臥式蒸汽鍋爐結(jié)構(gòu)特點(diǎn)(WNS0.5-20T)

我公司生產(chǎn)的臥式蒸汽鍋爐采用為鍋殼式三回程、全濕背結(jié)構(gòu)。燃料在爐膽內(nèi)微正壓燃燒，高溫?zé)煔庋貭t膽向后經(jīng)回燃室進(jìn)入*煙道管束，經(jīng)壓迫式前煙箱轉(zhuǎn)折180°進(jìn)入第二管束，經(jīng)過(guò)對(duì)流換熱后排入大氣。
我們利用中心對(duì)稱的三回程結(jié)構(gòu)的設(shè)計(jì)思想，設(shè)計(jì)容量較大的三回程蒸汽鍋爐。這種鍋爐zui大的特點(diǎn)：所有的受壓元件與鍋筒中心對(duì)稱，鍋爐采用全濕背式結(jié)構(gòu)，以*的內(nèi)筒和偏心火箱的結(jié)構(gòu)，其有利于提供足夠的輻射受熱面。而對(duì)流受熱面有第二回程和三回程的管束構(gòu)成。回燃室前管板采用與爐膽連接，回燃室后管板采用橢球形封頭和管板。第二回程和第三回程轉(zhuǎn)煙室構(gòu)成了前煙箱，此出煙煙溫已低于500℃。因此，前煙箱的結(jié)構(gòu)采用輕形結(jié)構(gòu)的耐火保溫材料。后煙箱煙氣出口布置在沿筒體縱軸的方向，不僅可以縮短爐體長(zhǎng)度；又可以避免煙囪放在垂直于筒體縱軸線的方向上，在鍋爐啟動(dòng)停止時(shí)冷凝水腐蝕鍋爐本體。這種鍋爐的設(shè)計(jì)主要考慮了鍋爐檢修和穩(wěn)定的原則。鍋爐回水進(jìn)口內(nèi)設(shè)置的混水裝置，回水先沖刷煙管管束，再接觸爐膽，提高了回水接觸爐膽的水溫。避免了局部產(chǎn)生過(guò)冷沸騰的現(xiàn)象。爐水在燃燒煙氣高溫部分的下層，低溫在上部流動(dòng).就熱對(duì)流而言，已達(dá)到*的結(jié)構(gòu)設(shè)計(jì)。蒸汽鍋爐也達(dá)到zui大的汽化空間，加之后部加上隔板導(dǎo)致循環(huán)水流經(jīng)回燃室的高溫表面，使之合理均勻傳熱.確保回燃室的管板安全運(yùn)行。
（二） 波形爐膽（根據(jù)用戶的選擇）
本系列鍋爐采用波形爐膽，既強(qiáng)化了煙氣的擾動(dòng)，又增大了輻射傳熱面積；既增加了爐膽的剛度，又有效的減弱了爐膽的膨脹應(yīng)力；既增強(qiáng)傳熱效果，又促進(jìn)為燃料在爐膛內(nèi)的燃燒。
（三） 煙管與管板的焊接工藝
采用先預(yù)脹再全焊，然后再脹接的*工藝，既防止了管間隙腐蝕，又增強(qiáng)了焊接強(qiáng)度。
（四） 對(duì)稱活動(dòng)鉸接前、后煙門
開(kāi)啟方便，便于檢修，清理。
本系列鍋爐結(jié)構(gòu)緊湊，安裝運(yùn)輸方便。出廠前經(jīng)過(guò)熱態(tài)調(diào)試，不管在開(kāi)機(jī)率還是在運(yùn)行中都能穩(wěn)定運(yùn)行。本系列鍋爐配有進(jìn)口補(bǔ)水泵和燃燒器，全自動(dòng)程序控制，自動(dòng)化程度高。可使鍋爐達(dá)到*的燃燒效果。

二、臥式蒸汽鍋爐保護(hù)系統(tǒng)

<1>水位保護(hù)
蒸汽鍋爐配有二臺(tái)水泵，運(yùn)行和備用。
鍋爐配套一至二只板式水位計(jì)，應(yīng)經(jīng)常相互比較，發(fā)現(xiàn)指示不*的，須立即校正。水位計(jì)應(yīng)每班進(jìn)行沖洗，以確定其真實(shí)水位。同時(shí)還配有電極點(diǎn)水位平衡筒，可以準(zhǔn)確的采集水位信號(hào)以發(fā)出報(bào)警或進(jìn)行給水泵控制。
<2>壓力保護(hù)
a.蒸汽壓力保護(hù)
鍋爐壓力超過(guò)額定值時(shí)，需進(jìn)行連鎖保護(hù)：方法是停爐，燃燒系統(tǒng)停止工作；也可改變火嘴，單段或雙段燃燒，亦可調(diào)節(jié)油量，從而降壓，確保鍋爐安全運(yùn)行。
