This lift is one of two triple chairlifts servicing a beginner area.View down the line.Upper part of the lift line.Lower part of the line.Tower 4.Bottom terminal.Loading area.Riblet drive station without an indoor motor room.
These assemblies are the same as any other Riblet model. Alpine Valley may just have removed the opposing sheaves. Riblet only built one kind of pair bar (they did have three different models, triangle box, squashed tube, and rectangular box)and they all are capable of mounting the opposing sheave whether used in support or compression. I’m not sure why they were specified on depression assemblies- consider tower 1 on Baker’s chair 8, for example, which clearly doesn’t need opposing sheaves to keep the rope on- but there they are.
Idle speculation, but most Riblets I can recall have combo support/depression towers at load. I wonder if it’s to help protect against side load or twisting at the load ramp.
Could be, but knowing the loads on those towers I rather doubt it. Every Riblet I’ve worked on, save Baker’s original chair 1, has the opposing sheaves mounted at the portal/tower 1 regardless of whether or not they need them. They’re purely to trap the rope; if the carrier wants to twist they won’t keep it it from doing so. I’m pretty sure it was just a standard Riblet design as this is the only lift I’ve seen without them. They definitely make it harder to change sheaves as you have to remove the opposing sheave mount in order to place the rope jack. Three half-inch bolts that like to gall….
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Wow, this is the first Riblet I’ve seen with normal depression assemblies. Most are just compression.
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These assemblies are the same as any other Riblet model. Alpine Valley may just have removed the opposing sheaves. Riblet only built one kind of pair bar (they did have three different models, triangle box, squashed tube, and rectangular box)and they all are capable of mounting the opposing sheave whether used in support or compression. I’m not sure why they were specified on depression assemblies- consider tower 1 on Baker’s chair 8, for example, which clearly doesn’t need opposing sheaves to keep the rope on- but there they are.
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Idle speculation, but most Riblets I can recall have combo support/depression towers at load. I wonder if it’s to help protect against side load or twisting at the load ramp.
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Could be, but knowing the loads on those towers I rather doubt it. Every Riblet I’ve worked on, save Baker’s original chair 1, has the opposing sheaves mounted at the portal/tower 1 regardless of whether or not they need them. They’re purely to trap the rope; if the carrier wants to twist they won’t keep it it from doing so. I’m pretty sure it was just a standard Riblet design as this is the only lift I’ve seen without them. They definitely make it harder to change sheaves as you have to remove the opposing sheave mount in order to place the rope jack. Three half-inch bolts that like to gall….
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