2. Plant Tour
- Electric carts used for plant tour -
Given the size of this plant, we used electric carts for transportation and toured the (1)Engine plant, followed by (2)Vehicle plant and (3)Vehicle warehouse/trains.
On the premises of the plant, there is also the Regional Training Center, where master trainers that had been educated at the Global Training Center in the Oppama plant, coach employees.
- Inside the Engine Plant -
A mix production system, where multiple types of engines are produced on the same production line, is adopted for those engines produced in large quantities in an effort to enhance efficiency. Using the same facilities as the Yokohama plant in Japan, these lines provide for flexible responses to changes in settings, such as size due to engine improvements and other factors.
In contrast, the caravan production system, where one engineer is responsible for multiple production processes, is adopted for those engines which are produced in small quantities and requires only a few hours.
Manual engine assembly processes implement efficiency measures, such as Kit-supply that providing a complete set of necessary parts in one box to prevent mistakes and placing cushioned mats on the floor to ease the burden for workers.
Since problems are detected at quality assurance facilities within each process, only 75% of completed engines are randomly sampled and inspected. Hopefully, this ratio will be further reduced while maintaining the same level of quality.
- Inside the Vehicle Plant -
The first processing stage is press forming, where pressing machines using dies stamp out steel plates. Since pressing machines and dies are expensive, press forming is also carried out by the Cuernavaca plant.
The steel plates are then transported to vehicle body processing, where they are welded and transformed into vehicle bodies. At this stage, cost-cutting is achieved through leveraging competitive labor costs and manual subassembly which is automated in Japan, thereby reducing facility investment. As a result, the automation ratio at this stage is 72%, whereas the ratio of the Oppama plant is 92%.
Automated processes are designed to reduce facility error through the introduction of standard facilities known as the Nissan Integrated Manufacturing System (NIMS) line.
After the body processing stage, the vehicles move to the painting stage and then the assembly stage. Due to the requisite cleaning of paint hoses, alternating colors at the painting stage results in stoppages. Therefore, the plant aims to reduce such losses by processing up to 17 vehicles with the same color.
The plant retains its top position in production cost per unit through a cost-cutting activity known as integrated factory automation (iFA), which was integrated in the assembly stage in 2007. Initially introduced at the Oppama plant, iFA combines smooth material flows with low-cost automation known as ''Karakuri'' (Japanese traditional automated mechanism).
- Freight trains with vehicles waiting for loading -
Completed vehicles are stored in vehicle warehouses. In order to efficiently conduct maintenance on vehicles prior to delivery, Japan and US built vehicles for sale in Mexico are also stored in these warehouses.
The vehicles are transported daily by scheduled trains. Depending on the destination, it takes approximately one week to 20 days to reach the US. On the return trip from the US, the trains carry back US-produced vehicles for the Mexican market.
There are two types of trains, double-stack and triple-stack trains. The efficient triple-stack trains are used when possible. However, two-stack trains are used if the height of the vehicle is too high.
Part 4. Summary
In order to increase awareness of our cost reduction efforts, we introduced specific measures implemented at the Aguascalientes plant, despite the difficulty in with words alone.
Although we focused on cost this time, Nissan is promoting the Nissan Production Way (NPW), and implementing improvements and reform in quality, cost and delivery time at its plants worldwide in order to meet customers' needs. We will continue to report on various plant activities in future issues.
This is the conclusion of “Visit to Nissan Mexicana”, which was also the first theme of Inside NISSAN. We will regularly report on “the inside of Nissan Motor”, so that you can obtain a deeper understanding of Nissan. We hope you enjoy our report.