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Turning a pelton runner in-between machining operations

KristianSilva

Aluminum
Joined
Nov 26, 2016
Right,

Imagine you have one of these to machine.... (pelton runner)

Machined Runner.jpg

And imagine you are machining it from solid and that after your first roughing operation the part looks like this:

Part Machined Runner.jpg

Now, the question is, how would you rig this part so that you can flip it over to do the same roughing operation on the opposite side?

For reference the part(s) are up to 1.4m (55inch) in diameter and weigh approx 4000Kg (8800lbs).

We have a single hoist 25 ton crane available at the site of the machine, I understand how this lift would be done with a dual hoist crane:

YouTube

YouTube

However with a single hoist crane I'm worried that if we hitched at the circumference of the part and lifted from there we would shock load the crane as the part "tips" in to the vertical position

What do you guys think the best way to turn over this part?

Thanks in advance
 
Thats where experience comes in......work with cranes and hoists for 10 years,and youll know exactly how to turn it without any shock........a newbie is likely to have slings fall off as it flips .
 
Right,

Imagine you have one of these to machine.... (pelton runner)

View attachment 267741

And imagine you are machining it from solid and that after your first roughing operation the part looks like this:

View attachment 267740

Now, the question is, how would you rig this part so that you can flip it over to do the same roughing operation on the opposite side?

For reference the part(s) are up to 1.4m (55inch) in diameter and weigh approx 4000Kg (8800lbs).

We have a single hoist 25 ton crane available at the site of the machine, I understand how this lift would be done with a dual hoist crane:

YouTube

YouTube

However with a single hoist crane I'm worried that if we hitched at the circumference of the part and lifted from there we would shock load the crane as the part "tips" in to the vertical position

What do you guys think the best way to turn over this part?

Thanks in advance

Locomotive wheels, one hook, solution was clever chains and/or ratchet chain come-alongs.

But I din't have anywhere near the challenge as to protecting so many delicate features. Those righting damaged armored vehicles, much the same, so...

Can you bring - say a 12K or better - forklift into the zone as control helper?

Or a rented boom?

You don't do these things all that often, might be faster to find than a Wizard-grade rigger as makes it look easy with a hasty gin pole and cordage!

:)

Lot of coin invested in that part.

Not on a Manager's dance-card to FUBAR it over lack of few hundred bucks worth of short-term auxiliary rigging gear - and hired-in expertise - just because you don't have nor need dual hooks handy all the time.

Might be best to go the extra mile and put a rigger onto the whole task, stand back, watch. Learn.
 
Thats where experience comes in......work with cranes and hoists for 10 years,and youll know exactly how to turn it without any shock........a newbie is likely to have slings fall off as it flips .

Locomotive wheels, one hook, solution was clever chains and/or ratchet chain come-alongs.

But I din't have anywhere near the challenge as to protecting so many delicate features. Those righting damaged armored vehicles, much the same, so...

Can you bring - say a 12K or better - forklift into the zone as control helper?

Or a rented boom?

You don't do these things all that often, might be faster to find than a Wizard-grade rigger as makes it look easy with a hasty gin pole and cordage!

:)

Lot of coin invested in that part.

Not on a Manager's dance-card to FUBAR it over lack of few hundred bucks worth of short-term auxiliary rigging gear - and hired-in expertise - just because you don't have nor need dual hooks handy all the time.

Might be best to go the extra mile and put a rigger onto the whole task, stand back, watch. Learn.


I should have said to be clear, I am inexperienced and I am definitely not going to just "give it a go" and hope it will be alright.

The thing is we are actually going to be machining quite a few of these. At the moment we are looking into getting some purpose build lifting equipment made, but I just wanted to see if there was a way this could be done with off the shelf lifting equipment?
 
I should have said to be clear, I am inexperienced and I am definitely not going to just "give it a go" and hope it will be alright.

The thing is we are actually going to be machining quite a few of these. At the moment we are looking into getting some purpose build lifting equipment made, but I just wanted to see if there was a way this could be done with off the shelf lifting equipment?

Mindful of available space? Yes, there is flexible MHE. But shop-fab mought be a better fit, and not even all that costly.

Your crane has the raw LIFT capacity, and plenty of reserve. What I'd look to have fabbed is a bespoke clamp-on frame to suspend FROM it that could grasp the part "just so", then once into a clear area, no risk to the machine-tool - rotate it as well, thence back to the table and release.

Safety should be improved, cycle time should be shorter than Monkey-motion, however expert.

Practice on BLANKS -before machining - of course!

:)
 
I should have said to be clear, I am inexperienced and I am definitely not going to just "give it a go" and hope it will be alright.

The thing is we are actually going to be machining quite a few of these. At the moment we are looking into getting some purpose build lifting equipment made, but I just wanted to see if there was a way this could be done with off the shelf lifting equipment?

