317® T-ONE-S | Our Story and Milestones

It started with one engineer's conviction

Founded in Taiwan in 1968 by Chairman Teng-Chien Wu, the company has operated as T-ONE-S (MFG) TRADING INC. since 1979. 317® has been our core brand from the very beginning. 

With a background in mechanical engineering, Mr. Wu recognized early on the importance of industrial safety and precise flow control in plant operations. He led the team in product design and manufacturing, developing a range of piping components and industrial valves for air, water, oil, vacuum, gas, and steam, across a variety of materials and specifications.  That engineering foundation remains at the heart of 317® today.

To provide more complete flow control solutions, Mr. Wu expanded our product range and supply capacity through long-term partnerships:

1988  PRO UNI-D CO., LTD. was established, beginning a close and long-term working relationship with T-ONE-S. From the outset, the two companies have supported one another in marketing, distribution, and sales. PRO UNI-D specializes in the development and manufacture of 2/2-way solenoid valves and electric valves, and holds multiple patents. Its products carry UL, CE, and CSA certifications, and its quality management system is certified to ISO 9001.

1989  SINO THAI METAL CASTING CO., LTD. was established in Thailand through investment. The company manufactures stainless steel pipe fittings and valves in accordance with applicable product specifications and standards, further strengthening our overseas manufacturing and supply capacity.

Quality Built over Decades

For more than half a century, T-ONE-S has served the steam piping, boiler component, and industrial valve sectors. Quality, safety, and reliability remain central to how we work.

1999 T-ONE-S obtained ISO 9001 Quality Management System certification, establishing systematic quality management and control processes.

2020 The 317® Safety Valve Series received CE certification in accordance with EN ISO 4126-1:2013 and completed conformity assessment under the Pressure Equipment Directive (PED) 2014/68/EU, Module B + D.

Products and Markets

Built on decades of valve manufacturing experience, T-ONE-S manufactures 317® Safety Valves in-house. Together with PRO UNI-D, SINO THAI, and other long-term partners, we also supply steam traps, solenoid valves, electric valves, and a broad range of industrial valves, piping components, and boiler accessories.

• Core valves: Safety Valves, Steam Traps, Solenoid Valves, Electric Valves, Ball Valves, Gate Valves, Knife Gate Valves, Globe Valves, Check Valves, Butterfly Valves, Ball Float Valves, Needle Valves, Pressure Reducing Valves, and Control Valves.

• Piping components: Steam and industrial piping components, and boiler-related accessories.

Based in Taiwan, we serve customers across the Middle East, Africa, the Americas, Europe, and Southeast Asia. Over the years, we have built long-term relationships with distributors and business partners worldwide.

Let's talk about what you need

For more than fifty years, engineering expertise and quality have remained at the heart of what we do. The trust of our customers and the long-term relationships we have built with our partners continue to drive us forward. Whether it's product selection, specification review, or a quotation, we're happy to hear from you.

317® — Reliable Pressure & Flow Control Solutions Since 1968 
317® Safety Valves · Made in Taiwan 
T-ONE-S (MFG) TRADING INC.