Metering Stations

[engrom]

This question is to get some clarity on pipeline engineering responsibility within the limits of a gas metering station. In Australia, the design and operation of pipeline in accordance with AS2885. AS2885 has strict regulatory requirements for operations, maintenance and integrity management. The station pipework is designed to AS4041 which means there is clear distinction between what is designed to AS2885 and AS4041. My question is that is the pipeline engineer responsible for the integrity management of station pipework (above ground)designed to AS4041. Station pipework is outside the pipeline design spec break and not in the line of launcher and receiver.

 

[BigInch]

If outside the spec break, it would be logically difficult to assign responsibility to the engineer working the other side of the line, although I poke my nose wherever I want. What's your company's policy? That'll count more than a code break. I'm usually happy if I can verify that process is giving me proper pressure protection and not some stupid HIPS, or if not, I threaten to install a relief and shutdown valve on my side of the line. That usually wakes them up.

What would you be doing, if you knew that you could not fail?

 

[engrom]

BigInch - thanks. Company policy is to comply with the code requirements and this case probably falls in a grey area due to the overlap of codes. AS2885 is not specific on the responsibilities of station equipment, but it addresses the details of station design. So the opinion from Pipeline engineer is that the station pipework and associated equipment within the station boundary are within pipeline engineer's responsibility irrespective of spec break (note the pipework is designed to AS4041). However, the metering station consists of filter vessels, relief systems, instrumentation and control systems which do not fall in the competency of a pipeline engineer. Pipeline engineer is of an opinion that all engineering changes within a station requires his final approval.

AS 2885 has specific requirements and approval process to meet, but would be helpful to get some clarity from industry experience.

 

[BigInch]

My problem is that I don't have the AS specs. Obviously on a complex project cooperation amongst a number of experts from different disciplines is needed.

I do not believe, nor is it IMO typical industry practice, that a pipeline engineer is justified in asking for right of approval of all changes made in a station, although his input, as I believe my own is, on topics of what vessels and controls are required and how they should work to ensure proper operation and safe start-up and shut-down and that all equipment interacts with the pipeline in a proper manner should certainly be taken into advisement. Given the low levels of experience from other disciplines in their dealing with pipelines as part of a project I see these days, I would suggest serious consideration of his recommendations is in order, but control over all mods in a station, even I would find a bit extreme. Believe me when I tell you that there are far too many pump engineers that think they can size a pump without a system curve, process engineers that don't know the viscosity of water is different than diesel, many vessel engineers that think they can size a slug catcher without knoweledge of the flow regieme and pipeline profile and even far too many control engineers that don't have any idea what a pipeline SCADA system needs to do to prevent waterhammer, or for that matter want to use HIPS instead of saving 30% of pipeline steel costs, far too many piping & plant layout types around that think you can put pipeline pumps smack in the middle of the tank farm. So all in all, and given my above observations, I could easily go so far as to recommend that you shut everyone else up at least long enough until they have heard what he has to say.

What would you be doing, if you knew that you could not fail?