DAI-ICHI HIGH Frequency Co., Ltd.

DAI-ICHI HIGH Frequency Co., Ltd. (DHF) is a Japanese engineering company headquartered in Tokyo that has built its business around high-frequency induction heating (IH) technology since its founding in 1950. The company describes itself as continuing to pursue "manufacturing sought by the world" as its corporate style, and its philosophy is expressed as "independence in management, proprietary technology, and respect for people." DHF's operations are organized into six main domains: pipes, surface treatment, machinery, rebar, bimet (bimetal composite products), and plant engineering. In the pipe business, DHF manufactures and sells high-frequency induction-heated bending pipes, polyethylene powder-lined pipes and other piping materials, and also provides piping prefabrication design and fabrication. Its surface treatment business applies induction heating to heat treatment of products such as rolls for the steel and resin industries, high-frequency hardening, laser heat treatment and maintenance services. The machinery business designs and builds equipment and systems, develops induction-heating tools for plant maintenance, and offers commissioned testing and development. In rebar, DHF supplies T-head method rebar, a mechanical anchorage system developed jointly with Shimizu Corporation in which the rebar end is hot-formed into a T-shape by high-frequency induction heating. Its bimet products, marketed under the DHF Bimet brand, include BT&P (bimetal boiler tube and panel) and DML (bimetal steel pipe), combining self-fluxing alloy technology with IH processing. Plant engineering covers detailed and production piping design using 3D/2D CAD. DHF serves a wide range of industries, including industrial plants, steelmaking plants, power plants, environmental plants, petrochemical plants, electronics plants, public civil infrastructure, shipbuilding, non-ferrous metals, rolling stock and machinery. The company maintains a nationwide network of offices and factories in Japan and has pursued global expansion. Recent public notices on its website include a world-first demonstration test using seawater-derived magnesium, the launch of a "DHF Y-joint" product page, a warning about spoofed emails impersonating a company director, and the establishment of DHF World Rich G Japan (DWS).

DAI-ICHI HIGH Frequency Co., Ltd. (DHF) traces its origins to 1950, when the company was founded in Japan. From the beginning, its business has centered on the application of high-frequency induction heating technology, a field in which it has accumulated decades of engineering expertise. The company's official history page notes that it has walked together with induction heating since its founding in 1950. Over the decades, DHF expanded its technology into multiple business domains. In pipes, it developed high-frequency induction-heated bending and polyethylene-lined pipes, and later added piping prefabrication and water transport applications. In surface treatment, it applied induction heating to heat treatment, including high-frequency hardening of gears and rolls, and later added laser heat treatment and maintenance services. In machinery, it leveraged its induction heating know-how to design and manufacture equipment and systems, including plant maintenance tools. A notable proprietary technology is the T-head method rebar, developed jointly with Shimizu Corporation. This method uses high-frequency induction heating to hot-form the rebar end into a T-shape, creating a mechanical anchorage that replaces conventional standard hooks in reinforced concrete structures. DHF supplies T-head rebar for both building and civil engineering structures, processing rebar from various manufacturers according to specifications. Another distinctive technology is the DHF Bimet product line. These bimetal (composite metal) products are created through the synergy of the company's self-fluxing alloy technology, which provides high corrosion and wear resistance, and its high-frequency induction heating (IH) processing technology. The name "Bimet" is a coined term inspired by "bimetal." The product lineup includes DHF Bimet BT&P (bimetal boiler tube and panel) and DHF Bimet DML (bimetal steel pipe), used in municipal waste incineration plants, biomass power plants and industrial plants. DHF has also developed technologies such as rail hardening, which the company describes in its technology stories as a technique born from the "Seven Samurai" who are still talked about. Its plant engineering business provides piping basic planning through detailed design, stress analysis and on-site dispatch of SV personnel using modern 3D/2D CAD systems. In recent years, DHF has continued to announce new developments. In 2023, it exhibited at the 5th Bridge and Tunnel Technology Exhibition, highlighting high-frequency bending/square steel, T-head method rebar and the IH-type coating removal method. In 2025 and 2026, its website announced the establishment of DHF World Rich G Japan (DWS), the publication of a DHF Y-joint product page, a world-first demonstration test using seawater-derived magnesium, and a warning about spoofed emails impersonating a company director. The company also maintains a nationwide network of offices and factories in Japan and pursues global expansion.

• 2026

  Announces world-first demonstration test using seawater-derived magnesium.

• 2025

  DHF World Rich G Japan (DWS) establishment reception reported in Nikkan Sangyo Shimbun.

• 2023

  Exhibits at the 5th Bridge and Tunnel Technology Exhibition at Makuhari Messe.

• 1950

  Company founded in Japan; begins business centered on high-frequency induction heating technology.

• Develops T-head method rebar jointly with Shimizu Corporation.

• Launches DHF Bimet product line, including BT&P and DML.

Engineering company specializing in applied high-frequency induction heating technology, providing proprietary manufacturing technology and products for plants, infrastructure and industry.

• Pipe

  High-frequency induction-heated bending pipes

• Pipe

  Polyethylene-lined pipes

• Pipe

  Piping prefabrication

• Surface Treatment

  Rolls for steel and resin industries

• Surface Treatment

  High-frequency hardening (heat treatment)

• Surface Treatment

  Laser heat treatment

• Rebar

  T-head method rebar

• Bimet

  DHF Bimet BT&P (bimetal boiler tube and panel)

• Bimet

  DHF Bimet DML (bimetal steel pipe)

• Machine

  Small high-frequency melting furnace

• Machine

  Coating removal induction heating equipment

• Plant Engineering

  Plant engineering and piping design

1. 1第一高周波工業｜DHFdhf.co.jp
2. 2DHFについて｜DHFdhf.co.jp
3. 3会社紹介映像｜DHFdhf.co.jp
4. 4製品・サービス｜DHFdhf.co.jp
5. 5DAI-ICHI HIGH Frequency Co., Ltd. (Japan) - Wikidatawikidata.org