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Siam Toyota manufacturing announces regular organizational changes for January 2021

Word Press Release (EN)
Word Press Release (EN)
Excel Profile of New Presi...
Excel Profile of New President EN

        Today, Siam Toyota Manufacturing (STM) announced its regular organizational changes effective 1 January 2021, as it continues to work to even further enhance its competitiveness as Toyota’s key engine production hub. As part of the changes, STM is going to welcome a new president, effective 1 January 2021. 

        Successfully completing his five-year assignment as the president of STM, Yuji Hiraoka is going to move to Toyota Motor North America. Hiraoka has led STM’s journey to further enhance the company’s competitiveness. The efforts which he has made include a number of activities to help embed the Toyota Production System, the company’s management philosophy for maximizing efficiency through the elimination of inefficiency, and ensure that it is applied and deployed not only to production but also across functions in STM. Through these efforts, STM has enhanced its productivity and quality of its products.

        Virayot Prutakorawong, vice president in charge of administration of STM, will succeed Hiraoka as the president of STM. Since joining STM in 1992, Virayot has accumulated his expertise in multiple areas such as manufacturing engineering. One of his accomplishments is that he successfully led the project for starting the production of the new GD engines at STM. He has also had experiences in non-STM organizations, such as at Toyota Motor Corporation in Japan and Toyota Daihatsu Engineering & Manufacturing, Toyota’s regional office for Asia, which helped him develop a broader viewpoint to manage STM well. The presidency change marks the first appointment of a Thai local talent to the post of STM president, as part of Toyota’s efforts to appoint the right person for the right job.

        As he completes his term as the STM president, Hiraoka said, “I very much appreciate all the tremendous support from our stakeholders, not only to myself, but also to Siam Toyota Manufacturing at large. I truly enjoyed my work and life in the Land of Smiles, and I am sure I will miss it. The productivity, quality and kaizen mind of the team here is second to none. I request everybody’s continued support to Mr. Virayot and to the STM family.”

        Having been appointed to the role of president of STM, Virayot commented, “I am honored to have been given the opportunity to lead STM as its president, and am determined to do everything possible for strengthening the company’s competiveness and position as the most important hub for engine production in the Toyota Group. As a Thai local citizen, I am passionate to contribute to STM in its continued journey to further enhance its self reliance and become even more rooted in Thailand as a good corporate citizen.”

Mr.Virayot   Prutakorawong

นาย  วิรยศ   พฤทธากรวงศ์


Siam Toyota Manufacturing Co.,Ltd.

Personal Data

Date of Birth 17-02-1971 (  Now 49 years old)

Home Country Bangkok, Thailand


Faculty of  Engineering (ME), King Mongkut's Institute of Technology Ladkrabang (KMIT'L).


1992   Joined Siam Toyota Manufacturing Co.,Ltd. (STM) , Engineer of Engineering Divison.

1993   Training at Toyota Motor Corporation

1994   Engineer of Maintenance & New Project Department , STM

1998   Assistance Manager of Manufacturing Engineering Division , STM Plant Relocation Project (Ladkraband → Amatanakorn)

2001   Department Manager of  Manufacturing Engineering Division , STM IMV Project Preparation (KD Engine)

2008   Deputy General Manager of Manufacturing Engineering Division , New Project Group (Engine Plant no.2 Preparation) , STM and support Overseas Affiliates. (Unit Koryukai)

2011   Deputy General Manager of Diesel Engine Manufacturing Division , STM

2013   Deputy General Manager of New Project Group (GD Engine) , STM

2014   General Manager of New Project Group (GD Engine) , STM

2015   General Manager of Engine Plant No.3 Division (GD Engine) , STM

2016   General Manager of 3 Pillars Division , STM and support Overseas Affiliates.

Jan, 2018   Project Vice President of Production Control Department (Overseas Affiliates Productivity Improvement) , Toyota Daihatsu Engineering & Manufacturing Co., Ltd.

Jan, 2020   Vice President of Administration Group , Siam Toyota Manufacturing Co.,Ltd.

Jan, 2021   President , Siam Toyota Manufacturing Co.,Ltd.