為了保證柴油機壓縮空氣起動迅速可靠,必須具備以下三個條件:
(1)壓縮空氣必須具有一定的壓力和儲量;
(2)壓縮空氣供氣要適時并有一定的供氣延續(xù)時間;
(3)必須要保證有最少氣缸數(shù)。
2、壓縮空氣起動裝置的主要設備
(1)氣缸起動閥
氣缸起動閥是起動裝置中最主要的部件之一。通常,每缸一個均裝在氣缸蓋上,其下方與起動空氣總管連接,上方與空氣分配器連接。其動作由空氣分配器按發(fā)火順序使起動空氣進入氣缸,完成起動動作。
氣缸起動閥分為單向閥式和氣壓控制式兩種。前者為一個簡單的單向閥,其起動空氣與控制空氣合并由空氣分配器控制。后者,開閥的控制空氣與進入氣缸的起動空氣分開輸送。
(2)空氣分配器
空氣分配器由凸輪軸驅(qū)動。它的作用是按照柴油機的發(fā)火順序,在要求的起動正時時刻內(nèi)將控制空氣分配器到相應的氣缸起動閥使之開啟,讓壓縮空氣進入氣缸,起動柴油機。
(3)主起動閥
主起動閥是壓縮空氣系統(tǒng)的總開關,用來起閉空氣瓶至空氣分配器和氣缸起動閥間的主起動空氣通路;在起動操縱時來自空氣瓶的壓縮空氣經(jīng)主起動閥迅速進入起動空氣總管,并經(jīng)總管分至各缸氣缸起動閥和空氣分配器,使啟動迅速可靠并減少壓縮空氣的節(jié)流損失;當啟動完畢后,它能迅速切斷進入起動總管的壓縮空氣,并使總管中的殘余空氣經(jīng)主起動閥進入大氣。因此,在大、中型柴油機壓縮空氣起動裝置中多設有主起動閥。
3、壓縮空氣起動系統(tǒng)常見故障分析
(1)柴油機不能起動
當起動手柄或手輪推至起動位置時,如果柴油機沒有轉(zhuǎn)動,其主要原因在起動系統(tǒng)。可能的原因有以下幾個方面:
① 盤車機未脫開,起動控制空氣處于關閉狀態(tài);
② 空氣瓶出口閥或主截止閥未開足;
③ 起動空氣壓力不足;
④ 起動空氣管系臟污,空氣流量不足;
⑤ 起動空氣系統(tǒng)中的有關閥件,如主起動閥、起動控制閥、空氣分配器、氣缸起動閥
等卡死、磨損、漏氣。
(2)起動時曲軸轉(zhuǎn)動但達不到發(fā)火所需的轉(zhuǎn)速
可能的原因和解決的辦法如下:
① 起動空氣壓力太低,應予補充;
② 柴油機暖缸不足,滑油粘度太大,應予暖缸;
③ 起動操縱過快,應重新起動;
④ 個別氣缸起動閥或空氣分配器咬死或動作不靈活,應檢查、拆卸清洗。
(3)某一段起動空氣管發(fā)熱
通常是該缸起動閥泄漏所致。應檢修漏氣的起動閥。
二、柴油機換向裝置
換向裝置常見故障分析:
屬于換向機構的故障有:
① 換向機構中有閥件咬死;
② 換向伺服器故障:堵塞、漏油、轉(zhuǎn)板在極端位置咬死或不能到達另一極端位置;
③ 空氣分配器故障。
屬于操作不當?shù)挠校?/P>
① 操作過快,凸輪軸尚未到位就急于起動使換向失??;
② 換向手柄雖已到位,但由于水流作用使螺旋槳仍按原轉(zhuǎn)向以較高轉(zhuǎn)速轉(zhuǎn)動,此時急
于起動而使換向失敗;
③ 在緊急剎車時,過于性急,強制制動的時機不當,使轉(zhuǎn)向失敗。
三、柴油機調(diào)速器的故障分析
當柴油機在工作中轉(zhuǎn)速變化出現(xiàn)異常時,通常應考慮以下三個方面的因素:柴油機工
作性能惡化;調(diào)速器某些輔助設備失常;調(diào)速器本身失常。因此,應首先進行以下檢查:
(1)確認柴油機的負荷是否超出了柴油機的標定負荷;
(2)檢查各缸的負荷是否嚴重的不均,是否正常發(fā)火,噴油器是否處于正常的工作狀態(tài);
(3)檢查調(diào)速器與噴油泵之間的杠桿傳動機構是否卡滯和間隙過大而松動;
(4)檢查調(diào)速器負荷指針的零位與噴油泵的零位是否一致;
(5)檢查調(diào)速器的設定機構、控制空氣壓力是否正常。
當進行以上檢查并排除后,如調(diào)速器工作仍然不正常,則為調(diào)速器的自身故障,這些故障通常有:
1、柴油機游車或轉(zhuǎn)速振蕩
游車指轉(zhuǎn)速有節(jié)奏地變化,以手動停住調(diào)速器的作用時可以消除,但放手后仍會有節(jié)奏的轉(zhuǎn)速變化。轉(zhuǎn)速振蕩指轉(zhuǎn)速有節(jié)奏變化且幅度較大,手動停住調(diào)速器作用可消除波動,放手后轉(zhuǎn)速不會立即重新波動,但在調(diào)速或負荷變化后波動仍會發(fā)生,可能的原因有:
