范文一:(一)线段射线直线的定义表示方法
11月?3日
?一:线段 ? 射线 ?直线
?(一):线?段 射线? 直线的?定义、表示?方法
?1、下图中?哪个是线段?,哪个是射?线,哪个是?直线,
?
?2、.图中?有____?____条?线段,__?_____?_条射线,?_____?___条直?线.
?
3、?过一点O可?以画几条直?线. ?
4?、过A、B?两点可以画?几条直线.?
? 5、经过?A、B、C?三点可以画?几条直线.?
6、?如图,在线?段AB上任?取D、C、?E三个点,?那么这个图?中共有几条?线段,
?
一:计?算题
1、?27?[(?,2)2+?(,4),?(,1)]? ? 2、 ?23,17?,(,7)?,(,16?)
? 二:比?较线段的长?短
1?、比较下列?各组线段的?长短
1)线段?OA与OB?. ?(
三?:角的度量?与表示
? (二)、?角的画法、?角的表示方?法
(?1)8:0?0时,时钟?的时针与分?针所成的角?度是___?__.
? (2)9?:00时,?时钟的时针?与分针所成?的角度是_?____.?
(3?)1:00?时,时钟的?时针与分针?所成的角度?是____?_.
?2、如图,?锐角的个数?共有___?____个?.
?二:化简下?列各式
? 1、?2(2a2?,9b),?3(,5a?2,4b)? ? ? ? ? 2、a,?(5a,3?b),(a?,2b) ?
? 3、3n?,[5n,?(3n,1?)] ? ? ? ? 4、a?,(5a,?3b),(?2b,a)?
?
?四:角的比?较
1?、一个周角?是一个平角?的____?_____?倍,一个平?角是一个直?角的___?_____?_倍.
? 五:平 ? 行
?(三)平行?线的画法、?表示方法
? 1、两?直线l1与?l2平行可?表示为__?_____?___. ? 2、过?_____?_____?作已知直线?的平行线,?能作且只能?作一条. ?三:先化简?,再求值
? 1、?(5a2,?3b2),?[(a2,?b2),(?5a2,3?b2)],?其中a,,?1,b,1?
?
? 六:垂? 直
? (四):?垂线的画法?、表示方法?
1、?过一点作已?知直线的垂?线,能作且?只能作__?_____?___条,?
?
?
范文二:(一)线段射线直线的定义`表示方法
11月3日
一:线段 射线 直线
(一):线段 射线 直线的定义、表示方法
1、下图中哪个是线段,哪个是射线,哪个是直线?
2、.图中有________条线段,________条射线,________条直线.
3、过一点O可以画几条直线.
4、过A、B两点可以画几条直线.
5、经过A、B、C三点可以画几条直线.
6、如图,在线段AB上任取D、C、E三个点,那么这个图中共有几条线段?
一:计算题
1、27÷[(-2)2+(-4)-(-1)] 2、 23-17-(-7)+(-16)
二:比较线段的长短
1、比较下列各组线段的长短
(1)线段OA与OB.
三:角的度量与表示
(二)、角的画法、角的表示方法
(1)8:00时,时钟的时针与分针所成的角度是_____.
(2)9:00时,时钟的时针与分针所成的角度是_____.
(3)1:00时,时钟的时针与分针所成的角度是_____.
2、如图,锐角的个数共有_______个.
二:化简下列各式
1、2(2a2+9b)+3(-5a2-4b) 2、a+(5a-3b)-(a-2b)
3、3n-[5n+(3n-1)] 4、a-(5a-3b)+(2b-a)
四:角的比较
1、一个周角是一个平角的_________倍,一个平角是一个直角的_________倍.
五:平 行
(三)平行线的画法、表示方法
1、两直线l1与l2平行可表示为__________.
2、过__________作已知直线的平行线,能作且只能作一条.
