Hello everyone, I'm Sir Lee. On the one hand, I would like to say hello to everyone and tell you that Sir Lee is back and presents the first issue of my work after my return. On the other hand, I intend to start with the article introducing the 4D20 diesel engine in this issue, and gradually introduce the diesel engines at home and abroad, each displacement, and each application, if you are interested, please pay attention to ~
Speaking of a large number of domestic cylinder diesel engine products, its minimum displacement is about 2L, if you want to choose a classic product for the beginning of the "Li Xie diesel engine" series, as a Haval owner, I first think of the Great Wall 4D20.
<h1 class="pgc-h-arrow-right" data-track="4" > engine source</h1>
In the past two years, the domestic passenger car market can not be described as bleak, but in such a market environment, there are also car companies that have performed differently, SUVs and pickup trucks have blossomed in many ways, white cats, big dogs, cannons and other Internet red models are innovative, and innovative platforms such as lemons and tanks continue to establish their scientific and technological image, which is the most moist Great Wall in a number of independent brands.
Speaking of the engine supplier of Great Wall 4D20, its predecessor is Baoding Great Wall Internal Combustion Engine Manufacturing Co., Ltd., which was established in May 2000 and is a wholly-owned subsidiary of Great Wall Motor Co., Ltd.
In June 2018, Hive Yichuang Technology Co., Ltd. was established, and Great Wall Motor's former internal combustion engine manufacturing business was merged into the company, and became one of its four major business segments (power system, electric drive system, intelligent steering system, and transmission system). Before that, the Great Wall engine was basically only sold domestically, and the establishment of The Hive Yichuang was like opening the cage, making its engine products more open to major automobile manufacturers at home and abroad.
Hives are easy to create
< h1 class="pgc-h-arrow-right" data-track="67" > first 4D20</h1>
The 4D20 was originally called "Lvjing 2.0T" when it was first launched, and on November 12, 2010, Great Wall was first released in Baoding, and first paired with haval H5 and Fengjun pickup trucks.
At the beginning of its birth, Lujing 2.0T adopted the following advanced technologies:
VGT variable section supercharger: Produced by BorgWarner, according to the engine operating conditions, that is, the load and speed of the vehicle, the supercharger performance can be intelligently adjusted through the vacuum actuator, and higher booster pressure can be obtained at low speeds and the supercharger overspeed damage can be avoided at high speed. It can be said that this technology is the biggest highlight of the 4D20 engine, for cost considerations, most domestic diesel engines today still use ordinary vent valve superchargers.
- Dual overhead camshafts: Compared to the side camshafts, the overhead camshafts can achieve higher engine speeds, which in turn achieve higher power.
——Preheating plug in-cylinder heating: Compared with the intake heating grille technology, the small engine uses a preheating plug, which can achieve a lower starting temperature and better adapt to the cold environment of the northern winter.
——Electronically controlled high-pressure common rail fuel system: Delphi production, 1600 bar oil supply pressure (also said to be 1800 bar), the fuel atomization effect of the high rail pressure is better, the oil and gas mixture is uniform, and the combustion is more complete.
——EGR exhaust gas recirculation system: the use of electronically controlled EGR valve, can achieve national IV emissions.
--Timing belt: located at the front of the engine, the noise is lower than that of the gear drive or chain drive, and the whole vehicle is more comfortable. However, the timing belt needs to be replaced every 80,000-100,000 kilometers, which increases the maintenance cost of customers.
——Secondary balance mechanism: effectively reduce the two-stage reciprocating inertia force of the four-cylinder engine, reduce vibration and noise.
——Hydraulic tappet: the valve clearance is always maintained at 0 through the oil pressure, which realizes the maintenance-free life cycle and avoids the impact noise of the rocker arm and the valve.
Due to its excellent quality, in 2010, the Lujing 2.0T engine was rated as "China Heart's Top Ten Engines in 2010".
Since the first 4D20 mass production so far more than ten years, 4D20 continues to upgrade, there are 4D20B, 4D20D, 4D20E, 4D20M, 4D20T and other versions, respectively, supported in Haval, Fengjun, Great Wall Gun and other models, here focus on the two most distinctive.
<h1 class="pgc-h-arrow-right" data-track="68" > double-supercharged 4D20T</h1>
The 4D20T is the highest-end version of the 4D20 series, which was first ignited in 2013, but was not officially released until 2017, and is mounted on the haval H9, which is also the highest-end version, which shows the difficulty of development.
The biggest highlight of the 4D20T is the use of twin-turbocharging technology, which is used for the first time in a small diesel engine in China, so that the power of the diesel engine reaches 140kW, and the maximum torque reaches 420Nm, which is comparable to 2.5L or even 3L of ordinary diesel engines. As far as Sir Li knows, among the domestic small diesel engines, only the Great Wall 4D20 and SAIC Π products have a double supercharged version.
