"Go-ahead Technological Revolution", Talk to Powertrain Engineer of HAVAL H6
2018 is a strategically important year for GWM. As a down-to-earth automobile enterprise, GWM set its first goal this year to build a technological brand. GWM, adhering to the principle of "Low-key Life, High-profile Work", started independent R&D and production of power system a dozen years ago. Up to this day, GWM has made significant breakthroughs in numerous automobile technology fields, particularly in powertrain field where a technological revolution has been completed successfully. The self-developed 1.5GDIT engine is awarded as 2017 "Chinese Heart" Annual Top Ten Engines and the 7DCT (wet-type) as the World Top Ten Transmissions.
On April 3, GWM took new Haval H6 equipped with 1.5GDIT as a representative and invited a number of media friends throughout the country to share "Go-ahead Technological Revolution" of powertrain.
Go-ahead Technological Revolution - Breakthrough in Powertrain
During the event, the Chief Engineer in charge of product technology shared the technological revolution and stories behind HAVAL 1.5TGDIT engine (with 92 patents) and self-developed 7DCT (wet-type), fully demonstrating GWM's independent R&D capability and international level of products. From GW4G15B+6AT to GW4B15+7DCT, it is not just a simple power upgrading, but a revolution from EG platform to new EB platform, and more precisely, an all-around revolution of development idea of powertrain.
Breaking down Patent Barriers and Master Top Engine Technologies
Peak torque of 285 Nm generated at 1400 rpm and a maximum power of 124 kW are undoubtedly a group of top power data throughout the world. Such excellent performance is due to the superior technical configuration of 1.5GDIT engine.
Moreover, a top technology GWM has developed is the most important - continuous variable valve lift (CVVL) technology. GWM is very proud of this technology, which makes GWM an "Ace" among independent brands. Throughout the world, only BMW, Infiniti and Fiat have mastered similar engine technology, while VVS in Audi vehicles and i-VTEC in Honda vehicles are just capable of grade regulating. During development, engineers completed the design of the whole structure and the development of relevant test equipment based on the mechanical principle of valve lift. In order to ensure the reliability in actual use, GWM designed a series of extremely rigorous test. Just in a single test, the motion of relevant part has been repeated for over 600,000 times, equivalent to the total number of motion times of such part after the vehicle has traveled for 150,000 km. The CVVL technology has not only reduced fuel consumption by 8.4% but also increased the maximum power and peak torque by respectively 12.7% and 35.7%, which has demonstrated GWM’s prominent independent R&D capabilities.
In the meantime, the efficient combustion system can also provide technical support for the outstanding power performance. An airway with tumble ratio of 2.3 and 200 bar high-pressure central injection system and other parts are designed and equipped inside the 1.5GDIT engine to enable the generation of turbulent kinetic energy and rapid combustion, thus reducing overall fuel consumption to 6.8 L / 100 km.
Besides, with 92 patents and independent intellectual property, the 1.5GDIT engine also benefits from an NVH design that is superior to that of mainstream JV brands. With the help of suspension oil injector, EVO high-pressure oil pump, high-rigidity parts, fine-pitch silent chain and other designs, the NVH performance during the whole accelerating process of the engine turns out to be very impressive, especially under common rotation speed.
This performance cannot be achieved without GWM’s world-leading NVH laboratory. The independent chamber in room structure, 1,600 damping shock absorber, and plate-based noise control technology owned by FAIST can reduce the background noise to as low as 16 dB, with a static frequency of 40 Hz and an effective sound field radius of 3 m, thus ensuring the accuracy of the test result.
A good design alone does not make an engine a popular product. Outstanding reliability is also required. The engine has received bench test for tens of thousands of hours and vehicle reliability test for over one million kilometers.
The outstanding performance of the engine is supported by the world's leading Power Test Center of GWM. The Power Test Center is established with an investment of about RMB 480 million. With 80 imported benches, the center has become a nationally recognized first-class engine laboratory where comprehensive test and analysis on such aspects as combustion development, performance calibration, emission, NVH and Benchmark can be conducted.
First Self-developed Mass-produced 7DCT of Chinese Brand in Real Sense
A transmission efficiency of over 95% is one of the highlights of the first mass-produced 7DCT of Chinese brand. One of the reasons for the data is the employment of energy consumption reduction program at a system level, including the use of parts such as low-friction bearings and low-friction rubber oil seals. Meanwhile, lubricating oil with minimum viscosity is used for this 7DCT to reduce flow resistance and improve the transmission efficiency and fuel economy. In order to maintain the maximum transmission efficiency, required, active and forced control over vehicle fans, electronic water pump and transmission oil pump are provided to achieve efficient cooling and keep the operating temperature of transmission within an optimized range of 70℃-90℃.