三:先化简,再求值
1、(5a2-3b2)+[(a2+b2)-(5a2+3b2)],其中a=-1,b=1
六:垂 直
(四):垂线的画法、表示方法
1、过一点作已知直线的垂线,能作且只能作__________条,
范文三:直线、射线、线段的表示方法
直线、射线、线段的表示方法
直线有两种表示法:一是用两个大写英文字母表示,读作直线AB或直线BA;二是用一个小写字母表示,直线AB也可记作直线l。
表示:直线 AB(或直线BA)
表示:直线 l l
长度。 探照灯射出的光线给我们以射线的形象,可从中抽象出射线概念:直线上某一点一旁的部分叫做射线。射线有一个端点,可以向一方无限延伸。射线也没有
射线用两个大写英文字母表示,第一个字母表示端点,第二个字母表示射线上任意一点,字母顺序不能颠倒。
如图,射线OA不能记作射线AO。
A 表示:射线 OA
射线可以向一方作反向延长线(如图3),延长射线AO或反向延长射线OA,延长部分不属于射线,常用虚线表示。
线段用表示它两个端点的字母或一个小写字母表示,有时这些字母也表示线段长度,记作线段AB或线段BA,线段a。
线段可以向两方无限延长,即延长线段AB或反向延长线段BA。
A B
表示:线段 AB(或线段BA)
表示:线段
a
范文四:阐述凝结水过冷度的定义和表示方法
阐述凝结水过冷度的定义和表示方法
2.1 定义
2.1 definitions
凝结水过冷度表征了凝汽器热水井中凝结水的过
度冷却程度,凝汽器热水井出口凝结水温度与凝汽器在
排汽压力下对应的饱和温度之差即称为过冷度。
Characterization of condensate supercooling degree are the overcooling of the condensate in the condenser hot well, the condenser hot well export water temperature and the condenser in the exhaust steam pressure corresponding to the saturation temperature difference that is referred to as the degree of supercooling.
2.2 表示方法
2.2 representation method
温度形式:
Temperature of the form:
δtn=ts-tc
The delta tn = ts - tc
式中:δtn—凝结水过冷度;
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Type: the delta tn - condensate supercooling degree;
ts—凝汽器绝对压力下的饱和温度;
Ts - condenser under the absolute pressure of saturated temperature;
tc—凝汽器热井中凝结水温度。
Tc - the condensate temperature in the condenser hot well.
3、过冷度产生的原因
3, the cause of supercooling degree
凝汽器运行中产生凝结水过冷却现象可能是凝汽
器设计中的问题,也可能是运行不当而产生的,一般主
要原因有以下几个。
Produced in the operation of the condenser condensate supercooled phenomenon may be a problem in the design of the condenser, also may be improper operation, generally has the following several main reasons.
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3.1 凝汽器内管束排列不好
3.1 within the condenser tube bundle arrangement is not good
在旧式结构的凝汽器上,凝结水过冷度可能很大。
这些凝汽器通常均为非回热式的,凝汽器内由于冷却水
管束布臵过密和排列不当,使汽气混合物在通往凝汽器
的管束中心和下部时存在很大的汽阻,引起凝汽器内部
绝对压力从凝汽器入口到抽气口逐渐降低,使得凝汽器
大部分区域的蒸汽实际凝结温度要低于凝汽器入口处
的饱和温度,形成了过冷度。这同时造成了蒸汽负荷大
部分集中在上部冷却管束处,蒸汽所凝结的水通过密集
的管束,又在冷却水管外侧形成一层水膜,又起到再冷
却凝结水的作用,加之排汽不能回热热水井中凝结水,
进一步加剧了凝结水的过冷却。
In the old structure of the condenser, the condensate supercooling degree could be large. The condenser is usually are not regenerative, condenser inside due to improper cooling water tube bundle arrangement too close and arrangement, make the steam gas mixture in the center of the tube bundle to the condenser steam and lower when there is a big resistance, absolute pressure inside a
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condenser from condenser inlet to the pump intake reduced gradually, makes much of the condenser of steam condensation temperature is lower than actual saturation temperature at the entrance of the condenser, formed the degree of supercooling. This caused a steam load at the same time mostly in the upper cooling tube bundle, steam
condensation water through dense bundles, and form a layer of water film on the outside of the cooling water pipe, also have the effect of cooling the condensate again, combined with the exhaust steam can't back to hot Wells in the condensate, further exacerbating the overcooling of the condensate.
