过程装备与控制工程专业英语翻译

过程装备与控制工程专业英语翻译

第一篇：过程装备与控制工程专业英语翻译

1、In our comparison of the net electrical power output of

both combined heat and power(CHP)and power-only plants, the

electrical output of the CHP plants is assumed to be the output

that could the oretically be produced if there were no heat

electrical power净电力

combined heat and power热电联供

Plant设备

be assumed to be假设为

Theoretically理论地；理论上

在我们的热电联供和只供电的设备的净电力输出比较中，热电联供设备的电力输出是看做理论上如果没有热输出时产生的输出量。

2、The lower heating value is defined here as the higher

heating value(HHV)minus the energy necessary to evaporate the

water that is created by the combustion of the hydrogen in the

fuel and minus the energy needed to evaporate the moisture that

was already part of the fuel before g value热值

Evaporate [ɪ'væpəret]

vt.使……蒸发；使……脱水；使……消失

vi.蒸发，挥发；消失，失踪

Combustion [kəm'bʌstʃən] n.燃烧，氧化；骚动

moisture ['mɒɪstʃə] n.水分；湿度；潮湿；降雨量

低热值在这里定义为高热值减去使水分蒸发所需要的能量，这些能量包括使燃料中的氢燃烧产生的水分蒸发所必需的能量和使燃料燃烧前所含有的水分蒸发所需要的能量。

3、In the case of biomass combustion , however, this will be

possible on only very large scales, whereas atmospheric biomass

gasification is projected to attain these efficiencies on

considerably smaller scales。

biomass [‘baɪə(ʊ)mæs] n.生物质

biomass combustion 生物质能

large scales 大规模

gasification [,ɡæsifi'keiʃən] n.气化

可是对于生物质能，它将可能仅在非常大的范围内获得，然而在大气中的生物质气化将在相当小的范围内获得这些效能。

1、In developing countries like Ghana where solid waste

disposal is increasingly an environmental burden with its

attendant health hazards, the idea of converting the organic

fraction of municipal solid waste into energy for the national grid

is a welcome proposition towards reducing volumes of domestic

waste to be disposed of or al—n.处理；

burden—n.负担；

attendant—随员、伴随的；

hazard—n.危害；

convert—v.转化；

organic fraction—有机部分；

municipal—市政的；

the national grid—国家电网；

proposition—提议

volumes of—大量的；

在像加纳这样的发展中国家中，因为伴随着健康危害，固体垃圾处理正日益成为环境负担，而把城市生活垃圾转换成电能并输送到国家电网中的想法，对于减少将被处理或填埋的大量的生活垃圾来说，是一个不错的提议。

2、In spite of the perceived low heating values of

biodegradable waste, the increasing volumes of MSW as well as

the generally high percentage of the organic component

observed in Ghana’s MSW means that the amount of energy

that can be obtained from the waste is not

ve—v.感觉、认知；

biodegradable—可生物降解的；

insignificant—微不足道的；

尽管我们所感知的可生物质降解的垃圾热值低，但加纳持续增长的大量的城市生活垃圾和其被观察到的普遍高含量的有机成分意味着蕴藏其中的可被利用的能量值是不容小觑的。

3、Thus, a combined cycle plant can be designed that uses

the hot flue gases produced from organic waste combustion to

generate steam and gasify liquid methane in stages to turn a

steam turbine and a gas turbine respectively , and the flue gases,

cooled down, can be used to pre-dry the organic waste in a cycle

for use as fuel to increase the efficiency of the —v.气化；

turbine—涡轮机；

因此，一个联合循环电厂可以被设计成这样：使用有机垃圾燃烧产生的热烟气分步地去生产蒸汽去转动蒸汽轮机和气化液态甲烷去转动燃气轮机，然后被冷却下来的烟气可作为燃料循环地用于预热有机垃圾以提高电厂的效率。

4、It is further comparable to a coal-fueled power plant with

respect to flue gas emissions and solid residues from the

combustion process and flue gas on—n.排放；

combustion—n.燃烧；

flue—烟道；

这是进一步就烟气排放和在燃烧过程、烟气清理中的固体残留与燃煤发电厂的比较。

王局长：

Hydrogen production from biomass can contribute not only

to large-scale development and utilization of renewable energy,

improve energy structure and reduce pollution as well as to meet

people's demand for clean energy, but also is the most viable

hydrogen production methods from renewable energy near the

s: n.生物质

large-scale:adj.大规模的，大量的utilization:n.使用，利用

renewable:adj.可持续的，可再生的viable:adj.切实可行的利用生物质制氢不仅可以促进可再生能源的大规模开发利用，改善能源结构，减少环境污染，满足人们对清洁能源的需求，而且是近中期最为可行的可再生能源制氢方式。

Biomass gasification in supercritical water(SCW超临界水)is a

promising technology for Hydrogen production from biomass,

which is based on the special physical and chemical properties of

water near the critical point.

第二篇：过程装备与控制工程专业英语翻译10

Reading Material 10

Corrosion Control

Corrosion problems can be solved in the following ways:

(1)Select a material that is resistant to be the corrosion

environment.(2)Give metal a protective coating.(3)Change the

service conditions, such as temperature, pressure, or

velocity.(4)Change the environment chemistry such as pH,

concentration, aeration, or impurities.(5)Add a corrosion

inhibitor.(6)Shift the electric potential of the metal by cathodic or

anodic protection

(7)Modify the design of the equipment or system.(8)Let it

corrode and replace it(often a viablealternative!)

