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The results of the recent investigation into the Mercedes oil leakage issue have finally been released. It turned out that during the engine’s assembly process, the bolts used to secure the oil splash guard were left inside the engine. As the engine ran at high speed, the big end of the connecting rod in the second cylinder struck one of these remaining bolts, causing the bolt to break through the cylinder wall and resulting in the oil leakage. “This time the bolt fell inside the engine, but what if it fell into other oil-containing parts of the car? ” What other components in a car contain oil? ①Engine oil serves to lubricate, cool, seal, clean, and prevent rust. Engine oil is regarded as the \"blood\" of a car; it lubricates the engine and removes impurities during its circulation, before being sent to the oil filter for purification. Engine oil has strong heat resistance and can absorb heat from the engine to assist in heat dissipation. ②Transmission fluid: Transmission fluid serves to lubricate, cool, clean, prevent rust, and transmit power. The movements and structures within a transmission are much more complex than those in an engine, and transmission fluid is of utmost importance. Especially automatic transmission fluid, which not only lubricates and cools the gearbox gears but also has the responsibility of transmitting power. ③Brake fluid: Brake fluid serves to lubricate and transmit braking pressure. A car’s brake fluid, also known as automotive braking fluid, is the liquid used in a vehicle’s hydraulic braking system. When the brakes are applied, the force applied from the pedal is transmitted by the pistons in the master brake cylinder, through the brake fluid, to the individual brake calipers attached to the wheels. This causes the friction pads to expand, thereby stopping the vehicle from moving forward. The brake fluid plays a role in transmitting force throughout this process. ④Power steering fluid: Power steering fluid serves to lubricate and transmit the power for steering. Power steering fluid is a special type of fluid used in a vehicle’s power steering system; through hydraulic action, it enables the steering wheel to be very easy to handle and control. ⑤Shock absorber fluid is used in shock absorbers to reduce the up-and-down vibrations of a vehicle. These oils are crucial for cars; oil leaks can directly affect the car’s performance, leading to poor lubrication of components and insufficient cooling, which in turn can cause premature damage to those components and even result in serious safety accidents. Besides the reasons mentioned in the news, what other causes can lead to oil leaks? In fact, cars can experience oil leaks whether they are new or old; many major problems often start with oil leaks. Common causes of oil leakage: ① Poor product quality, materials, or manufacturing processes, as well as issues with the structural design ； ②Improper assembly, unclean mating surfaces, damaged or displaced gaskets, or installation not carried out in accordance with the operating specifications ； ③Failure to function can be caused by uneven tightening torque of the nuts, stripped threads, broken fasteners, or loose connections ； ④After long-term use, the sealing material suffers excessive wear, ages and deteriorates, and becomes deformed or ineffective ； ⑤Excessive lubricant added, oil level too high, or wrong type of oil used ； ⑥Warpage of the joint surfaces of the components and damage to the housing cause lubricant to leak out ； ⑦When the ventilation plug or check valve becomes clogged, the pressure difference between the inside and outside of the housing often causes oil leakage at the weak sealing points. The structure of a car is extremely complex; it is made up of thousands of components, and the interaction, movement, and functioning of each set of these components require the aid of oil in order to function properly. The application of oil in the production process of smart factories: As an important measurement parameter in the automated manufacturing processes of factories, the measurement of pressure relies on oil; it is through the transmission via diaphragms and isolating oil that pressure is applied to the sensing elements. The isolation oil serves to transmit pressure and protect the sensing elements. The figure below shows the sensor structure of a piezoresistive pressure transmitter. When process pressure acts on the diaphragm, it is transmitted to the piezoresistor through isolation oil; different pressures result in different resistance values, which are then converted into an electrical current signal using a Wheatstone bridge, thereby enabling pressure measurement. http://yunrun.com.cn/upload/201906/07/201906070213575416.png The structure of sensors that contain oil also presents certain risks. In the industrial sector, this risk may not be related to bolts, but if problems arise, the losses can be far more than 1 million. When facing extremely complex pressure measurement conditions, such as high vacuum or high corrosion levels, the diaphragm can easily get damaged, leading to leaks of the isolation oil. This oil then enters the process pipelines, causing contamination of the medium, and such contamination is irreversible; it results in significant waste of materials and cost losses. For example, the culture medium used in biopharmaceutical fermentation tanks is extremely expensive; should the isolation oil leak, it can cause the medium to be ruined and rendered unusable, resulting in property losses of millions. In more severe cases, the isolation oil may react chemically with the medium, producing toxic substances or even leading to explosions that cause additional harm to people. However, this isolation oil is a very crucial element for pressure measurement, and such leakage risks are difficult to avoid in pressure measurements. A group of engineers came up with a solution: just use no oil, right? Thus, they designed the diagram shown below: http://yunrun.com.cn/upload/201906/07/201906070214491839.png. The diagram above depicts the sensor structure of a ceramic diaphragm pressure transmitter; it uses a capacitive measurement principle. The difference lies in the fact that the process pressure acts directly on the ceramic diaphragm, thereby changing the distance d between the plates, and as a result the capacitance value between those plates also changes. The pressure value is thus converted into a capacitance value. The most remarkable thing is that the medium between the two electrodes is air, and there isn’t a single drop of oil inside the entire sensor; thus, the risk of oil leakage caused by damage to the diaphragm is completely eliminated from a fundamental perspective. In addition to the feature of being oil-free, these clever engineers have also developed a core technology for ceramic diaphragms: they use Al2O3 with a purity of 99.9%, which makes it particularly suitable for use in conditions of high vacuum, high corrosion, high wear, and frequent pressure fluctuations. Furthermore, once the ceramic diaphragm breaks, the sensor will detect it and issue an alarm, thereby further enhancing the safety of the ceramic diaphragm. http://yunrun.com.cn/upload/201906/07/201906070218204250.png Source: Changhui Instruments http://yunrun.com.cn/