一些小型混凝土攪拌車司機(jī)反映，跟朋友同時(shí)購買的同一款攪拌車，自己的車輛在使用一段時(shí)間后發(fā)動(dòng)機(jī)就會(huì)出現(xiàn)問題，可是朋友的車輛發(fā)動(dòng)機(jī)卻沒事，這到底是怎么一回事呢？一起來了解一下吧。

Some small concrete mixer drivers reported that the same mixer they bought at the same time with their friends will have engine problems after using their vehicles for a period of time, but their friends' vehicle engines are all right. What's the matter? Let's have a look.

1. 攪拌車的維修數(shù)據(jù)應(yīng)用不當(dāng)

1. Improper application of maintenance data of mixer truck

在攪拌車維修中不能科學(xué)的選擇維修數(shù)據(jù)是造成機(jī)件早期損壞的重要原因。比如氣門與氣門座接觸面的寬度，規(guī)定進(jìn)氣門為1-2.2mm，排氣門為1.5-2.5mm。

The failure to scientifically select maintenance data in the maintenance of mixer truck is an important reason for the early damage of mechanical parts. For example, the width of the contact surface between the valve and the valve seat is specified as 1-2.2mm for the inlet valve and 1.5-2.5mm for the exhaust valve.

但在實(shí)際維修當(dāng)中，很多人認(rèn)為寬一點(diǎn)比窄一點(diǎn)要好，習(xí)慣選用上限或接近上限值，因?yàn)閯傂藓玫能嚉忾T工作面寬度就已經(jīng)接近使用極限了。再比如氣門腳間隙，一般車輛規(guī)定為0.2-0.25mm，但在維護(hù)調(diào)整中也會(huì)認(rèn)為間隙大一點(diǎn)比小一點(diǎn)好，因此，超上限使用，實(shí)際上間隙過大，不但降低發(fā)動(dòng)機(jī)功率，還會(huì)出現(xiàn)敲擊聲而早期損壞。

However, in actual maintenance, many people think that it is better to be a little wider than a little narrower, and they are used to choosing the upper limit or close to the upper limit, because the width of the valve working surface just repaired is close to the limit of use. Another example is the valve foot clearance, which is generally specified as 0.2-0.25mm for vehicles, but it is also considered that a larger clearance is better than a smaller clearance in maintenance and adjustment. Therefore, if it is used beyond the upper limit, in fact, the clearance is too large, which will not only reduce the engine power, but also cause knocking and early damage.

2. 氣門的光磨

2. Smooth grinding of valve

在攪拌車的維修中，如果氣門出現(xiàn)燒蝕、麻點(diǎn)及凹陷時(shí)，均應(yīng)進(jìn)行光磨，一般是在光磨機(jī)上進(jìn)行，作業(yè)時(shí)需要注意四個(gè)問題：一是保證氣門頭與桿部同心，否則應(yīng)先校直；二是光磨輛在能磨出完整的錐面的前提下是越小越好；三是盡量提高表面光潔度；四是氣門桿端部凹陷應(yīng)予以磨平。

In the maintenance of mixer truck, if the valve appears ablation, pitting and depression, it should be polished, usually on the grinder. Four problems should be paid attention to during operation: first, ensure that the valve head is concentric with the rod, otherwise it should be straightened first; Second, on the premise that the smooth grinding vehicle can grind a complete cone, the smaller the better; Third, try to improve the surface finish; Fourth, the depression at the end of the valve stem should be ground flat.

3. 氣門導(dǎo)管的鉸銷

3. Hinge pin of valve guide

氣門桿與氣門導(dǎo)管配合間隙是決定氣門導(dǎo)管使用壽命的關(guān)鍵，因此當(dāng)更換新的氣門導(dǎo)管時(shí)，鉸銷時(shí)應(yīng)嚴(yán)格掌握好配合間隙，使用各攪拌車車型規(guī)定間隙的下限，可有效延長使用壽命。

The fit clearance between the valve stem and the valve guide is the key to determine the service life of the valve guide. Therefore, when replacing the new valve guide, the fit clearance should be strictly controlled when hinge pin is used. The lower limit of the clearance specified by each mixer model can effectively prolong the service life.

4. 氣門的研磨

4. Grinding of valve

氣門的研磨分為兩種情況：一是氣門與氣門座只有輕微麻點(diǎn)，不需要光磨和鉸銷時(shí)的研磨；二是氣門與氣門座均經(jīng)過光磨和鉸銷后的研磨。前者先用足金鋼砂研磨，將麻點(diǎn)研磨掉后，再用細(xì)金剛砂研磨，后涂上機(jī)油研磨，直至密封符合要求，寬度符合規(guī)定為止。后者只有密封性達(dá)不到要求時(shí)才進(jìn)行研磨，但操作時(shí)一定要注意，不要過分用力，嚴(yán)禁將氣門上下敲打，否則將出現(xiàn)凹形砂痕，影響維修質(zhì)量。

The grinding of valves can be divided into two cases: first, there are only slight pits between valves and valve seats, and there is no need for light grinding and grinding when pinning; Second, the valve and valve seat are polished and ground after hinge pin. The former is first ground with full gold steel sand, then the pitting is removed, then ground with fine emery, and then coated with engine oil until the sealing meets the requirements and the width meets the regulations. The latter can only be grinded when the sealing performance fails to meet the requirements, but it must be noted during operation that excessive force is not allowed, and it is strictly forbidden to knock the valve up and down, otherwise concave sand marks will appear, affecting the maintenance quality.

攪拌車發(fā)動(dòng)機(jī)出故障不可怕，可怕的是維修不正確，那發(fā)動(dòng)機(jī)的性能只會(huì)越來越差，所以存在的問題就要及時(shí)進(jìn)行處理，更多內(nèi)容就來網(wǎng)站http://www.mothernature2u.com咨詢吧。

It's not terrible that the mixer truck engine breaks down. The terrible thing is that the maintenance is not correct, and the performance of the engine will only get worse and worse. Therefore, the existing problems should be dealt with in time, and more content can be found on the website http://www.mothernature2u.com Consult.