Yoshiwa Kogyo

What Yoshiwa Kogyo does

Yoshiwa Kogyo Co., Ltd. (ヨシワ工業株式会社) is a privately held Japanese foundry and machining company founded in 1937 and headquartered in Kaita, Hiroshima Prefecture. It manufactures cast iron automotive components—disc plates, differential gear cases, flywheels, front knuckles, calipers, brake drums, torque members, and related parts—using gray cast iron (FC) and ductile cast iron (FCD) in green sand molding processes. The company operates an integrated production system spanning casting, machining, painting, production planning, and shipping across three production bases: the Head Office/Kaita Plant in Hiroshima, and the Muikaichi and Hatsumi Plants in Yoshika Town, Shimane Prefecture. Core technology includes automatic molding lines (DISA-MK5, KDH, ACE-5, FBM-3L), medium-frequency induction furnaces, cupola furnaces, spectrometer-based chemical composition control, robotic core setting, and 100% automated inspection systems. The company produces approximately 300,000 disc plates per month, ranking top-class in West Japan.

The business model is B2B sale of cast iron components to automotive OEMs and Tier-1 suppliers, with Mazda Motor Corporation as the anchor customer since 1977—including a 1981 equity capital investment from Mazda and a 100% Mazda vehicle fitment rate for disc plates. Other major customers include AS Brake Systems, Kawada Corporation (Kawada Seisakusho), Kubota Iron Works, Hiroshima Seimitsu Kogyo, and Advics. Reported net sales have ranged from approximately ¥10.4B to ¥15.1B across recent fiscal years, with FY63 (April 2025–March 2026) at ¥13,761M. Pricing is contract-based and not publicly disclosed. The company operates exclusively in the domestic Japanese market, with limited cross-border footprint beyond a 1989 capital/technical partnership with South Korea's Ajoo Metal Co., Ltd. Revenue derives entirely from hardware sales of cast iron components.

Yoshiwa holds IATF 16949 (2018), ISO 14001 (2002), and prior ISO 9002/QS-9000 certifications, and has committed to a 50% CO2 reduction by 2030 (vs. FY2013) and carbon neutrality by 2050. In 2024 the company received the Mazda Supplier Excellence Award for co-creation activities and carbon neutrality efforts, alongside multiple Japan Foundry Society and kaizen awards. The company maintains a stable workforce of approximately 400–425 employees with average tenure of 15.6 years, supported by the proprietary Yoshiwa Mirai School (ヨシワ未来塾) training program. Most recent strategic repositioning includes the establishment of a new Cost Planning Section (2025) to institutionalize cost competitiveness amid automotive pricing pressure.

Name

Yoshiwa Kogyo

Legal name

YOSHIWA KOGYO Co., Ltd.

Website

https://yoshiwa.co.jp

Company type

Private

Founded year

1937

Operating status

Operating

Headcount range

251–500 employees

Short description

Yoshiwa Kogyo is a 1937-founded Japanese foundry manufacturing cast iron automotive components—disc plates, differential cases, flywheels, knuckles, and brake parts—primarily for Mazda Motor Corporation and Japanese Tier-1 suppliers, operating three integrated production bases in Hiroshima and Shimane.

Ownership category

akta.pro rank

Product category

Automotive Cast Iron Components

NAICS

Motor Vehicle Parts Manufacturing (3363), Motor Vehicle Steering and Suspension Components (except Spring) Manufacturing (336330)

SIC

Metal Forgings & Stampings (3460)

akta.pro primary industry

Truck Chassis, Axle, Suspension & Brake Systems Manufacturing (IMACABAL)

akta.pro secondary industry

Steering Systems & Components (Columns/Racks/EPS Pumps & Motors) (IMACAIAB)

Keywords

• Cast iron automotive parts
• Automotive brake components
• Iron foundry manufacturing
• Automotive OEM supplier
• Disc plate casting

Headquarters

HQ city

Hiroshima

HQ country

Japan

HQ region

Asia

Offices5 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

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

Revenue model

1. Automotive Cast Iron Parts Manufacturing and Sales: Manufacture and sale of cast iron automotive components including disc plates, differential gear cases, brackets, calipers, torque members, pairing inserts, knuckles, and flywheels. The company operates an integrated production system from casting to machining. Revenue has ranged from approximately 13.8 billion yen to 15.1 billion yen across recent fiscal periods (FY59-63).

