Thread: Any one know about hydraulics?

Hi Rusty, I know nothing about hydraulics, what I am suggesting is that you place this in the metalwork section, as there might be someone who doesn't come that knows these things.
Kryn

Only a "T" piece is required, the other valves that you have seen on loaders might have been load check valves for added safety. These require pressure to be applied before they release, so if a hose bursts the bucket or arms will not drop unexpectedly. These are usually plumbed in with hard lines for maximum safety.
My Husky skid steer uses only "T" pieces.

Cheers Kryn - will do.

Originally Posted by Karl Robbers

Only a "T" piece is required, the other valves that you have seen on loaders might have been load check valves for added safety. These require pressure to be applied before they release, so if a hose bursts the bucket or arms will not drop unexpectedly. These are usually plumbed in with hard lines for maximum safety.
My Husky skid steer uses only "T" pieces.

The safety thing would make sense. I should have a closer look at the block on my Burder (Australian) loader to see what it does - it definitely looks to have relief valves of some sort.

Good to know a straight tee piece is used on other machines.

A tee piece is the go shouldn't be a problem worked on my homemade tractors front loader

Not 100% sure on exact legalities, but I know that workplace regs now require log loaders to have twin top clamps on circuits individually protected by load check valves and loaders that have either EWP's or Jibs attached require them on both the lift and crowd circuits. In your case, what's the worst that could happen if a line blows? You drop a load of dirt or rocks on the ground. No load check on the 3PL anyway.
Could you get away with just one central cylinder to keep costs down? Quite a few Bobcats had only one central crowd cylinder by the way. Yet another option with multiple benefits would be a hydraulic top link, this may even give the desired range of crowd without fitting extra cylinders to the implement. I have a hydraulic top link on my tractor and wouldn't part with it for the world.

Originally Posted by Karl Robbers

Not 100% sure on exact legalities, but I know that workplace regs now require log loaders to have twin top clamps on circuits individually protected by load check valves and loaders that have either EWP's or Jibs attached require them on both the lift and crowd circuits. In your case, what's the worst that could happen if a line blows? You drop a load of dirt or rocks on the ground. No load check on the 3PL anyway.
Could you get away with just one central cylinder to keep costs down? Quite a few Bobcats had only one central crowd cylinder by the way. Yet another option with multiple benefits would be a hydraulic top link, this may even give the desired range of crowd without fitting extra cylinders to the implement. I have a hydraulic top link on my tractor and wouldn't part with it for the world.

The bucket letting go isn't a big concern - it'll already do that now if you're on bumpy terrain with a heavy load - I think the latch is a bit worn.

My first thought (after I worked out hydraulically actuating the latch would be too hard) was a single cylinder, but it would need a very long stroke to tip the bucket enough to dump, and there's no room for such a big cylinder. That lead me to the idea of putting one each side (much closer to the pivot axis), where I'd only need an 8" stroke.

We already have a hydraulic top link, hence the dodgy-looking mod to the top of the implement, as the cylinder is a bit longer than ideal. It does help quite a lot, but there isn't enough stroke to be able to dump just using it.

It would be relatively easy to make a scissor action lever that allows for a shorter cylinder to actuate a longer stroke. Particularly considering that you don't need much force at all.