(1)調(diào)速器反饋系統(tǒng)調(diào)速不當,應重新進行穩(wěn)定性調(diào)節(jié);
(2)調(diào)油桿、高壓油泵空動或卡死;
(3)調(diào)速器滑油太臟、起泡或油位太低(油位表不見油位);
(4)調(diào)速器內(nèi)部故障,如飛重和軸承磨損、滑閥卡死、補償(阻尼)彈簧彈性失效等;
(5)調(diào)速器與柴油機不匹配。
2、調(diào)速器輸出軸顫動(高頻振動)
可能的原因有:
(1)調(diào)速器驅(qū)動不穩(wěn)。如傳動齒輪磨損、嚙合不良、凸輪軸傳動機構松動、柴油機減振器故障等;
(2)飛重的彈性驅(qū)動機構故障;
(3)調(diào)速器在安裝支座上沒有均勻緊固。
3、柴油機達不到全速全負荷
可能的原因有:
(1)噴油泵齒條拉出長度不夠或調(diào)速器輸出軸已達到最大輸出行程(刻度10)。這可能是由于調(diào)油桿系卡滯、空動,調(diào)速器輸出軸與噴油泵供油刻度匹配不當?shù)纫蛩匾穑?/P>
(2)控制空氣或掃氣空氣壓力太低或設定轉(zhuǎn)速太低;
(3)動力活塞運動受阻;
(4)液壓系統(tǒng)油壓過低或油路堵塞。
4、柴油機起動時高壓油泵齒條不能及時拉開
可能的原因有:
(1)調(diào)速器中油壓低,如齒輪泵磨損、齒輪泵單向閥泄漏;
(2)起動轉(zhuǎn)速太低;
(3)升壓伺服器(在起動時刻使用起動空氣迅速增加調(diào)速器內(nèi)滑油壓力的選用設備)動作不佳;
(4)某種斷油機構(如停車螺帽等)調(diào)整不當;
(5)轉(zhuǎn)速設定值或掃氣壓力燃油限制器(在起動時由掃氣壓力限定調(diào)速器輸出軸轉(zhuǎn)角的一種輔助裝置)設定值太低。
Frugality of speed control system and control system of diesel engine
A diesel engine starter
Diesel engines under the forces for air intake, compression, injection, combustion until fuel runs silently expansion work, which
According to a process of diesel engine starting. Starting speed of general scope are:
High speed diesel engine 80~150 r/min; 60~70 r/min medium speed diesel engines; low-speed diesel engine 25~30 r/min.
1, the composition and working principle of compressed air Starter
Compressed air Starter is a certain pressure of compressed air, diesel engines introduced when the expansion stroke cylinder in the firing order, promote the piston to make diesel engines meet the starting speed, complete the firing on their own.
In order to ensure speedy and reliable diesel engine compressed air starter, you must meet the following three conditions:
(1) compressed air must have a certain amount of pressure and reserves;
(2) the compressed air supply to duration and there is a certain amount of gas supply in due time;
(3) the need to ensure that at least the number of cylinders.
