Cornerstone Valve Company

Cornerstone Valve, founded in 1990, is a Texas-based company located in Missouri City, Texas. Cornerstone valve has over 30 years of experience in manufacturing metal seated, zero leakage, ball, check, rotary, and severe service control valves. In addition, cornerstone Valve is Made in America and continues to produce valves in Texas.

Cornerstone Valve has a core competency of providing custom engineered, fit-for-purpose valves, and continuous development of new technology has resulted in our company’s growth and ongoing success. Cornerstone Valve line of metal seated – zero leakage products globally include the most sophisticated and unique valve installations.


Cornerstone Valve’s strategy has always focused on developing products designed to our customer’s specific requirements. By developing exclusive products, Cornerstone Valve has distinguished itself and gained prominence within this competitive industry.

Cornerstone Valve has earned a valuable reputation for fast, on-time deliveries: Cornerstone team needs to meet customer expectations for on-time deliveries. Cornerstone Valve’s mission is to support our customers and their commitments with the best solution in the shortest possible time.

With the large availability of exotic materials from reliable suppliers in the U.S.A. and G12 countries, we can manufacture a broad selection of valves in almost any material. We strive to provide our customers with whatever material they require.

Extreme Subsea Challenges

1. High Pressure – Cornerstone recommends a one-piece top-entry valve with an integral ball/trunnions stem to assure control, alignment, and maximum pipe stress resistance during installation.

2. Water Depth – Multiple sealing systems assure no leaks externally and internally.

3. Quality – Cornerstone routinely designs its valves to exceed the API 6A PSL 3 requirements. Multiple hydro tests, extended test periods, and multiple seats cycling at full-rated working pressures assure fitness for service. Cornerstone Valve will monogram valves to API6DSS standard as of 2017.

4. Reliability – Skimping on best practices in design features can result in man-eating intervention costs. In addition, subsea valves sit for long periods without being operated and exposed to saltwater, galvanic corrosion, and oil and gas with particulates.

Consequently, careful selection of valve materials is crucial. Cornerstone knows high-quality trims and seals extend the life expectancy of critical installations.

In addition, Cornerstone Valve has solutions for your most extreme
production challenges.


In an industry where reliability is a must – Cornerstone Valve was called to turn around an operation where 5200 valves were installed, and more than 4000 were inoperable!

High-temperature ranges in the industry require specific materials, such as hard-facing cobalt-based alloys. Even bolts must be carefully selected – high temperature rated or not.

Each part of our valves has a certificate verifying the chemical makeup, yield/tensile strength, heat treatment, and place of origin. Standard testing at Cornerstone Valve requires full cycling of valves under a range of pressures.

We provide complete testing documentation along with certifications. Therefore, you can rely on valves to work if they are Cornerstone.

1. Marine Environment – Frequent replacement costs are unacceptable offshore. For protection in saltwater/salt air atmospheres, valve internal sealing surfaces must be overlaid with a corrosion-resistant alloy. Cornerstone Valve can provide this feature on any of our products.

2. Weight & Space – Hub end connection valves reduce the overall weight. In addition, using non flanged connections, We offer the valves a shorter face-to-face, requiring less space.

3. Reliability – Valves installed on platforms need to be tested by API 6A PSL 3 requirements (hydro-static). Also, multiple holding times for pressure envelopes and multiple seat tests at total differential pressures applied to each seat specified. We engineer valves to exceed these rigorous standards.

4. Serviceability – Our top-entry Cornerstone Valve trunnion mounted valve design with the available in-line feature allows all
internal components to be serviced without removing the entire valve from the line – saving hours of production down-time.

  • Engineering Solutions Aerospace- In 1990, an aerospace company contacted Cornerstone Valve. They needed quick-opening valves that would shut off bubble-tight after multiple cycles: the result – a specific ball-seat interface with proprietary design developed by Cornerstone Valve.
  • Reliability – Cornerstone valves have continued to facilitate space launches ever since, performing through numerous launch cycles without servicing. The destructive marine environment of the surroundings makes this especially remarkable.
  • Quality – We meet Aerospace and NASA’s highest quality requirements.

