CAT/JLG telehandlers use lock valves on the Butt end not the blind or rod end. The blind end does tie into the valve to pilot it open during operation.
That said, the only way the boom retracts is if the cylinder and not the hose fails. The original post is correct in that. What they overlooked is that the cylinder is fed by both retract and extend hoses on the butt end and then are hard plumbed to each side of the cylinder. Where these tube's weld on can get a pinhole from physical damage and fail in the manner seen in the video. That would be the only way it makes sense.
I am a current engineer staring at the Schematic on my screen.
It may have been punctured with a bullet. I use the machines and know they have redundant safety mechanisms to reduce the probability of death. I've never seen them spray like that when a hose breaks
The weight of the boom at that angle would load the circuit. When a hose breaks it is usually a gush of fluid. A pinhole to the cylinder/fitting makes the spray. I have seen defective cylinders do this exact thing in field tests. It is almost always in the tubing welds on the cylinder.
Edit: also the lock valve is built into the butt of the cylinder. So hose failures would only leak fluid trapped in them. It would have to be cylinder damage to both allow the boom to fall, and have pressure enough to spray.
I don't believe so because I do not believe even a .308 would penetrate a medium pressure cylinder of that size. The spray was more like a pinhole was caused from a strike on the tube or weld.
CAT/JLG telehandlers use lock valves on the Butt end not the blind or rod end. The blind end does tie into the valve to pilot it open during operation.
That said, the only way the boom retracts is if the cylinder and not the hose fails. The original post is correct in that. What they overlooked is that the cylinder is fed by both retract and extend hoses on the butt end and then are hard plumbed to each side of the cylinder. Where these tube's weld on can get a pinhole from physical damage and fail in the manner seen in the video. That would be the only way it makes sense.
I am a current engineer staring at the Schematic on my screen.
It may have been punctured with a bullet. I use the machines and know they have redundant safety mechanisms to reduce the probability of death. I've never seen them spray like that when a hose breaks
The weight of the boom at that angle would load the circuit. When a hose breaks it is usually a gush of fluid. A pinhole to the cylinder/fitting makes the spray. I have seen defective cylinders do this exact thing in field tests. It is almost always in the tubing welds on the cylinder.
Edit: also the lock valve is built into the butt of the cylinder. So hose failures would only leak fluid trapped in them. It would have to be cylinder damage to both allow the boom to fall, and have pressure enough to spray.
No argument there. I only have field use experience regarding this type of equipment
Would that verify the type of round as well, which would be .22 or .223/5.56? Any other caliber would make a larger hole than that.
I don't believe so because I do not believe even a .308 would penetrate a medium pressure cylinder of that size. The spray was more like a pinhole was caused from a strike on the tube or weld.