2 major equipment, compressed air Starter
(1) the cylinder valve
Cylinder valve is one of the most important parts in the starter. Typically, each cylinder mounted on a cylinder head, beneath it with starting air duct connection, connect with air Distributor at the top. Their movements by the air distributor firing order for starting air into the cylinder, complete starting action.
Starting valve cylinder divided into valves and pressure control in two ways. The former is a simple one-way valve, its starting air merged with controlled air is controlled by air Distributor. The latter, open control valve separate starting air conveying of air and into the cylinder.
(2) air distributor
Air distributor driven by the camshaft. Its role is in the diesel engine firing order, at the request of the starting time will be control air distributor to the appropriate cylinder valve to make it open, let compressed air into the cylinder, starting diesel engines.
(3) main starting valve
Main since dynamic valve is compression air system of total switch, used to since closed air bottle to air Distributor and cylinder since dynamic valve between of main since dynamic air pathway; in since dynamic manipulation Shi from air bottle of compression air by main since dynamic valve quickly entered since dynamic air duct, and by duct min to the cylinder cylinder since dynamic valve and air Distributor, makes started quickly reliable and reduced compression air of throttle loss; Dang started finished Hou, it can quickly cut off entered since dynamic duct of compression air, and makes duct in the of residual air by main since dynamic valve entered atmospheric. Therefore, in large and medium diesel engine compressed air Starter has the primary valve.
3, compressed air brake system trouble analysis
(1) diesel engine not start
When the starting handle or push the handwheel to start position, if the diesel engine is not turning, the main reasons in the starting System. Possible reasons are the following aspects:
① Turning does not disengage, starting control of air in a closed state;
② air cylinder outlet valve or the main stop valve was not full;
③ insufficient starting air pressure;
④ starting air pipe dirt, lack of air flow;
⑤ starting air about valves in the system, such as the main starting valve, control valve, air Distributor, the cylinder valve
Card dead, damaged and leakage.
(2) the crankshaft rotation when starting but does not meet the required for the combustion speed
Possible causes and solutions are as follows:
① starting air pressure is too low and should be supplemented;
② diesel engine warm-cylinder insufficient lubricating oil viscosity is too large and should be warm-cylinder;
③ Start manipulating too quickly and should be starting afresh;
④ individual cylinder valve or air distributor bitten to death or the action is not flexible, you should check and removal of cleaning.
(3) a period of starting air pipe heating
Is usually caused by leakage of the valve from the cylinder. Starting valve leakage inspection and repair.
Second, diesel engine reversing device
Common fault analysis of commutation device:
Belonging to the reversing gear failures are:
① reversing valves of the bodies killed;
② commutation server failure: plug, oil spills, transfer Board, or bitten to death in extreme locations cannot reach the other extreme position;
③ Air distributor fault.
Belonging to the improper operation of:
① actions too quickly, camshaft is not yet in place is eager to start making your reversal fails;
② the reversing handle has in place, but because of the steady flow by the propeller on an original shift to high speed rotation, acute
On commutation failure as a Starter;
③ When the emergency brakes, too impatient, inappropriate timing of forces the brake, causing the steering to fail.
Third, speed Governor of diesel engine fault analysis
Engine speed changes when an exception occurs in the work, typically you should consider the following three factors: diesel
Performance deterioration of Governors of certain auxiliary equipment malfunction; Governor disorder in itself. Therefore, you should first check the following:
(1) confirm that the diesel engine load beyond the calibration of diesel engine load;
(2) check whether the load each cylinder serious inequality, whether normal combustion, fuel injector is in good working condition;
(3) check the Governor with fuel injection pump lever actuator is stuck between-delay and gap too large and loose;
(4) check the Governor load pointer to zero-zero digits are consistent with the injection pump;
(5) checks whether a Governors constituted body, control of air pressure is normal.
When you make these checks and after excluding, as Governor is still not working properly, the Governor's own fault, these failures usually are:
1, traveling or diesel engine speed oscillation
Traveling speed changes in rhythm, to manually stop Governor's role can be eliminated, but is let go after rhythmic speed changes. Speed oscillation means rhythm changes in speed and range is large, manually stop Governor eliminates fluctuations, fluctuations in speed does not immediately after letting go, but after the changes in speed or load fluctuations may occur, possible causes are:
(1) the Governor feedback system speed properly renewed stability should be adjusted;
(2) adjustable rod, high pressure pumps air or blockage;
(3) the Governor oil too dirty, bubbles or oil level is too low (see oil level oil level table);
(4) internal fault of Governors, flies and bearing wear, sliding valves stuck, compensation (damping) elasticity of spring invalidation;
(5) the Governor with diesel engines do not match.
