Hydraulics Piping Questions

[mmranch]

Imagine the steel piping which goes to a simple hydraulic gear pump which has an inlet and an outlet.

The inlet pipe is approximately 1 1/4" in diameter. The outlet pipe is approximately 3/4" in diameter.

The inlet pipe comes from the transmission & filter to the pump. About 2' before the pump, the inlet pipe has a 2" gap in the steel pipe. This gap is joined together with a rubber hose. (This gap is there to provide some flex to the pipe when attaching it to the hydraulic pump).

The outlet pipe comes from the outlet of the pump and goes to the PTO block with hydraulic pressure. This steel pipe is unbroken between the pump and the PTO block.

My question is... would there be any problem with cutting this outlet pipe and joining it back together with a short hose section? Say a 4"- 6" hose section over a break in the pipe of 1"?

Thanks for any ideas!

 

[AWSubie]

As long as you use a hose and couplings rated for the pressure, flow, and temperature of the pump it should suffice.

I saw a spec sheet online that listed the tym 603 hydraulic pressure at 2000 psi.

If I was experimenting with installing a hose I would start out with a braided hose rated at 2500 psi minimum and using at least two t-bolt type band clamps on each end.

 

[mmranch]

Thanks for the ideas!

It sounds like I would need to make the cut ends of the pipes into some sort of flared compression fittings or something (not sure of the proper terminology) so that a hydraulic hose could be attached to each pipe end? (I haven't made compression fittings before).

Thanks again.

 

[ptsg]

You can simply use hydraulic compression fittings, then the hard line goes on one side of the fitting and the hose on the other.

There are these fittings that doesn't need flare. You simply push the hardline on the fitting till it bottoms out and tighten the nut and you're all set up. Don't even need to go too crazy on the torque of the nut.

 

[AWSubie]

I’d be tempted to replace the entire hard line with a hose.

 

[CJONE]

Do NOT use clamps to keep 2500psi of pressure contained!! The bite type fittings that PTSG recommended work fine just retighten after a few heat cycles. go with fnpt or mjic and make a short jumper hose rated for the pressure. CJ

 

[mmranch]

Thanks very much to all for this hydraulic fitting info! I will look into what I need to do this.

Thanks again.

 

[WranglerX]

Keep in mind the pressure, it could be up to 2500PSI... I would replace pipe with exact replacement part or a high pressure hose with proper connector/fitting on it, patching it with something as simple as putting in a section of hose and a few hose clamps is going to be a disaster ... Also keep in mind inlet to pump is probably a suction line there for not requiring high pressure pipe/hose....

EDIT TO ADD:.... Don't see any reason or need to cut outlet pipe if undamaged... You need to better explain why you would want to do this....

 

[LD1]

You cannot just use hose and clamps on high pressure hydraulics.

Hose fittings need crimped, and tubing either needs flared, brazed/welded, or a compression/swagelock fitting.

Pictures would be worth a thousand words

 

[Harry in Ky]

Imagine the steel piping which goes to a simple hydraulic gear pump which has an inlet and an outlet.

The inlet pipe is approximately 1 1/4" in diameter. The outlet pipe is approximately 3/4" in diameter.

The inlet pipe comes from the transmission & filter to the pump. About 2' before the pump, the inlet pipe has a 2" gap in the steel pipe. This gap is joined together with a rubber hose. (This gap is there to provide some flex to the pipe when attaching it to the hydraulic pump).

The outlet pipe comes from the outlet of the pump and goes to the PTO block with hydraulic pressure. This steel pipe is unbroken between the pump and the PTO block.

My question is... would there be any problem with cutting this outlet pipe and joining it back together with a short hose section? Say a 4"- 6" hose section over a break in the pipe of 1"?

Thanks for any ideas!

I can't help but ask why do you feel the need to do this? Is there damage to the tube?

 

[mmranch]

Thanks again to all for the ideas!

It's a very long story... there is no damage to the outlet tube.

My tractor has certain hydraulic gear pumps and plumbing. The gear pumps are very rare and specialized. The main gear pump has failed. Getting replacement pumps has been impossible so far. After searching the world over (literally), I have finally found gear pumps (for a different tractor) which basically match my rare and specialized pumps and will mate with my engine.

