At Denrai Kohbo, we have been working to faithfully realize the abundant images that architects, sculptors and designers have in mind through prototype casting technology that we have improved over the years.
Our foundry in Kisshoin, Minami-ku, Kyoto City have casting facilities for pieces and products ranging from small to large and a state-of-the-art automated casting system called V-PRO (Vacuum Molding Process). This page, we invite you to see our head office and factory through photos of the processes with a brief explanation of the finished cast products at the V-PRO facility.The factory is located within the same vicinity of the head office.
Denrai Kohbo was established in Kyoto, which has 1200 years of history. We are involved in manufacturing products by upholding and developing the casting technology that Kobo Daishi Kukai introduced from the Chinese Tang Dynasty under the motto "Creating products that we can be proud of in the coming ages." The V-process line for aluminum casting, which we are particularly proud of, is an integrated production system covering the stages from the preparation of wooden molds and the feeding of raw materials up to the finished casting of base materials, all the while following the basic philosophy of environmental consideration. We work hard night and day, aiming not only to assure safet but also to provide QCD requirements (Quality, Cost and Delivery) that are superior to any other manufacturer. We believe we offer products that can completely satisfy customers' requirements. Please feel free to visit our factory. We look forward to welcome you.
The manufacturing processes for aluminum casting in the V-PRO facility are as follows. First, a prototype is placed on a plate called a stool, which has a precise flat surface.
The stool is then mounted on the turntable, as shown in the photo on the Bottom (1) and it is automatically replaced with a sand mold. At this time, in the V-PRO facility, the prototype patterns are transcribed on sand wrapped by a thin film pouch and the sand is solidified by vacuuming the film bag, just like a compression bag.Usually, this process is achieved by mixing chemicals with the sand to solidify the sand to form a mold, which takes several hours. With our vacuum system, on the other hand, the sand can be solidified automatically within several tens of seconds. The photo on the left is a sand mold that has been transcribed. * V-PRO: Vacuum Molding Process°”
The sand mold (2) is used as the lower mold and an opposing sand mold is placed on the sand mold (2). At this time, the portions to form the patterns are hollow. Aluminum alloy heated to about 800 °ŽC is then poured into the hollow area as shown in Photo (3).Conventionally, the process is carried out manually by scooping up the molten alloy and it was an everyday occurrence that workers get first, second or third degree burns. The current V-PRO facility is an advanced system that enables automatic pouring of molten aluminum through the computerized control system. [Photo (3)]
After filling the hollow area of the mold with molten aluminum alloy, the mold is sufficiently cured until the metal cools and solidifies.
The photo on the left shows the emergence of the formed product from the sand mold. The vacuum formed sand is restored to dry, fine sand when exposed to atmospheric pressure and can be recycled for repeated use. This is another advantage of the V-PRO facility.
Manufacturing under the Denrai Brand Photo (5) shows the finish work, in which protrusions at the joints of the products and the pouring inlet are scraped off and deformations, if any, are corrected. The finish process adds a soul to products. We carefully finish the products one by one and sow the seeds of the manufacturing spirit of Denrai Kohbo.The head-office factory incorporates a painting booth, an atelier center for product development and a laboratory for the experimental production of FRP products, in addition to casting facilities for aluminum casting. We also have exhibition space for our new brand, Dea's Garden situated at the head office where our customers visit to look at our products. We also established an aluminum casting plant and an FRP plant in the Philippines.