cylinder safety stops for *bucket* cylinders

[orangetree]

I have cylinder stops (these; same function as u-channel designs of varying polish), which I bought for when I needed to be working under the arms.

I need to use my forks to hold a work platform. I can tie in, so with the FEL arms safe, the "worst" that could happen is a complete hydraulic failure and the platform would go from horizontal to "dumped" and I'd be hanging. No where near as bad as getting crushed outright - but still not good.

Does anyone sell, or have a clean example they fab'd / DIY'd, for safety stops for the BUCKET cylinders? The complication is they raise by retracting, the opposite of the main cylinders which can be held "up" with a simple spacer.

 

[Too many Kubotas]

Two straps or chains?

 

[5030]

How about 2 pair of high pressure WOG valves, two on each bucket cylinder? Open, the curl function would operate normally and closed they would effectively lock the cylinders.

 

[Sportsman762]

Does anyone sell, or have a clean example they fab'd / DIY'd, for safety stops for the BUCKET cylinders? The complication is they raise by retracting, the opposite of the main cylinders which can be held "up" with a simple spacer.

Remove the bucket. If its not up in the air then it cannot fall. I cannot think of any reason to increase risk by leaving the bucket on when working under it.

Tow straps or chains?

I have used chains on loaders that did not have a quick attach bucket.

 

[orangetree]

How about 2 pair of high pressure WOG valves, two on each bucket cylinder? Open, the curl function would operate normally and closed they would effectively lock the cylinders.

Interesting idea. I don't like the thought of putting more moving parts there, but this would seem to be "pretty close" to the safety provided by the arm cylinder lockout bars.

 

[orangetree]

Remove the bucket. If its not up in the air then it cannot fall. I cannot think of any reason to increase risk by leaving the bucket on when working under it.

I have used chains on loaders that did not have a quick attach bucket.

See the OP. The bucket (specifically) is already off, I'm talking about a work platform on forks. And I'm on it, not under it.

 

[orangetree]

Two straps or chains?

Did you bolt or weld on something to the FEL arms for an attachment? I suppose that would probably work.

Keep in mind use-case here is a bit different than the main arm cylinders - for those, in general, you're preventing the arm from falling "a lot" and crushing you.

On a work platform a "drop" of ten's of degrees could still be serious, as the platform would move violently while you're relying on it to be stable. With a "strong" anchor, I could see using a ~load-binder to tighten the chain you mention - which would prevent any significant movement of the bucket joint.

Point being this would it seems to require some sort of custom mount point welded to the FEL, in order to be tightened to remove any slack (?) On the main arms, I'd be doing the equivalent - gently setting it down onto the safety plates (or rather, after a half hour it would settle there, anyway)

 

[Sportsman762]

See the OP. The bucket (specifically) is already off, I'm talking about a work platform on forks. And I'm on it, not under it.

I missed that in the original post.

A chain would work, but it does not let you adjust the angle when raising it. There is no simple answer to this that will meet your requirements involving stops that I am seeing. The simplest solution would be to put three or 4 legs on the work platform and lower them once the platform is at height. The platform is then not affected by any hydraulic drift.

 

[Too many Kubotas]

Did you bolt or weld on something to the FEL arms for an attachment? I suppose that would probably work.

Point being this would it seems to require some sort of custom mount point welded to the FEL, in order to be tightened to remove any slack (?)

I've never worried about hydraulic failures when working on things while standing in the bucket or on a pallet (on pallet forks), so I haven't looked for suitable anchor points.

I'll check tomorrow, but seriously doubt that there aren't already useable places to hook straps or chains to...without having to weld anything extra onto the loader.

 

[Smokeydog]

Wanted to test an idea and made these adjustable safety stands. Tested with 600# weight plus me with complete relief of pressure. One can support the load but a little bouncy. Admittedly don’t always use them but nice option depending on the job.

 

[Sportsman762]

@Smokeydog I could not remember who made a platform with legs. That is some nice work you did!

 

[orangetree]

My mechanics-of-materials is screaming BUCKLING BUCKLING! Just giving you a hard time. A great safety feature.

But since we're talking safety - I can't not add here don't rely on that for anything beyond a true backup. While you didn't state tube specs, it's likely a fine safety factor in compression only - but it's buckling that'd be the failure mode for sure, and this could develop very quickly. Also any torque on the structure would exacerbate it.

I point out the above because my FEL sags quickly enough (an inch per hour maybe?) that it would load the "safety" structure. Granted you'd still have to have a hydraulic failure to experience a full fall; but again we're talking redundant systems here and if the FEL were to relax onto to posts, followed by post buckling, you could see several inches of ~free fall. Plenty to send you toppling if it happens at a sub-optimal moment.

 

[Too many Kubotas]

If those legs would be able to buckle, the set bolts would've seriously deformed them first.

 

[orangetree]

If those legs would be able to buckle, the set bolts would've seriously deformed them first.

You're correct that any deformation caused by the bolts will dramatically decrease a tube's resistance to buckling (see: a dented pop can). But less so about the tube's behavior in buckling overall.

I'm replying because we're discussing implementing safety features. The actual mechanics of buckling stress are not necessarily intuitive if you've never had to calculate them. Perhaps even then, lol. They are MUCH lower than you'd expect.

If you want to learn more there are tons of better teachers online than I - but I'll just offer one contrived example. Have someone push down on a vertical tent pole. Easy to buckle. Now see how much lateral support is required to prevent them from buckling it. Very low, comparatively. lateral support, even though very small compared to the axial load, makes an outsized difference in buckling of something "high aspect ratio".

 

[Smokeydog]

Not sure of your platform design or lateral loading but maybe you shouldn’t be using a tractor loader? There are many alternatives. The safety legs don’t have to support much lateral load as the loader and tractor are there even with loss of hydraulic pressure. Even if they buckled they would slow descent in catastrophic failure. How they might fail was considered in the design. Survivable? Hope I never find out. 12’ fall I would much rather be in man basket than on a ladder. Don’t bounce as well as I used to.

 

[Too many Kubotas]

Okay, took a quick look at the loader on the M6040 and there are five (per side) places where it'd be easy to run a strap to keep the bucket from curling out.

Only counted places that have favorable geometry. Simplest would be a single strap going around the center of the tube between the loader arms.

 

[scootr]

I made a pair for the MX. Just welded 2 pieces of 2" angle to make a U shape that fits over the bare piston part of the cylinder and fastens in place with a clevis pin.

 

[oldnslo]

Install counterbalance valves hard plumbed directly to the cylinders. This is what is used on boom lifts. Works in all cylinder positions and requires no manual adjustment of locks or supports.

I believe must be set around 25% higher than system pressure to meet safety standard but not positive on than percentage.

 

[orangetree]

I made a pair for the MX. Just welded 2 pieces of 2" angle to make a U shape that fits over the bare piston part of the cylinder and fastens in place with a clevis pin.

As in the OP, I'm talking about the bucket cylinders not the main/arm cylinders. I am already using a block for the arm cylinders.

 

[orangetree]

Install counterbalance valves hard plumbed directly to the cylinders. This is what is used on boom lifts. Works in all cylinder positions and requires no manual adjustment of locks or supports.

I believe must be set around 25% higher than system pressure to meet safety standard but not positive on than percentage.

Thanks. It's looking like these, or some sort of chain attachment, are my options. IDK - I'm sure you're correct about the counterbalance being used in safety situations, but I don't design this sort of equipment / am no hydraulic expert, presently I'd feel a LOT better about something purely mechanical I will do some more research, though.