的水温度相 对较低 系统内就形成对流 使水得以循环 管束 蒸发管 提供了一个较大的炉膛燃气 辐射受热面 使蒸发效率很高 过热器加装到系统中 进一步提高了效率 它们一般设置 在管排间 6 Various valves and gauges are fitted to the boilers Those attached directly to the pressure parts of the boiler are known as boiler mountings The mountings usually found on a boiler are safety valves which are needed to protect the boiler against overpressure a main s top valve in order to control the passage of steam to the engines feed check valves to control the final entry of water into the boiler water level indicators to show the level of water in the boiler a blow down valve enables water to be blown down or emptied from the boiler a scum valve enables the blowing down or removal of scum and impurities from the water surface and thermometers for showing the temperature inside the boiler In order to be able t o blow away soot and the products of combustion from the tube surfaces soot blowers are fitted which are operated by steam or compressed air Salinometer valves are also fitted to allow samples of water to be drawn off for testing Chemical dosing valves are also necessary so that chemicals can be added directly into the boiler 锅炉上装有各种阀和测量仪表 直接与锅炉压力部件相连的称为锅炉附件 通常的锅炉附 件有 防止锅炉超压的安全阀 控制通向发动机的蒸汽的主停汽阀 控制锅炉进水量的给 精品文档 3欢迎下载 水止回阀 显示锅炉水位的水位指示器 排出或放空锅炉水的下排污阀 排出或除去水面 浮渣和杂质的上排污阀 以及显示锅炉内部温度的温度计 为了吹除管壁上的烟灰和燃烧 产物 安装了用蒸汽或压缩空气工作的吹灰器 盐度计阀 取样阀 也安装在锅炉上 以 便可以提取样水进行检测 还需要安装投药阀 这样化学制剂就能直接加入锅炉中 B Multiple Choice B 选择题 Questions 1 3 are based on paragraphs 1 3 根据课文第 1 3 段回答问题 1 3 1 Marine boilers are used for producing steam which may be used for 船用锅炉产生的蒸汽是用来 答案 D A driving auxiliary machinery驱动辅机 B driving the main engines驱动主机 C heating heavy oil加热重油 D all of the above上述任何一种 2 A fire tube boiler comprises the following components except 火管锅炉包括以下部件 除了 答案 B A uptakes上升烟道 B downcomers下降管 C a smoke box烟箱 D furnaces炉膛 3 Which of the following statements is not true concerning a fire tube boiler 关于火管锅炉以下哪种说法是不正确的 答案 C 精品文档 4欢迎下载 A The fire tube boiler is usually of both riveted and welded construction 火管锅炉通常兼有铆合和焊接两种结构 B It can operate with poor quality feed water 火管锅炉能够使用劣质给水运行 C It is the most efficient type of boilers 火管锅炉是最有效率的一种锅炉 D It is now mainly chosen for low pressure steam production 火管锅炉现在主要用来产生低压蒸汽 Questions 4 7 are based on paragraphs 4 5 根据课文第 4 5 段回答问题 4 7 4 In a boiler the water flows through the inside of the tubes while the hot gases pass around the outside4 在 锅炉中 水流经管内而炽热烟气从管外通过 答案 A A water tub烟管 B fire tubee水管 C exhaust gas废气 D none of the above以上都不是 5 Gases are heated in the furnace and pass upwards through which offer a large surface area to the radiant heat of the furnace gases 燃气在炉膛内被加热上行经过 它给炉膛燃气提供了很大的辐射受热面积 答案 C A the uptakes上升烟道 B the downcomers下降管 C the banks of tubes管束 蒸发管 D the smoke boxes烟箱 6 A water tube boiler may have the following components except 水管锅炉可能包括以下部件 除了 答案 A A the smoke box烟箱 B the downcomers下降管 C the generating tubes蒸发管 D the water drums and the steam drum水鼓和汽鼓 7 Which of the following components may increase the boiler efficiency 下列哪种部件可能提高锅炉效率答案 A A The superheaters 过热器 B The downcomers 下降管 C The steam drum 汽鼓 D The water drums 水鼓 Questions 8 13 are based on paragraph 6 根据课文第 6 段回答问题 8 13 8 The valve that prevents water from backing out the boiler into the feedline is the 阻止从锅炉返回的水进人给水管路的是 答素 C A bottom blow valve下排污阀 B skin valve皮肤阀 精品文档 5欢迎下载 C feed check valve给水止回阀 D feed stop valve截止阀 9 enables the blowing down or removal of scum and impurities from the water surface 9 可以除掉水面的浮渣和杂质 答素 D A A blow down valve下排污阀 B A soot blower 吹灰器 C A feed check valve给水止回阀 D A scum valve上排污阀 10 The is fitted in the steam supply line and is usually of the non return type 安装在供汽管上并且通常是止回型的 答素 A A main steam stop valve主停汽阀 B auxiliary steam stop valve辅停汽阀 C feed check or control valve给水止回 控制阀 D blow down valve下排污阀 11 are also fitted to allow samples of water to be drawn off for testing the chlorides 也被安装 使得水样得以提取来检测氯化物 答素 A A Salinometer valves盐度计阀 B Water level gauges水位计 C Viscometers 黏度计 D Tachometers转速表 12 are mounted in pairs to protect the boiler against overpressure 成对安装以保护锅炉免于超压 答素 A A Safety valves安全阀 B Water tubes水管 C Steam stop valves 停汽阀 D Blow down valves下排污阀 13 enables water to be blown down or emptied from the boiler 使水从锅炉中放出或者排空 答案 C A A scum valve上排污阀 B A soot blower吹灰器 C A blow down valve 下排污阀 D A vent cock放气阀 Task 2 Vocabulary and Structure 任务 2 词汇与结构 A Technical Terms 专业术语 Translate the following into Chinese 1 烟箱 2 燃烧室 3 汽鼓 4 水鼓 5 下降管 6 蒸发管 7 过热器 8 安全阀 9 主停汽阀 10 给水阀 11 水位计 12 上排污阀 13 吹灰器 14 盐度计阀 15 投药阀 1 smoke box 2 combustion chamber 3 steam drum 精品文档 6欢迎下载 4 water drum 5 downcomer 6 generating tube 7 superheater 8 safety valve 9 main sto