Once the engineer has determined that there is no danger of

a catastrophe, deciding which way to combat corrosion usually

comes down to the economics of the al Selection

Stainless steels are usually the first choice for a “probably

corrosive” environment with unknown properties, because

these alloys are resistant to a wide range of oxidizers, but they

cannot withstand strong reducing solutions, such as hydrochloric

ess steels can be corroded, despite their

stainless steels are classified into five general groups(martensitic,

ferritic, austenitic, duplex and precipitation-hardenable strainless

steels)according to their metallurgical structures, with the of

which one to use depending not only on corrosion resistance but

also on required strength and cially pure nickel has

high corrosion resistance, especially to alkalies, combined with

mechanical properties similar to mild steel, and good

and nickel alloys widely used in the food

industry and are frequently selected for service in chlorine,

hydrogen chloride, and chlorinated are very

resistant to high-temperature air and to stress-corrosion

um is a very reactive metal in the standard

electromotive force series;it immediately reacts with air to form a

passive film consisting of two layers: an inner, compact,

amorphous oxide and an outer, thicker, more permeable

hydrated um is naturally compatible with the

atmosphere and withstands many solutions well if the pH lies

between about 4 to acids and moderately strong bases

destroy aluminum’s passive de ions are particularly

damaging because they attack the film only at weak spots and

pit chlorinated organic solvents and alcohols

can attack aluminum alloys disastrously, sometimes

tive Coatings

The major purpose of coating a metal is to protect it from a

corrosive environment when the metal is otherwise suitable for

the service conditions in terms of mechanical and physical

g metal with good mechanical properties

(usually steel)is often more practical in terms of cost and

required life than selecting a more corrosion resistion but

expensive tion can be achieved in four ways, with

many coatings functioning in more than one way:

(1)A barrier coating that prevents the corrosive environment

from contacting the metal.(2)A sacrificial coating that corrodes

while giving cathodic protection to the underlying metal.(3)An

inhibitor coating that slows electrode reactions.(4)An electrically

resistive coating that stifles electrochemical corrosion cells,

Paints fall into this last ion Inhibitors

An inhibitor is a chemical added to the corrosive

environment in small amounts to reduce the corrosion

inhibitors interfere with the anode reaction, some with the

cathode reaction, and some with usually used to

prevent general corrosion but most are not effective in

preventing localized attack, such as crevice corrosion, pitting, or

stress-corrosion tors have a critical concentration

that must be reached or exceeded for them to be effective, and

in some cases to prevent them from making corrosion

ic and Anodic Protection

Cathodic protection converts all anodic on a metal surface to

cathodes so that corrosion protected metal has

positive current flowing onto it from the electrolyte everywhere

on the surface so that no current flows result can be

achieved in two distinictly different ways.(1)By connecting a

sacrificial anode the metal that is be protected.(2)By applying an

electric current from a separate source, a technique called

impressed-current cathodic protection, on the

contray, makes the entire metal surface anodic-so anodic that the

metal completely sly, then, this technique is

limited to metals that can form protective passive

passivated metals still corrode at a low rate, anodic protection

almost, but not completely, stops corrosion

problems originate with either improper design or improper

material r, a good choice of material can

overcome severe environmental conditions and even some

deficiencies in methods listed above are the accepted

ways of dealing with a corrosion problem, but not all of them

apply in a given particular, the corrosion engineer

often cannot change the service conditions or environment

may be as unalterable as the ocean, or nearly as

unalterable: an industrial process that is running fairly smoothly

where any change will be fanatically opposed by the production

people.阅读材料10

腐蚀控制

腐蚀问题的解决方法如下：

（1）选择抗腐蚀环境的材料；

（2）给金属加一个保护层；

（3）改变工作条件，如温度，压力或速度；

（4）改变化学环境，如PH值，浓度，通风，杂质；

（5）添加缓蚀剂；

（6）改变金属阳极或阴极保护的电势；

（7）完善设备或系统的设计；

（8）让其腐蚀后取代它（通常是一个可行的替换物）。

上面所列的方法来处理腐蚀问题是可行的，但是不是所有的都能应用于一个给定的情况。特别是，腐蚀工程师常常不能改变操作条件或者化学环境。这就像在海洋上不能改变一样或者是基本不能改变。一个运行相当平稳的工业过程，其中任何改变都将遭到生产人员的强烈反对。

大多数的腐蚀问题是由不正当的设计或不正当的材料选择引起的。然而，材料的优良选择可以克服一些恶劣的环境条件甚至是一些设计上的缺陷。

工程师一旦确定没有安全隐患，抗腐蚀的方法就转移到经济形势上了。

材料的选择

不锈钢通常作为一个具有未知性质、“可能腐蚀”环境的首选材料，因为这些合金可以抵抗大范围的氧化剂，但它们不能承受强还原性的溶液，例如盐酸溶液。不锈钢可以被腐蚀尽管它们的名字是那样说的。根据合金结构不锈钢被分为五大类（马氏体，铁素体，奥氏体，双链体和析出可硬化不锈钢）。选择哪一种钢不仅要根据它的耐腐蚀性，而且要根据其所需的强度和成本。