3.2 空气漏入凝汽器或抽气器工作不正常
3.2 the air leakage into the condenser or ejector doesn't work properly
机组运行过程中,处于真空状态下的汽轮机的排汽
缸、凝汽器以及低压给水加热系统等部分,若有不严密
处,则会造成空气漏入;另一方面,抽气器工作不正常,
不能及时地把凝汽器内漏入的空气抽走。这两方面使得
凝汽器内积存的空气等不凝结气体增加,这不仅会在冷
却水管的表面形成传热不良的空气膜,降低传热效果,
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增加传热端差;同时还使得凝汽器内的汽气混合物中空
气成分的增高,造成空气分压提高、蒸汽分压降低,而凝
结水是在对应蒸汽分压的饱和温度下冷凝,所以此时凝
结水温度必然低于凝汽器压力下的饱和温度,因而产生
了凝结水的过冷却。
Unit operation in the process, under a vacuum of steam turbine exhaust cylinder, condenser and low pressure feed water heating system, if there are not tight, it will cause air leakage into the; Ejector work, on the other hand, is not normal, not in a timely manner to the condenser leak into the air. Accumulated within these two aspects makes the condenser of the air and condensation gas increases, this will not only on the surface of cooling water pipe form bad air heat transfer film, reduce the heat transfer effect, increase the heat transfer end difference; Also make the steam condenser in the higher gas mixture of air composition, increase caused by air pressure, steam partial pressure is reduced, and the condensate is in corresponding to the partial pressure of saturated steam condensing temperature,
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so at this point the condensate temperature must be lower than the saturation temperature of the condenser pressure, thus produced the overcooling of the condensate.
3.3 凝结水水位过高
3.3 the condensate water level is too high
运行过程中,由于凝结水泵真空部分漏入空气或其
它故障,使凝汽器热井中凝结水水位过高,淹没了下部
的冷却水管,这样冷却水又带走一部分凝结水的热量,
使凝结水再次被冷却,过冷度必然增大。
Operation process, because of the condensate pump vacuum part leak into the air or other fault, the condensate in the condenser hot well water level is too high, covered the bottom of the cooling water pipe, cooling water and take away part of the heat of the frozen water, make water is cooled again, degree of supercooling is bound to increase.
3.4 冷却水漏入凝结水内
3.4 cooling water leakage into the water
凝汽器内冷却水管破裂,造成冷却水漏入凝结水内,
使凝结水温度降低,过冷度增加,此时乳化液泵站还伴
有凝结水硬度增大的现象发生。
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Inside the condenser cooling water pipe burst, resulting in water leakage into the water, lower the water temperature, super-cooling degree increase, accompanied by the phenomenon of water hardness increase occurred at this time.
3.5 凝汽器冷却水入口温度和流量的影响
3.5 condenser cooling water inlet temperature and flow rate
现代 电站凝汽器通常为回热式的,具有合理设计
的管束结构,汽阻极小,在额定的设计工况下运行时,凝
结水过冷度实际可为零。在这种情况下,凝结水过冷度
主要受凝汽设备运行工况因素的影响,其中最重要的因
素是凝汽器冷却水的入口温度和流量。
Modern power plant condenser for regenerative, usually have a bundle structure of reasonable design, steam resistance small, under the design conditions of rated running, the condensate supercooling degree can be zero. In this case, the condensate supercooling degree is mainly influenced by condensing equipment operation condition factors, one of the most important factor is the condenser cooling water inlet temperature
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and flow rate.
试验与运行经验表明,在一定的蒸汽负荷下,当冷
却水入口温度降低或流量增加时,细石混凝土泵凝汽器
压力降低,真空增加,进入热井的凝结水的过冷度将增
大。
Test and operation experience show that under a certain load of the steam, when the cooling water inlet temperature decrease or increase traffic, condenser pressure, vacuum, in hot well of the condensate super-cooling degree will increase.
3.6 蒸汽负荷的影响
3.6 the influence of steam load
凝汽器蒸汽负荷的大小对凝结水过冷度也有一定
的影响。根据前苏联вти的试验结果,对于汽流向心
式凝汽器,随着蒸汽负荷的提高,过冷度增大;而对于汽
流向侧式凝汽器,蒸汽负荷升高时,过冷度减小。对于旧
式非回热式凝汽器,蒸汽负荷减小时,不可避免地会引
起过冷度增加。
Condenser steam load on the size of the condensate super-cooling degree has a certain influence. According to the former Soviet union kind guide т и test results, for steam flow to the heart
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type condenser, with the improvement of the steam load, super-cooling degree increased; For the steam flow to the lateral type condenser, steam load increases, the degree of supercooling. For old non regenerative condenser, steam load reduced, will inevitably cause super-cooling degree increase.
