Automatic feeding mixer after a long time of use, there will be some situations, these situations have big and small, small problems will not have a big impact, but big situation may damage the automatic feeding mixer, today I will introduce the cause of engine damage.

1、气门脚空地的调整：配气安排各机件在正常运用中，跟着零件的磨损，气门脚空地将发生改动。如凸轮、气门杆端面及挺杆接触面磨损后空地将变大，而气门头与气门座磨损后空地又变小，因此，在调整中应取空地的基地值为宜。如规矩为0.2~0.25mm,可实取0.22mm,这么既照顾了空地改动的实际情况，又思考了测量误差疑问，可充沛保证气门脚空地效果的完成。

1. Adjustment of valve foot clearance: valve arrangement in normal operation, with the wear of parts, valve foot clearance will be changed. If the cam, valve stem end face and tappet contact surface are worn, the open space will become larger, and the open space will become smaller after the valve head and valve seat are worn. Therefore, the base value of the open space should be taken in the adjustment. If the rule is 0.2 ~ 0.25 mm, the actual value can be 0.22 mm, which not only takes care of the actual situation of the air space change, but also considers the measurement error question, which can fully ensure the completion of the air space effect of the valve foot.

2、气门座的铰削：气门座铰削通常为手作业业，应格外重视三个疑问：一是在凹陷、斑驳，能铰出无缺锥面的基础上，铰削量越小越好；二是铰削时用力要均匀，起刀收刀要轻，少铰多调查，以保证较少的铰削量和较高的光洁度;三是与气门试配，判定好作业面方位和宽度。

2. Valve seat reaming: valve seat reaming is usually manual operation, so we should pay special attention to three questions: first, on the basis of eliminating depression and mottling and being able to ream out the intact cone surface, the smaller the reaming amount is, the better; second, the force should be uniform when reaming, and the cutter should be light when starting and closing, and more investigation should be carried out with less reaming to ensure less reaming amount and higher finish; Third, try to match with the valve to determine the orientation and width of the working face.

方位应调整到气门锥面的中下部，偏上或偏下可用上、下口铰刀进行调整。作业面宽度，进气门可掌握在0.9mm(规矩为1~2.2mm)，排气门可掌握在1.4mm(规矩为1.5~2.5mm)。实践证明上述宽度在气门与气门座研磨后，进气门可达1mm,排气门可达1.5mm,均在规矩宽度的下限，能大大提高其运用寿数。

The position should be adjusted to the middle and lower part of the valve cone. The upper and lower reamers can be used to adjust the position. The width of working face can be controlled within 0.9mm (1 ~ 2.2mm) for intake valve and 1.4mm (1.5 ~ 2.5mm) for exhaust valve. Practice has proved that the width of the intake valve and the exhaust valve can reach 1 mm and 1.5 mm after grinding the valve and valve seat, which are all in the lower limit of the regular width and can greatly improve the service life.

3、搅拌车修补质量差在修补作业中出色的疑问是气门与气门座作业面加工质量达不到恳求，构成作业面烧蚀、凹陷而前期损坏；凸轮轴轴承在刮削中其协作空地、接触面积、各轴承同心度达不到恳求，加速磨损，呈现异响构成前期损坏；气门导管在更换新件时，铰削质量达不到规矩恳求，直接影响气门及气门座运用寿数。

3. The problems of poor repair quality of mixer truck in repair operation are that the machining quality of valve and valve seat working surface can not meet the requirements, which results in ablation and depression of working surface and early damage; the clearance, contact area and concentricity of camshaft bearing can not meet the requirements in scraping, which accelerates wear and presents abnormal sound, which results in early damage; when the valve guide is replaced with new parts, the hinge is broken The cutting quality can not reach the standard, which directly affects the service life of valve and valve seat.

自动上料搅拌车

Automatic feeding mixer

4、凸轮轴轴承的刮削：凸轮轴轴承的刮削归于手作业业，保证质量有一定难度。为刮削便利，又通常在气缸体外加工，因此应格外留意四个疑问：一是要判定好轴承刮削后内孔的直径;二是刮削中要尽量留意坚持轴承内孔与外圆的同轴度;三是边刮削边与轴颈试配，并保证接触印痕分布均匀;四是将轴承压入座孔时，应留意对正油孔。刮削后装入凸轮轴，翻滚数圈，视情进行恰当修整，接触面积应抵达75%以上并分布均匀，空地符合规矩。

4. Scraping of camshaft bearing: scraping of camshaft bearing belongs to manual operation, so it is difficult to ensure the quality. For the convenience of scraping, it is usually processed outside the cylinder body, so we should pay special attention to four questions: first, we should determine the diameter of the bearing inner hole after scraping; second, we should pay attention to the coaxiality of the bearing inner hole and the outer circle during scraping; third, we should try to match with the journal while scraping, and ensure that the contact marks are evenly distributed; fourth, we should pay attention to aligning the oil hole when pressing the bearing into the seat hole. After scraping, install the camshaft, roll for several circles, and properly trim according to the situation. The contact area should reach more than 75% and be evenly distributed, and the open space should conform to the rules.