[jescabrera]

I'm looking for a procedure for the nitrogen purging of pipelines after hydrostatic testing. Please advise.

[proinwv]

Could you give us more detail please.

[jescabrera]

Direct-buried chilled water and steam/condensate piping that will be installed but will not be in service for some time. We'd like to dry the inside of the piping after hydrostatic testing and then "pickle" the piping until the system is placed in service.

[proinwv]

Well the foremost issue that I find is how will you know that the line has been properly dried? Is the line very long? Being buried that would make it more difficult, especially considering that there might be low spots that accumulated moisture.

The purge would be simple. Inject at one end through a flowmeter to see the flow rate.

In tank work there are various methods to determine how much purge is needed to purge.T y this reference:

Purge reference

Otherwise you might search further.

[proinwv]

I am not sure that the hyper link is working. It seems that the link is dead. Since this was posted originally for open use on the internet, and I made a copy of it, I am attaching the file.

Attached File(s)

•  PURGE_WITH_NITROGEN.doc (234.5K)
  Number of downloads: 123

[fallah]

The purge would be simple. Inject at one end through a flowmeter to see the flow rate.

Would you please explain above in detail?

[jescabrera]

Thanks for the information but could you please provide more information? For example, are there any parameters such as the temperature of the nitrogen that needs to be injected, the flowrate, the types of fittings to use, etc.

[proinwv]

Please excuse the bluntness, but if you are asking these questions one would question whether you should be taking on this project.

I suggest that you consult with some experienced engineer(s) in your organization, or engage the services of a consultant.