燃油(氣)蒸汽鍋爐壓力保護(hù)與水位一樣，采用多重保護(hù):
① 壓力控制器
一般用二個(gè)壓力控制器，將壓力信號(hào)轉(zhuǎn)化為電氣信號(hào)的機(jī)電轉(zhuǎn)換裝置，它的功能將壓力高、低不同的信號(hào)輸給電氣開(kāi)關(guān)，對(duì)外線路進(jìn)行自動(dòng)控制或連鎖保護(hù)。
常用壓力控制器及電接點(diǎn)壓力表，能使蒸汽壓力超壓報(bào)警，達(dá)到極*切斷燃燒器；壓力控制器根據(jù)實(shí)際運(yùn)行壓力調(diào)節(jié)單火或雙火燃燒；對(duì)于大型燃燒器，可根據(jù)壓力大小調(diào)節(jié)燃油量的大小，始終保持壓力穩(wěn)定運(yùn)行。
② 安全閥
安全閥是鍋爐保護(hù)中的zui后一道防線，在鍋爐壓力超過(guò)極*，根據(jù)安全閥設(shè)計(jì)所配的整定壓力，排汽泄壓，確保鍋爐正常運(yùn)行。
<3>溫度保護(hù)
溫度保護(hù)是鍋爐安全運(yùn)行過(guò)程中的重要程序，對(duì)于蒸汽鍋爐溫度的調(diào)節(jié)及保護(hù)尤為重要；同時(shí)在熱水鍋爐超溫時(shí)達(dá)到調(diào)節(jié)保護(hù)作用。鍋爐常用的溫度保護(hù)裝置為雙金屬溫度控制器
<4>熄火保護(hù)
　防止?fàn)t膛事件的發(fā)生，燃油（氣）鍋爐必須設(shè)置熄火保護(hù)裝置，功能是監(jiān)測(cè)爐膛內(nèi)燃燒情況（包括點(diǎn)火，當(dāng)點(diǎn)火失敗或燃燒中途熄滅時(shí)，一般在5秒內(nèi)重新點(diǎn)火，1秒鐘內(nèi)運(yùn)行，關(guān)閉進(jìn)油（氣）電磁閥，并接通和發(fā)出聲光報(bào)警信號(hào)，這時(shí)鼓風(fēng)機(jī)繼續(xù)運(yùn)轉(zhuǎn)，吹掃爐膛內(nèi)殘余的可燃?xì)怏w，經(jīng)過(guò)20～30秒鐘的吹掃后，自動(dòng)切斷鼓風(fēng)機(jī)及各種輔機(jī)電源，鍋爐停止運(yùn)行。）由火焰監(jiān)測(cè)器和控制裝置組成。火焰監(jiān)測(cè)器的作用是將控制裝置發(fā)出火焰存在或中斷的信號(hào)。
主要使用的是光電倍增管、光敏電阻和光電池，它們都有紫外型或紅外型，一種光電轉(zhuǎn)換元件，工作原理將光照輻射的強(qiáng)弱轉(zhuǎn)變成相應(yīng)的強(qiáng)弱電流。并呈線性狀態(tài)輸出，有時(shí)感應(yīng)電流弱，要通過(guò)放大，才能對(duì)控制器產(chǎn)生作用。
<5>停電自鎖保護(hù)
在突發(fā)電源中斷情況下，鍋爐運(yùn)行立即停爐自鎖，若電流恢復(fù)通電，隨時(shí)啟動(dòng)，必須復(fù)位解除自鎖，才能重新點(diǎn)火啟動(dòng)。

Structural characteristics of horizontal steam boiler
I produced horizontal steam boiler shell type three return all wet back structure. Slight positive pressure of fuel in the furnace tube combustion, high temperature flue gas along the furnace tube back to back to the combustion chamber into the first flue tubes, repressively before the smoke chamber turning 180 ° into the second bundle after convective heat transfer discharged into the atmosphere.
