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Load testing

RibStaThiok's Photo RibStaThiok 05 Jun 2016

How often is load testing required at the mountain you work at? Have you ever encountered any issues when doing the load test?
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Aussierob's Photo Aussierob 06 Jun 2016

Canada requires a load test every 5 years. For me that's about 5 lifts per year. Usually we don't have serious issues, some of the downloading lifts can take a while to get a brake setup that works in all load cases. Acceptance tests with modified or new lifts can be a little more interesting as sometimes you find unexpected stuff that needs to be redesigned or changed in order to work correctly.
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liftmech's Photo liftmech 07 Jun 2016

In the States, ANSI B.77 requires a dynamic test every seven years. My experience has been much the same as Rob's, especially the part about modified or relocated lifts ;)
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2milehi's Photo 2milehi 09 Jun 2016

Same thing for Keystone (7 years), but with certain upgrades a load test is required (major modification). I am going to add to this year's test - remove the driveshaft for the electric motor and chech stopping distance. This is in case a motor craps out during the season. If the lift behaves well then we could run it to the public.

Always good to have another ace up your sleeve.
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liftmech's Photo liftmech 09 Jun 2016

I like that idea. I'll have to bring it up for our tests this summer.
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Aussierob's Photo Aussierob 09 Jun 2016

Depending on the lift profile, you will find that the lift will fail without the inertia of the rotor of the motor in the system. Uphill fully loaded stops are likely to be too short without the inertia of the motor driving through the service brake. We have spare motors for a lot of our lifts and we make a specific inertia/brake disk to match the original motor to the spare so the braking performance is the same.
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RibStaThiok's Photo RibStaThiok 09 Jun 2016

Just don't do what they accidentally did on the rollback testing/study on the old double chair Riblet Eskimo lift at Winter Park!
https://www.youtube....h?v=FwPP4i7ENvQ

Admin note: The destructive test was a planned test - nothing accidental. Results were expected, however the speed of the results was faster than expected.
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2milehi's Photo 2milehi 10 Jun 2016

To the OP's other questions - yes we have run into issues. The downloading lifts are the finicky ones. You also get to thoroughly check the manufacturer's procedure with the brakes and confirm that they hold. If a brake is not 100%, the load test is a great time to make it right.
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RibStaThiok's Photo RibStaThiok 10 Jun 2016

View PostRibStaThiok, on 09 June 2016 - 09:20 PM, said:

Just don't do what they accidentally did on the rollback testing/study on the old double chair Riblet Eskimo lift at Winter Park!
https://www.youtube....h?v=FwPP4i7ENvQ

Admin note: The destructive test was a planned test - nothing accidental. Results were expected, however the speed of the results was faster than expected.


Yes it was accidental. At least that portion of the test. Listen to the wording starting at 20 seconds and ending at 30 seconds.
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