Butter is a grease commonly used in repair of construction machinery. It can play a role of lubrication and sealing. However, improper use will cause some parts of the aerial vehicle adverse effects, let's see what parts of the aerial vehicle can not be painted butter bar.

 

　　一、高空作業車輪胎螺母涂黃油

 

　　1. Overhead truck tires, nuts and butter.

 

　　為了容易擰緊螺母和防止銹蝕，不少修理工在輪胎的螺栓螺母上涂油。實際上這是一種錯誤做法。因為輪胎螺母擰緊后，螺紋間就具有自鎖的特征。這是由于螺紋螺旋角小于螺紋間的當量摩擦角的緣故。給定的螺栓聯接中，螺旋升角是一定值，而當量摩擦角則隨螺紋間的摩擦狀態而變。顯然，涂油后螺紋間的當量摩擦角減小，螺栓聯接的自鎖性能變差。因此在輪胎的螺栓和螺母上對不要涂潤滑脂或滴上潤滑油。這樣做，反而會使螺母松動，甚至釀成事故。

 

　　In order to easily tighten the nuts and prevent rust, many repairmen grease the bolts and nuts of the tires. In fact, this is a wrong way. Because the tyre nut is tightened, the screw thread has the characteristics of self locking. This is due to the fact that the screw angle of thread is smaller than the equivalent friction angle between threads. In a given bolted connection, the helix angle is a certain value, and the equivalent friction angle varies with the friction state between threads. Obviously, the equivalent friction angle between the threads after oil painting is reduced, and the self-locking performance of the bolt connection becomes worse. Therefore, no grease or grease should be applied to the bolts and nuts of the tire. In doing so, the nut will become loose and even cause an accident.

 

　　二、汽缸墊上涂黃油

 

　　Two. Grease the cylinder mats.

 

　　因此，有些修理工在安裝汽缸墊時，就會在高空作業車汽缸墊上涂上一層黃油，認為這樣可以增加柴油機的密封性。殊不知，這樣做反而影響了柴油機的工作性能。汽缸墊是柴油機缸體與缸蓋之間比較重要的密封件，它不但能密封汽缸內所產生的高溫高壓氣體，而且還能密封汽缸蓋和缸體內的冷卻水和潤滑油，所以在拆裝汽缸墊時，都要特別注意它的密封質量。如果安裝時在汽缸墊上涂黃油，當汽缸蓋螺栓擰緊時，一部分黃油就會被擠壓到汽缸水道和油道中，留在缸墊間的黃油在汽缸工作時，由于受高溫影響，一部分會流人汽缸燃燒，另一部分則殘留在缸體與缸蓋的結合面上，使缸墊、缸蓋與機體平面之間產生縫隙，高溫高壓燃氣很容易從此處沖擊汽缸墊，毀壞缸墊，成漏氣。此外，黃油長時間處在高溫狀態下還會產生積炭，造成缸墊過早老化變質。因此安裝汽缸墊時切勿涂抹黃油。

 

　　Therefore, when some repairmen install the cylinder gasket, they will put a layer of butter on the cylinder gasket of the aerial vehicle, thinking that this can increase the seal of the diesel engine. Little does it know that doing so affects the performance of the diesel engine. Cylinder gasket is the most important seal between cylinder block and cylinder head of diesel engine. It not only can seal the high temperature and high pressure gas produced in cylinder, but also can seal the cooling water and lubricating oil in cylinder head and cylinder block. Therefore, when disassembling and assembling cylinder gasket, special attention should be paid to its sealing quality. If butter is applied to the cylinder pad during installation, when the cylinder head bolt is tightened, part of the butter will be extruded into the cylinder water channel and oil channel. When the butter remaining in the cylinder pad is working, due to high temperature, part of the butter will flow to the cylinder to burn, the other part will remain on the cylinder head and the cylinder joint surface, so that the cylinder can be made. There is a gap between the gasket, cylinder head and the plane of the engine block. High temperature and high pressure gas can easily impact the gasket from here, destroy the gasket and leak. In addition, butter will generate carbon deposition at high temperature for a long time, resulting in premature aging and deterioration of cylinder mats. Therefore, do not apply butter when installing cylinder gaskets.

 

　　以上兩種問題，對于某些高空作業維修人員來說可能是不經意間犯的小錯誤，但是如果日積月累就可能出現大的問題，希望大家能夠引以為戒。

 

　　The above two problems, for some altitude maintenance personnel may be inadvertently made a small mistake, but if accumulated may be a major problem, I hope you can take warning.