Reasons why the mixer engine ages prematurely 1. Improper application of mixer truck maintenance data: Maintenance can not scientifically select maintenance data is an important cause of early damage to the machine. For example, the width of the contact surface between the valve and the valve seat defines the intake valve as 1 to 2.2 mm and the exhaust valve as 1.5 to 2.5 mm. However, in the maintenance, people often think that the width is narrower than the narrower one, and the habitual upper limit or near upper limit value is used. Therefore, the width of the just-repaired car valve face has already approached the limit of use. Another example is the valve clearance, which is generally set at 0.2 to 0.25 mm. However, in the maintenance adjustment, it is also considered that the gap is larger than the smaller one. Therefore, the upper limit is used. In fact, the gap is too large, not only reduces the engine power, but also the knocking sound (gas from the door) and early damage. Cement Mixer, Cement Mixer Price, Concrete Mixer, Concrete Mixer Price 2. The poor maintenance quality of the mixer truck The outstanding problem in the maintenance operation is that the machining quality of the valve face and valve seat working face cannot meet the requirements, resulting in ablation, depression and early damage of the working face; the camshaft bearing has the clearance and contact in scraping. Area, the concentricity of the bearings can not meet the requirements, accelerate wear, abnormal sound caused early damage; valve guide tube replacement of new parts, the reaming quality can not meet the requirements, directly affect the valve and valve seat life. 4. Shave of the camshaft bearing: The scraping of the camshaft bearing belongs to the manual operation to ensure the quality is difficult. For scraping convenience, and usually in the cylinder body processing, so we should pay special attention to four issues: First, to determine the diameter of the inner hole after the bearing scraping (formula expressed as: inner diameter = journal diameter measured value + under clearance Limit value + measured value of bearing and seat hole interference); Second, try to pay attention to maintaining the coaxiality of the bearing bore and the outer circle in the scraping; Thirdly, try to match the edge scraping and the journal (the clearance at this time is the interference Volume + fit gap), and to ensure uniform distribution of contact marks; Fourth, when the bearing is pressed into the seat hole, it should pay attention to the positive oil hole. After scraping, the camshaft is loaded into the camshaft and rotated several times. If appropriate, the contact surface area should reach 75% or more and be evenly distributed. The clearance is in compliance with the regulations. Cement Mixer, Cement Mixer Price, Concrete Mixer, Concrete Mixer Price 5. Adjustment of valve foot clearance: In the normal use of all parts of the air distribution mechanism, the valve foot clearance will change with the wear of the parts. If the cam, the valve rod end surface and the contact surface of the tappet wear, the gap will become larger, and the gap between the valve head and the valve seat wears, the gap will become smaller. Therefore, the middle value of the clearance should be taken during the adjustment. If 0.2 ~ 0.25mm is specified, 0.22mm can be taken. This not only takes care of the actual situation of the gap change, but also considers the measurement error problem, which can fully guarantee the realization of the valve foot clearance. 6. Valve polishing: In the maintenance operation, if the valve is ablated, pitted and pitted, light grinding should be carried out (in case of serious change of valve). Usually in the valve light mill, work should pay attention to four issues: First, to ensure that the valve head and the rod concentric, otherwise it should be straightened; Second, the amount of light grinding in the premise of grinding a complete cone can be smaller The third is to increase surface finish as much as possible; fourth is to recess the end of the valve stem. Cement Mixer, Cement Mixer Price, Concrete Mixer, Concrete Mixer Price 7. Valve seat reaming: The valve seat reaming is usually manual operation, and three issues should be paid special attention: First, the smaller the reaming amount is, the better the reaming amount is; Second, when the reaming force should be uniform, the knife must be lighter and less hinged to observe, so as to ensure less reaming quantity and higher finish. The third is to match the valve and determine the position and width of the working surface. The position should be adjusted to the middle and lower parts of the valve cone, and the upper and lower reamers can be used to adjust the upper or lower position. The width of the working surface, the intake valve can be controlled at 0.9mm (prescribed as 1 ~ 2.2mm), the exhaust valve can be mastered at 1.4mm (defined as 1.5 ~ 2.5mm). Practice has proved that the width above the valve and valve seat after grinding, intake valve up to 1mm, exhaust valve up to 1.5mm, are in the lower limit of the specified width, can greatly increase its service life. Cement Mixer, Cement Mixer Price, Concrete Mixer, Concrete Mixer Price 8. Valve grinding: Valve grinding is divided into two cases. First, the valve and seat are only slightly pockmarked and do not require grinding during light grinding and reaming. Second, the valve and seat have been polished and reamed. Grinding. The former is first sanded with a rent, and the pits are ground off, then ground with fine corundum, and finally coated with oil until the seal meets the requirements and the width is in compliance. The latter only performs the grinding when the sealing performance is not up to the requirements, but the operation must be careful not to use excessive force. It is forbidden to knock the valve up and down, or there will be concave sand marks, which will affect the maintenance quality. Cement Mixer, Cement Mixer Price, Concrete Mixer, Concrete Mixer Price Mitsubishi Android Car Dvd
1.Mitsubishi Android Car Dvd,this series have many models,can fit different car of Mitsubishi.Mitsubishi Android Car Dvd(multimedia Car Dvd),This car dvd gps for is high
quality,we provide 12 months warranty, the cpu is Octa core Rockchip
PX5 Cortex A9,it is more powerful and more stable.
2.Mitsubishi Android Car Dvd,Support easy-connected feature: Compatible
with android smartphones and devices, the easy-connected feature enables mutual
control between your smartphone and car head uni. You can simply connect and
synchronize your smartphone to the uni via USB, with no additional software
required.
3.Mitsubishi Android Car Dvd fits for Outlander 2015/Outlander 2014/Outlander 2006-2012/Lancer 2014-2015/Lancer 2006-2012/ASX 2010-2012/PAJERO 2006-2012 -seven models now ,we also will develop on more models.
Mitsubishi Android Car Dvd,Mitsubishi Android 4.2 Car Dvd,Mitsubishi Android 5.1 Car Dvd,Mitsubishi Android Car Dvd SHEN ZHEN KLYDE ELECTRONICS CO., LTD ,
The engine distribution system of the mixer truck has many manual operations during maintenance. Due to technical differences and awareness of the maintenance personnel, the maintenance quality is difficult to meet the specified requirements; therefore, the maintenance quality of the valve distribution mechanism should be emphasized in the maintenance. Take effective measures to improve the quality of maintenance to extend its service life.
3. Valve guide reaming: Valve stem and valve guide with the clearance is the key to determine the valve guide life, so when replacing a new valve guide, reaming should be strictly controlled with the clearance, the use of each vehicle models specified clearance gap The lower limit can effectively extend the service life. Cement Mixer, Cement Mixer Price, Concrete Mixer, Concrete Mixer Price