商业上的纯镍具有很强的耐腐蚀性，尤其是对碱金属，结合与低碳钢相似的机械性能和良好的焊接性。镍和镍合金广泛运用于食品工业，经常使用于制氯业气，氯化氢，氯化碳氢化合物。它们对高温气体应力腐蚀破裂有很强的抵抗性。

铝在标准的电动压系列下是一种很活泼的金属，它可以立即跟空气反应形成由两层物质组成的钝化膜：里面一层是紧密的非晶氧化薄膜，外面是更厚的可透性氢氧化物。铝可以跟空气兼容，可以防止很多ＰＨ值为４到９的溶液。强酸和适量强碱会破坏铝的钝化膜。尤其是氯离子破坏有微弱和凹坑的铝的氧化膜。很多氯的有机溶剂和醇类严重损害铝合金，有时甚至是爆破性的。

防护涂料

给材料加上涂层的目的是为了保护金属在腐蚀性环境中不被破坏，除非金属的机械性能和物理性能能符合工作条件。给机械性能好的金属（通常是钢）加保护涂层常比选择一种耐腐蚀但昂贵的材料更符合实际和生活要求。

保护可以通过四种方法获得，很多涂层功能不仅仅是一种。

（1）防渗涂层可以防止金属与腐蚀环境接触。

（2）给底层金属作阴极保护的涂层会被腐蚀掉。

（3）使用抑制剂减缓电极反应。

（4）电阻涂层抑制电化学腐蚀单元，涂料落在这最后的范畴。

缓蚀剂

抑制剂是一种添加到腐蚀环境中的少量化学药品，以降低腐蚀速度。有些抑制剂是影响阳极反应，有些是影响阴极反应，有些是两种都影响。他们通常被用于保护大体的腐蚀，但是对于保护局部腐蚀大部分是无效的，比如隙间腐蚀，点状腐蚀，应力腐蚀破裂。抑制剂必须要达到或者超过临界浓度才会有效的，在某些情况下，抑制剂保护金属不更严重腐蚀。阴极和阳极保护

阴极保护是使金属表面所有阳极转变为阴极而使腐蚀停止。有一个从金属表面任何的电解液的正向电流流进被保护金属，以致没有电流流出。有两种明显不同的方法可以得到这样的结果。

（1）接上一个牺牲阳极，金属就得到保护。

（2）通过单独的电源施加电流，这种技术称为外加电流阴极保护法。

相反地，阳极保护是把整个金属表面变成阳极，金属就完全被钝化。显然，这种技术对能形成保护钝化膜的金属具有局限性。因为钝化的金属仍然以很小的速度腐蚀，阳极保护几乎但不是完全能停止腐蚀。

第三篇：过程装备与控制工程专业专业英语翻译9

Reading Material 9

Heat Treatment of Steel

Types of Heat Treating OperationsFive operations are

detailed in this lesson as the basis of heat ations

of these

Operations RelievingWhen a metal Is heated，expansion occurs which is more or less proportional to the

