• PRODUCTION SYSTEM In-house integrated production system - consistent manufacturing with meticulous attention to detail.

Production Network for Yanmar Marine Commercial Engines

Yanmar is one of only a few engine manufacturers to have implemented an integrated production system. At our Amagasaki and Tsukaguchi factories, we carry out each stage of engine production, from machining and assembly, through to outfitting, testing, and shipment. The factories are mechanized to promote automation and labor saving, and we have established an order entry system adapted to our product’s characteristics and which allows us to manage the progress and history of each individual engine. With this system, we manufacture products of the highest quality. Furthermore, Amagasaki and Tsukaguchi take delivery of components manufactured at other Yanmar Group factories, such as cylinder blocks, fuel injection systems, gears, and clutches, meaning that our engines are produced almost entirely in-house.

Amagasaki factory

Automation and thorough quality control for absolute peace of mind

The Amagasaki factory opened in 1936, manufacturing the world’s first commercially viable small diesel engine. In time, the factory started mass-producing propulsion and auxiliary engines for marine vessels, and diesel engines for land-use and general applications. The factory also started producing gas turbines in 1983. Combining the in-situ “cell production method” together with line production, the factory also promotes automation and labor saving with the use of our own high-performance specialist equipment and state-of-the-art facilities. By establishing a traceability and quality control system, we can produce products of outstanding quality.

Advanced production system which has received global recognition

In July 1992, we obtained ISO 9001 certification from Lloyd’s Register (LRQA). Then in June 1997, responding quickly to changing environmental issues, we became the first manufacturer of large land/marine-use diesel engines to obtain ISO 14001 certification. We were also the first engine manufacturer in Japan to obtain ClassNK (Nippon Kaiji Kyokai) certification in respect of IMO emissions regulations for NOx (Tier 1 in 2000, and Tier 2 in 2011). The leading-edge technologies developed by us to reduce environmental impact are recognized internationally.

ISO 9001(International Organization for Standardization)

Quality Management Systems Certification No:

ISO 14001(International Organization for Standardization)

Environmental Management Systems Certification No:

Certified under voluntary inspection by 10 shipping classification societies

Our Amagasaki factory is certified by 10 of the world’s largest shipping classification societies,
and is the world’s first factory to be certified under voluntary inspection by 10 societies.

  • Nippon Kaiji Kyokai (NK) - Japan
  • American Bureau of Shipping (ABS) - US
  • Lloyd’s Register (LR) - UK
  • Registro Italiano Navale (RINA) - Italy
  • Bureau Veritas (BV) - France
  • Korean Register (KR) - South Korea
  • China Classification Society (CCS) - China
  • Indian Register of Shipping (IRS) - India
  • Russian Maritime Register of Shipping (RS) - Russia

Integrated production system for high-performance engines

Production Processes for Diesel and Gas Engines


During the machining process, key components of the engine such as the cylinder block, cylinder liner, crankshaft, camshaft, and connecting rods etc. are all machined with high precision and efficiency.


After machining, each part is properly assembled with the correct torque and sequence as instructed by our work navigation system.


The assembled engines are placed on a base plate and additional equipment such as generators, pumps, compressors, and clutches are installed, together with any necessary piping.The engines can also be fitted with an electro-hydraulic system, for automated and remote operations, according to the customer’s specifications.


After outfitting, each engine is rigorously tested by a qualified engineer, run under conditions equivalent to actual operating conditions on-board a vessel. Further inspections are simultaneously conducted to determine compliance with the Ship Safety Act and the standards of the Fisheries Agency of Japan and also members of International Association of Classification Society(IACS).


The engine is coated, treated to prevent rusting, inspected for shipping and then packaged for shipment to a location either within Japan or overseas.

Gas turbine Production

Parts such as the impeller, rotor, and nozzle are finished with ultra precision by the 5-axle control machine or the NC dedicated device, with the turbines assembled in a highly-controlled process. The turbines are then fitted with various generators and accessories and are shipped out after undergoing stringent testing and inspections.

Machining (impeller machining)

Assembling (clean room)



Quality control with traceability

During the machining process, a QR code is printed onto each part using a laser. In this way, all data generated during each stage of production is recorded. By conducting statistical and mathematical analysis using this recorded data, we work to achieve even higher levels of performance and quality.

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