In the fifth season of "Guangzhou Automobile Toyota One-day Craftsman Quality Open Day", we once again went into Guangzhou Automobile Toyota Nansha Factory to explore its excellent quality control system and the mystery of product quality under the TNGA framework, and to find out the quality ingenuity of every car and every component.
High quality star production line
The third production line we visited can be said to be a "star production line". The one-time qualification rate of its production line, that is, the rate of vehicles leaving the factory directly with certificates after assembly is off the assembly line reaches 99.0%, which is nearly 10 percentage point higher than the industry average; The defective rate of the whole vehicle inspection is 0.0 1, that is, there is only one defect (referring to the appearance defect, including dirt, etc.). ) per 100 vehicle. At the same time, the essence of GAC Toyota's quality management is also poured into its suppliers. In 20 19, the part defect rate of GAC Toyota suppliers was 0.36PPM, that is, only 0.36 parts out of 1 10,000 parts were defective. These figures directly reflect the high level of quality control.
Quality is formed in the process.
Only when the methodology is correct can we achieve excellent results in concrete implementation. GAC Toyota has a popular saying that "quality is made in the process, not tested", which is Toyota's methodology for quality control. Here, I would like to mention the core of quality management of GAC Toyota-since the end of the process, it is required to ensure the quality of the process, let people and machines judge the quality of the process, find problems in time and improve them to prevent defective products from flowing to the next process. While many enterprises are still relying on results-based management to control the quality through after-the-fact inspection, traceability and re-checking, GAC Toyota's quality management system has long achieved "first strike is the strongest", that is, all problems are found and solved in the process, and defective products are not brought into the next link, thus ensuring the overall quality control. This methodology is indeed advanced, and the effect is very good in practice.
In order to ensure "self-completion", GAC Toyota also applied wireless Anton device in the production process, which can visually display the working status of each process. Once there is a problem in a certain process, the system will give a warning, stop the production line when necessary, and relevant personnel will analyze and solve the problem to further improve the efficiency of quality management.
Some measures to ensure the quality control of aluminum plate of Willanda car body
In the stamping workshop, the biggest difference between GAC Toyota and other car factories is that more than 90% of stamping parts are produced by themselves, which is about 2 times more than the industry level. Large stamping parts such as floor, front fender, wheel cover and longitudinal beam, and small stamping parts such as front and rear sub-frames and C-pillar reinforcements are all made internally. The advantage of the internal system is that it can guarantee the quality most effectively. The highest strength of these stamping parts reaches 1 180MPa, and the precision, surface quality and formability meet the requirements of Toyota's highest global standards, which is more secure.
Here, we would like to focus on the aluminum plate used by GAC Toyota for the first time on the body of Willanda. As we all know, aluminum is a car body material that car companies are keen to use in recent years because of its lightweight effect. It can not only improve the handling performance, but also effectively reduce fuel consumption. Of course, better use effect also means higher manufacturing difficulty and cost. The difficulty of aluminum sheet stamping quality management lies in its timeliness, which should be used within the specified time; It has no magnetism and needs a special blowing device to separate materials; Its ductility is low, its stamping formability is poor and it is easy to crack; In addition, it has low hardness and is more sensitive to foreign bodies than iron.
Guangzhou Automobile Toyota adopted these measures in the stamping process, which effectively ensured its quality control. Firstly, the grid die technology patented by Toyota is adopted to process 1mm grid grooves on the die surface, so that foreign matters can fall into the grooves, avoid contact with the plate, and reduce the pitting of the aluminum plate.
Secondly, its trimming/flanging knife adopts DLC coating, which is similar to diamond coating. Strong hardness and smoothness, high adhesion resistance, not easy to sinter, can reduce the generation of aluminum powder and reduce pits. In addition, GAC Toyota also made its own dust collection device, and installed a dust collection device on the mold to suck away the aluminum powder produced during trimming in time to reduce pits and indentations.
Mystery of welding assembly of high strength steel
Guangzhou Automobile Toyota TNGA adopts a large number of high-strength steel, and the body frame adopts ultra-high-strength hot stamping steel, which greatly improves the overall rigidity of the body and has higher safety and driving performance. Such as 202 1 Lei Ling, 42% of ultra-high strength steel is above 590 MPa, and the highest strength of the whole vehicle steel reaches 1620 MPa.
The challenge of manufacturing quality control of high strength steel mainly lies in welding process. There are more than 5,000 solder joints on TNGA cars such as Lei Ling, which is quite difficult compared with more than 2,000 solder joints of other brands. GAC Toyota relies on several unique technologies to overcome these quality problems.
In the welding workshop, in the past, the traditional practice was to use different fixtures for different models. For example, if six models are produced, there are six sets of fixtures, which are switched according to the models. At present, the whole line adopts Toyota's unique multi-vehicle assembly fixture, which is universal and seamless, realizes flexible production, and the precision control range is within 0.02 mm This is also the latest cutting-edge technology developed by Toyota, which is not available in other car factories. GAC Toyota is also the first model adopted by Toyota.
Another top-notch equipment is Toyota's unique electrode head forming machine, which is Toyota's patented technology, and every spot welder is equipped with it. Every time the robot welds, the electrode head will be polished in the molding machine, so that each work will be kept in a brand-new state, thus ensuring that each solder joint is a standard solder joint. While ensuring the accuracy of solder joints, the spatter is reduced, because the quality of electrode end points is stable, and the phenomena such as poor nugget, solder joint burr and poor surface quality particles caused by spatter are reduced.
In addition, on-line laser detection is used to measure the laser accuracy of the front, side and tail of the vehicle, and take photos of the solder joints. If the accuracy does not meet the preset range (within 1.5mm), the machine will automatically give an alarm, and relevant personnel will intervene to solve it to prevent the defective products from entering the next process.
Paperless iPad introduced into testing workshop
In the assembly workshop, GAC Toyota is the first factory in China to adopt the mode of chassis transverse body transportation, which has the advantage of intensive space, saving 50% space compared with the traditional vertical production line and reducing the moving distance of operators during the operation. At the same time, the chassis is tray type, which can quickly switch trays and realize Tonghua production.
At the same time, it also has a complete quality traceability system. Every entrance and exit of the assembly line has a coating image detection system, which can automatically take pictures and wirelessly transmit the detection data to the background computer. After comparison, we can know whether there are scratches, dirt and other quality problems on the body surface, and save the data for future quality traceability.
In the process of body surface inspection, GAC Toyota introduced a brand-new design concept of light shed, keeping the illumination of 2000-3000 lumens, consistent with the outdoor sunlight of 35℃, restoring the real use scene of customers, and allowing operators to grasp the overall appearance quality of vehicles from the perspective of real customer experience when inspecting the appearance.
In the inspection line, we also see that the paperless iPad has been applied to the manufacturing process. In the past, it was time-consuming and laborious to check and confirm the detection line through paper forms. After the paperless iPad device was introduced, the operator visually compared the impact data of the real vehicle parts with the iPad, which improved the inspection efficiency. At the same time, when the operator checks the information of each car, it will be directly transmitted to the system through the iPad, and all departments can control the quality of each car in time through the background system, which greatly improves the efficiency.
abstract
After visiting the manufacturing technology of GAC Toyota, the biggest feeling is the powerful motivation and efficiency brought by the guiding ideology of "high quality comes from technology". The core of quality control management is "self-process completion", which enables the problems in manufacturing to be discovered and solved in real time, which not only improves the overall quality, but also greatly improves the efficiency. Thanks to such an advanced quality control management system, the quality of GAC Toyota TNGA products is really reassuring!
This article comes from car home, the author of the car manufacturer, and does not represent car home's position.