temperature cooling a metal,the reverse reaction takes

is, a contraction is observed．When a steel bar or

plate is heated at one point more than at another，as in welding

or during forging，Internal stresses are set up．During heating,

expansion of the heated area cannot take place unhindered，and

it tends to deform．On cooling，contraction is prevented from

taking place by the unyielding cold metal surrounding the heated

area．The forces attempting to contract the metal are not

relieved，and when the metal is cold again，the forces remain

as internal stresses．stresses also result from volume changes,

which accompany metal transformations and

precipitation．Internal or residual stresses are bad because they

may cause warping of steel parts when they are machined．To

0relieve these stresses，steel is heated to around 595C，assuming that the entire

part is heated uniformly, then cooled slowly back to room

temperature．This procedure is called stress relief annealing, or

merely stress e of characteristics inherent in cast

steel, the normalizing treatment is more frequently applied to

ingots prior to working，and to steel castings and forgings prior

to izingThe process of normalizing consists of

heating to a temperature above the third transformation

temperature and allowing the part to cool in still actual

temperature required for this depends on the composition of the

steel,0but is usually around ly, the term normalize

does not describe the

process might be more accurately described as

a homogenizing or grain-refining any piece of

steel, the composition is usually not uniform is,

one area may have more carbon than the area adjacent to

compositional differences affect the way in which the

steel will respond to heat it is heated to a high

temperature, the carbon can readily diffuse throughout, and the

result is a reasonably uniform composition from one area to the

steel is then more homogeneous and will respond to

the heat treatment in a more uniform cold

deformation, steel has a tendency to harden in deformed areas,

making it more difficult to bend and liable to ate

deforming and annealing operations are performed on most

manufactured steel annealingFull annealing, where

steel is heated 50 to 100C above the third transformation

temperature for hypoeutectoid steels, and above the lowest

transformation temperature for hypereutectoid steels, and slow

cooled, makes the steel much easier to cut, as well as full

annealing, cooling must take place very slowly so that a coarse

pearlite is cooling is not essential for

process annealing, since any cooling rate from temperatures

below the lowest transformation temperature will result in the

same microstructure and s annealingProcess

annealing consists of heating steel to a temperature just below

the lowest transformation temperature for a short

makes the steel easier to heat treatment is commonly

applied in the sheet and wire industries, and the temperatures

generally used are from 550 to ing The two--stage

heat treating process of quenching and tempering is designed to

produce high strength steel capable of resisting shock and

deformation without the other hand, the annealing

process is intended to make steel easier to deform or machine.1n

manufacturing steel products, machining and severe bending

operations are often tempered steel may not cut

or bend very easi1y and annealing is often effect

of tempering may be il1ustrated as the head of a

hammer were quenched to a fully martensitic structure, it

probably would crack after the first few ing during

manufacture of the hammer imparts shock resistance with only a

slight decrease in ing is accomplished by

heating a quenched part to some point below the transformation

temperature, and holding it at this temperature for an hour or

more, depending on its steels are tempered between

205°C and 595° higher temperatures are employed,

toughness or shock resistance of the steel is increased, but the

hardness and strength ingDuctility is the ability

of a metal to change shape before it y quenched

martensite is hard but not ductile;in fact, it is very

ing is needed to impart ductility to the martensite,

usually at a small sacrifice in addition, tempering

greatly increases the resistance of martensite to shock

TreatmentThe hardest condition for any given steel

is obtained by quenching to a fully martensitic

hardness is directly related to strength, a steel composed of 100%

martensite is at its strongest possible r,

strength is not the only property that must be considered in the

application of steel ity may be equally

or modify the magnetic properties of

e the electrical properties;

Improve the machinability;

Increase the toughness;that is, to produce a steel having

both a high tensile strength and good ductility, enabling it to

withstand high impact;

Increase the hardness so as to increase resistance to wear or

to enable the steel to withstand more service conditions;

Decrease the hardness and increase the ductility;

Secure the proper grain structure;

Refine the grain structure of hot worked steels which may

have developed coarse grain size;

Remove stresses induced by cold working or to remove

stresses set up by nonuniform cooling of hot metal objects;

Reasons for Heat TreatingHeat treatment of steel is usually

intended to accomplish any one of the following objectives:

Stress relievingStress relieving is the heating of steel to a

temperature below the transformation temperature, as in

tempering, but is done primarily to relieve internal stress and

thus prevent distortion or cracking during is

sometimes called process ing Tempering

consists of reheating a quenched steel to a suitable temperature

below the transformation temperature for an appropriate time

and cooling back to room this process makes

steel tough will be discussed ing Hardening is carried

out by quenching a steel, that is, cooling it rapidly from a

temperature above the transformation is

quenched in water or brine for the most rapid cooling, in oil for

some alloy steels, and in air for certain higher alloy

steel is quenched, it is usually very hard and brittle;it may even

crack if make the steel more ductile, it must be

izingNormalizing is identical with annealing,

except that the steel is air cooled;this is much faster than cooling

in a is normalized to refine grain size, make its

structure more uniform, or to improve

annealingFull annealing is the process of softening steel by a

heating and cooling cycle, so that it may be bent or cut

annealing, steel is heated above a transformation temperature

and cooled very slowly after it has reached a suitable

distinguishing characteristics of full annealing

are:(a)temperature above the critical temperature and(b)very

slow cooling, usually in the furnace.阅读材料9

钢的热处理

各种不同的热处理操作 本单元介绍了五种热处理的基本方法。这些方法介绍如下。

完全退火完全退火是对钢进行反复的加热和冷却使钢软化的过程，这样就容易弯曲和切割。在退火中，使钢加热到转变温度以上的一个适宜温度后缓慢地冷却。完全退火的突出的特点是：（a）温度高于临界温度（b）缓慢冷却，通常是炉冷。

正火正火和退火相同，除了钢是被空冷的；这比在炉中冷却得更快。钢的正火是为了改善晶粒大小，使它的结构更加均匀，或者是提高机械性能。

淬火淬火就是通过冷浸钢，那就是使钢从转变温度以上的一个温度快速冷却。为了最快的冷却，钢被冷浸在水中或是盐水里，合金钢的是在油里，某些更高合金钢的要在空气中冷却。当钢被淬火之后，它通常是硬和易碎的；甚至落地会破碎，为了使钢更有韧性，它必须被回火。

回火回火是指重新加热已经被淬火的钢到转变温度以下的一个适当温度一段时间后再冷却到室温。至于该过程怎样使钢变得有韧性，我们将在以后讨论。

去应力是指加热钢到转变温度以下的适宜温度，正如回火一样，但这样做是为了减少内应力从而避免在加工过程中的变形和破裂。这有时也被称作退火过程。

热处理的原因钢的热处理通常是为了达到以下的任一目的：

消除冷却过程中产生的内应力和高温金属物体因冷却不均匀而产生的应力。

改善热处理钢可能产生的粗糙晶粒的晶粒结构。

得到适当的晶粒结构

降低硬度，提到塑性。

增加硬度，以提高到钢的抗耐磨性和加强钢使之能承受更多的使

用条件。

增加韧性，这就是使钢同时拥有高的拉伸强度和好的延展性，使它能承受高的撞击。提高切削性能

提高导电性。

改变或修正钢的磁性。

热处理任何一种钢通过淬火而获得完全的马氏体是最难的。由于硬度直接关系到强度，一种钢由100%的马氏体组成是其处于最高强度的可能条件。但是，在钢的应用部分里，强度不是唯一的必需考虑的性能。延展性同样重要。

回火延展性是金属在破裂前改变形状的能力。淬火马氏体很硬但不能延展，事实上它是非常碎的。回火是用来使马氏体获得可延展性，通常强度会降低一些。另外，回火大大增加马氏体抵抗冲击负荷的能力。

