Mastering Valve Standards: API, ISO, ANSI & More
2 min 7 sec read
Overview
Valves are essential in industries such as petroleum, chemical, nuclear, metallurgical, power generation, hydroelectric, and large-scale coal chemical production. The increasing demand for these products and their expanding applications highlight the importance of valve standards. Several national and international organizations have developed standards for the manufacture of valves. These include British Standards (BS), German Standards (DIN), Japanese Standards (JIS), and International Standards (ISO). Despite efforts to align US standards with international standards, inconsistencies remain, particularly between conventional US standards and ISO valve requirements. This article examines the major US valve standards bodies and the reasons for their differences.
American Valve Standards
American valve standards originated in 1915 with the ASME Boiler and Pressure Vessel Code. The Manufacturers Standardization Society (MSS), founded in 1924, has produced several valve-related standards. Key milestones include ASME B16.34 for flanged, threaded, and weld end valves and API 600 for refinery valves. The growth of global markets in the 1990s created a desire for more harmonized global standards, particularly ISO standards.
Major Valve Standards Organizations
American Petroleum Institute (API)
Founded in 1919, API is responsible for standardizing equipment for the oil and gas sector. API standards provide safety, reliability, and interchangeability and are widely used in the United States and abroad.
International Organization for Standardization (ISO)
ISO, founded in 1947 in Geneva, Switzerland, is a global non-governmental organization that promotes international cooperation and industrial standardization. ISO has 91 Member Nations and over 173 Technical Committees that develop standards to support global trade and innovation.
American National Standards Institute (ANSI)
Founded in 1918, ANSI oversees the development of voluntary consensus standards in the United States and represents American interests in global standardization efforts.
American Society of Mechanical Engineers (ASME)
Founded in 1880, ASME is a preeminent global association that creates standards to promote technical innovation and ensure public safety. The ASME B16.34 standard is essential for valve design.
American Society for Testing and Materials (ASTM)
Founded in 1898, ASTM creates and disseminates technical standards for various products, systems, materials, and services. Critical material properties and test protocols for industrial applications are defined by ASTM standards.
Non-Equivalence in Standard Development
Organizations develop standards in different ways. API standards are the result of collaboration between government officials, manufacturers, engineers, and end users. ISO standards, on the other hand, are complicated because each member nation has only one vote. Attempts to publish ISO and API standards together often result in significant changes that create inconsistencies.
Testing Standards
A key component of valve standards is pressure testing. While ISO 5208 is gaining ground worldwide, API 598 is still widely used. Guidelines for leakage testing of control valves are provided by the FCI/ANSI 70-2 standard. There are six leakage classes ranging from very loose to very tight.
Common Valve Standards
| Valve Type | Material | Standard 1 | Standard 2 | Standard 3 |
|---|---|---|---|---|
| Ball Valve | Steel | API 608 | MSS SP-72 | ISO 17292 |
| Bronze | MSS SP-110 | |||
| Pipeline | API 6D | |||
| Butterfly Valve | Steel | API 609 | MSS SP-67 | ISO 10631 |
| Check Valve | Steel | API 594 | MSS SP-71 | |
| Gate Valve | Steel | API 600 | ISO 10434 | |
| Cast Iron | MSS SP-70 | ISO 5996 | ||
| Globe Valve | Steel | BS 1873 | ISO 12149 |
Conclusion
Economic globalization requires the internationalization of standards. Different standards often complement and borrow from each other depending on the industry focus. Practitioners need to select standards that are aligned with specific product requirements to ensure compliance and optimal performance.
FAQs
- Why do different valve standards exist?
- Different organizations focus on various needs, leading to different standards.
- How often are valve standards updated?
- Typically every five years, but it varies by organization.
- What is API 600?
- A critical standard for steel gate valves in petroleum and gas industries.
- How do ISO and API standards differ?
- ISO involves international voting, while API is US-focused.
- What is the most used pressure testing standard?
- API 598, though ISO 5208 is also popular.
