Recently Great Wall Motors announced that its first intermediate & high-end urban-type automobile SUV-Haval H6 is scheduled to roll off the internationally art-of-the-state production line of its new Tianjin plant in late August. Owing to this painstaking work Haval H6 as well as its world-class production equipment and technological facilities, the Great Wall Motors Tianjin plant, which is the most advanced in China, has attracted outsiders’ wide attention with the approaching of the rolling-off day.

Hundreds of Robots in the Production Line Ensure High-quality Haval H6

In auto production processes nowadays, the introduction of robots increases the precision of technological processes and decreases the influence of deviations caused by human factors on high-quality.

Over a hundred of robots are equipped in the four workshops in the Tianjin plant including punching workshop, welding workshop, coating workshop and assembly workshop. These high-end robots purchased from Sweden, Japan, Italy, Switzerland and Spain really deserves to be called “a banquet of robots”. Looking around entire car enterprises in China, you will find that such a top-scale use of so many high-tech robots not only guarantees that the quality of each core piece of Haval H6 meets the international standard, but also realizes the systematic improvement of entire car assembly quality, making the precision, durability, comfortability, reliability and the like of the product undergo a great-leap-forward improvement.

In the punching workshop, the punching line is of close-type production mode, and nearly no worker is needed to participate in the production. In the B01 code-named full automation production line, a couple of Sweden ABB robots are used in the turning and transmission unit. The first pressing machine of A02 punching line adopts German NC hydropads, which is the first practice in China, and the automated equipment of this production line are single-arm manipulators introduced from Switzerland, and these precise and advanced equipment guarantee the production precision of the pressed parts of Haval H6.

The design and manufacturing of the main and repair welding lines for car body in the welding workshop in the Tianjin plant are both implemented by ABB Group, and the whole production line has 30 stations and equipment and 27 robots in total. The 9 general assembly stations for ABB robots adopt a specific Framer form , and realize the assembly of the four parts of the left/right side wall assembly fixtures, floor assembly positioning fixtures and coping assembly positioning fixtures, as a result, the car body's structural steel strength and precision of Haval H6 increases greatly.

The spray coating of Haval H6 is conducted by 26 YASKAWA wall hanging-type automatic spraying robots, and its paint utilization ratio can reach 90%, and in addition, its paint, high voltage and rotational speed all reach high-precision control. The width of the spraying workshop is only 4.5 meters, which is one meter lower than that of the traditional design, and the new design not only increases the quality of the coating layer but also increases the spraying quality and material utilization rate. In the general assembly course, the glass-gluing technology for Haval H6 is completely conducted by robots, and if the deviation of gluing width or thickness exceeds 1 mm then it will be discovered by the robots automatically, and such a precise control ensures the high efficiency, precision and quality of the assembly work.

“Zero Debugging” Ensures Haval H6's Manufacturing Quality Precisely

“Zero Debugging” is a quality management mode that must be implemented rather than a simple concept. This is a quality management project in the lean manufacturing in the Great Wall Motors Tianjin plant, and its objective is to guarantee that each and every Haval H6 can leave the production line with "Zero Problem". It can be said that the rolling-off standard of the "Zero Debugging" aims to solve all the problems on-line.

Now we take the assembly workshop as an example. This is the final working operation in the entire car manufacturing process, and also the general customspass for quality control. There are over 20 customspasses in the assembly line in total, and the records of the new car's passing through the customspasses will be summarized for one time every 30 minutes, and then technical staff will go to the spot to solve the problems directly.

ANDON systematic distributions, ANDON ropes, ANDON handholds and ANDON electronic screens are distributed at various stations of the general assembly line, and during the production process, so long as the ANDON rope is hauled down, the electronic display screen will make an automatic alarm, and simultaneously it will indicate the station position in detail. In this visible management mode, the managers and quality principals can have the working operation in hand.

Accurately speaking, the treating process of Haval H6's quality problems is a quality improvement process. The principal of the assembly workshop of the new Tianjin plant made an introduction like this: this control method ensures the settlement of all the problems in the first time; what's more, the system evaluation and improvement are used to transmit quality management and improvement information to all processing operations, making the product's quality improve unceasingly.

The Tianjin plant adopts advanced equipments to form a quality management guarantee system by starting with each and every part, component and integrated unit, which improves the precision of the manufacturing process of the entire car, and builds Haval H6's high quality of each part and the whole body, reducing the probable probability of failures in the future use.

Precision of Manufacturing Quality Increases by 200 Times

During the course of manufacturing Haval H6, flexible and servo-type precision production can be found everywhere, and especially the improvement of process precision ensures the consolidation of the quality of the entire car. For instance, the working frequency of the medium frequency welding machine used for Haval H6's welding process can reach 1000 Hz and the machine can change the wave form of the alternating current to linear wave forms close to direct current, which greatly reduces differences between different soldered points, and it increases by 200 times than the 50 Hz-frequency welding machine used in traditional entire car manufacturing, so as a result the welding strength increases greatly; the nine ABB robots in the general assembly position of the welding line adopt servo electrode holders, realizing a more accurate positioning than that of traditional pneumatic electrode holders, and guaranteeing the highly efficient completion of welding (pneumatic electrode holders impulse the cylinder by compressed air/servo electrode holders realize control through servomotors).

In the edge-rolling step, traditionally, the bound edges of car doors are disposed of by traditional pressing machines, and this method can make a certain impact on surrounding parts, while this step for Haval H6 is conducted by edge-rolling robots, and the robots adopt a flexible wrapping method to encase the door inner panels with door outer panels to avoid minor deformation of surrounding parts and components caused by the pressure shocks.

Human-oriented Care Boosters Quality Improvement

Human-oriented care in production is not only an international popular concept, but also a production attitude towards the product quality.

Low-carbon and environmental protection are the important embodiment of human-oriented care, and during Haval H6's production process green environment-friendly materials are used to make cars produce little noxious gases or emissions in their later usage, and this is an embodiment of dual responsibilities for both working personnel and consumers. The paint workshop of Tianjin plant adopts an environment-friendly and energy-saving green design concept, and water based paint, a kind of environmental protection coating material is used in the spraying workshop to reduce the discharge of VOC (organic gaseous waste) from paint workshop, therefore the discharge amount of VOC reaches the international standard. The organic gaseous waste incinerator units in the workshop are imported from Germany, and these incinerators integrate gaseous waste incineration and heating supply into one body, and drain the air at the auxiliary workstations to the paint spraying air-mixing room by using re-circulated air and then use the air there, so as to realize the reutilization of the discharged air energy source.

The new Tianjin plant really spares no effort in giving human-oriented care. The general assembly workshop adopts AGV integral type lifters, and these lifters are manually controlled to lift the workpieces to mounting positions. In this way, not only the work efficiency and operation precision are increased, but the labor intensity is also reduced. It is learnt that all the parts and components weighing more than 15 kg in the plant are transported by mechanical sub-arms, which greatly increase the work efficiency and guarantee the control of accurate in-position and frequency of the transported workpieces.

Reducing production strength greatly by using high-tech equipment and selecting environment-friendly material is not only an embodiment of human-oriented care, but also an embodiment of meticulousness of quality control, and all these measures together guarantee the uninterruptedness of high-quality of the product, and finally benefit the consumers.

With the progressive development of automobile industry, people are becoming more and more familiar with platform production in automobile manufacturing. As an important guarantee for quality of model of car, production and workmanship have become one of the most important factors influencing the quality of an entire car. Basing itself on the tradition of “quality foremost”, the new plant in Tianjin provides the most essential and solid guarantee for the high quality of Haval H6, a strategic model of car.