October 1990

            Robert G. Davenport incorporated Cornerstone Valve in Spring, Texas, USA.  Davenport started Cornerstone after 15 years of design and manufacturing experience in the severe service ball valve industry.

June 1991

            Cornerstone Valve acquired its first manufacturing facility on Klein Cemetery Road in Spring Texas, where its headquarters remained until 1996.  Early during this time period, Cornerstone underwent API audits and became qualified to manufacture valves under API 6A and 6D licenses.

July 1996

            Due to an increase in production, Cornerstone relocated to a larger facility in Tomball, Texas.  To meet these demands, personnel were added in the areas of engineering and production.  At this time, Cornerstone expanded its product line to include high pressure check and rotary control valves.

October 1997

            Cornerstone Valve Inc. was purchased by Hunt Valve Company of Salem, Ohio.  Hunt was a specialty valve company servicing the metal processing industry and U.S. Navy customers.  Hunt moved Cornerstone to a larger facility on the northwest side of Houston at Beltway 8 and Hwy 249.  Cornerstone increased its customer base addressing their severe service challenges and applications.

November 1999

            In 1999 the Cornerstone Division was acquired by YCV Corporation of Phoenix, Arizona, a wholly owned subsidiary of Yamatake Corporation of Tokyo, Japan.  It was during this time period, in addition to its API 6A and 6D qualifications, Cornerstone became ISO 9001 certified.  In the spring of 2002 YCV changed its name to Yamatake America Inc. and late in 2003 the company moved to a larger facility to accommodate the growth of the Cornerstone Valve Division.

July 2004

            Principal Robert G. Davenport and a group of investors purchased the Cornerstone Valve division.  Cornerstone Valve USA, LP was formed and operates at its Cutten Road location in Houston, Texas, USA.  Cornerstone produces severe service Ball, Check, and Rotary Control Valves in accordance with ISO 9001 standards and under API 6A PSL1-4 and 6D licenses.  Cornerstone continues to satisfy its customers and end users by producing “VALVES THAT WORK.”