I'm sure no less than 100 mining and mechanical engineers along with aid from NASA looked at the design of the system..
But since NASA's budget was redirected to promote good will toward Muslims all they could come up with was the pulley held by the Wal-Mart cargo strap. -----Original Message----- From: David [mailto:dlocklea...@gmail.com] Sent: Tuesday, October 12, 2010 8:30 PM To: Cavers Texas Subject: [Texascavers] The Chilean mine rescue I am posting this because the rescue is potentially related to building a cave entrance for a deep cave. Please delete this if you are not interested in the topic. By the time you read this, at least one of the miners should be out. Univision plans to show live coverage of the mine rescue for probably the rest of the night, and tomorrow. If you tune in now, you will see technicians gerry-rigging a temporary pulley near the top of the shaft to try to stop some of the wobble in their system. I bet the cable wobbles and rubs the rock shaft a lot more at 800 to 1000 feet as the capsule hangs below at 2000 feet deep and is spinning around. One report says the capsule will spin 15 times on its way out. It makes you admire the engineering at the Honeycreek Shaft. The Chilean system goes straight from the top pulley across a field where there is a giant winch with 2000 feet of steel cable. The cable looks to be an inch in diameter. Here is a recent picture of the capsule: http://www.google.com/hostednews/ap/media/ALeqM5gZlZEJmq2euuKhZ6-iOqF1YjQbIQ ?docId=e492b4ff-c4ed-45f6-b93f-e9ca017ffc6b&size=l Since they have done 4 test runs, they should be able to anticipate any problems. The victims will have oxygen mask which is a good idea. Also, one report said they would be wearing special nylon overalls. One concern I have is that since the shaft is not vertical, the capsule will be grinding the whole way along the bottom side of the rock shaft. That is going to be loud, and maybe sparks flying. I don't like the grating covering the miner at all. Also, since the shaft is not vertical the cable is going to rub on the rock, because the weight of the cable will be stretched out for 2000 feet. This rub point should move down the cable as the capsule rises, so that not the same spot in the cable is receiving abrasion. At some depth the cable should not rub. Maybe the capsule weighs enough to pull the slack out of the cable at 2000 feet? The tie-off point on the capsule has to be able to support part of the weight of a 2000 foot x 1 inch steel cable, along with all the dynamic forces of the jerking of the capsule. I bet some sophomore engineering mechanic classes get that as a test question this semester. Since the capsule is spinning 360 degrees, there has to be reinforcement in all directions. I only see 4 reinforcements at 90 degrees each Fortunately, the angle is not severe enough to cause an obvious problem. One report said only 300 feet of the rock shaft is lined. Is that going to be enough? There seem to be a lot of technicians on the ground help the head honcho. And there is quite an audience there. It is kind of like what the Floyd Collins rescue would have been like. David Locklear --------------------------------------------------------------------- Visit our website: http://texascavers.com To unsubscribe, e-mail: texascavers-unsubscr...@texascavers.com For additional commands, e-mail: texascavers-h...@texascavers.com --------------------------------------------------------------------- Visit our website: http://texascavers.com To unsubscribe, e-mail: texascavers-unsubscr...@texascavers.com For additional commands, e-mail: texascavers-h...@texascavers.com
