Recently, a certain tone of the big V angry "BMW plastic oil pan" on the hot search, causing netizens to discuss, and then, the various bloggers on the topic again to create, with a wave of rhythm.
For example, some consumers buy second-hand BMWs and stage a plot of returning because the engine oil pan is a "plastic part" that is not resistant to collisions; there are video bloggers who believe that aluminum alloy products must have better performance than plastic products.
Let's not discuss whether the BMW oil pan is better made of plastic or the metal material is preferred, because the "plastic oil pan" is not exclusive to BMW, it is very common in the entire European car series.
From the current actual effect, the use of new plastic oil pan models, after using a certain year, many have different degrees of oil leakage phenomenon, is it caused by the material? Or is it pure coincidence?
Today, we first analyze from a rational point of view, help you solve the "oil leakage" problem, and secondly, we can find another big truth.
What the? Don't know what an oil pan is? Hurry up and get on the Royal Wind Express and find the answer!
What is an engine oil pan?
Oil pan (English name: Oil Pan), located at the very bottom of the engine, the role is to close the crankcase as the shell of the oil storage tank, collect and store the oil flowing back by the friction surfaces of the fuel engine, and conduct part of the heat to prevent the oil from oxidation.
Because the oil pan is exposed to the bottom of the car, the environment is relatively harsh, and the oil pan is usually stamped from thin steel plates. In recent years, with the application of new materials, oil pans made of new plastic materials such as ethane, nylon, and phenolic resin have appeared at the bottom of the engine.
▲ The red dashed area is the engine oil pan
Big V must be right?
After having a basic understanding of the oil pan, the curious babies in front of the screen must want to drill into the bottom of the BMW to see if it is plastic or not.
In fact, the big V alludes to the N20 series of engines (BMW four-cylinder engine representative), it does use a new plastic oil pan design, and it is widely used in BMW's models.
In addition, the N20 series engine was discontinued for many years, replaced by a new B48 series engine, whose oil pan was made of magnesium aluminum alloy.
Therefore, the expression of "BMW has been completely replaced by a plastic oil pan in recent years" is not rigorous, and even has the suspicion of misleading fans.
New plastics are not "fresh"
Engine oil pan has always been made of steel or aluminum because of the heat transfer, sealing, stability, oil fluidity and standard impact mechanics of the metal material.
In fact, "new plastic oil pan" is not a new term, it has been in service with modern BBA models and Land Rover models for many years. Perhaps, the word "plastic" itself gives the impression of "low-end, flooded", but is it really as powerful as its name?
Plastic has a saying: good evil I also call "polymer" good logging?
▲ The left is the new plastic oil pan, and the right is the aluminum alloy oil pan
Plastic is good, but it also has hard wounds
In fact, automobile manufacturing belongs to the process of overall system optimization, and engineers have been working hard to reduce the production cost of parts through material and structural optimization.
A simple example: the traditional steel plate stamping parts and aluminum alloy die casting parts are completed by each individual or independent part, while the new plastic oil pan not only has low mold manufacturing costs, but also eliminates the mechanical processing processes such as shaping and cutting edges after the stamping of the steel plate, which improves the yield.
In addition, the new plastic oil pan adopts an integrated design, which eliminates or reduces the number of individually manufactured spare parts, thereby reducing the production cost of oil pan.
According to a large number of statistics, the production cost of new plastics and traditional materials under the condition of similar strength and stiffness is 30%-40% lower than that of die-cast aluminum alloy oil pan; in terms of lightweight, nylon plastic injection molded parts are 50% lighter than single-layer steel plate stamping parts, and 30%-40% lighter than aluminum alloy die castings.
Conclusion: In terms of material properties, the "new plastic oil pan" is better than the "aluminum alloy oil pan", and the application prospect is bright. However, the premise must solve a "hard wound", that is, its material structure rigidity needs to be strengthened.
The truth about the N20 engine oil spill?
The oil pan of bmw N20 series engines is made of phenolic resin (commonly known as plastic bakelite), and the shell is designed with reinforced ribs to improve structural rigidity.
However, phenolic resins with excellent heat resistance, ablation resistance and electrical insulation properties also have defects such as large brittleness and high shrinkage.
