When designing a pipeline system, the complete pressure containing system should be designed in a consistent manner. In practice, there are code breaks that may violate such a consistency. One such point is at the landfall, or shore crossing.
In Australia, offshore oil and gas pipelines are designed to AS 2885.4. Whilst some specifics are addressed in this document, it largely refers to the globally used standard for submarine pipeline systems, DNV-OS-F101.
Applying this set of standards has proven to be effective for the many Australian pipeline systems which travel from offshore to onshore and necessitate a shore crossing design and construction. However, lessons learned from several projects have prompted the need for making some changes in both these documents.
A research project was undertaken in this regard, and an engineering guideline for pipelines crossing shorelines and waterways was written based on the research findings. This guideline was used to initiate a discussion on proposed changes in AS 2885.4 and DNV-OS-F101.
The changes, which have now been incorporated in both standards, result in a unified approach to defining the interaction between the Australian Standard and the International Standard for pipeline engineering and design in the shore crossing zone.
The changes in the wording of both documents are one part in ensuring continual improvement in safety and reliability levels of our national offshore to onshore pipeline network. The second part requires both the offshore and onshore pipeline industries to further enhance their collaboration for a common cause.