In order to optimize the NVH performance of the vehicle, the design of NVH performance for 7DCT is carried out based on the idea of "design for quietness and transmission for power". In the R&D stage, the engineers ensured the optimized NVH performance of the transmission by means of acoustic stimulation, analysis and optimization of road spectrum and TPA tests under various kinds of operating conditions and vehicle-level system coupled simulation of fluid noise/vibration fatigue.
The transmission laboratory supporting the 7DCT is also a first-class laboratory. The Transmission Test Center, with an investment of about RMB 220 million, covers an area of 2,100㎡. It has 20 test benches for transmission assembly and 15 test benches for parts. With those facilities, tests covering single part, transmission and power assembly can be conducted in accordance with a complete test specification system.
If the engine is seen as the heart, then the transmission can be regarded as the artery and it is responsible for transmitting the strong power generated by the engine out. In order to ensure the reliability, the accumulated bench test time for 7DCT transmission is over 14,000 days, equivalent to about 38 years. In the meantime, a vehicle test with a total traveling distance of 7.53 million kilometers has been conducted on the transmission, which was equivalent to 188 times the length of equator. The vehicle was traveling in areas with extreme environment, such as plateau, high-temperature area, high-humidity area, low-temperature area, mountain road and desert.
In order to perfectly combine the two power cores, the engineers have completed a vehicle matching test, with a total traveling distance of 1.24 million kilometers. It is because of such long-term and rigorous tests that new Haval H6, characterized by faster speed, lower fuel consumption, safety and good quality can be actually owned and appreciated by the consumers.
Factories Rivaling Luxury Brand and Perfect Technology in Manufacturing
Engines with advanced technology shall be manufactured by factories with excellent equipment. Xushui Power Division is a high-performance engine production base newly established by GWM. It covers an area of 67,000 m2. The workshops in phase I cover an area of 40,000 m2. They were constructed in March 2011 and put into mass production in December 2013. The design annual production is 450,000. The workshops in phase II cover an area of 27,000 m2. They were constructed in November 2015 and put into mass production in October 2016. The design annual production is 280,000. The main product is 1.5GDIT engine for models such as Haval H6.
In the factories of Xushui Power Division, intelligent, informationalized, environment-friendly and completely automatic manufacturing of engine cylinder block, cylinder head and crankshaft is achieved from workblank to finished product. The processing equipment used in the factories is all imported. European processing equipment brands such as GROB, COMAU, DMG and HELLER are used with automated trusses and automatic roller to complete line processing, so as to make manufacturing precision as high as 1/70 of the hair diameter.
The operating standards of factories for transmission manufacturing are also superior to industry standards. They can rival the factories of luxury brand vehicles. The Automatic Transmission Division in Xushui is a high-performance transmission manufacturing base newly established by GWM. The planned area of factories is 145,000 m2 and the planned annual production is 1,000,000. The construction of those factories is divided into two phases. The workshops in phase I cover an area of more than 60,000 m2. They were constructed in November, 2015 and put into mass production in March, 2017. The designed annual production is 500,000. The product will be matched with GWM products of platforms P2, P3 and P4, covering more than 30 vehicle models.
The Automatic Transmission Division is equipped with dry cutting technology that is quite rare in China. The machine tools made in Switzerland and Germany can not only cut the workblank accurately but also collect and treat dust, thus making contributions to protecting the environment from the very beginning of the manufacturing process. Hobbing-shaping processing technology, a combination of traditional hobbing method and shaping method, is employed in gear manufacturing. The manufacturing speed and accuracy will be very high. Ultrasonic cleaning technology, a very advanced technology in China, is also employed. In addition, the rigorous testing standards are used as well. For example, there are cleanliness testing rooms up to European standards and rooms for accurate measurement of error parameters such as surface roughness and flatness. Because of these processing technology and testing processes, the pass rate of parts and components can be as high as 98%.
Dedicating to Technology Research and Making Progress Every Day
Undoubtedly, the reason why GWM can achieve so much in the market and become the leader in Chinese brand and technology is because of its insistence on independent research and development and continuous technological breakthroughs. In the future, GWM will continue to be insistent on independent research and development, make progress every day and promote the continuous innovation of Chinese brand and technology.