I knew there was a big red sign on the fence that said no cameras were allowed in the area by the lock, so I left the camera in the van. Thus I was not able to take pictures or video of the crane lifting a steel cylinder that was about twice as tall and twice as wide as the man standing next to it. The crane swung around and set it down on the barge. It then picked up another cylinder that I had noticed was laying on the barge. The crane lifted the new one up and swung it into position. I figured it would take a while to lower the new part in place, so I left. On my way back to the van, it occurred to me that I could play games with the rules and take pictures from outside the fence through the gate. So I grabbed the camera and trotted back up to the top of the sidewalk. To my surprise, they already had the part down in place by the time I got back.
It looks like they were still unfastening the orange rigging.
|Zoomed in on the shot above.|
And leaning over a handrail to get a shot from the other side of the tree was pretty well destroyed by the fence.
I took the crane photo while rushing back to Brandon Road to get a picture of the recreational boat I saw entering the lock while I was driving to the parking lot. It turns out that there was already a tow in the lock. By the time there was a break in the traffic so that I could step out on the bridge to take a picture, the gate had started to close.
A towboat had just left the upstream gates because I saw the gates were still closing. So I waited until a lock crew of three people walked by me. When I asked some questions, the crew member with an Army Corps of Engineer shirt stayed to answer them. First of all, the operation I saw on June 7 was the replacement of a floating tie-up. So the crane was lifting something heavy enough that the "twice the height and width of a man" cylinder would sink to its top. That cylinder had a little cylinder attached to one side of its top. That would be the tie-up.
|Closeup from 2712|
|Camera resolution from 9073|
On June 21 I made another trip to the lock to see what the crane was doing. It looked like it was doing nothing. It was parked in the same place and there were no workmen in sight even though there were about 10 pickup trucks parked on the access road. The USACE person I talked to on June 15 said they would build the bulkhead and then wait for the gate repair. When I asked when the gate would be repaired, he said the had no idea because it depended on what other gate work needed to be done by the USACE. He implied it could be a long wait because their gate problem was rather minor.
|Closeup of 9311|
Railroad Street trying to grab pictures in gaps between the weeds. Below are closeups from the best photo from each pass.
We can see the two cranes are probably working on different projects. If you look at the satellite photo above, the 777 is on the dam side of the point created by the dam and lock walls. The yellow crane is on the dam itself.
|Steve McGee posted|
What was the idea behind using boom cylinders as opposed to cables? Any loss in lift by the cylinders pulling it up instead of pushing?
[From the comments, it seems the motivation for using rams was that it could boom up and down faster than a "cable bridle" design. But they had boom deflection because the attachment point was a lot closer to the house than is the case with cable attachments. Some liked the 777, some hated it. It was the only Manitowoc design that used hydraulic rams to control the boom.]