回火的影响举例说明如下:如果一个锤头被淬火到完全马氏体结构，它可能在前几次敲击就会破碎。回火在锤头的制造中能增加抗敲击能力，而硬度只有一点点的下降。回火过程是这样达到的：把淬火后的部分加热到转变温度的某点，然后维持这温度一个小时或更多，这要根据部件的大小判断。大多的钢是被加热到205°C到595°C，更高的温度，钢的韧性和抗敲击能力会增加，但硬度和强度会下降。

退火淬火和回火两个热处理过程来生产高强度的钢以便抵抗冲击和变形而不受破坏。另一方面，退火过程的目的是为了使钢更容易变形和机器加工。在钢产品的制造中，机器加工和严格的弯曲操作经常被运用到。即使回火钢也不会被经意的切割和弯曲，退火就常常是不可缺少的。

退火过程退火过程就是加热钢到稍低于最低转变温度的一个温度后保持一会儿。这使钢更容易成形。这种热处理通常应用于薄板和电线工业，它的温度一般在550度到650 度之间。

完全退火完全退火对于亚共析钢要将温度加热到第三转变温度以上50~100℃，对于过共析钢，要加热到最低转变温度以上，然后缓慢冷却，使钢更容易切割和弯曲。在完全退火中，冷却必须要非常缓

慢地进行从而形成粗糙的珠光体。退火过程不必需要缓慢冷却，因为最低转变温度下的任何冷却速度都会得到相同的微观结构和硬度。

在冷变形中，钢有一种在变形中变硬的趋势，使之更难于弯曲和被破坏。大多数的机械加工钢产品都需要交替变形和退火操作。

正火正火过程包括将温度加热到第三转变温度以上，然后让该加热部分在空气中冷却直到与空气温度相同。实际所需的温度要根据钢的组成部分来确定，但通常在870°C左右。其实正火这个术语不是描述目的，该过程被描述成均匀或细化晶粒处理会更准确。任何一块钢，它的组成部分通常是不统一的。那就是说，一块区域可能比周围的含有更多的碳。这种成分的不同会影响热处理的方法。如果加热到一个高的温度，其中的碳能扩散到四周，结果理所当然的刀均匀的成分。这样钢的成分就会更均匀从而使热处理方法更统一。

由于铸铁的固有性质，对工作前的铸铁块，硬化前的钢的铸件和锻件，正火处理会运用得更频繁。

去应力当一块金属被加热时就会发生膨胀，膨胀的多少跟温度的上升成比例。当冷

却一金属，就会发生相反的反应。那就是说，金属的收缩可以被观测到。当一根钢棒或钢板被加热到一个点高于另一个点，就像焊接或锻造一样，内应力就会产生。在加热过程中，被加热部分不能自由膨胀，就会转为变形。在冷却时，热部分周围的冷金属就会阻止收缩。打算使金属收缩的力并没有减少，当金属再次被冷却时，这个力与内应力一样不变。体积的变化同样能产生应力，这个应力随着金属转变和沉淀。内应力和残余应力是不好的因为它使钢的加工部分产生弯曲。为了减少这种应力，钢被加工到约595°C，假设所有的部分被均匀加热，然后缓慢冷却到室温。这步骤就叫做去应力退火，或仅仅叫去应力。

第四篇：过程装备与控制工程专业英语翻译 20

Reading material 20

Basic Stirred Tank Design

The dimensions of the liquid content of a vessel and the

dimensions and arrangement of impellers, baffles and other

internals are factors that influence the amount of the energy

required for achieving a needed amount of agitation or quality

of internal arrangements depend on the objectives of

the operation: whether it is to maintain homogeneity of a

reacting mixture or to keep a solid suspended or a gas dispersed

or to enhance heat or mass transfer.A basic range of design

factors, however, can be defined to cover the majority of the

cases, for example as in Fig.4.4(a).The Vessel A dished bottom

requires less power than a flat a single impeller is to

be used, a liquid level equal to the diameter is optimum, with the

impeller located at the center for an all-liquid ic

and manufacturing considerations, however, often dictate higher

ratios of depth to s Except at very high Reynolds

numbers, baffles are needed to prevent vortexing and rotation of

the liquid mass as a solids are present or when a

heat transfer jacket is used, the baffles are offset from the wall a

distance equal to one-sixth the baffle width which is about one-twelfth the tank radial baffles at equal spacing are