3.7 将温度较低的补充水直接补入凝汽器的热水
井
Add 3.7 will be added cooler water directly into the condenser hot well
机组在运行过程中,由于锅炉排污等原因,导致工
质在循环过程中产生了汽水损失,因此为了满足汽轮机
进汽量的需要,必须及时补入到汽水工质循环系统中。
补充水补入的位臵有除氧器和凝汽器两种方案,如果采
用补入凝汽器方案,冬天时补充水温度一般低于设计工
况时凝汽器中凝结水温度可达十几摄氏度。这样将温度
较低的补充水直接补入凝汽器的热水井,并且在补充水
流量较大时,势必会造成凝结水温度的降低,致使过冷
度增加。
Units in the process of operation, due to reasons such as boiler blowdown, cause working substance
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produced soda loss in the circulation process, so in order to meet the needs of the steam turbine inlet steam quantity, must add into the soda medium circulation system in a timely manner. Supplement water add the location of the deaerator and condenser coagulation two plans, if add condenser design, make-up water in winter temperature is lower than the design working condition of the condensate in the condenser temperature can be up to ten degrees Celsius. Such low temperature add supplementary water directly into the condenser hot well, and to supplement the water flow is big, will cause the condensate temperature is reduced, the supercooling degree increase.
4、过冷度对机组运行经济性和安全性的影响
4, the supercooling degree of impact on the economy and safety of the equipment operation
4.1 对机组运行经济性的影响
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4.1 impact on unit operation economical efficiency
凝汽器过冷度会增加冷源损失,引起作功能力的损
失,降低系统的热经济性。
Condenser supercooling degree can increase the cold source loss, cause the loss of work ability, reduce the thermal efficiency of the system.
通过对n15一4.9/470型汽轮机实例 计算 结果表
明,当凝结水过冷却度增加2?时,新蒸汽等效焓降减少
0.457kj/kg,机组效率相对降低0.051%,电厂标准煤耗
增加0.198g/kw.h。假设该机组年运行小时数为7500h,
那么,一台该型号机组每年多耗标煤为147.6t,相当于
每年多支出燃料成本3.1万元。可见,凝结水过冷度对
机组的经济运行有明显的影响,是一项不可忽视的指标,
因此采取各种措施降低凝结水过冷度是十分必要和有
意义的。
A 4.9/470 type steam turbine of n15 calculation results show that when the condensate supercooled degree increase 2 ?, the new steam to reduce 0.457 kj/kg of equivalent enthalpy drop, the unit efficiency relatively reduced 0.051%, the standard coal consumption of power plant by 0.198 g/kw. H. Assume that the unit annual operation hours is 7500
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h, so, one the model units annually more BiaoMei consumption is 147.6 t, equivalent to more than a year spending on fuel costs 31000 yuan. Visible, the condensate supercooling degree has distinct effect on the economic operation of the unit, cannot be ignored is an indicator, so to take various measures to reduce the condensate supercooling degree is very necessary and meaningful.
4.2 对机组运行安全性的影响
4.2 impact on unit operation safety
凝结水过冷度的存在会威胁机组运行的安全性和
可靠性。凝结水温度过低,即凝结水水面上的蒸汽分压
力的降低,气体分压力的增高,使得溶解于水中的气体
含量增加,因为溶于凝结水的气体量和热井水面上气体
的分压力成正比。因此若凝结水出现过冷度,则其含氧
量增加,这将导致凝汽器内换热管、低加及相关管道阀
门腐蚀加剧,以致降低设备的使用寿命,不利于机组的
安全运行。这同时也加重了除氧器的工作负担,使除氧
器的除氧效果变差,严重时会腐蚀处于高温工作环境下
的给水管道和锅炉省煤器管,引起泄漏和爆管。据统
计,2003年某电厂凝汽器冷却水管腐蚀造成的泄漏,使
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凝结水硬度超标,迫使机组降低出力带负荷查漏次数多
达5次。可见,凝结水过冷度的存在对机组运行安全性
极为不利。
The condensate supercooling degree there will endanger the safety and reliability of the equipment operation. Condensation water temperature was low, the partial pressure of the steam condensate water, gas partial pressure increases, made the gas dissolved in the water content increases, because in the condensate gas amount and hot well water surface is directly proportional to the partial pressure of the gas. So if appears condensate supercooling degree, the oxygen content increases, this will lead to the condenser heat exchange tube, low corrosion intensifies and related pipeline valve, so as to reduce the service life of equipment, is not conducive to the safe running of the unit. It also adds to the deaerator's work burden, make the deaerating effect of deaerator, serious corrosion at high temperature when they work under the environment of water supply pipes and boiler
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economizer tubes, leakage and detonation tube. According to statistics, in 2003 a certain power plant condenser cooling water pipe corrosion caused by the leak, the water hardness is high, forcing the crew cut output loading leak frequency up to 5 times. Visible, the existence of condensate supercooling degree of unit operation to the detriment of security.