The engine runs at high temperature and high pressure all year round, in addition to the oil pan rubber pad is easy to age, the phenolic resin oil pan with poor aging resistance will also deform that is difficult to detect with the naked eye, resulting in oil leakage.
It is worth noting that the N20 engine also has an "alternative" oil pan, which is mainly found on xDrive models, and in order to improve the strength of the front axle differential in the four-wheel drive system, its oil pan (pictured below) is made of magnesium aluminum alloy material.
From the side, the new plastic oil pan led by "plastic bakelite" seems to have a long way to go.
Which "babies" need to be paid attention to?
How do I know if my foal has an N20 engine? Some of the models are listed below:
BMW 2 Series Convertible (F23) '2015–17
BMW 3 Series (F30-F80) '2012–21
BMW 4 Series (F32/33/36) '2013–20
BMW 5 Series (F07/F10/F11/F18) ' 2009–2017
BMW X1 xDrive28i (E84) '2011–12
BMW X4 xDrive28i M Performance Accessories (F26) '2014–18
BMW X5 (F15) '2013–18
BMW Z4 (E89) ' 2009–16
How to solve the oil pan oil leakage?
From the year of the above model, it is known that the N20 engine is basically a product before 2018. According to the feedback of bmw owners and auto parts factories, the oil spill phenomenon of the oil pan of the N20 series engines mostly appears on BMW models with a total mileage of nearly 100,000 kilometers of five years or more. The general solution is to replace the deformed oil pan with the rubber pad that is aging at high temperature.
Basically, the models equipped with N20 engines have passed the warranty period, and after the insurance is released, the owner needs to spend nearly 10,000 yuan to go to the 4S shop for repair and replacement, but the probability of this "high consumption" is actually very low.
▲ 4S shop quotation reference: material fee 4,500 yuan + working hours fee 5,000 yuan
Because the number of models equipped with the N20 series engine is very large, the automotive aftermarket has developed a special aluminum alloy oil pan for this engine, which is much cheaper. Counting the material cost and man-hour cost, it only costs about 1,000 yuan to solve the troubles caused by the oil spill of the phenolic resin oil pan.
▲ Market quotation reference: material fee 450 yuan / working hours cost 500 yuan
Aluminum alloy oil pan to do sound insulation?
It should be noted that the noise reduction and shock resistance of the metal oil pan is weaker than that of the new plastic oil pan, which will lead to the performance of the car engine NVH. Test results show that the noise generated by automobile engines using lightweight new material oil pans is reduced by 1dB (decibel) when operating.
In addition, it is not difficult to find from the aluminum alloy oil pan used in the new B48 series that the engineers added acoustic cotton to the bottom of the engine in order to reduce the noise of engine operation.
Therefore, if you have an aluminum alloy oil pan in the upgraded market, you may also wish to put the matter of oil pan sound insulation and vibration filtering on the agenda.
epilogue
Does the new technology need to be perfect enough to be put into mass production? The answer is no.
For example, the volkswagen double-clutch transmission in the early years is not perfect, after being put into the domestic market in 2009, the official gave a 10-year/ 160,000-kilometer warranty, behind these two sets of figures, Volkswagen constantly upgraded and improved the unstable characteristics of the dual-clutch.
Another example is the Toyota Prius, which also achieved today's Atskinson cycle engine after market sales and real-time user data feedback. Look at the "semi-finished products" produced by a number of new automotive brands today.
In the same way, the BMW N20 engine uses a new plastic oil pan, which is also to test the stability of the vehicle, engine durability, ease of maintenance and so on. Although the new plastic oil pan did not perform well on the N20, BMW made up for it and used a more mature and reliable aluminum oil pan on the new B48 engine.
We have reason to believe that with the large number of new materials put into use, and through increasing improvement and popularization, in a few years, the competitiveness of new plastic oil pans may appear in front of us in a new posture.
Looking back at the entire "BMW oil pan incident", the whole network is eating melon to see the hilarity, until we understand the truth behind the incident. Finally, let's take another bite of melon: Who do you think is the biggest beneficiary of this incident? Welcome to leave a message and interact with me.
Text / Harvest Brother
Photography / Web
Typography / Harvest Brother
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