2, speed of the output axis quiver (high-frequency vibrations)
Possible reasons are:
(1) the Governor-driven instability. Transmission gear worn loose, poor meshing, camshaft gear, engine shock absorber failure;
(2) flexible drive mechanism failure on the fly;
(3) the Governor does not have the install pedestal tighten evenly.
3, diesel engines are not up to full speed at full load
Possible reasons are:
(1) pull the fuel pump racks length is insufficient to trip the Governor output shaft or has reached the maximum output (scale of 10). This may be due to oil linkage block, air motion, Governor output shaft and injection pump oil supply caused by improper matches the scale factor;
(2) controlling air or scavenge air pressure too low or set speed is too low;
(3) the power piston is blocked;
(4) hydraulic system pressure too low or the oil plug.
4, when the diesel engine starting fuel pump wires can not be timely opened
Possible reasons are:
(1) the Governor oil pressure, such as gear pump wear, gear pump check valve leaks;
(2) starting speed is too low;
,, , , (3) boost server (at starting point using the rapid increase in the starting air Governor selection of lubricating oil pressure equipment in) poor actions;
(4) a certain oil bodies (such as stopping nuts) improper adjustments;
(5) speed settings or scavenge pressure fuel limiter (at the time of starting qualified by a sweep gas pressure Governor output shaft rotation of an assistive device) set value is too low. Frugality of speed control system and control system of diesel engine
A diesel engine starter
Diesel engines under the forces for air intake, compression, injection, combustion until fuel runs silently expansion work, which
According to a process of diesel engine starting. Starting speed of general scope are:
High speed diesel engine 80~150 r/min; 60~70 r/min medium speed diesel engines; low-speed diesel engine 25~30 r/min.
1, the composition and working principle of compressed air Starter
Compressed air Starter is a certain pressure of compressed air, diesel engines introduced when the expansion stroke cylinder in the firing order, promote the piston to make diesel engines meet the starting speed, complete the firing on their own.
In order to ensure speedy and reliable diesel engine compressed air starter, you must meet the following three conditions:
(1) compressed air must have a certain amount of pressure and reserves;
(2) the compressed air supply to duration and there is a certain amount of gas supply in due time;
(3) the need to ensure that at least the number of cylinders.
2 major equipment, compressed air Starter
(1) the cylinder valve
Cylinder valve is one of the most important parts in the starter. Typically, each cylinder mounted on a cylinder head, beneath it with starting air duct connection, connect with air Distributor at the top. Their movements by the air distributor firing order for starting air into the cylinder, complete starting action.
Starting valve cylinder div, ided into valves and pressure control in two ways. The former is a simple one-way valve, its starting air merged with controlled air is controlled by air Distributor. The latter, open control valve separate starting air conveying of air and into the cylinder.
(2) air distributor
Air distributor driven by the camshaft. Its role is in the diesel engine firing order, at the request of the starting time will be control air distributor to the appropriate cylinder valve to make it open, let compressed air into the cylinder, starting diesel engines.
(3) main starting valve
Main since dynamic valve is compression air system of total switch, used to since closed air bottle to air Distributor and cylinder since dynamic valve between of main since dynamic air pathway; in since dynamic manipulation Shi from air bottle of compression air by main since dynamic valve quickly entered since dynamic air duct, and by duct min to the cylinder cylinder since dynamic valve and air Distributor, makes started quickly reliable and reduced compression air of throttle loss; Dang started finished Hou, it can quickly cut off entered since dynamic duct of compression air, and makes duct in the of residual air by main since dynamic valve entered atmospheric. Therefore, in large and medium diesel engine compressed air Starter has the primary valve.
3, compressed air brake system trouble analysis
(1) diesel engine not start
When the starting handle or push the handwheel to start position, if the diesel engine is not turning, the main reasons in the starting System. Possible reasons are the following aspects:
① Turning does not disengage, starting control of air in a closed state;
② air cylinder outlet valve or the main stop valve was not full;
③ insufficient starting air pressure;
④ starting air pipe dirt, lack of air flow;
⑤ starting air about valves in the system, such as the main starting valve, control valve, air Distributor, the cylinder valve
Card dead, damaged and leakage.