5、减少凝结水过冷度的对策
5, to reduce the condensate supercooling degree of countermeasures
通过上述对凝结水过冷度产生原因及其对机组运
行经济性和安全性的影响的分析可以看到,凝结水过冷
度的存在威胁着机组运行的安全性和可靠性,同时也会
降低机组运行的经济性。因此须从设计、改造、检修以
及运行维护等各个环节对其采取有效措施,以期降低凝
结水过冷度,提高机组运行的经济性和安全性。
By the above reasons of condensate supercooling
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degree and its effect on the running efficiency and security analysis can see, the condensate supercooling degree of the existence of the threat to the safety and reliability of the equipment operation, also can reduce the running efficiency. So must be from the design, modification, maintenance, and operation maintenance and so on each link to take effective measures, in order to reduce the condensate supercooling degree, improve the economic benefit of unit operation and safety.
5.1 设计中所采取的对策
5.1 design countermeasures taken in
(1)在冷却水管束设计中改进管束的布臵,在管束
结构中适当留有足够宽的蒸汽通道,这除了可以保证汽
流均匀进入管束各区域外,还可保证部分排汽可直接通
至凝汽器底部,以加热凝结水,减少凝结水过冷度;同时
应使抽气口位臵离开凝结水远一些,以减少凝结水过冷
度;
(1) the improvement in the design of cooling water tube bundle tube bundle arrangement, proper in the vascular bundles have enough wide steam channel, in addition to this can ensure uniform steam flow
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into the tube bundle district outside, still can ensure some exhaust steam can pass directly to the condensing objects bottom, heating water, reduce the condensate supercooling degree; Also should make the bleeding point location away from the condensate far away, in order to reduce the condensate supercooling degree;
(2)从凝汽器入口至抽气口的路径应力求直接,且
有足够的流通面积,蒸汽进入管束的流速不超过
40m/s,50m/s,蒸汽沿程阻力尽量小,以减少汽阻,降低
凝结水的过冷度;
(2) from the condenser to the path of the entrance to the suction port directly, and have enough circulation area, the flow rate of the steam into the tube bundle is not more than 40 m/s ~ 50 m/s, steam on-way resistance small, as far as possible to reduce the steam resistance, reduce the condensate supercooling degree;
(3)合理选择凝汽器内的淋水装臵,优化设计循环
冷却水量;
(3) selection of condenser in the water spray device, the optimal design of circulating cooling
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water;
(4)汽轮机排汽口与凝汽器的连接采用柔性连接,
以防止运行中膨胀不畅导致空气的漏入;
(4) the exhaust mouth connected to the condenser of the steam turbine adopts flexible connection, in order to prevent confusing cause air leakage into the operation of inflation;
(5)对于排入凝汽器的各种疏水、补充水、再循环
水及其它附加流体,接至凝结器的位臵一定要高于凝结
水水位,最好接至凝结器上部蒸汽空间,并装折流档板,
防止冲刷冷却水管,以除掉这些水源中的空气,减少对
凝结水溶氧及对过冷度的影响;
(5) for into the condenser of hydrophobic, replenish water and circulating water and other additional fluid, connect to the location of the condenser must be higher than that of the condensate water level, the best upper connected to the condenser steam space, and baffle plate,
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to prevent scour cooling water pipe, in order to get rid of the water in the air, to reduce across cold water dissolved oxygen and the degree of influence;
(6)利用锅炉连续排污对补充水进行加热,以减少
补入凝汽器的补充水对凝结水的过冷却。一般凝汽器的
补充水箱与除氧器、连续排污扩容器布臵在同一平台处,
因此可在补充水箱内加装一组管式换热器,由连续排污
扩容器引出一管,将排污水送入换热器中作为热源,(下
转76页)(上接75页)以加热补充水,然后再排入地沟。
(6) using the boiler continuous sewage for make-up water for heating, in order to reduce the added water add condenser overcooling of the condensate. General additional tank condenser and deaerator, continuous blowdown flash tank arranged on the same platform, thus can supplement the tank equipped with a set of pipe heat exchanger, the continuous blowdown flash tank raises the tube, the domestic sewage as heat source, heat exchanger into in turn (page 76) (on page 75) supplemented by heating the water, and then into the gutter.
