Hey guys we are doing a mod and reusing the Otis 138 HT gearless machines. The 500 ft/min car is 2 to 1 and due to the fan of the cables going from the drop of the machine to the car sheave, the HW 624 rope gripper can't work properly. The guys tried to install the rope gripper in the overhead but the fan of the cables drags the rope gripper from one side of the shoe to the other shoe depending where the car is. Otis does make a sheave brake but it is proprietary and supposedly they won't sell it or it is at some outlandish price. My idea to fix this is to put raising
beams under the machine in the machine room and then remount the rope gripper in the machine room in the normal manner. My raising beams would basically sit right on top of the existing machine beams. I am open to other ideas. Is there any third party company that makes a sheave brake. No matter how I deal with this it will be labor intensive and expensive. To do what I propose will involve having to re-rope the car but it would only be an issue on this first elevator.
I just went through exactly what you are talking about see below for some pictures. ( I will take a few close ups of the finished product )
We looked on the market for a product that would work. We came to the conclusion that we had to suck it up and raise the machine!. We then added a 1" thick steel plate on the machine beams and 5/8 bolted (grade 5 or higher ) required and mounted the rope gripper to that. We ended up using 21" 8" I beams and had to weld gussets between the I beams as well as a few other gussets on the sheave side.
I will have to admit I was a little apprehensive about the ascending car test/125% roll away but everything was tickety boo. We spent weeks pissing around trying to find another sollution to this situation. We had 12 cars to raise and in the end we got it down to a fine art! We could raise the machine install the rope gripper done in under a day!
Good Luck!
Regards
Lepricon
