Tanoi MFG. Co., Ltd.

Tanoi MFG. Co., Ltd. (株式会社田野井製作所) is a Japanese manufacturer specializing in taps — the cutting tools used to cut internal threads (female screws) in metalworking. Founded on November 3, 1923 (Taisho 12), the company has devoted itself for over a century to a single product category, positioning the tap as the final and most critical step in metal machining, where a single defective tool can ruin an entire finished part. The company is headquartered at 953 Okaizumi, Shiraoka City, Saitama Prefecture, and operates a Saitama plant at the same address, a Miyagi plant and Tohoku sales office in Shichikashuku, Miyagi Prefecture, plus sales offices in Nagoya and Hiroshima. It serves customers nationwide in Japan and offers online consultations. Its core customers are in the automotive, precision machinery, and die-casting industries. Tanoi's product line centers on three patented 'only-one' series: the W-TF Double Toughlet rolling tap for high-hardness and difficult-to-cut materials; the SL-TF Seamless Toughlet rolling tap that addresses the flaking, contamination, and post-machining defects typical of rolling taps; and the ZC Series Zero Chip Tap, which uses a high-efficiency coolant circulation design to combine chip evacuation, cooling, long tool life, and high-speed machining. Beyond taps, the company also develops its own cutting oils, pastes, and rust-preventive agents under the Tanoi Thinkool and related brands, allowing it to propose the entire threading process as one line. A defining feature of Tanoi's business model is 'Doctor Sales' (ドクターセールス), in which sales staff are trained to act like physicians: making house calls (customer visits), taking histories (interviews), diagnosing (investigation), and prescribing treatment (improvement activities), with a dedicated attending physician for each customer. The company reports cumulative improvement cases of over 500, more than 30 industries served, an average tool-life improvement of 3.2x, and 12 patents held. The current representative director and president is Yumi Tanoi, who studied in Canada and the United States for five years after high school, joined the company, spent seven years in overseas operations, became vice president around the time of the Lehman Shock, and assumed the presidency in 2013 on the company's 90th anniversary. The company marked its 100th anniversary in 2023 and frames its mission as continuing to serve customers' threading problems for the next 100 years.

Tanoi MFG. Co., Ltd. was founded on November 3, 1923 (Taisho 12) and began manufacturing taps, the tools used to cut internal threads. From its earliest years the company concentrated on this single product category, a focus it has maintained for more than a century. In the post-war period, Tanoi introduced Japan's first rolling tap, opening a new direction in thread machining. Rolling (form) taps deform metal rather than cutting it, and this early adoption helped establish the company's reputation for technical originality. Over the decades the company built a customer base in the automotive, precision machinery, and general manufacturing sectors, positioning its taps as the 'reassurance of the final process' in production lines. It developed a portfolio of standard products — rolling taps, spiral taps, point taps, carbide taps, hand taps, pipe taps, and combination taps — while also offering custom and special-shape designs when standard products do not fit. A distinctive element of Tanoi's development was the creation of its 'Doctor Sales' approach, in which sales staff are trained to diagnose customers' threading problems like physicians. The company describes a cycle of house calls (customer visits), interviews, diagnosis, and treatment (improvement activities), with a dedicated attending physician assigned to each customer. This service model, combined with patented products, produced a body of documented improvement cases. Leadership transitioned to the third-generation president Yumi Tanoi. After graduating from high school she studied in Canada and the United States for five years, then joined the company and spent seven years in overseas operations. Around the time of the Lehman Shock she became director and vice president, and she promoted 5S activities and the 'three actuals' principle (genba, genbutsu, genjitsu — actual place, actual thing, actual reality), conducting monthly workplace environment and quality inspections. In 2013, on the company's 90th anniversary, she became representative director and president. In 2023 Tanoi marked its 100th anniversary, describing the milestone as balancing inheritance and renewal for the next 100 years. The company has continued to invest in digital transformation, publishing a DX message in March 2025 that frames digital technology as essential to solving social and customer challenges and to achieving its management vision: developing new technologies and products that contribute to society; challenging goals with creativity, vitality, and teamwork; and enriching employees' lives through business development. Its management philosophy is expressed as 'passion, sincerity, tenacity' (情熱・真心・執念). Today Tanoi operates from its headquarters and Saitama plant in Shiraoka City, Saitama Prefecture, with a Miyagi plant and Tohoku sales office in Shichikashuku, Miyagi Prefecture, and sales offices in Nagoya and Hiroshima. It serves customers nationwide in Japan and offers online consultations.

• 2026

  Notice of listing in 'Beginners Link' (August 18).

• 2025

  Publishes DX message dated March 1.

• 2023

  Celebrates 100th anniversary.

• 2013

  90th anniversary; Yumi Tanoi becomes Representative Director and President.

• 1923

  Founded on November 3 (Taisho 12); begins manufacturing taps.

• Post-war: introduces Japan's first rolling tap.

Specialist tap manufacturer offering patented 'only-one' products and 'Doctor Sales' diagnostic service, proposing the entire threading process including cutting fluids.

• W-TF Double Toughlet

  Rolling tap series for high-hardness and difficult-to-cut materials, offering longer life and high-speed machining.

• SL-TF Seamless Toughlet

  Rolling tap series addressing flaking, contamination, tightening, and post-machining defects.

• ZC Series Zero Chip Tap

  Tap with high-efficiency coolant circulation for chip evacuation, cooling, long life, and high speed.

• Tanoi Thinkool 99X Super

  High-grade cutting oil for tapping, broaching, and reaming.

1. 1株式会社田野井製作所 | タップ専門メーカー TANOItanoi-mfg.co.jp
2. 2株式会社田野井製作所 | タップ専門メーカー TANOI - 会社情報tanoi-mfg.co.jp
3. 3株式会社田野井製作所 | タップ専門メーカー TANOI - 製品情報tanoi-mfg.co.jp
4. 4Tanoi MFG. Co., Ltd. (Japan) - Wikidatawikidata.org