You need to BUY some experience, not asking for freebies on an internet forum.

If you follow some ones advice here and drop it...doo they care ? No.
 
Mindful of available space? Yes, there is flexible MHE. But shop-fab mought be a better fit, and not even all that costly.

Your crane has the raw LIFT capacity, and plenty of reserve. What I'd look to have fabbed is a bespoke clamp-on frame to suspend FROM it that could grasp the part "just so", then once into a clear area, no risk to the machine-tool - rotate it as well, thence back to the table and release.

Safety should be improved, cycle time should be shorter than Monkey-motion, however expert.

Practice on BLANKS -before machining - of course!

:)

Absolutley will be testing on blanks to begin with, and as far away from the machine tool as possible!!! What does MHE stand for?

You need to BUY some experience, not asking for freebies on an internet forum.

If you follow some ones advice here and drop it...doo they care ? No.


We are buying experience, we have a company looking at it at the moment and we are drafting a design with them, should be a similar concept to these a geared crane ladle essentially:

Geared Crane Ladles - Acetarc: Foundry and Project Engineers
 
Why is it being made from solid? The normal way is each bucket is cast and machined by itself then bolted to the wheel. At least that was true 150 years ago. Makes it easy to replace worn buckets.
Bill D
 
I agree with BillD that it seems crazy to machine from solid...wear parts should be replaceable on the durable hub.

But if you have to make it as shown, I am with Thermite that I would make a lifting girdle with trunnions, and worm-geared handwheel, like a ladle or a concrete mixer

A barrel-dumping attachment for a forklift would not be heavy enough, but a similar design might work
 
Most pelton wheels are one piece these days, at least the new-build ones I've seen. The plant I've been to has them cast to near-net (+1/4" or so) but it took a lot of working with the foundry to get that tolerance from a big multi-part wood master.
 
Large “U” shaped tongs that slip into grooved feature on edge of part. The tong has a shaft off the bottom the U that sits in a pair of bearings that are fixtured to a forklift. So you drive up to the part, spear the edges with the tongs, lift the part a bit more that it’s radius, then rotate the part to other side up. Three simple moves: Lift. Rotate. Set down. Non of this hoisting, slings, worrying your gonna drop something, worrying the things gonna flop or have to sit on a just machined feature. probably build the tongs in a few hours to handle this safely.

Kinda like this, but custom for your part: Rotator Forklift Attachments | ProLift Toyota Material Handling
 
I agree with BillD that it seems crazy to machine from solid...wear parts should be replaceable on the durable hub.
"Wear", as from suspended abrasive fines & such is generally as even as can be, one bucket to the next.

DAMAGE from something that got past an intake grate is what wants one bucket replaceable independently of the others.

Perhaps someone got a rush of "brains to the budget", present-day costs, and simply made sure the inflow is more consistently free of such insults!

:)
But if you have to make it as shown, I am with Thermite that I would make a lifting girdle with trunnions, and worm-geared handwheel, like a ladle or a concrete mixer
Disclosure. A Girl-friend's Dad was founder and CEO of a firm that made ... ta da.. furnace ladles for the steel industry. You'd have to know Pittsburgh, back when they still made steel there. Sure as hell we talked technology over a Sunday dinner. Not whether his only Daughter was any good in the sack!
:)
A barrel-dumping attachment for a forklift would not be heavy enough, but a similar design might work

The crane "should" need less approach space, but then again the cradle has to also clear the machine-tool from the vertical, pick, aside to clear space, flip, return, place.

The FL can approach from any side within a wide arc, DEPENDING on obstructions only at floor-level, pick, aside into clear space, flip, return, place.

Crane already exists. FL "probably", but is it the right size, and which has the more trusted operator & skillset?

Fixture CAN be designed to work with EITHER crane or FL. It certainly should be.

The finished goods have to go off for crating for shipment, too, etc.
 
It seems to me (prefaced by that I know nothing, and don't ever take my advice) it would be simplest to machine a two piece clamp that fits into the grove around the center of the part. Then simply have two trunnion mounts 180deg apart, and located top to bottom at exact COG. Basically the bucket dumping configuration but much simpler. Foundry ladles and concrete mixers and such have an always changing COG and weight when dumping, but on a load that will not change mid flip there is no need for the gear reduction to hold it in position as long as the clamp was properly balanced when designed..
 
Could the design be modified to include 3 tapped holes, equally spaced in the groove on the periphery? I visualize 3 lifting rings installed. Use a 3 leg sling to handle the part on and off the machine. Use a single lifting ring to lift and flip the part. That would be done off the machine. Use the 3 leg sling to get the part back on the machne.

Another approach would be bolt on trunions using tapped holes as described above. Use foundry hooks on a sling with a spreader bar. Pick up the part, roll it over, and set it back on the machine.
 








 
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