Legacy of the Terrible Triplets and Standards of the Future

Abstract

Background The history of the US offshore oil and gas industry in the Gulf of Mexico that began in 1948 has been chronicled in various articles and publication including a short online history (1) along with a somewhat more detailed account (2). During the period from 1948 until 1964, the offshore industry underwent rapid production growth and technology extensions for drilling, platforms and production systems. Advancement came through a combination of research, experience and incidents, some in the form of tropical storms and hurricanes. In 1964 Hurricane Hilda stormed through the Gulf of Mexico and either damaged or destroyed numerous production facilities. In November 1964, over 50 industry experts dealing with weather and platform design, construction and operation met at the Roosevelt Hotel in New Orleans, LA to discuss the observations coming from the impact of Hurricane Hilda. The two day meeting provided significant insight into the strengths and shortcomings of the young industry. Shortly after the meeting, a subset of the attendees began meeting under the auspices of the American Petroleum Institute as a committee designated as Committee 2. This committee put together the first edition of API RP 2A (3), a 16 page document released in 1967. Following on the API Standardization strategy established in the early 1900's of developing standards to provide for safe, reliable and interchangeable products, the committee drafted the standard to provide guidance to provide more consistency in the acceptable performance of fixed offshore platforms. In the ensuing years, the API Series 2 documents have grown both in number and in size. The present version of RP 2A is over 400 pages of guidance related to fixed platforms. Other documents have been developed over the years covering critical technologies such as tubular fabrication and welding. The historical focus of the API Series 2 documents has been the structural performance of a facility. Various production system standards have been developed by other API groups, most notably the API 14 Series addressing production equipment. Many changes in the Series 2 documents have been in response to significant natural events, principally hurricanes. Prior to 1964, many companies used storm conditions expected for a 25 year design period. In the years following the Hurricane Hilda meeting, practice started to change with conditions up to 100 years being used. Though the first API RP 2A in 1967 did not define a set of metocean conditions (wind, wave and current) for design, considerable discussion continued within the industry following the November 1964 meeting as to the appropriate return period for platform design. In the late 1970's, API introduced the 100 year reference level wave as the recommended minimum conditions for design. As the industry has continued to learn more about the offshore environment, the 100 year metocean conditions have increased, which in turn has resulted in increasingly greater design conditions for platforms. Experience and technology advances continue to drive expansion of the API Series 2 documents.