Quality Control : Operate, feel, verify

Glad that defects are found rather than cause disappointment when they occur

I am the Deputy General Manager of the Urahoro Test Site. Here, we test and evaluate construction machinery at the request of Hitachi Construction Machinery factories in Japan, Hitachi Construction Machinery Tierra, and other bases. We are given instructions from these sites on what kind of tests to conduct, and the instructions of each site are almost the same each time. Our role is to actually conduct the tests while confirming the schedule and methods, and give instructions to operators. We share with the designers and factories in advance what to focus on and what to evaluate in the tests.

Many of the machines brought to the Urahoro Test Site are products just before their release. Especially recently, design accuracy has improved and level of completeness increased, so major problems or fatal troubles rarely occur. Even so, defects may occur that are not apparent at the design stage and that cannot be noticed until the machine is actually used. The fact that such defects are found means that they can be addressed before they reach the customer, so I am glad that they are found rather than cause disappointment when they occur.

I am glad and find it rewarding when I hear that a machine that was tested here and released to the market has been well received with no malfunctions.

Safety and health first for both customers and employees

I am in charge of designing compact wheel loaders at Hitachi Construction Machinery Tierra's Development Center. I have only been with the company for a short period of time, having just joined in 2023, so right now I am mainly designing parts and so on. I not only maintain the machine during testing and respond to any problems that arise, but I also get on board as an operator to test driving and excavation.

In operation tests, we check whether any defects occur by running the machine for a long period of time in an environment similar to that of the actual job site where the machine will be used. I also drive the vehicle myself to confirm that the ride quality and operability are in line with the design. We can test the operability to some extent at the factory, but only at the Urahoro Test Site can we test the environmental conditions such as dust and uneven road surfaces similar to those at the actual job site. Working at the Urahoro Test Site makes me realize that there are many things that can only be understood by actually driving the vehicle and using it.

Since the time I joined the company, I have been taught that the most important aspects of construction machinery design are safety and health. This includes not only safety for our customers, but also the safety and health of our own people as a manufacturer. I believe that the emphasis on ride comfort in recent products is part of this philosophy.

Discovering true quality by actually operating the machine

Since joining the company, I have long been involved in the design and development of Ultra-large Hydraulic Excavators and Rigid Dump Trucks that operate in mines. I am currently a member of the Dump Truck Current Model Engineering Sec. Current design mainly deals with defects that occur in products currently in the market and to improve their quality, which is considered a job that supports quality after machines are delivered to customers.

Quality at manufacturers is sometimes broadly divided into “design quality” and “manufacturing quality.” Design quality is, of course, led by the design team to improve and enhance quality, but in the case of manufacturing quality, when it is difficult to ensure the expected quality at the manufacturing stage, the design, manufacturing, and quality assurance teams work together to deal with the problem, including design modifications.

We are currently conducting tests using actual Rigid Dump Trucks at the Urahoro Test Site to respond to requests from overseas customers. In recent years, the better performance of analysis tools and the sophistication of analysis technology have improved the accuracy of theoretical performance checks, but there are some performance and quality factors that cannot be understood without actually operating the machine. We believe that testing actual machines at the Urahoro Test Site is an important process for bringing unbreakable products to the market.

Performance is critical, but ensuring that machines are unstoppable is even more important

In my current department, I engage in the design of Ultra-large Hydraulic Excavators from the conceptual stage. In the development of new models, I sometimes visit job sites myself to ask operators, maintenance personnel, and administrative staff for their requests and opinions, which I feel is an important process for creating products that satisfy customers.

In the case of the Ultra-large Hydraulic Excavators I design, many are used overseas. However, the essence of approach to quality is the same overseas as it is in Japan. We manufacture industrial machinery, so our customers are looking for machines that contributes to their bottom line. Performance is important, such as the ability to dig a lot or perform a variety of tasks, but it is more important that the machine does not stop unexpectedly due to breakdown or malfunction.

In product development, we conduct design reviews among several departments to confirm the design details, and the corporate quality assurance group also provide data on past failures and problems that have occurred in the market to the design team. Recent models allow us to collect a variety of data on the machine, so we can get a detailed understanding of how the machine is actually used on the job site. I hope to continue such efforts in the future to provide products of even higher quality.