Posted on 05/18/2015 10:01:33 PM PDT by smokingfrog
Now that stalled tunnel machine Berthas front end is disassembled, the damage looks worse than project experts thought and contractors will miss their goal to resume digging in August.
Not only did grit penetrate the rubber bearing seals, but the steel casings around the seals broke apart, sending fragments into the drive gears.
Some teeth are cracked in the giant bull gear, which rotates the circular drill face, as well as several pinion gears that are spun by 24 electric motors.
The news was revealed Monday morning by Todd Trepanier, administrator for the states Highway 99 replacement project, at a Seattle City Council briefing.
Bertha, the worlds biggest tunnel-boring machine, overheated and quit digging on Dec. 6, 2013. The machine is stuck near Pioneer Square, some 1,083 feet into the 9,270-foot route from Sodo to South Lake Union.
The highway tunnel has lapsed two years behind schedule, and is now estimated to open in early 2017.
Hitachi-Zosen, which built the $80 million, 57-foot-4-inch-diameter machine, is replacing or retrofitting virtually the entire front end.
(Excerpt) Read more at seattletimes.com ...
Why did it have a chance to tear itself up so badly?
/johnny
Stupid, ill-conceived plan from the get-go. I lived in Seattle area while this was being debated and clearly, the tunnel option was not only the most expensive but the least likely to succeed. So of course that’s the one they chose. Guaranteed to use more taxpayer money by a magnitude of 971,415,137,654.
Only 8187 feet to go!
I’m not sure what “retrofitting” means. But my guess is that it doesn’t include a redesign of the thing.
It is the largest boring machine ever made.
The original bearing seals were damaged during the test back in Japan. They replaced them.
Those bearing seals were damaged/broke in Seattle. I think they need a major redesign-I don’t think it is engineered properly. If they just replace the same stuff that has already failed twice they are just asking for trouble. And next time the odds are it will be under a 20-story building in the middle of Seattle.
The machine constructs the tunnel as it goes - it can’t go backwards.
Hmm, thought that you were talking about the golf club.
I said that about my first wife! HEE HEE HA HA HA HA HA.............
I lived in Seattle for 45 years before moving to a small farm in central KY four years ago. I’ve been calling this “Big Dig West” since its conception became public.
These stories just crack me up. Seriously.
It’s almost as much fun as Seattle’s arrogantly ignorant punks protesting an oil drilling rig by beating on their kayaks made from oil.
What about her sisters?
Supposedly it ran into some old steel pipe (well casing) that jammed it up and busted some gears.
Hope they got the extended warranty.
This system was only going to cost what 3.4 Billion now we are expected to pass the 40 billion dollar range shortly?
I don’t know whatever happened to Betty Butt, Bella Butt and Bathsheba Butt.
Not any more.
DANG!
Not to mention all that overtime.
It sounds like they spent the last 16 months digging a huge hole to bring the cutter to the surface. Crazy way to dig a tunnel.
That was just them trying to blame someone. The only wells there were 4-inch water monitoring wells. These machines crunch through heavy defunct oil well casing in California all the time. The bearing seal is a bad design.
I see that they will be adding some steel and stronger materials. I hope that works - but I’m doubtful.
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