Go-to-market motion2 records

Distribution channels2 records

Marketing channels6 records

Core offering

Yoshiwa Kogyo manufactures cast iron automotive components—including disc plates, differential gear cases, flywheels, knuckles, calipers, torque members, and brake drums—using an integrated in-house production system spanning casting, machining, painting, production planning, and shipping. The company specializes in gray cast iron (FC) and ductile cast iron (FCD) for safety-critical brake, drivetrain, engine, and chassis applications, supplying directly to Mazda and Tier-1 automotive suppliers in Japan.

Product overview

Yoshiwa Kogyo is a cast iron automotive parts manufacturer offering a unified product portfolio centered on casting and machining of automotive components. The core products include disc plates, differential cases, flywheels, front knuckles, calipers, torque members, and brake drums—all serving critical safety and drivetrain functions in vehicles. The company operates an integrated production system spanning casting, machining, painting, and shipping, with production facilities in Hiroshima (Kaita Plant) and Shimane Prefecture (Muikaichi and Hatsumi Plants). The company specializes in gray cast iron (FC) and ductile cast iron (FCD) components, with disk plate production at approximately 300,000 units per month, achieving top-class production volume in Western Japan.

Differentiator

Problem solved

Functional benefit

Products and services

• Disc Plate (Brake Component)
• Differential Gear Case (Drivetrain)
• Flywheel (Engine Component)
• Front Knuckle (Chassis)
• Caliper (Brake Component)
• Torque Member (Brake Component)
• Brake Drum (Brake Component)

Quantifiable outcome

• 100% Mazda vehicle fitment rate for disc plates
• +3 more outcomes

Named customers6 records

Segments1 record

Ideal customer profiles2 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature7 records

Partnerships

One partnership is on record.

• Various Suppliers (サプライチェーン)coreOthers · 7 January 2025Yoshiwa Kogyo registered its 'Declaration of Partnership Building' (パートナーシップ構築宣言) in January 2025, committing to strengthen partnerships across the supply chain. This includes supporting partners with telework implementation, BCP planning, and carbon neutrality efforts. The company also adheres to fair trade practices including fair pricing, proper tooling cost management, cash payments where possible, and respecting supplier IP rights.

Scale indicators10 records

Recent moves11 records

Expansion highlights5 records

Broad incumbents

• Brembo S.p.A. Global leader in high-performance brake systems and disc manufacturing. Comparable as a brake disc supplier, though serving premium and global OEM customers with broader geographic and product reach than Yoshiwa.
• Aisin Corporation: Major Japanese Tier-1 automotive parts supplier including brake and chassis systems, with far broader product portfolio. Competes with Yoshiwa as a supplier to Japanese OEMs (including indirectly to Mazda's supply chain) but at much greater scale and product breadth.
• Advics Co., Ltd. Toyota-affiliated brake system manufacturer and one of Yoshiwa's listed customers. Relevant as a major brake-system integrator sourcing cast iron brake components from foundries like Yoshiwa, representing both a customer relationship and an adjacent competitive vertical.
• Proterial, Ltd. (formerly Hitachi Metals): Large Japanese manufacturer of specialty metals and automotive cast and forged components, including brake and drivetrain parts. Comparable in automotive iron casting, though at vastly greater scale and broader portfolio.

Direct peers

• Topy Industries, Ltd. Japanese manufacturer of automotive steel wheels and cast components, with significant cast iron and forged parts supply to Japanese OEMs. Comparable on automotive castings and Japanese OEM customer profile.
• Chuo Malleable Iron Co., Ltd. Japanese manufacturer of cast iron and malleable cast iron components serving automotive and industrial markets, with a comparable focus on safety-critical cast parts for Japanese OEMs. Closest direct competitor in cast iron automotive components.
• Howa Machinery, Ltd. Japanese automotive parts and machine tool manufacturer producing cast and machined components. Overlaps with Yoshiwa on cast iron automotive components and machining capability, with a similar mid-cap Japanese profile.
• Sintokogio, Ltd. Japanese foundry equipment and castings producer serving automotive and industrial customers. Comparable in casting technology and Japanese OEM customer base, though Sintokogio also supplies foundry equipment globally.

Emerging players

• Ashinaga Industry Co., Ltd. (Ashina): Japanese mid-cap automotive parts and cast iron manufacturer serving Japanese OEM supply chains. Comparable size and customer profile to Yoshiwa, with similar casting-and-machining capability for automotive components.

Regional players

• Ajoo Metal Co., Ltd. South Korean foundry and cast iron parts manufacturer with which Yoshiwa entered a capital and technical partnership in 1989. Comparable in cast iron component production for automotive applications, but focused on the Korean OEM market rather than Japanese.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights7 records

Customer concentration

Compliance4 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles7 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 Yoshiwa Kogyo