standard;six are only slightly more effective, and three

appreciably less the mixer needed, particularly at low

Tubes A draft tube is a cylindrical housing around

and slightly larger in diameter than the height may

be little more than the diameter of the impeller or it may extend

the full depth of the liquid, depending on the flow pattern that is

y draft tubes are used with axial impellers to direct

suction and discharge impeller-draft tube system

behaves as an axial flow pump of somewhat low top

to bottom circulation behavior is of particular valve in deep tanks

for suspension of solids and for dispersion of er Size

This depends on the kind of impeller and operating conditions

described by the Roynolds, Froude, and Power numbers as well

as individual characteristics whose effects have been

the popular turbine impeller, the ratio of diameters

of impeller and vessel falls in the range, d/Dt0.30.6, the lower

values at high rpm, in gas dispersion, for er Speed

With commercially available motors and speed reducers,

standard speeds are 37, 45, 56, 68, 84, 100, 125, 155, 190, and

320 requirements usually are not great enough to

justify the use of continuously adjustable steam turbine

-speed drives may be required when starting torques

are high, as with a settled er Location As a first

approximation, the impeller can be placed at 1/6 the liquid level

off the some cases there is provision for changing the

position of the impeller on the off-bottom suspension

of solids, an impeller location of 1/3 the impeller diameter off the

bottom may be of Impellers A rotating impeller

in a fluid imparts flow and shear to it, the shear resulting from

the flow of one portion of the fluid past ng cases of

flow are in the axial or radial directions so that impellers are

classified conveniently according to which of these flows is

reason of reflections from vessel surfaces and

obstruction by baffles and other internals, however, flow patterns

in most cases are e the performance of a particular

shape of impeller usually cannot be predicted quantitatively,

impeller design is largely an exercise of judgment so a

considerable variety has been put forth by various

manufacturers.A few common types are illustrated on

Fig.4.4(b)(i)and are described as follows:

three-bladed mixing propeller is modeled on the

marine propeller but has a pitch selected for maximum

are used at relatively high speeds(up to 1800

rpm)with low viscosity fluids, up to about 4000 stabilizing

ring shown in the illustration sometimes is included to minimize

shaft flutter and vibration particularly at low liquid

turbine with flat vertical blades extending to the shaft is suited

to the vast majority of mixing duties up to 100000 cP or so at

high pumping horizontal plate to which the

impeller blades of this turbine are attached has a stabilizing

rd curved blades may be used for the same reason

as for type e with blades are inclined

45(usual,ly).Constructions with two to eight blades arde used,

six being most ed axial and radial flow are

ally effective for heat exchange with vessel walls

or internal blade turbines effectively disperse

fibrous materials without swept back blades have a

lower starting torque than straight ones, which is important

when starting up settled ed turbines consisting

of a rotor and a stator ensure a high degree of radial flow and

shearing action, and are well adapted to emulsification and

paddles fit the contour of the container,

prevent sticking of pasty materials, and promote good heat

transfer with the paddles are used in wide, shallow

tanks and for materials of high viscosity when low shear is

speeds are low.阅读材料20

基本搅拌槽设计

容器的液体容量、叶轮、挡板和其他内部构件的尺寸和安装是影响振动次数和搅拌质量的因素。内部构件的安装取决于操作的目的：是为了保持反应混合物的均匀或是固体悬浮物或是气体的分散或是为了提高传热系数。设计的基本因素，可以包括大多数情况，如图4.4

（a）所示：

容器下凹的底部和平底的比起来需要更少的能量。若仅需一个搅拌器，则对于全液体系统来说，液面高度和直径相等、将搅拌器安装于中心是最好的。若从经济性和制造的角度考虑，则要求更深的深度。

挡板除非雷诺数很高，否则都需要用挡板来防止涡流和液体的整体旋转产生的洞。若出现固体或使用传热套，需在离壁面距离为六分之一叶轮宽度或容器十二分之一直径地方装支管。等距安装四个辐射状的挡板是标准的安装模式。六个只能小幅提高效率，三个就明显不行了。若搅拌器的轴偏离中心，搅拌就不会产生明显的漩涡，挡板也可以不用，尤其是在低黏度情况下。

循环管循环管程圆柱状，直径比叶轮稍大。高度比叶轮直径小些，也可以和液体深度等高，依据流动形式的要求决定。通常循环管用在轴向叶轮处用于引导吸入或排流。叶轮-循环管

系统用作轴向流动泵，只是效率有些低。它从顶部至底部的循环对于深容器的固体悬浮物和气体分散物来说具有特殊的作用。

叶轮的尺寸取决于由雷诺数、佛罗德数和动力数值描述的叶轮的种类及操作条件，这些条件同样和液体性质有关联。对于常用的叶轮机叶轮来说，叶轮直径和压力容器下陷的比率范围在0.3~0.6之间，高转速时比值更低，在气体分离时用到。

叶轮的转速商用电动机和减速器的标准转速是37,45,56,68,84,100,125,155,190和320转/秒。动力要求对于决定是否使用可调蒸气叶轮机来说通常不够。当起始转矩很高时就需要两级速度来固定泥浆。

叶轮的位置首先，叶轮被安装在距离底部约六分之一液体深度的地方。有时也可以将其安装于轴上。为了远离底部的固体悬浮物，叶轮须离底部约叶轮直径三分之一处以保证安全。叶轮的种类旋转的叶轮传动流体并对其产生剪力，剪力从流体的一部分传递到另一部分。流动的极限情况是在垂直或辐射状位置，这使得通过流体流过叶轮方式将叶轮很好的分类。由于容器壁的阻挡、挡板的阻碍以及其他内部构件的原因，常常会并存很多种类的液流。由于叶轮的形状很难精确

的计算出，因此叶轮的设计就成了一项庞杂的工作，也因此推出了很多方案。图4.4（b）~（i）列出了一些常见的方案，描述如下：

B．三叶螺旋桨被安装于水下螺旋桨上，其间距由湍流最大值决定。它们在低粘度(最高4000cp)液体中保持相对较高的转速（可达1800转/分）。图中所示稳定圈用来减少轴的振动和低液面时的特殊振动。

C．在轴上安装直叶轮可适用于粘度高达10000cp的液体，因此其泵的容量很大。

D．在叶轮机上安装水平的浆有保持平衡的作用。如图e中向后弯的浆也有同样的作用。E．叶轮机上的浆倾斜45°。通常会用到2~8个浆，6个是用的最多的。可形成轴向和辐射状的液流。对于容器壁和内部绕流的热交换尤其有效。