Industry Challenges:

Cornerstone Valve has solutions for your most extreme chemical & petrochemical.

1. Safety – Emission control hazards are the top concern in this industry. The destructive media calls for live-loaded redundant sealing mechanisms with test ports for zero-emission confirmation.

2. Reliability – We at Cornerstone Valve know downtime means viscous sludge turns into a nightmare cleanup – and costly repairs. However, solid’s proofing, specific sealing mechanisms, and proper material selection equate to our valve’s long service life.

3. Durability – Cornerstone Valve engineers team up with their customers to help design valves specific to each industry need. Careful selection of materials explicit to media and process conditions accompanied by knowledgeable engineering choices mean valves that work – day in and day out.

Cornerstone Valve Cryogenic Valves

Cornerstone Valve understands Cryogenic valves help in various application areas, including natural gas processing and blowdown systems.

​These valves operate at temperatures below -50F and down to -320F and below. The shallow temperatures that the valve in Cryogenic service see require special attention to selecting materials, including metallic and non-metallic components.

Cornerstone Valve produces valves suitable for cryogenic services in a full range of pressure classes – up to API 10000. Benefits include gas and liquefied gasses. Testing is typically performed in a liquid nitrogen bath with helium as the test media.

Cornerstone Valve,  Cryogenic Valve Design Features:

  • symmetrical cross-sections to aid in uniform cooling/heating
  • accurate geometry of components (ball/seat) to assure tightness
  • live-loaded seals to ensure no gas/liquid bypass of ball & seats
  • appropriate actuation standoff to ensure operability

Cornerstone Valve has solutions for the most extreme maritime challenges:

1. Quality Control – The Navy required Cornerstone Valve to pass a Nuclear Class I Audit to qualify for the right to create its valves. The stringent testing includes shock testing, vibration testing to MIL standards, and extensive operational testing.

Cornerstone completed the typically exhausting certification program in only three months.

Cornerstone Valve Standards and Procedure Requirements

Massive amounts of detailed documentation are required – every component and the chemical makeup of every valve part must be verified and recorded. These standards come naturally to us. We recheck the product before the customer sees the final product.

Cornerstone Valve has a top entry, ball valves per API spec 6A / 6D Ball Valves Trunnion supported ball, forged body, bolted bonnet, metal to metal or soft seated sealing design, self-relieving spring-loaded seats or double piston effect sealing system, anti-static device, anti-blow-out proof stem, double block and bleed or block and bleed, vent and drain fittings, self-lubricating stem, and trunnion bearings to assure low operating torque throughout entire valve life, fire-safe design.

We have quality at every level of the organization utilizing a process approach platform. Each component within an assembly has a certificate (C of C, or CMTR) for verification.

In addition, each valve, with its components, is tracked to its source with historical records maintained for a 10-year minimum.

We strongly believe the safety of our employees must be a paramount concern for everyone in the organization. Our people are the true wealth of our organization.

The purpose of our Cornerstone Valve safety program is to keep our most important asset, our people, healthy and safe. This effort is ongoing and continually refined. Therefore, changes may occur from time to time due to updates of our safety manual.

This Safety Manual should be considered a “living document” with changes as necessary or the work environment dictates. Employees will be informed and trained as new information incorporated into this safety manual. Also, employees are authorized and obligated to pause any unsafe task until somebody can resolve the safety issues.

Cornerstone Valve’s safety manual provides all employees of our organization with safe operating practices, guidelines, and rules to be used in our daily operations. In addition, they specify standards of behavior, procedures for work tasks, and safe work requirements.

Users of this manual should understand that this manual is only a safety guideline. There can be no substitute for a positive work attitude and individual awareness of the work environment.

  • Cornerstone can design, engineer, and manufacture API specs.
  • We are a USA manufacturer and made in Texas.
  • Custom make your valve and ship on short notice.