一些小型混凝土攪拌車(chē)司機反映，跟朋友同時(shí)購買(mǎi)的同一款攪拌車(chē)，自己的車(chē)輛在使用一段時(shí)間后發(fā)動(dòng)機就會(huì )出現問(wèn)題，可是朋友的車(chē)輛發(fā)動(dòng)機卻沒(méi)事，這到底是怎么一回事呢？一起來(lái)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(chē)的維修數據應用不當

1. Improper application of maintenance data of mixer truck

在攪拌車(chē)維修中不能科學(xué)的選擇維修數據是造成機件早期損壞的重要原因。比如氣門(mén)與氣門(mén)座接觸面的寬度，規定進(jìn)氣門(mén)為1-2.2mm，排氣門(mén)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)際維修當中，很多人認為寬一點(diǎn)比窄一點(diǎn)要好，習慣選用上限或接近上限值，因為剛修好的車(chē)氣門(mén)工作面寬度就已經(jīng)接近使用極限了。再比如氣門(mén)腳間隙，一般車(chē)輛規定為0.2-0.25mm，但在維護調整中也會(huì )認為間隙大一點(diǎn)比小一點(diǎn)好，因此，超上限使用，實(shí)際上間隙過(guò)大，不但降低發(fā)動(dòng)機功率，還會(huì )出現敲擊聲而早期損壞。

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(mén)的光磨

2. Smooth grinding of valve

在攪拌車(chē)的維修中，如果氣門(mén)出現燒蝕、麻點(diǎn)及凹陷時(shí)，均應進(jìn)行光磨，一般是在光磨機上進(jìn)行，作業(yè)時(shí)需要注意四個(gè)問(wèn)題：一是保證氣門(mén)頭與桿部同心，否則應先校直；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(mén)桿端部凹陷應予以磨平。

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(mén)導管的鉸銷(xiāo)

3. Hinge pin of valve guide

氣門(mén)桿與氣門(mén)導管配合間隙是決定氣門(mén)導管使用壽命的關(guān)鍵，因此當更換新的氣門(mén)導管時(shí)，鉸銷(xiāo)時(shí)應嚴格掌握好配合間隙，使用各攪拌車(chē)車(chē)型規定間隙的下限，可有效延長(cháng)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(mén)的研磨

4. Grinding of valve

氣門(mén)的研磨分為兩種情況：一是氣門(mén)與氣門(mén)座只有輕微麻點(diǎn)，不需要光磨和鉸銷(xiāo)時(shí)的研磨；二是氣門(mén)與氣門(mén)座均經(jīng)過(guò)光磨和鉸銷(xiāo)后的研磨。前者先用足金鋼砂研磨，將麻點(diǎn)研磨掉后，再用細金剛砂研磨，后涂上機油研磨，直密封符合要求，寬度符合規定為止。后者只有密封性達不到要求時(shí)才進(jìn)行研磨，但操作時(shí)一定要注意，不要過(guò)分用力，嚴禁將氣門(mén)上下敲打，否則將出現凹形砂痕，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(chē)發(fā)動(dòng)機出故障不可怕，可怕的是維修不正確，那發(fā)動(dòng)機的性能只會(huì )越來(lái)越差，所以存在的問(wèn)題就要及時(shí)進(jìn)行處理，更多內容就來(lái)網(wǎng)站http://www.jqeq.cn咨詢(xún)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.jqeq.cn Consult.