hydraulic fittings

[Ricaroo]

Has anyone used the quick connect hyd fittings? I am thinking about if I used them when I took the loader off I would have hyd for another attachment (wood Splitter etc.) When not in use I could make up a jumper hose so the touch control would still operate. Any Thoughts


Rick

[allenlook]

Ricaroo,

Are the quick-connects safe?

[Ricaroo]

Allen,

They must be I see them used on new tractors with auxiliary hydraulics. Bobcats use them to change attachments like post hole digger, bucket, jack hammer, forks etc.


Rick

[allenlook]

I've heard some bad things... Hydraulics scare me more than electricity - both are "invisible energy" waiting to bite you...

I think if the fittings aren't completely tightened (and there's no way to tell if they are or not) you can get yourself killed taking off one of those quick connects.

Of course, you can get yourself killed driving your tractor forward onto a trailer, too, instead of backing it on - farm machinery is some dangerous stuff. I guess I'm just leery of the quick stuff when there's X,000 PSI on the other side.

Don't take my word for it, though. I'm sure there's people that use hydraulics every day without getting hurt. I don't use them all that much, and I don't work with electricity all that much, either, so I tend to respect them overmuch when I do have to work with them to make up for my unfamiliarity.

[kinelbor]

I dont think anyone would change quick connect hoses with the engine running so there wouldnt be any pressure on the other side. Right?

[beaconlight]

You shut down and work the controls to releive pressure before connecting or disconnecting. There are rubber plugs used to keep dirt out while disconnected. With open center spools on your controls you place your male and female fittings so that when you remove an implement one tractor hose plugs in to another to complete the hydraulic circuit. KEEP THE ENDS CLEAN. I REPEAT, KEEP THE ENDS KLEAN.
nO THAT MIS SPELLING WAS NOT AN ACCIDENT, IT WAS TO GET YOUR ATTENTION.

bILL

[Rick Prentice]

Hi Rick. I have the quick connects on my set-up and they are safe if you buy the matched set at your local hydraulic shop. The one caution you have to remember is that your set-up is using the cub pump which is always working when the engine is running, so make sure if you ever disconnect the hoses to the bucket set-up, before you start the engine up, to re-connect the ones in line from the cub pump so you're not shutting off the flow. You probably would damage the pump if the engine was started and there was no place for the fluid to circulate. Don't forget a possible shutoff on your resevoir too, or you'll have fluid all over when you dis-connect that hose, if it's higher than the T/C unit. Make sure you study your complete system and don't start anything until you double check your work. I'm sure you've been doing alot of studying. Have fun

Rick

[allenlook]

Searching Google for "hydraulic quick connect", this is at the top of the list of search results... I'll copy it here just so you're aware - they must work OK 99.999% of the time or they wouldn't be in use, but there's that odd chance.

======================

A worker was fatally injured when the female section of a quick-connect hydraulic coupling hit him in the throat while he was unscrewing it from the port of a hydraulic cylinder. Unknown to the worker, the internal check valve in the coupling section had trapped hydraulic pressure behind it, pressure in the order of 10,000 psi. As he was unscrewing the coupling, it reached the point where the threads were unable to withstand the force from the pressurized hydraulic fluid and the coupling became a high velocity projectile.

These quick-connect couplings are designed to have internal check valves in both the male and female sections. When the coupling sections are brought together, projections on the ends of each check valve serve to move the other check valve off its seat, allowing oil to flow in either direction. If the coupling is not tightly made, one or the other of these check valves may not be properly lifted off its seat. Under this circumstance, oil would flow in one direction but not in the other when the pressure is relieved on the feed side. Tests conducted on the fittings have shown that even with no oil leaks this dangerous build up of pressure can occur when the fittings are one (1) turn or less from fully installed.

Hazard - If the connection of a quick-connect coupling is not made completely tight, one of the internal check valves within the coupling may trap hydraulic pressure behind the check valve. The absence of any leaking oil around the coupling is not an indication that the coupling has been made completely tight.

Required Action
Before using a quick-connect coupling:

Ensure that both sections are in good condition.
Ensure that the threads for the locking sleeve are clean, and that there are no restrictions that would prevent the full threading of the locking sleeve onto the male section of the coupling.
Ensure that the quick-connect coupling is made completely tight.
Always assume that there may be pressure behind a fitting.
Avoid the use of fittings with check valves whenever possible. In particular these types of fittings should not be used for stretching punch press tie rods.
Keep your body out of the line of any potential trajectory. Do not bend over or position yourself in front of any fittings being removed from equipment.
Provide a positive means of confirming all pressure is released (gauges or bleed ports) before removing fittings. This is required by The Regulations for Industrial Establishments, O. Reg. 851, sec. 78.
Location and Sectors
These fittings may be found in all sectors including construction, mining and industrial establishments, where hydraulic equipment is used.

[LiL' Red]

Quick couplers are the safest method of connecting and disconnecting hyd hoses and fittings. Rest assured that a Cub is not going to build up that 10,000 psi of pressure, 1500 maybe. Shut the engine off, cycle the valve both directions[ to release pressure both ways] and the couplers will work just fine. Been using them for 50 years now and never a serious problem.