API TR 1PER15K-1
Protocol for Verification and Validation of High-pressure High-temperature Equipment
|Publication Date:||1 March 2013|
This report focuses on an evaluation process for high-pressure high-temperature (HPHT) equipment in the petroleum and natural gas industries which includes design verification analysis, design validation, material selection considerations, and manufacturing process controls necessary to ensure the equipment is fit-for-service in the applicable HPHT environment. HPHT environments are intended to mean that one or more of the following well conditions exist:
a) the completion of the well requires completion equipment or well control equipment assigned a temperature rating greater than 350 °F or a pressure rating greater than 15,000 psig;
b) the maximum anticipated surface pressure or shut-in tubing pressure is greater than 15,000 psig on the seafloor for a well with a subsea wellhead or at the surface for a well with a surface wellhead; or
c) the flowing temperature is greater than 350 °F on the seafloor for a well with a subsea wellhead or on the surface for a well with a surface wellhead.
NOTE In high-temperature, low-pressure applications, not all methodologies presented in this document may apply.
The design verification process focuses on the analytical
methods to achieve design verification by calculating the
performance limits of a design (system, subsystems, and
components), including its service life and material selection. The
design validation process focuses on evaluating the potential
failure modes of the equipment, the effects/consequences
The design verification and validation protocols in this report should be used as a guide by the various API subcommittees to develop new and revised standards on equipment specifications for HPHT service. This report is not intended to replace existing API equipment specifications but to supplement them by illustrating accepted practices and principles that may be considered in order to maintain the safety and integrity of the equipment. This report is intended to apply to the following equipment: wellheads, tubing heads, tubulars, packers, connections, seals, seal assemblies, production trees, chokes, and well control equipment. It may be used for other equipment in HPHT service.
Annexes to this report provide additional information on the following:
- Annex A provides example HPHT material property data,
- Annex B is a compendium of published metallurgical-relate
- Annex C provides a detailed explanation of the failure mode and effect analysis (FMEA) process,
- Annex D contains technical information on the considerations for the selection of castings and forgings,
- Annex E provides information on the important elements of a quality management system for manufacturers of HPHT equipment.
Existing Designs and In-service Equipment
Previous standards exist for equipment designed for HPHT conditions. These include API and ASME publications and date back to such documents as AWHEM Std 6 (June 1957), AWHEM Specification for Ring Joint Flanges for Drilling and Production Service for 15,000 psi Working Pressure. Existing practices have resulted in successful, field proven equipment. Further enhancements to these specifications may include additional analytical and testing techniques referenced in this document. This document does not imply that existing equipment is unsatisfactory for use or should be replaced, or that additional components could not be made to the same existing design. Where the existing design, analysis processes, and procedures used in the design and manufacture of equipment fall fully within the scope of an existing API standard, the equipment is deemed to be fit-for-service. Changes in the functional specifications require reevaluation of the existing design. New or revised standards for equipment used in HPHT service should consider the history of equipment manufactured to prior standards and address future use of that equipment as well as new equipment made to the same design. Additional documentation of selected industry experience in HPHT well completions is available in the Bibliography.
Requirements for existing HPHT equipment are covered in many existing API standards. A listing of the standards that cover requirements for existing HPHT equipment as well as some standards that do not address HPHT requirements but are frequently invoked are provided in Table 1.
This technical report describes an evaluation process for HPHT equipment to ensure the equipment is fitfor- service in the applicable HPHT environment. This report does not supersede current API standards but discusses additional or alternative methods of design verification and validation.