What O&K Company does

O&K Company Limited is a privately held Japanese manufacturer of cold heading steel wire, founded in January 1925 by Kaneo Oku in Osaka and led today by President Kazuta Oku (since 2008), with his father Takao Oku serving as Board Chairman and CEO. The company produces precision steel wire for cold heading and cold forging of fasteners (screws, bolts, nuts) and other components, with a diameter range of 0.6mm to 40.0mm, via an integrated three-process system: spheroidizing annealing, acid pickling with zinc phosphate coating, and wire drawing using ECPS (Eddy Current Partial Shaving) defect detection. Operations span 9 locations: four domestic sites in Japan (Osaka HQ and plant, Nagoya plant adjacent to Nagoya Port, Gunma plant, and the Higashiosaka registered headquarters with R&D and training), and overseas operations including O&K American Corp. (Chicago and Seymour, Indiana plants, both IATF 16949 certified), the Kobe CH Wire (Thailand) joint venture (25% stake since 2002), and a Mexico joint venture established in 2014. Group headcount is approximately 700 (286 in Japan), annual wire drawing volume is approximately 280,000 km (equivalent to ~7 times around the Earth), and roughly 5,000 SKUs are handled domestically across 34 prefectures with exports to 8 countries.

The business model is B2B direct sales to parts manufacturers in four primary verticals: automotive (primary), construction machinery, home appliances, and building/construction. Go-to-market combines regional sales departments (Kansai, Chubu, Kanto) with online ORDER JP and ORDER EN ordering portals and a door-to-door container delivery system enabled by AEO Authorized Exporter certification (industry-first, 2007). O&K holds IATF 16949:2016 (automotive quality management, since 2004), ISO 14001 (environmental, since 2000), ISO 9001, and historically ISO/IEC 17025 laboratory accreditation (voluntarily discontinued May 2025). Customers value the company's dimensional accuracy, low material loss, traceability, and certifications required for automotive supply chains. Subsidiaries include O&K Sales, Inc. (1974), O&K American Corp. (1980, wholly-owned), Kobe CH Wire (Thailand) Co., Ltd. (1997, joint venture), and OKUKANE Corporation (2002, technical development). Stated capital is ¥50 million; revenue is not publicly disclosed.

Name

O&K Company

Legal name

株式会社オーアンドケー

Website

https://oandk-co.com

Company type

Private

Founded year

1925

Operating status

Operating

Headcount range

51–100 employees

Short description

O&K Company is a 100-year-old Japanese manufacturer of cold heading steel wire (0.6mm–40mm diameter) serving automotive, construction machinery, home appliance, and construction parts manufacturers via plants in Japan, the US, Thailand, and Mexico.

Ownership category

akta.pro rank

Headquarters

HQ city

Osaka

HQ country

Japan

HQ region

Asia

Offices7 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Supply Chain, Operations, Personnel, Infrastructure, Technology or R&D, Marketing or Sales

Revenue model

1. Cold Heading Steel Wire Manufacturing and Sales: Core business of manufacturing and selling cold heading steel wire (冷間圧造用鋼線) for domestic and international markets. Wire is used as material for screws, bolts, nuts, and other precision parts. Revenue generated through direct sales to parts manufacturers in automotive, construction machinery, home appliances, and construction sectors.
2. Export Sales: International sales of cold heading steel wire to customers in USA, Thailand, and other countries. Exports conducted through Osaka and Gunma plants with container shipping. The company holds AEO (Authorized Exporter) certification for streamlined customs clearance.

Pricing tiers

Go-to-market motion2 records

Distribution channels4 records

Marketing channels4 records

Core offering

O&K Company manufactures and sells cold heading steel wire (冷間圧造用ワイヤー) for domestic and international markets. The wire is produced through a proprietary three-stage process of annealing, acid pickling, and wire drawing, yielding diameters from 0.6mm to 40.0mm for use as raw material for screws, bolts, nuts, and other precision cold-forged parts in the automotive, construction machinery, home appliance, and building/construction industries.

Product overview

O&K Company is a specialized manufacturer of cold heading steel wire for precision industrial parts. The company operates a unified product portfolio centered on cold heading steel wire, supported by three core manufacturing processes: annealing (heat treatment), acid pickling (surface treatment), and wire drawing. These processes work together to produce wire with specific strength and diameter tailored to customer needs, used primarily in automotive fasteners (bolts, nuts, screws), construction machinery, and robotics components.