Even though these 'other' pumps will work with my system... the pumps have different type flanges for the inlet and outlet. My current piping flanges will not connect. So in addition to purchasing the 'other' pumps... I must also purchase the 'other' piping with flanges. I must cut the pipe to add fittings and a hose so that the 'other' pump will integrate with my current hydraulic system.

Thanks again.

 

[rScotty]

In your situation I would be tempted to buy threaded adapters to get from the pump to a standard hose fitting. But of course with the adapters taking up space then the pipes no longer fit. A way to deal with that is to replace the pipes with hoses. Since you would only have two hoses to the pump, that may be your solution.
rScotty

 

[rScotty]

Imagine the steel piping which goes to a simple hydraulic gear pump which has an inlet and an outlet.

The inlet pipe is approximately 1 1/4" in diameter. The outlet pipe is approximately 3/4" in diameter.

The inlet pipe comes from the transmission & filter to the pump. About 2' before the pump, the inlet pipe has a 2" gap in the steel pipe. This gap is joined together with a rubber hose. (This gap is there to provide some flex to the pipe when attaching it to the hydraulic pump).

The outlet pipe comes from the outlet of the pump and goes to the PTO block with hydraulic pressure. This steel pipe is unbroken between the pump and the PTO block.

My question is... would there be any problem with cutting this outlet pipe and joining it back together with a short hose section? Say a 4"- 6" hose section over a break in the pipe of 1"?

Thanks for any ideas!

I just saw your yesterday's message.
You can break the inlet pipe that way and add a hose. You CANNOT and MUST NOT break the outlet pipe that way and add a hose unless you put special fittings on the pipe and the hose. More trouble than it is worth.
Just go with a hose all the way on the outlet. Get a hydraulic hose made up to fit. Locally source is fine.
rScotty

 

[Harry in Ky]

I don't know if I agree with all that. I've been cutting hydraulic tubing such as this and doing custom work on them for years. I've had no problems from it. You don't know what his new pump is, what style/size ports it has, or anything else about it. No need to dictate what he can or can't do.

Should he offer those specifics and then asks for advice, you're free to make your case.

 

[Fxfymn413]

Another alternative is to have the pipe welded by a certified welder. The welder could even sleeve the joint for additional strength.

 

[rScotty]

I don't know if I agree with all that. I've been cutting hydraulic tubing such as this and doing custom work on them for years. I've had no problems from it. You don't know what his new pump is, what style/size ports it has, or anything else about it. No need to dictate what he can or can't do.

Should he offer those specifics and then asks for advice, you're free to make your case.

OK then Harry. We've got two guys giving opposite advice. I don't have a problem with that. The Original Poster can decide who to believe & which way to go.

The question he originally asked was, "My question is... would there be any problem with cutting this outlet pipe and joining it back together with a short hose section? Say a 4"- 6" hose section over a break in the pipe of 1"?

You say you have been cutting hydaulic tubing such as that and doing custom work for years and what he is asking is OK. You say you've "done this for years".

I say it is NOT OK. THis is 2000 psi or more. It is dangerous pressure and he should not in any way attempt to cut a high pressure line and then bridge the gap with a rubber hose like he has on the low pressure side. Just because it works on the low pressure (suction side) has no bearing on it being able to work on the high pressure side. High pressure hydraulic leaks are not something to fool with

So now the owner can decide which way he wants to go.
rScotty

 

[LD1]

Using a 4-6" piece of hose between two high pressure pipes is not the issue. And yes it can be done.

The issue is the hose type and fitting type.

Adapt to a common hydraulic thread (JIC, NPT, ORFS), or flare the tube, or use a swageloc fitting....all okay to "join" the pipe sections.

Simply slipping a hose section over and using clamps.....NOPE. NOT for the high pressure side

 

[mmranch]

Thanks to all for the ideas and opinions... I really appreciate it.

If I do have to go this route... I will be using some form of the proper high-pressure fittings, hoses, etc. to make the high-pressure line.

Magically... the solstice seems to have brought some movement on the issue as the new gear pumps I ordered previously have appeared at my dealer and are on the way to me now. I may not have to integrate the 'other' pumps at this time. But it's nice to know there are options for going a different route if need be.

Thanks again.