API 6A718 Work Group on Addition of Nickel Base CRAs

API SC6 Winter 2013 Meeting

Paul Maxwell

Objective• Provide requirements for Age Hardened Nickel

Base alloys used in the manufacture of API 6A pressure-containing and pressure-controlling components to assure they are not embrittled by the presence of an excessive level of deleterious phases and meet minimum metallurgical quality requirements.

• These additional requirements include detailed process control requirements and detailed testing requirements.

Working in Conjunction with

API5CRA Work Group on

Adding Precipitation Hardenable Nickel Base Alloys to API5CRA

38 Participants

Representing 27 Companies

4 - API6A 718 Work Group Meetings

4 - API5CRA Work Group Meetings

Additional Sub-group meetings working on;Microstructure, NDT, Heat treatment, etc.

Progress

Scope and Purpose

Chemical Compositions

Manufacturing Procedures

Heat Treatment Procedures

Mechanical Properties

To Be Resolved

Microstructure Requirements

Grain Boundary Precipitate Acceptance Criteria

Photomicrographs – Informative

Microstructure IssueGrain Boundary Precipitates Believed to be Detrimental to Hydrogen Embrittlement Resistance

No Data Available to Indicate what level of grain boundary precipitates might be acceptable

No Agreed upon Test Method for Hydrogen Embrittlement

No Quantitative Test Available for Determining Susceptibility to Hydrogen Embrittlement

Rating of Microstructures is Qualitative and Subjective

Microstructure Sub-Group Working on Resolution of Grain Boundary Precipitate Issue

Next Work Group Meeting Pending Outcome of Microstructure Sub-Group

If Issue Can Not be Resolved Sub-Group will Proceed Recommending that the Grain Boundary Precipitate Requirements be Omitted until Hydrogen Embrittlement Test Results become Available

NEXT STEPS

API 6A718 Work Group on Additional Etchant for Alloy 718

Has Been Rolled in to Work Group on Addition of Nickel Base CRAs

API 6A718 Work Group on Higher Strength Classes on 718

On Hold

• Concern that 140 ksi 718 is Prone to Hydrogen Embrittlement

• Awaiting Agreed Upon Test to Compare Hydrogen Embrittlement Resistance