What Is API 682? History and Key Points of the Fourth Edition

API 682, also known as ISO 21049, is the reference standard for mechanical seals and pump fluid systems in the oil, gas, and chemical industries. Understanding this standard helps to choose seals and write technical requirements more accurately.

Brief History

Initially, information about seals was included in the API 610 pump standard. In the 1990s, API 682 was separated into its own standard, with more details. The third edition (2004) was unified with ISO 21049. The fourth edition took nearly six years to draft and is approximately 260 pages long, compared to around 200 pages in the previous edition.

Main Points of the Fourth Edition

• The product coding system has been modified, still retaining the three parameters Category, Arrangement, Type, and adding material and shaft diameter information.
• Both types of silicon carbide (reaction-bonded and sintered) are used as default seal face materials.
• For the first time, there is a diagram based on risk and hazard codes to select the seal configuration.
• There is a regulation on the minimum fluid supplementation period of 28 days.
• Red buttons on the connection ports help identify seals according to the fourth edition.

Three Basic Configurations

Arrangement 1 is a single seal, Arrangement 2 is a double seal without pressure increase, Arrangement 3 is a double seal with pressure increase.

Note

Please check the latest version directly on the API website before creating technical requirements.

References

Pumps and Systems, EagleBurgmann, World Oil. The article is compiled and reinterpreted by SNS-VN.