Pipeline vs Piping
Does AS2885 define pipeline vs station piping based on pipe length? (e.g. "if longer than 5 pipe joints then to be designed to AS2885", or say designate in the Standard a XXXm length gas pipe inside station / fenced boundary between two facilities).
The AS 2885 suite applies to pipelines not piping .
The delineation between pipeline and piping is not based on length of pipe / piping.
AS2885 does not define if a pipeline section is "pipeline" or "station piping" based upon its length. It would be difficult (read nearly impossible) to apply a standard "rule" to all the possible scenarios around station pipe versus "pipeline" based solely upon the length - e.g. some facilities have long lengths of "pipeline" within them.
It is understandable to call a buried section of pipe within a station a "pipeline", particularly if similar integrity controls, such as ILI, are used.
Fundamentally though, a "pipeline" crosses property boundaries into locations not controlled by the pipeline Licensee.
Pipelines are generally long distance, larger diameter, high pressure, buried, and traverses through public land that the operator does not have full control over.
Piping is small diameter, short distance, above ground, and usually fenced off from the public.
For AS2885 pipeline systems, piping is designed to AS4041 or ASME B31.3. See AS2885.1 Clause 6.3 Station Design, or Stations
The material specifications are very different for pipelines to piping. See AS 2885.1 Section 3 Pipeline Materials.
The management of risks (threats) to pipelines are very different for pipelines compared to piping. This is mainly because pipelines traverse lands used by the public which are not controlled by the Licensee/operator of the pipeline. See AS 2885.6.
Aside Info: ASME B31 committees (all parts) are represented by piping specialists in the Australian industry. In 2019, work was done on “Development of B31.8 Code Content to Address Mech- and AIV in Compressor Station Piping Systems”