Differentiator

Problem solved

Functional benefit

Products and services

• Cold Heading Steel Wire (冷間圧造用ワイヤー) Specialized steel wire processed at room temperature for manufacturing precision parts such as bolts, nuts, and screws. Features low material loss and high strength, serving automotive, construction machinery, home appliance, and robotics applications. Diameter range 0.6mm to 40.0mm with approximately 5,000 SKUs produced annually.

Quantifiable outcome

• Low material loss and high strength wire resulting in cost efficiency for parts manufacturers
• +2 more outcomes

Named customers4 records

Segments4 records

Ideal customer profiles4 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature6 records

Partnerships

Four partnerships are on record, tiered minor and core.

• Gunma Crane ThundersminorGTM or Marketing Partner · 1 October 2023Official partner contract with B.League professional basketball team Gunma Crane Thunders based in Ota City, Gunma Prefecture. Local community support and sports team sponsorship demonstrating commitment to regional development.
• Kobe CH Wire (Thailand) Co., Ltd.coreStrategic or Co-development Partner · 1 January 1997Joint venture company established in Thailand for local production and supply of cold heading wire materials. Initial capital participation 11% (1997), increased to 25% through share acquisition in 2002. Serves Southeast Asian automotive production hub from Bangkok location, operating for over 20 years.
• 伊藤忠商事株式会社 (ITOCHU Corporation)minorChannel Partner/ Reseller/ Distributor · 1 January 1981ITOCHU Corporation sold 52% shares of Settsu Tessenn Co., Ltd. to O&K in 1981, allowing O&K to enter management and subsequently operate the company as O&K Steel Co., Ltd. (merged in 2010). Historical distribution partnership through major trading company.
• O&K American Corp. (USA Operations)coreStrategic or Co-development Partner · 1 January 1980Wholly-owned subsidiary established in Illinois, USA in 1980 for market research and streamlined export operations. Expanded with Wire Sales Company acquisition in 1985. Second plant established in Seymour, Indiana in 2010. Chicago and Seymour plants serve North American cold heading market with ISO 9001 and IATF 16949 certifications.

Scale indicators8 records

Recent moves19 records

Expansion highlights6 records

Direct peers

• NETUREN Co., Ltd. Japanese specialty steel and heat treatment company producing wire products and induction heating equipment for fastener and automotive applications. Comparable Japanese peer with cold heading wire and process technology capabilities.
• Daido Steel Co., Ltd. Japanese specialty steel manufacturer producing high-grade steel wire and bar products for automotive and industrial fastener applications. Comparable as a domestic Japanese peer serving overlapping cold heading and fastener end-markets.
• Aichi Steel Corporation: Japanese specialty steel producer with significant cold heading wire and stainless steel wire products serving automotive fastener manufacturers. Direct comparable in product mix and customer base within Japan.
• Bekaert SA: Belgian-based global leader in steel wire transformation and coating technologies serving automotive, construction, and industrial markets. Highly comparable as a specialty steel wire producer serving fastener and cold heading applications across multiple continents.
• Tree Island Steel Ltd. Canadian-headquartered manufacturer of steel wire and wire products serving construction, industrial, and agricultural markets. Comparable as a mid-sized specialty steel wire producer with North American manufacturing presence.
• Kobe Steel, Ltd. (Kobelco): Japanese integrated steelmaker with wire products business and explicit partner through Kobe CH Wire (Thailand) JV (since 1997). Direct comparability in steel wire manufacturing serving automotive fastener supply chains in Asia.
• Suzuki Garphyttan AB: Swedish specialty manufacturer of cold heading steel wire (formerly Suzuki Metal), serving fastener manufacturers globally with a comparable niche focus on precision steel wire for cold forming applications.
• Insteel Industries Inc. US-based manufacturer of steel wire products including welded wire reinforcement and prestressed concrete strand. Comparable as a North American specialty steel wire producer serving construction and industrial customers.

Broad incumbents

• Voestalpine AG: Austrian integrated steel and technology group producing specialty wire rod including cold heading grades for fastener manufacturers. Comparable product overlap but operates as a diversified steel and automotive components incumbent.
• Nippon Steel Corporation: Largest Japanese steelmaker offering a broad product portfolio including steel wire rod for cold heading applications. Comparable at the product level but operates as a diversified incumbent rather than a cold-heading-wire specialist.

Market position

Strengths4 records

Weaknesses5 records

Competitive moat7 records

Key risks6 records

Key highlights7 records

Customer concentration

Compliance5 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Subsidiaries4 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about O&K Company