We use what is called a skidding system for moving heavy (100 ton range) transformers off of trailers and onto foundations in substations.
This is a similar concept but different design: Ours is essentially 2 rails made from heavy I-beams. Each beam has a yoke with holes that pins go into, the pins go through the web and reinforcing plates of the beam to push against, and then cap channels ride on top of the beams with the load on top of them. Mounting points connect the yokes to the cap channels via large hydraulic cylinders. When activated they push or pull the cap channels along. The sliders are, with extensions, 18'6" long and have a 6" contact surface with the beam (roughly) so I'm figuring 110 psi at best case with 100 ton on it, sometimes they only fit in 8' of the slider however at which case we're looking more at 350 psi. The unit itself moves very slow, the rate of travel over the plastic is only maybe 2'- 2.5' a minute.
In the past we've used soap flakes as a lubricant but we lost access to those. So we changed to liquid soap by the barrel, but in summer the heat causes it to turn into more of a tacky glue than a lubricant, so we went to grease on top to lower the coefficient of friction. Due to environmental concerns the client would prefer we move to a non-grease system, and due to messy clothes we'd prefer that too, but other lubricants aren't much of an option as this system performs in direct sun on 100 degree days and covered in snow in -15 degree days all depending on when things have to be done. So far none of the lubricants have worked as well in all situations.
So we decided to hire a plastics company to choose the proper plastic for us so we could line the top of the beams. I don't have any paperwork as this was a few years ago, and the plastics company has since went out of business, but we finally got the system downed long enough to switch over to the mounted plastic. The plastic is grey, supposedly has lubricants embedded into it, and seems to be very dense, but I was told it was not UHMW as that was brought up in a meeting and they suggested this instead. Based on that I have no clue what it is. They said it was used as turntable wear pads for heavy equipment like draglines but I find that hard to believe given how hard it's moving for us.
What I do know is that when we started doing a test slide with only 50,000 lbs, the whole system began to chatter wildly. The test load was bouncing slightly. I also know that if the plastic gets wet, instead of becoming slippery it turns more into a tacky surface. We tried lubricating the surface with silicone spray as that's "less messy" in the customers view, but it had no effect.
My questions are threefold:
1) Does anyone have an idea what plastic this is based on the little info I have?
2) Is there a different option we could be trying for lubrication on the plastic that might work better than grease/silicone spray without being super messy that will work with the plastic instead of fighting it?
3) Is there a different plastic we could try given the loading that will perform in all temperatures without the need of grease (or without any lubricant?)?
This is a similar concept but different design: Ours is essentially 2 rails made from heavy I-beams. Each beam has a yoke with holes that pins go into, the pins go through the web and reinforcing plates of the beam to push against, and then cap channels ride on top of the beams with the load on top of them. Mounting points connect the yokes to the cap channels via large hydraulic cylinders. When activated they push or pull the cap channels along. The sliders are, with extensions, 18'6" long and have a 6" contact surface with the beam (roughly) so I'm figuring 110 psi at best case with 100 ton on it, sometimes they only fit in 8' of the slider however at which case we're looking more at 350 psi. The unit itself moves very slow, the rate of travel over the plastic is only maybe 2'- 2.5' a minute.
In the past we've used soap flakes as a lubricant but we lost access to those. So we changed to liquid soap by the barrel, but in summer the heat causes it to turn into more of a tacky glue than a lubricant, so we went to grease on top to lower the coefficient of friction. Due to environmental concerns the client would prefer we move to a non-grease system, and due to messy clothes we'd prefer that too, but other lubricants aren't much of an option as this system performs in direct sun on 100 degree days and covered in snow in -15 degree days all depending on when things have to be done. So far none of the lubricants have worked as well in all situations.
So we decided to hire a plastics company to choose the proper plastic for us so we could line the top of the beams. I don't have any paperwork as this was a few years ago, and the plastics company has since went out of business, but we finally got the system downed long enough to switch over to the mounted plastic. The plastic is grey, supposedly has lubricants embedded into it, and seems to be very dense, but I was told it was not UHMW as that was brought up in a meeting and they suggested this instead. Based on that I have no clue what it is. They said it was used as turntable wear pads for heavy equipment like draglines but I find that hard to believe given how hard it's moving for us.
What I do know is that when we started doing a test slide with only 50,000 lbs, the whole system began to chatter wildly. The test load was bouncing slightly. I also know that if the plastic gets wet, instead of becoming slippery it turns more into a tacky surface. We tried lubricating the surface with silicone spray as that's "less messy" in the customers view, but it had no effect.
My questions are threefold:
1) Does anyone have an idea what plastic this is based on the little info I have?
2) Is there a different option we could be trying for lubrication on the plastic that might work better than grease/silicone spray without being super messy that will work with the plastic instead of fighting it?
3) Is there a different plastic we could try given the loading that will perform in all temperatures without the need of grease (or without any lubricant?)?
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