The booster effect of the supercharger is directly proportional to the difficulty of development, and here is a simple comparison of several boosting techniques. Ordinary vent valve supercharger is the simplest and most common, this kind of supercharger can automatically control the exhaust gas flow into the turbine according to the intake pressure, although automatic but not intelligent; VGT supercharger is relatively complex, can intelligently control the size of the flow section as needed, but the development needs to be calibrated, that is, tell the engine control system, in what conditions the flow section needs to be opened to how big; double supercharger has a large and a small two exhaust gas turbochargers, the effect is the best, but because of the need to calibrate the three working states of the two superchargers, The amount of work and difficulty of calibration is greatly increased.
Briefly speaking of the working principle of double supercharging, as the engine working speed and load increase, the dual supercharger can work only with a small supercharger, two large and small superchargers at the same time, and only a large supercharger can be switched in three states. Small supercharger inertia is small, smaller exhaust gas flow can blow it for pressurization, sensitive response, if you often drive in the city, low speed and frequent acceleration and deceleration, small supercharger effect is good; but if you often pull heavy objects to run the provincial highway high speed, small supercharger will be too high and destroyed, at this time the use of large supercharger, you can produce a higher pressure booster without overspeeding.
Of course, there are three-supercharged or even four-supercharged diesel engines abroad, and interested friends can see the extended reading of the following article. Later, Sir Li will open a separate "Li Solution Technology" series to introduce these several pressurization technologies in detail.
<h1 class="pgc-h-arrow-right" data-track="69" > 4D20M of the electronically controlled VGT</h1>
The double supercharging is accompanied by some defects in improving the power, on the one hand, the increase in cost and selling price, and on the other hand, the reliability problem caused by high power. I don't know if it is for these reasons, the current Haval H9 and even the entire series of New Wall models have not seen the figure of 4D20T.
Sir Li checked from the official website of the Great Wall, and at present, both Haval and the fuel version of WEY are only equipped with gasoline engines. The Great Wall pickup truck, including the cannon and the wind jun, has two configurations of gasoline and diesel, of which the diesel version is matched with 4D20M.
From the perspective of power, 4D20M is a product second only to 4D20T in the 4D20 series of products, and the following technical measures are mainly updated:
——Electronically controlled VGT supercharger: Garrett (that is, Honeywell) production, compared to the original lujing 2.0T, although it still uses a VGT supercharger with variable cross-section, the vacuum actuator is upgraded to an electronically controlled actuator, and the supercharger control is more rapid and can respond to changes in the working conditions of the car in time.
- 2000 bar fuel system: the rail pressure is further increased, which can achieve multiple injections, burn more fully, improve noise levels, and obtain lower fuel consumption and lower exhaust emissions.
Variable intake vortex: after the air enters the engine cylinder, the spiral movement, the intensity of the spiral movement is called the vortex ratio. The eddy current ratio is the opposite of the flow coefficient that represents the capacity of the intake air, and the larger the eddy current ratio, the smaller the flow coefficient. The engine needs less air when running at low speed, we hope that the vortex ratio is large at this time, so that the fuel and air are fully mixed; more air is needed when running at high speed, and we prefer that the flow coefficient is large at this time, so the vortex ratio is smaller. The eddy current ratio of ordinary diesel engines is not adjustable, and the 4D20M optimizes the engine performance through structural design so that the eddy current ratio can be adjusted between 0 and 1.2.
——Lightweight: The wall thickness of the cylinder block is reduced to 3mm, and the weight reduction scheme such as plastic intake manifold is adopted, and the weight of the whole machine is reduced from 215kg of Lujing 2.0 to 192kg.
<h1 class="pgc-h-arrow-right" data-track="70" > the main parameters of the engine</h1>
Finally, the main parameters of the 4D20 engine are summarized, as shown in the following table.
The outer characteristic curve of the 4D20M is shown in the figure below, where the solid and dashed lines represent two different versions of torque.
<h1 class="pgc-h-arrow-right" data-track="71" > conclusion</h1>
Great Wall Motors can dominate the pickup truck and SUV subdivision models, and the 4D20 diesel engine has also made a lot of contributions. Although there is no longer a sharp edge of new products, 11 years of precipitation and accumulation have brought maturity and stability to 4D20. Overall, 4D20 is still highly competitive, but to meet the future emission regulations of China VIb, it still needs a major upgrade.
How do you evaluate Great Wall Motors' engines and cars? Welcome to leave a message to discuss.
If this issue is helpful to you, please pay attention to and like it. I'm Sir Lee, a friend who accompanies you in an in-depth understanding of the engine.
<h1 class="pgc-h-arrow-right" data-track="73" > further reading</h1>
Foreign advanced diesel engine part IV: BMW engine N57S with three superchargers
Foreign advanced diesel engine part V: the wayward BMW B57S, there are four superchargers
<h1 class="pgc-h-arrow-right" data-track="74" > article references</h1>
【1】 Great Wall Motor's official website
【2】 Hive Easy Creation official website
【3】 Great Wall Lvjing 2.0T, Baidu Encyclopedia
[4] A brief history of Great Wall Motors engines: from external procurement to self-production of 10 million units, are they forced by Brilliance? Car totem
【5】 New power source Great Wall Lujing 2.0VGT diesel engine disassembly, Autohome
【6】 General introduction of 4D20 engine, Baidu Library