F．弯曲状叶片对于搅拌纤维状材料且不产生污浊尤其有效。后弯的浆相较于直浆来说其启动力矩较小，该数值对于有固定泥浆很重要。

G．由定子和转子组成的叶轮机用以保证较高的辐射状液流以及剪切的动作，适用于乳化和分散。

H．锚状浆适合容器的轮廓，防止浆状材料的凝结，提高和容器壁间的转热效率。

I．门状浆适用于低剪力下尺寸宽、深度小的容器，高粘度的液体。叶轮机的转速较低。

第五篇：过程装备与控制工程专业英语翻译 16

Reading Material 16

PressureVesselCodes

History of Pressure Vessel Codes in the United StatesThrough

the late 1800s and early 1900s, explosions in boilers and pressure

vessels were frequent.A firetube boiler explosion on the

Mississippi River steamboat Sultana on April 27, 1865, resulted in

the boat’s sinking within 20 minutes and the death of 1500

soldiers going home after the Civil type of catastrophe

continued unabated into the early 1905, a destructive

explosion of a firetube boiler in a shoe factory in Brockton,

Massachusetts, killed 58 people, injured 117 others, and did

$ 400000 in property 1906, another explosion in a

shoe factory in Lynn, Massachusetts, resulted in death, injury, and

extensive property this accident, the

Massachusetts governor directed the formation of a Board of

Boiler first set of rules for the design and construction

of boilers was approved in Massachusetts on August 30,

code was three pages 1911, Colonel ,

the president of the American Society of Mechanical Engineers,

established a committee to write a set of rules for the design and

construction of boilers and pressure February 13,

1915, the first ASME Boiler Code was was entitled

“Boiler Construction Code, 1914 Edition.” This was the

beginning of the various sections of the ASME Boiler and

Pressure Vessel Code, which ultimately became Section 1, Power

first ASME Code for pressure vessels was issued as

“Rules for the Construction of Unfired Pressure Vessels, ”

Section Ⅷ, 1925 rules applied to vessels over 6

diameter, volume over 1.5 ft3, and pressure over 30

December 1931, a Joint API-ASME Committee was formed to

develop an unfired pressure vessel code for the petroleum

first edition was issued in the next 17 years,

two separated unfired pressure vessel codes 1951, the

last API-ASME Code was issued as a separated 1952,

the two codes were consolidated into one code-the ASME

Unfired Pressure Vessel Code,Section Ⅷ.This continued until the

1968 that time, the original code became Section Ⅷ,

Division 1, Pressure Vessels, and another new part was issued,

which was Section Ⅷ, Division 2, Alternative Rules for Pressure

ANSI/ASME Boiler and Pressure Vessel Code is issued

by the American Society of Mechanical Engineers with approval

by the American National Standards Institute(ANSI)as an

ANSI/ASME or more sections of the ANSI/ASME

Boiler and Pressure Vessel code have been established as the

legal requirements in 47 states in the United States and in all

provinces of , in many other countries of the world,

the ASME Boiler and Pressure Vessel Code is used to construct

boilers and pressure zation of the ASME Boiler and

Pressure Vessel CodeThe ASME Boiler and Pressure Vessel Code

is divided into many sections, divisions, parts, and

of these sections relate to a specific kind of equipment and

application;others relate to specific materials and methods for

application and control of equipment;and others relate to care

and inspection of installed following Sections

specifically relate to boiler and pressure vessel design and

n ⅠPower Boilers(1 volume)

Section Ⅲ

Division 1Nuclear Power Plant Components(7 volumes)

Division 2Concrete Reactor Vessels and Containment(1

volume)

Code CaseCase 1 Components in Elevated Temperature

service(in Nuclear Code N-47

Case book)

Section Ⅳ Heating Boilers(1 volume)

Section Ⅷ

Division 1 Pressure Vessels(1 volume)

Division 2 Alternative Rules for Pressure Vessels(1 volume)

Section Ⅹ Fiberglass-Reinforced Plastic Pressure Vessels(1

volume)

A new edition of the ASME Boiler and Pressure Vessel Code

is issued on July 1 every three years and new addenda are issued

every six months on January 1 and July new edition of the

code becomes mandatory when it addenda are

permissive at the date of issuance and become mandatory six

months after that ide Pressure Vessel CodesIn

addition to the ASME Boiler and Pressure Vessel Code, which is

used worldwide, many other pressure vessel codes have been

legally adopted in various ulty often occurs when

vessels are designed in one country, built in another country, and

installed in still a different this worldwide

construction this is often the following list is a partial

summary of some of the various codes used in different countries:

AustraliaAustralian Code for Boilers and Pressure Vessels,

SAA Boiler Code(Series AS1200): AS1210, Unfired Pressure

Vessels and Class 1 H, Pressure Vessels of Advanced Design and

Construction, Standards Association of

Construction Code Calculation Rules for Unfired

Pressure Vessels, Syndicat National de la Chaudronnerie et de la

Tuyauterie Industrielle(SNCT), Paris,

KingdomBritish Code BS.5500, British Standards Institution,

London, apanese Pressure Vessel Code, Ministry

of LABOR, PUBLISHED BY Japan Boiler Association, Tokyo,

Japan;Japanese Standard, Construction of Pressure Vessels, JIS B

Gas Control Law, Ministry of International Trade and Industry,

published by The Institution for Safety of High Pressure Gas

Engineering , Tokyo, talian Pressure Vessel Code,

National Association for combustion Control(ANCC), Milan,

mCode for Good Practice for the Construction of

Pressure Vessels, Belgian Standard Institute(IBN), Brussels,

Swedish Pressure Vessel Code, Tryckkarls

Kommissioner, the Swedish Pressure Vessel Commission,

Stockholm, Sweden.(Selected from : and ,

Structural Analysis and Design of Process Equipment, John Wiley

& Sons Inc.,1984.)