(2) the crankshaft rotation when starting but does not meet the required for the combustion speed
Possible causes and solutions are as follows:
① starting air pressure is too low and should be supplemented;
② diesel engine warm-cylinder insufficient lubricating oil viscosity is too large and should be warm-cylinder;
③ Start manipulating too quickly and should be starting afresh;
④ individual cylinder valve or air distributor bitten to death or the action is not flexible, you should check and removal of cleaning.
(3) a period of starting air pipe heating
Is usually caused by leakage of the valve from the cylinder. Starting valve leakage inspection and repair.
Second, diesel engine reversing device
Common fault analysis of commutation device:
Belonging to the reversing gear failures are:
① reversing valves of the bodies killed;
② commutation server failure: plug, oil spills, transfer Board, or bitten to death in extreme locations cannot reach the other extreme position;
③ Air distributor fault.
Belonging to the improper operation of:
① actions too quickly, camshaft is not yet in place is eager to start making your reversal fails;
② the reversing handle has in place, but because of the steady flow by the propeller on an original shift to high speed rotation, acute
On commutation failure as a Starter;
③ When the emergency brakes, too impatient, inappropriate timing of forces the brake, causing the steering to fail.
Third, speed Governor of diesel engine fault analysis
Engine speed changes when an exception occurs in the work, typically you should consider the following three factors: diesel
Performance deterioration of Governors of certain auxiliary equipment malfunction; Governor disorder in itself. Therefore, you should first check the following:
(1) confirm that the diesel engine load beyond the calibration of diesel engine load;
(2) check whether the load each cylinder serious inequality, whether normal combustion, fuel injector is in good working condition;
(3) check the Governor with fuel injection pump lever actuator is stuck between-delay and gap too large and loose;
(4) check the Governor load pointer to zero-zero digits are consistent with the injection pump;
(5) checks whether a Governors constituted body, control of air pressure is normal.
When you make these checks and after excluding, as Governor is still not working properly, the Governor's own fault, these failures usually are:
1, traveling or diesel engine speed oscillation
Traveling speed changes in rhythm, to manually stop Governor's role can be eliminated, but is let go after rhythmic speed changes. Speed oscillation means rhythm changes in speed and range is large, manually stop Governor eliminates fluctuations, fluctuations in speed does not immediately after letting go, but after the changes in speed or load fluctuations may occur, possible causes are:
(1) the Governor feedback system speed properly renewed stability should be adjusted;
(2) adjustable rod, high pressure pumps air or blockage;
(3) the Governor oil too dirty, bubbles or oil level is too low (see oil level oil level table);
(4) internal fault of Governors, flies and bearing wear, sliding valves stuck, compensation (damping) elasticity of spring invalidation;
(5) the Governor with diesel engines do not match.
2, speed of the output axis quiver (high-frequency vibrations)
Possible reasons are:
(1) the Governor-driven instability. Transmission gear worn loose, poor meshing, camshaft gear, engine shock absorber failure;
(2) flexible drive mechanism failure on the fly;
(3) the Governor does not have the install pedestal tighten evenly.
3, diesel engines are not up to full speed at full load
Possible reasons are:
(1) pull the fuel pump racks length is insufficient to trip the Governor output shaft or has reached the maximum output (scale of 10). This may be due to oil linkage block, air motion, Governor output shaft and injection pump oil supply caused by improper matches the scale factor;
(2) controlling air or scavenge air pressure too low or set speed is too low;
(3) the power piston is blocked;
(4) hydraulic system pressure too low or the oil plug.
4, when the diesel engine starting fuel pump wires can not be timely opened
Possible reasons are:
(1) the Governor oil pressure, such as gear pump wear, gear pump check valve leaks;
(2) starting speed is too low;
(3) boost server (at starting point using the rapid increase in the starting air Governor selection of lubricating oil pressure equipment in) poor actions;
(4) a certain oil bodies (such as stopping nuts) improper adjustments;
(5) speed settings or scavenge pressure fuel limiter (at the time of starting qualified by a sweep gas pressure Governor output shaft rotation of an assistive device) set value is too low.