API Standardization of Subsea Equipment: A Progress Report
Authors: Rickey W.P. , Croy D.G. , Hall J.E. 
Published: October 2008

API Committee 17 on Standardization of Subsea Production Systems is charged with supplying appropriate standards on subsea equipment to meet the needs of the industry in a timely fashion. This progress report covers standards issued to date and ongoing work on other standards to be issued soon. Included are summary descriptions of two recommended practices already issued and a third to be available in 1990. The main emphasis of-this report is the work on API Specification l7D, Specification for Subsea Wellhead and Christmas Tree Equipment. This specification, which will be issued in 1990, represents a major or effort by a large number of people representing both the manufacturing and operating sides of the petroleum industry.

The first document issued by API Committee 17 was API RP 17A, Design and Operation of Subsea Production Systems. This document, issued September 1, 1987, provides guidelines for design, installation, operation, repair and abandonment of subsea production systems. Figure 1 shows an outline of the RP 17A coverage. It is generally organized by subsystems of typical subsea applications. Separate sections are provided on well completion equipment, pipelines and end connections, control systems, template and manifold systems, and production risers.

The approach followed in each of these sections is to provide a system description, functional requirements of equipment in that subsystem, and to cover design considerations which should be followed. The functional considerations sections describe what each part of a subsea system should be expected to accomplish in service. For example, a subsea template system should functionally provide for the following items:InstallationLoad Bearing CapabilityDrilling and Completion InterfaceAlignmentGuidanceAbandonment Provisions

Design considerations for each subsystem are intended to assist the designer by providing guidance as to what the design should include and what elements should be considered. This document does not provide design details on how the design objectives should be achieved. As an example, the subsea wellhead section gives guidance in considering the following elements:Structural IntegrityPressure RatingSize and CompatibilityServiceRunning Tool RequirementsCompleting Exploratory Wells

In addition to the subsystem sections, API RP 17A includes sections on operations and Quality Assurance, Materials and Corrosion.

The operations section provides guidance on the following operational phases:Equipment Integration TestsInstallationProduction or Injection OperationsMaintenance OperationsAbandonment

The second document issued by API Committee 17 is API RP l7B, Recommended Practice for Flexible Pipe, which was issued June 1, 1988. Initiative for this document was taken by Committee 17 in response to the growing number of applications of flexible pipe as well as an increasing number of manufacturers. Figure 2 shows an outline of the RP l7B coverage. It provides guidelines for the design, analysis, quality assurance, storage, handling, transportation and installation of flexible pipe systems for subsea and marine riser applications.