阅读材料16

压力容器规范

美国压力容器规范从18世纪晚期到19世纪早期，锅炉和压力容器爆炸事故频发。186

5年4月27日发生在密西西比河上的一艘名为Sultana的轮船的火管锅炉爆炸事故，导致轮船在20分钟内沉没，船上载着的1500名从内战中准备回家的士兵死亡。类似的灾难在19世纪早期频发。1905年在马萨诸塞州的布罗克顿的一家鞋厂发生了一起严重的火管锅炉爆炸事故，造成58人死亡，117人受伤以及大约40万美元的损失。1906年，马萨诸塞州的林恩市的另一家鞋厂再次发生一起爆炸事故，同样造成了大范围的人员伤亡和财产损失。这起事故后，马萨诸塞州州长牵头成立了锅炉规范委员会。首部有关锅炉设计和建设的法律与1907年8月30日在马萨诸塞州颁布。这部法律有3页。

1911年，美国机械工程师学会(ASME)主席上校成立了一个委员会负责起草一部关于锅炉和压力容器的设计和建造的法律。1915年2月13日，首部ASME锅炉法规正式颁布。名为“《锅炉建造规范》1914版”。这部法规是繁杂的ASME锅炉与压力容器法规的开端，最终成为第一部分《动力锅炉》。

ASME关于压力容器的第一部法规叫做《无火压力容器的建造规范》，第八部，1925版。

3这部规范适用于直径超过6英寸、体积超过1.5ft、压力超过30帕的容器。1931年12月，一个名为APIASME联合委员会的组织组建了起来，目的是为石油工业编写无火的压力容器规范。最初的版本出现在1934年。接下来的17年，出现了两部独立的压力容器规范。1951年，最后一部独立的API-ASME规范得以颁布。1952年，这两部规范合并成一部-ASME无火压力容器规范，第八部。这部规范一直

沿用到1968版本出现。那时，最初的规范变为压力容器第八部，第一章，新的一部则是压力容器替代规范第八部，第二章。

ANSI/ASME锅炉和压力容器规范是美国机械工程学会在美国国家标准委员会(ANSI)的支持下作为ANSI/ASME文件颁布的。另有一部ANSI/ASME锅炉和压力容器规范作为法规已在美国的47个州和加拿大的所有省份实施。同样，在世界上许多其他国家，这部规范也被用来作为锅炉和压力容器建造的标准。

ASME锅炉和压力容器规范的组成ASME锅炉和压力容器规范分成许多部分、章节、子章节。其中的一些是关于特种设备的。其他事关于特种设备的的材料和使用方法以及控制，还有的是关于已安装好的设备的维护和检查。以下的章节是关于锅炉和压力容器的设计和建造的第一章 动力锅炉（1卷）

第三章

第一节核动力设备的组成（7卷）

第二节混凝土反应容器及其防漏（1卷）

标准容器《案例1 升温装置中的部件》（在核规范N-47案例书中）

第四章 加热锅炉（1卷）

第八章

第一节压力容器（1卷）

第二节 压力容器的替代规范（1卷）

第十章 玻璃纤维加强塑料容器（1卷）

每过三年的7月1日就会颁布一部新的ASME锅炉和压力容器规范，每六个月，即1月1日和7月1日就会有一部新的附录。新版本的规范颁布后就必须强制执行。新的附录在颁布之日起即可使用，并在六个月强制执行。

世界通用的压力容器规范除了ASME锅炉和压力容器规范在世界范围内被规范使用外，许多其他的压力容器规范也在世界其他国家依法使用。当压力容器的设计、制造、安装都在不同的国家时往往会出现问题。由于全球化的发展，这种事是经常发生的。

以下是在不同国家使用的不同规范的部分摘要：

澳大利亚澳大利亚锅炉与压力容器标准，SAA锅炉标准（AS1200系列）：AS1210，非火加热类压力容器和分类1H，改进后的设计与制造压力容器，澳大利亚协会标准。

法国《不用火加热压力容器建造规范计算规则》，法国巴黎市SNCT结构。英国《英国规范BS.55OO》，英国伦敦市英国标准协会。

日本《日本压力容器规范》（劳动部制定），日本东京市日本锅炉协会出版；JISB8243《日本标准》，《压力容器建造》，日本东京市日本标准协会出版；《日本高压气体控制法》，国际贸易与产业部制定，日本东京高压气体工程安全协会出版。

意大利《意大利压力容器规范》，意大利米兰市国家燃烧控制协会（ANCC）。

比利时《压力容器构造可靠实践规范》，比利时布鲁塞尔市比利时标准协会（IBN）。瑞典《瑞典压力容器规范》，瑞典斯德哥尔摩市瑞典压力容器委员会。