We use the centrosymmetric return structure design ideas, design capacity of the larger three-pass steam boiler. The greatest feature of this boiler: All pressure parts with the drum center of symmetry, boiler all wet back structure, with great inner cylinder and eccentric structure of the fire box, which may be useful to provide sufficient radiation heating surface. Convection heating surface constitute a second return and return the control. Back to the combustion chamber tube plate connection with the furnace tube, back to the combustion chamber tube plate with ellipsoidal head and tube sheet. The second return and the return transfer of smoke chamber before the smoke box, and this out of tobacco smoke temperature below 500 ℃. Therefore, before the structure of the smoke box with a light structure, fire-resistant insulation materials. After the smoke chamber gas outlet arranged in the direction of the longitudinal axis along the cylinder, not only can shorten the furnace length; also avoid the chimney on the direction perpendicular to the cylinder longitudinal axis of the corrosion of boiler condensate in the boiler starts to stop. The design of this boiler is mainly taking into account the principles of boiler maintenance and stability. Set of mixing with water in the boiler backwater imports devices, backwater first washed the smoke tube bundle, then contact the furnace tube, backwater contact with the water temperature of the furnace tube. To avoid local subcooled boiling phenomenon. Boiler water in the combustion flue gas high temperature part of the lower, the low temperature in the upper flow of thermal convection to achieve the best structural design. Steam boilers for maximum vaporization space, in addition to the rear plus partitions lead to high-temperature surface of the circulating water flow through back to the combustion chamber, so that it is reasonably uniform heat transfer. To ensure the safe operation of back combustion chamber tube plate.
(B) waveform furnace tube (depending on the user's choice)
This series of boiler waveform furnace tube not only strengthen the flue gas disturbance, increase the radiation heat transfer area; not only increasing the stiffness of the furnace tube, effectively weakening the swelling stress of the furnace tube; both to enhance the heat transfer effect, Also to promote the combustion of fuel in the furnace.
(C) of the smoke tube to tube sheet welding process
The first pre-expansion, all-welded, and the Expansion of advanced technology, both to prevent the tube gap corrosion, but also enhance the welding strength.
(D) symmetry activities articulated before and after the smoke door
Easy to open, easy to repair, clean-up.
The boiler in this series, compact structure, easy installation and transportation. Thermal debugging before delivery, regardless of the availability to run or in the operation can be stable. This series of boiler is equipped with imported fill pumps and burners, automatic control, high degree of automation. Enable the boiler to achieve optimal combustion.
Second, horizontal steam boiler protection system
<1> water level protection
The steam boiler is equipped with two pumps running and standby.
Supporting one to two boiler plate water level should always be compared with each other and found that the instructions are inconsistent, must be immediay corrected. Water level should be in each class to wash, to determine the true water level. At the same time the water level balance tube, comes with electrode point can be accuray collected water level signal to an alarm or pump control.
<2> pressure protection
(a) steam pressure protection
Boiler and pressure exceed the rated value, the need for chain protection: the method is shutdown, the combustion system to stop working; can also change the burner, single-stage or two-stage combustion can also adjust the fuel, in order to buck, to ensure the safe operation of boilers.
Fuel (gas) steam boiler and pressure protection and water level, the use of multiple protection:
① pressure controller
Generally two pressure controllers, pressure signals into electrical signals, mechanical and electrical conversion devices, it features high pressure, low signal loss to electrical switches, external circuits, automatic control or chain protection.
Commonly used pressure controllers and electric contact pressure gauge and make vapor pressure overpressure alarm limit is reached, cut off the burner; pressure controller is adjusted according to the actual operating pressure single fire or dual fire; for large burners, according to the size of the pressure regulator the size of the amount of fuel, and always maintain the pressure and stable operation.
② safety valve
The safety valve is the last line of defense in the boiler protection, the boiler pressure exceeds the limit, designed with safety valve set pressure, exhaust pressure relief to ensure the normal operation of the boiler.
<3> Temperature Protection
The temperature protection is an important process in the process of safe operation of boilers, steam boiler temperature regulation and protection is particularly important; reach adjust the protective effect of over-temperature hot water boiler. The boiler temperature protection device for a bimetallic temperature controller
<4> flame failure protection
To prevent the furnace incident boiler fuel (gas) must be set flameout protection device, the function is the monitoring of furnace combustion (including ignition, ignition, generally within 5 seconds when the ignition failure or extinguish burning halfway run within 1 second close into the oil (gas) solenoid valve, and switched on and the audible and visual alarm signal, when the blower continue to operate, purge the remnants of combustible gases in the furnace, and to automatically cut off the blower after 20 to 30 seconds to purge and a variety of auxiliary power supply, boiler stop running.) by the flame monitor and control devices. Flame detectors, control devices flame exists or interrupted signal.
The main use of photomultiplier tubes, the photoresistor and photovoltaic cells, they have a UV or infrared type, a photoelectric conversion element, the working principle of the light radiation intensity into the strength of the current. And linear state output, sometimes induced current is weak, by zooming in, in order to have an effect on the controller.
<5> blackout self-locking protection
In case of sudden power interruption, boiler operation immediay shutdown the self-locking, if the current recovery to power, start at any time, must be reset to lift the self-locking, in order to re-ignition start.