The Evolution of the Legendary Asahi/America Type-21 Ball Valve

It only takes a quarter turn of the handle to understand the quality of an Asahi/America Type-21 ball valve because of the smooth and consistent turn of the handle. Our valves are designed for various applications including chemical service, so we take extra steps during our production to ensure that the highest quality product is created.

We invite you to learn more about our valves. If you would like to register to receive a 1” PVC ball valve so you can experience the quarter-turn challenge, sign up here.

Before our current ball valve model, we pioneered various markets with our Duo-Bloc ball valve model, which was among the first true industrial thermoplastic valve. I visited and toured multiple facilities and am no longer surprised to see our Duo-Bloc still performing well 30 years after installation.

Expanding on the success of the Duo-Bloc, Asahi introduced the Type-21 in 2003 as a major industry improvement for the growing application range focused on quality and reliability. The valve design incorporated double o-ring stem seals, which ensured the operator and facility remained safe even if the handle experienced failure from over torqueing. This could happen if something was caught in the line and the operator continued to force, either manually or with an actuator, the valve shut.

Other improvements made to the Type-21 include single-side adjustable carriers instead of two. This allows for a consistent centering of the ball within the body and helps improve field safety when used as a blocking valve to eliminate a carrier with a threaded connection. You may even notice the molded flow indicator, which indicates how to install for safe blocking operations.

Inside the valve, the PTFE seat design includes backing cushions that preload the seat to compensate for wear over time. This innovative design prolongs maintenance cycles significantly. A spanner wrench for the carrier is molded into the handle to allow for easy onsite adjustments when valve maintenance is required.

Another customer request, which was included in the design updates, was a ISO-5211 mounting pad underneath the handle for easier actuation adaptation in the field. We also included provisions for a panel mount on the bottom of the valve to easily mount to flat surfaces and help secure the valve in place.

Asahi/America introduced the Type-21a (or alpha) in 2010 with sizes through 2”, which included an improved PTFE seat design that further extends maintenance cycles and tapered o-ring grooves on the end connector face seals to help hold the o-ring in place when removing the end connectors. The body mold was improved to include flats on either side so a wrench could be used to prevent the valve from rotating during tightening of the union nut.

In a truly innovative design, the carrier was changed to a left-hand thread, or reverse thread, so accidental over torqueing of the ball during installation in the field would be impossible. Because Asahi understands our customers’ applications, we take product changes extremely seriously. Asahi/America’s R&D lab in the US and Asahi Yukizai’s R&D lab in Japan are dedicated to creating designs that will far exceed any available standards. We utilize our own set of testing requirements, including burst pressure testing of the body, sealing performance testing, and cycle testing more than 5,000 times, in accordance with ISO 16135 through ISO 16138 requirements. Asahi/America’s innovations also expands into our warranties as we became the first manufacturer to offer an industry leading three-year warranty for our valves and factory-assembled actuated valve packages in 2019.

For almost 50 years, Asahi/America has lived up to our motto, “Your Experts in Plastics,” and have been at the forefront of thermoplastic pipe, valve, actuation, fittings, fusion tools, manufacturing, and development industry. Give us a call and we will be glad to share our expertise with you!

EDITOR’S NOTICE: Please note, the information in this article is for educational purposes only and does not supersede any Asahi/America technical information or product specifications. Please consult Asahi/America’s technical department at 1-800-343-3618 or [email protected] on all product applications in regards to material selection based on the pressure, temperature, environmental factors, chemical, media, application, and more.