We satisfy various needs from undergrounding distribution products to hybrid power generation & telecommunication systems.
Doi Seisakusho Co., Ltd has been offering System Technology for many industries such as power and telecommunication, road, railway, constructions over 88 years. We continue our challenge to offer and propose "Better solution for better life". Doi has been establishing world wide network between innovative manufacturer and supplier for future human life.
Doi offers wide ranges of undergrounding material and solution. And we can propose total solutions including Designs and technological services for our client not only product proposal.
Manholes, Cable Boxes
Wide range of sizes, specifications, materials,,, we can produce and propose handholes made from concrete and recycled composite material due to client demand and construction site condition & situations.
Manhole Covers
Doi offers various manhole covers made from casting iron and recycled composite materials. We are also possible to design as requested.
Pipes & Couplings
Our pipes and connectors secure power cable and telecom network for human society. We offer product solutions and maintenance support for cable network.
Water sealing
Wide range of water sealing demand in all over the world,,, we provide best material and proposal against water leaking.
Seismic Isolation Engineering
For our safety and sophisticated human life, we have been promoting our cable supporting system over years.
Utility Pole Elimination project referenced products & services
As a most experienced and innovative cordinator for this project, we offer total solutions and products for civil engineering in Japan. We have been promoting Smart and Compact city establishing movement in the world.
Security systems with renewable energy
We offer ecological & safety energy systems and many kind of networking system for our society.
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