Impact Of API 14C On The Design And Construction Of Offshore Facilities
Authors: Farrell Tim 
Published: December 2007

In recent years government regulations have exerted an increasing influence on the techniques of engineering analysis and design, which has produced such documents as API-RP-14C. API-RP-14C, produced such documents as API-RP-14C. API-RP-14C, developed by the American Petroleum Institute exemplifies the effect of that influence on a procedure by which safety systems and controls on procedure by which safety systems and controls on offshore platforms are designed and installed. This paper discusses the major areas in which API-RP-14C paper discusses the major areas in which API-RP-14C affects safety system design and construction, and recommends a philosophy for its application.

Introduction

In June 1974 the American Petroleum Institute issued Recommended Practice 14C, "Analysis, Design, Installation, and Testing of Basic Surface Safety Systems on Offshore Production Platforms." Since then the United States Geological Survey has required compliance with most guidelines in the Gulf of Mexico and in the North and South Atlantic. By midsummer of 1978 the USGS proposes to have a national order No. 5 which will reference API-RP-14C and require national compliance therewith. The intent of this recommended practice is to give the industry a standard procedure for analyzing the safety requirements needed on an offshore production facility. The standard is rather lengthy and detailed in its information and, if not used properly, can seem ambiguous and difficult to apply, the intent being to form a fail safe system which is overprotected rather than underprotected. This paper describes the proper procedures for using API-RP-14C and shows how it differs from today's industry standards. This paper also illustrates the most efficient ways (to the best of the author's knowledge) to use API-RP-14C without compromising its purpose.

SAFETY DEVICE SYMBOLS AND IDENTIFICATION

API-RP-14C uses an associative method for tagging and identifying safety devices whereby a particular safety device is symbolically associated particular safety device is symbolically associated with the process component it protects. A typical device identification (tag number) performs two major functions:it uniquely identifies both the safety device and the type, andit uniquely identifies the process component it protects.

A typical safety device identification is PSV-1-MBD-1000. The first three characters as far as PSV-1-MBD-1000. The first three characters as far as possible developed from the ANSI Standard Y-32.2 possible developed from the ANSI Standard Y-32.2 (formerly Instrument Society of America Standard S5.1). The mnemonic letters "PSV" used in the example stand for pressure safety valve. The number following those initials is the device number, which uniquely identifies the particular safety device for a particular process component. For an example of this number's application, consider two relief valves on one production separator. One relief valve would be referred to as PSV-1-MBD-1000, while the other would be identified as PSV-2-MBD-1000. (Figure 1)

The mnemonic following the device number is the process component description, which can be found in Table 2.2, Supplement 1, of API-RP-14C. In the example given, MBD stands for pressure vessel separator, and this tag would be used when describing a production separator. The last four digits of this safety device identification uniquely identify the process component, and are used at the designers' discretion. Thus, a safety device identification code can not only identify the type of device, but also what process component it protects.

It should be noted that a process component is any section of a process that can be isolated and analyzed independently, including such components as compressors, pressure vessels, and heaters.

Once KNSI Standard Y32.2 and the API-RP-14C component identification mnemonic have been mastered, the next phase in the safety analysis is to refer to the flow diagrams and identify each process component with its proper mnemonic. In process component with its proper mnemonic. In identifying a process component care should be taken to make sure the device is properly described.