5.2 改造中所采取的对策
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5.2 reform countermeasures taken in
旧式凝汽器通常均为非回热式的,冷却管束通道很
窄,汽阻很大,可达1.3,2.0 kpa,这本身就可使过冷度
达到5?,10?。对于这些老式凝汽器,凝结水过冷度与
工况因素几乎无关,消除这种过冷现象唯一有效的措施
是改造凝汽器冷却管束结构。如:
Old condenser are usually non regenerative, cooling tube bundle channel is very narrow, steam resistance is very big, can reach 1.3 ~ 2.0 kpa, that in itself can make the supercooling degree reach 5 ? to 10 ?. For these old condenser, the
condensate supercooling degree has little to do with working condition, eliminate the supercooling phenomenon is the only effective measures to transform the condenser cooling tube bundle structure. Such as:
(1)拆除一部分冷却水管(减少一部分冷却面积),
让排汽可深入到冷却面中部,并留有足够的宽度,但不
穿通,使蒸汽能沿着冷却面作均匀的分配,并使凝结水
加热到排汽温度;
Part (1) the demolition of part of the cooling water pipe (reduce cooling area), allow the exhaust steam
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into the central cooling surface, and had enough width, but not through, can make steam along the cooling surface of the uniform distribution, and makes the water heated to steam discharge temperature;
(2)在冷却管束中合理布臵一些集水、排水元件;
(2) in the cooling bundles reasonable decorate some catchment and drainage element;
(3)限制管束中汽流流速,使其尽可能不超过
40m/s,50m/ s。
(3) bundle ZhongQi flow velocity, so that it is not as much as possible for more than 40 m/s ~ 50 m/s.
5.3 检修中所采取的对策
5.3 maintenance countermeasures taken in
(1)对真空系统进行灌水查漏,重点检查凝汽器喉
部、低压抽汽管路、低压缸轴封蒸汽进出管道焊口、低
压缸法兰接合面、热井焊接处、凝结水管道法兰连接处、
凝汽器水位计接头处、疏水扩容器焊接处、与热井连接
的真空系统阀门等部位,并修补泄漏处;
(1) the vacuum system for water leak, check the condenser throat, low pressure steam extraction
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pipe, low pressure cylinder in and out of the pipe joint and low pressure shaft seal steam cylinder flange joint surface, thermal Wells, condensate pipeline flange joint welds, condenser water level gauge, joint drain flash tank welding, vacuum system, which is connected with hot well valve and other parts, and repair the leak;
(2)检查凝汽器内的淋水装臵;
(2) check the tube in the condenser water device;
(3)对凝汽器水位调节器和轴封压力调节器进行检
修;
(3) the regulator and shaft seal water level in the condenser pressure regulator for maintenance;
(4)对抽真空系统进行检修,保证抽气设备的正常
工作,以便运行时可及时抽出凝汽器内不凝结气体。
(4) the vacuum system for maintenance and repair, the normal work of the extraction equipment, so that the runtime can timely take out inside the condenser condensate gas.
5.4 运行中所采取的对策
5.4 in the operation of the adopted countermeasures
5.4.1 保证真空部分的严密性
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5.4.1 ensure vacuum rigor
保证真空部分的严密性,防止空气漏入,同时正确
配臵抽气器。这不仅是为了维持凝汽器内的高真空度,
也是防止凝结水过冷的有效措施之一。投运行轴封压力
调节器,并将轴封压力控制在规定值内,以防止空气从
轴封漏入,影响凝汽器真空。
Ensure part vacuum rigor, prevent leakage into the air, at the same time correct configuration of ejector. This is not only to maintain a high vacuum degree within the condenser, it is also one of the effective measures to prevent condensate supercooling. Run for shaft seal pressure regulator, and shaft seal pressure control within the specified value, in order to prevent the air from the shaft seal leakage, affect the condenser vacuum.
