The API is the English abbreviation of the American Petroleum Society (American Petroleum Institute), founded in 1919, is the first National Business Association in the United States. An important task of the API is to ensure the safety, reliability and interchangeability of the equipment used in the oil and gas industry. Because the API has a high reputation both domestically and abroad, its technical standards for petrochemical and oil production machinery are adopted by many countries, which is recognized by the U.S. Department of Commerce and the U.S. Trade Commission as an oil machinery certification body. Currently, we have members from all over the world, including exploration and production, transportation, refining and marketing.

    Today, the API has developed into an integral part of the world's oil industry, not only in the United States, but increasingly. In general, API standards are reviewed, modified, reconfirmed, or withdrawn at least once every 5 years. Sometimes the review cycle may be extended once, but not longer than 2 years.

    When the standards of the professional committees need to be updated, the voting members from various countries designated or volunteered to participate in the ballot (available letters), over 2/3 of the votes are counted, in addition to authorized reprint extension, API standards from the date of publication, 5 years later no longer valid. API publications are divided into more than 10 categories, including: 57 specifications, 550 standards and thousands of recommended rules, decrees and so on.

    Its normative standard mainly for several major categories:

    1. Oil equipment design and manufacture;

    2, oil equipment use and maintenance;

    3, drilling and oil production operations.

    API certification Outline logo in the international also enjoy a high reputation, divided into four categories, namely:

    icp--Personal Qualification Certification,

    API qr--Quality System certification,

    monogram--Logo Outline certification,

    tpcp--Training Qualification Certification. In the fields of petroleum, petrochemical and natural gas, its monogram and Quality system API Spec Q1 is recognized not only by ISO but also by the API Quality system for free ISO 9000 certification.

    The oil machinery products wearing API logo are not only considered to be reliable but also have the advanced level mark, and have become the pass certificate of the product to the international market. The API does not require mandatory laboratory testing for products that apply for certification, but the API proposes 57 detailed specifications for various equipment involved in oil and gas collection and processing industries. For example, the 6D specification involves pipeline valves, including ball valves, gate valves, check valves, etc. These specifications specify the minimum requirements for the product to meet.

    Although no mandatory detection, but by the API personally assigned by the auditor will carefully check the products submitted by the manufacturer, "Quality Manual", and special process control (such as welding, heat treatment and nondestructive testing, etc.) have mandatory requirements to ensure that the factory in the production process in line with the API product Specification system.

    Specification for API 6d-2014 piping Valves

    Specification for API 6a-2010 wellhead devices and tree production equipment

    API 527 Metal--Sealing of metal seal safety valve

    API 528 Safety Valve Nameplate

    API 529 Flange Connection malleable iron making plug valve

    API 589 valve Packaging materials fire test

    API 594-2010 pair Clamp type, lug pair clamp type and double flange type check valve

    API 595 Flange Connection cast iron gate valve

    API 597 flange or butt welded steel shrink gate valve

    API 598-2009 valve Inspection and test

    API 599-2013 flange or butt welded steel plug valve

    API 600-2015 flange or butt welded end bolted bonnet steel gate valve

    API 602-2015 Steel gate valve cut-off and check valves for petroleum and natural gas industry

    API 603-2013 corrosion resistant, flanged end steel gate valve

    API 604 Flange Connection Ductile iron gate valve

    Fire resistance test of API 607-2010 soft seat valves

    API 608-2012 threaded end, butt weld and flanged end metal ball valve

    API 609-2009 Butterfly Valve API 621 Metal Spherical inspection valve realignment (according to ASME)