19 replies to this topic

[liftmech]

First you open the parking rail from its normal operational setting:

Attached File(s)

•  closed_rail.jpg (91.08K)
  Number of downloads: 34

[liftmech]

...to its maintenance position, which allows you to remove or replace a chair.

Attached File(s)

•  open_rail.jpg (93.45K)
  Number of downloads: 25

[liftmech]

Since we don't have an adjacent grip building at the Flyer, we drop the chair into the motor room and remove the grip.

Attached File(s)

•  grip_repair_2.JPG (69.71K)
  Number of downloads: 36

[liftmech]

Then we take the grip over to the top of the Eagle, where we have a TB-41 maintenance facility.

Attached File(s)

•  grip_transportation.jpg (134.99K)
  Number of downloads: 32

[liftmech]

Inside the building is a rail identical to the one in the terminals, which is where we will tear down and rebuild the grip. (I hope no-one is offended by the artwork on the rail... )

Attached File(s)

•  grip_on_rail.jpg (134.49K)
  Number of downloads: 48

[liftmech]

The grip, disassembled.

Attached File(s)

•  pieces_parts.jpg (115.23K)
  Number of downloads: 32

[liftmech]

While one person (that would be me) inspects the critical parts under blacklight (sorry, no photos of that) the other person measures the springs and inspects the support and guide rollers.

Attached File(s)

•  spring_pack.jpg (71.11K)
  Number of downloads: 28

[liftmech]

After the grip is reassembled, we measure it under certain conditions to ensure it will function properly.

Attached File(s)

•  nominal_measurement.jpg (102.79K)
  Number of downloads: 36

[liftmech]

While the grip is fully compressed, we measure the jaw opening. Poma mandates at least 5mm of clearance on both sides of the rope; thus a 42mm rope would require a jaw opening of at least 52mm.

Attached File(s)

•  jaw_opening.jpg (103.05K)
  Number of downloads: 35

[liftmech]

The guide rod axle. This takes the force of the springs and transmits it to the mobile jaw.

Attached File(s)

•  guide_rod_axle.jpg (87.21K)
  Number of downloads: 33

[liftmech]

Before sending the grip back out, we make certain we've tightened every nut and bolt, greased every moving part, and written the chair number on the traction plate. If we're inspired, we'll also add an instructive message.

Attached File(s)

•  obligatory_message.jpg (89.66K)
  Number of downloads: 49

[liftmech]

So there you have it. There are quite a few things I didn't take photos of, but it would have taken up several pages worth... :D

[KZ]

very cool. How many people does it take to get the job done, and how long does it take?

[liftmech]

Total time- approximately three and a half hours. That's for two people, and includes taking the grip from the flyer to the Eagle. If I get an early start on it, I can have the chair back on line by about two o' clock.

[KZ]

Thats not too bad to completly fix up the grip.

[Kelly]

Lift Mech and Allan:
I have a few questions about your detachable grip inspections that your state requires and most good lift maintenance programs would perform regardless of those requirements.
Would it be safe to assume that you have to inspect and NDT 20% of the total amount of grips on a lift a year?
Would it be safe to assume you also inspect another 5% more on each lift due to various precautionary reasons?
So on a lift with 100 carriers you would inspect approximately 25 per year with a 100% rotation in 5 or less years?
Would this take about 7 man hours a carrier or about 150 to 180 man hours total time per detachable lift for this one group of components?

Thanks for any answers,

Ryan B

[Allan]

We must ND Test 20% grips/carriers annually. We ND Test 100% of the Thiokol carriers, but 20% of the grips. We inspect all the carriers, but don't ND Test them all. All the carriers MUST be inspected within five years. It's not a random system either... Year 1 we inspect chairs ending with 0 & 5 (5, 10, 15, 20, etc) and year two is 1 and 6... and on like that. I haven't been involved with much ND testing - as inter mtn testing does most of it for us. This is for FG lifts... we have no detachables :)

[liftmech]

CPTSB mandates a 20% per year NDT rotation on all grips, fixed or detachable, which makes it a 100% every five years. You are allowed the option of testing 100% in the fifth year, but due to obvious time considerations, only very small lifts are done that way. Poma mandates an additional 5% test group overy year- the difference between that and the 20% group being that on the 20%, one only NDTs the critical parts of the grip while on the 5% one NDTs everything. Poma further states that 10% of the hanger arms be NDTd every year. These percentages mean that out of 203 cariers, I NDT 21 hangers, do a 'minor' inspection on 41 grips, and completely tear down and NDT 11. In other words, I spend the majority of my winter doing this- between teardown, testing, and rebuilding a 20% grip, it takes until noon starting at eight-thirty. I haven't gotten to the 5% group yet; that will take considerably longer. The seven man-hours a carrier Ryan mentions is about average for this 20% group., plus transporting the grip across the hill and back.

[liftmech]

Cameron requested a shot of a completely disassembled TB grip. Here it is:

Attached File(s)

•  grip_disassembled.jpg (127.08K)
  Number of downloads: 21

[SkiBachelor]

Thanks John, I hope to have that picture on the site soon, i hope.