I wonder how much it will fetch on eBay. One of the Channel Tunnel boring machines sold for £39,999 in 2004. http://news.bbc.co.uk/1/hi/business/3620673.stm
These are usually custom made one off machines that don’t have much of a life span beyond each project.
That was on some level the whole point of the boring company Elon said it was crazy that these machines were discarded or sold for scrap.
That said since recovering them would be much easier than landing a rocket I don’t know if there is actually financial motivation to recover them.
When they are sold they are usually sold for their effective scrap weight (metal worth minus the cost of getting them offsite and breaking them down).
People say this all the time but as someone who tends to follow quite a few tunnelling projects I can't recall one in recent memory. Typically TBMs are scrapped or returned to the manufacturer for refurbishment.
Yeah, I don't like that thinking.
I don’t imagine the paint for the Sistine Chapel ceiling cost much compared with the cost of painting it.
What I don't like is the thinking of people who rush for the sign off, and paycheck date.
These machines are also custom built for the diameter, soil type and probably a plethora of other variables so it’s unlikely that you could reuse them.
They are also not built to be recovered and reused from what I gather which complicates things further.
What's there to break? The cutters on the face of the TBM, and bearings would likely be replaced few times during boring. Aside from that, what's there to break? Hydraulics is sure to outlast even the longest boring.
Pumps, gearing, sealing, etc should all be easily replaceable.
These machines are constantly serviced and aren’t operated one minute past their life spans.
I really don’t think you understand how many hours these things operate for....
To put things into perspective machines have a single digit meters per hours top speed and not high single digits to boot, and if you are digging in rock you are looking at sub meter per hour figures.
If you have a source to contradict this I’ll be happy to read it but honestly every source from articles to documentaries pretty much paints the same picture these machines aren’t worth their weight in scrap once they are done with.
Then consider the Bertha problems in Seattle. Two year delay because they needed to dig a rescue pit to get at it after it broke down. Ask would you want to start a tunnel project with an 'used' TBM? Likely not.
https://commons.wikimedia.org/wiki/File:TBM_Cutter_Head_at_C...
I think I remember reading back in the day that they buried/parked the machines near the center of the Channel where the French side and the English side met at the middle.
EDIT: Dogma replied on this as I was typing
"In December 1990, the French and British TBMs [tunnel boring machines] met in the middle and completed the Channel Service Tunnel bore. In all of the tunnels the French TBM was dismantled while the U.K. TBM was turned aside and buried"
I wonder if it was simply time management to have both sides meet at the middle or politics/symbolism. The former?
That tunnel is over a kilometre long, and they met in the middle of a hill!