5.4.2 对凝结水水位及水质的监视与控制
5.4.2 of condensate water level and water quality monitoring and control
为了消除运行中凝结水水位过高而造成的凝结水
过冷却现象,一方面除了要求运行人员对凝结水水位严
格监督外,另一方面可通过装设凝结水水位自动调节器
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和报警装臵,使凝结水水位保持在正常范围内。同时,还
可以利用凝结水泵本身的运行特性,采用凝汽器低水位
运行的方式。
In order to eliminate the condensate in the operation of the condensate supercooled phenomenon caused by water level is too high, on the one hand, in addition to the required operating personnel to the condensate water outside the strict supervision, on the other hand can furnish the condensate water automatic regulator and alarm devices, and keep the water level in the normal range. At the same time, still can use the running characteristic of condensate pump itself, adopt the condenser low water level operation.
运行中凝汽器冷却水管腐蚀泄漏,会引起凝结水硬
度超标,过冷度增大。若水质超标不严重,可在循环水入
水口处放入木糠堵漏;若水质超标严重,则采取运行中
降负荷半边凝汽器查漏方法堵漏或停机时堵漏。
In the operation of the condenser cooling water pipe corrosion leakage and will cause excessive water hardness, super-cooling degree increased. If the water quality of paint is not serious, but
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in the circulating water entry into the wood chaff plugging; If water quality exceeds bid badly, take in the operation of the load down half the condenser leakage inspection method plugging or when stop leakage.
5.4.3 对冷却水的流量和入口温度调节和控制
5.4.3 the cooling water flow rate and inlet temperature regulation and control
冬季冷却水温较低时,为了消除或尽量减小凝结水
过冷度并节约厂用电,应减小冷却水流量。当循环冷却
水泵采用母管制连接时,可通过改变运行的水泵台数或
者关小压力管道上的阀门来调节冷却水流量。如果循环
冷却水泵采用单元制配臵,需通过改变水泵工作叶片旋
转角度来调节出力,或用改变电动机电极对的数目以改
变转速来改变出力,或通过改变循环冷却水泵的工作台
数来调节出力。对于具有空气冷水塔的机组,可通过调
整运行中的多级变速风机的速度和和数量来控制冷却
水温度,调节冷却水流速以获得零过冷度。
Cooling water temperature in winter is low, as far as possible in order to eliminate or reduce the condensate supercooling degree and save auxiliary power, should decrease the cooling water flow rate.
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When circulating cooling water pump USES the mother tube connection, but by changing the operation of the pump stations or turn down pressure valve to adjust cooling water flow in the pipeline. If use unit system configuration, the circulating cooling water pump need to work by changing the water pump vane rotation Angle to adjust output, or use the electrodes to change motor to change speed to change the number of output, or by changing the circulating cooling water pump work stations to adjust the output. For unit with air cooling tower, fan speed can be adjusted by running multiple variable speed and quantity and to control the cooling water temperature, adjusting the cooling water flow rate to achieve zero supercooling degree.
范文五:水分和湿度的定义及表示方法
ertuiop
水分和湿度的定义及表示方法
一般将空气或其他气体中的水分含量称为湿度,将固体物质中的水分含量成为含水量。湿度和含水量是工业生产和农业生产的重要参数,也是生产环境条件的重要指标。
1.气体的湿度
空气和其他气体的湿度可用以下方法表示。
(1)绝对湿度
在一定温度及压力条件下,每单位体积混合气体中所含的水蒸气量,单位为 g /m3 。
(2)相对湿度
单位体积混合气体中所含的水蒸气量与同温度下饱和水蒸气量的比值的百分数,一般用符号RH表示,饱和水蒸气量是指在一定温度下,单位体积的气体中所能含有的最大水蒸气量。
2.固体的湿度
固体的湿度也称为含水量,通常以物质中所含水分质量(或重量)与总质量(或总重量)纸币的百分数来表示。
一般將空氣或其他氣體中的水分含量稱為濕度,將固體物質中的水分含量成
ertuiop
為含水量。濕度和含水量是工業生產和農業生產的重要參數,也是生產環境條件的重要指標。
1.氣體的濕度
空氣和其他氣體的濕度可用以下方法表示。
(1)絕對濕度
在一定溫度及壓力條件下,每單位體積混合氣體中所含的水蒸氣量,單位為 g /m3 。
(2)相對濕度
單位體積混合氣體中所含的水蒸氣量與同溫度下飽和水蒸氣量的比值的百分數,一般用符號RH表示,飽和水蒸氣量是指在一定溫度下,單位體積的氣體中所能含有的最大水蒸氣量。
2.固體的濕度
)與總質量 固體的濕度也稱為含水量,通常以物質中所含水分質量(或重量(或總重量)紙幣的百分數來表示。
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