AIS shows this warning pretty quick

[newtothis]

It’s actually 3 out of the 4 pipelines that have simultaneously had seismic events followed by a major leak. Accidental seems very very unlikely as does amateur terrorism or environmental protests.

Once is happenstance, twice is coincidence, three times is enemy action. - Ian Fleming

 

[WindyWindyWindy]

I wouldn't be so quick to rule out amateurs.

 

[boomerangben]

I wonder how long the pipes will last with raw seawater inside and with no corrosion inhibitor.

 

[Rappey]

I wonder how long the pipes will last with raw seawater inside and with no corrosion inhibitor.

There are suggestions that the pipes will be written off due to corrosive sea water inside causing rust.

 

[Martin_J]

That was a suggestion indeed that they might be written off one sea water gets in. hence me wondering in an earlier post if they'd ever been full of sea water at the time of their construction and welding together under the sea...

I didn't get to finish reading how they were constructed so didn't get to the answer.

 

[Daydream believer]

That looks like a major hazard. Apart from the obvious risk of explosion and asphyxiation if you sailed over it you would suffer a loss of buoyancy.

You might become very buoyant, if someone lobbed a fag out of a helicopter when you were sailing over the break
watch the first bit

 

[Rappey]

and welding together under the sea...

From the clips I've seen on various non uk news channels the pipes appear to be bolted then welded by machine on board the pipe laying ship as they are slowly fed out the stern .
I have not watched this clip as every time I FF I get spammed by another two adverts giving me more adverts than video. I have noticed that links watched on threads within this forum seem advert free ?

 

[boomerangben]

From the clips I've seen on various non uk news channels the pipes appear to be bolted then welded by machine on board the pipe laying ship as they are slowly fed out the stern .
I have not watched this clip as every time I FF I get spammed by another two adverts giving me more adverts than video. I have noticed that links watched on threads within this forum seem advert free ?

It’s a long time since I was involved in pipelines and then it was associated with subsea tie backs and not land to land pipelines. However I think it was rare if not unheard of for flanged connections on pipelays other than for connecting lay down heads/pig catcher/launcher or perhaps some intermediary connection. (Lay down heads are essentially somewhere to attach the shackle and wire to lay the end down, often with a pig launcher/catcher) so I would imagine this pipeline would have been welded.

 

[WindyWindyWindy]

There must be some plan to repair them? Were they made by Apple?

Some parts of these pipes are in about 6m of water, presumably buried, but a wayward ship could ding one. In which case the plan is surely not to lay an entirely new one?

 

[boomerangben]

That was a suggestion indeed that they might be written off one sea water gets in. hence me wondering in an earlier post if they'd ever been full of sea water at the time of their construction and welding together under the sea...

I didn't get to finish reading how they were constructed so didn't get to the answer.

Not sure about this pipeline, but on the subsea pipelines I worked on, they were laid empty ie air only, once they were laid, they would be flooded by running a pig (looks like a dumbbell with plastic discs to make it water tight in the pipe). Sea water which is treated with corrosion inhibitors, O2 absorbers, biocides and sometimes dye is pumped in behind the pig until the pipeline is full.
It may be that this pipeline wasn’t done like that though

 

[Martin_J]

Looking at the website I found and linked to earlier (but never had time to read), the three very long sections did have watertight and airtight ends... then they were joined underwater.. so perhaps there never was any sea water in the pipes after all.

It looks like the full story is there but sections eight and nine seem to cover the physical pipe part...

Nord Stream Pipeline - Pipe Laying of the 1,224 kilometre long natural gas pipeline

Nord Stream Pipeline - Tie-Ins and Hyperbaric welding

It still takes some figuring out what to do with any water that does get in. One end has to accept a load of rusty sea water coming out I guess.

 

[boomerangben]

You might become very buoyant, if someone lobbed a fag out of a helicopter when you were sailing over the break
watch the first bit

Not allowed to smoke in helicopters anymore! Beside the two blooming great blow torches on the roof would quite happily turn a cloud of gas into a bang!!

 

[NormanS]

As a matter of interest, how is a gas or air filled pipeline held down?

 

[boomerangben]

As a matter of interest, how is a gas or air filled pipeline held down?

A layer of reinforced concrete coating which also provides some protection if it is exposed on the seabed

 

[jamie N]

A layer of reinforced concrete coating which also provides some protection if it is exposed on the seabed

Yup, for some unknown reason it's known as "Weightcoat".

 

[Bilgediver]

Drop a pig in with a payload, set the counter on the triplex pump,

That was my thought when I read about the incident. No local evidence except the deformation of the pipe.

 

[Porthandbuoy]

That was my thought when I read about the incident. No local evidence except the deformation of the pipe.

Pig won’t move unless the gas is flowing. I thought the pipelines were shut off.

 

[Bilgediver]

Pig won’t move unless the gas is flowing. I thought the pipelines were shut off.

You did not read an earlier post or misunderstood it. The pig is normally propelled by water or other fluids which are non compressible. By counting the pump strokes pumping along and knowing the pipe dimensions the location of the pig is known . This is important when doing maintenance inspections. Pipe inspections are not| done with oil or gas in the pipe.

 

[luke collins]

Makes you wonder if they sent some pigs down the pipe with explosives on them and then blew the pipes open from within. Either way I would imagine it will take years to make them live again if gas export was ever re established to the EU.

 

[NormanS]

As far as Russia is concerned, if guilty, it's a classic case of "cutting off your nose to spite your face".