Anyone use black pipe on their tractors ?

[Villengineer]

First, "Black iron pipe" isn't iron, it's steel. But that's just a FYI.

The answer to initial question is that it depends upon the type of construction, diameter, and schedule.

The problem with the pipe you get at the local hardware or big box store is that it's normally low schedule WELDED pipe and cheap low schedule cast steel fittings. It was never intended to be used in a hydraulic system. Never used galvanized, if for no other reason than it can flake and contaminate your system.

SEAMLESS steel pipe and the correct fittings are still used in stationary hydraulic systems all the time, you just have to have the right size and schedule for the operating pressure. However, it is primarily limited to larger diameters where hydraulic tubing and/or fittings aren't available or aren't cost effective.

You don't see it used on mobile equipment any more for three primary reasons:

1) NPT threads are very susceptible to loosening due to vibration, which = leaks. That's why the o-ring sealed fittings have become the standard in the hydraulic industry.

2) More difficult to design and manufacture using it. You can't reasonably bend it, thus more fittings which = more potential leaks. Plus, the limitation of the fittings make it more difficult to route the lines. Cutting, threading, size, weight, etc... you get the idea.

3) The smaller diameters (very common in mobile systems) are a limitation on the working pressure.

Basically, if you have the right material it is just as safe, but is more likely to leak. Outside of working with older equipment where it was used originally, I just don't know why you'd want to use it as the correct material isn't any easier for the average guy to get than hydraulic tubing and fittings.

 

[kevinj]

Okay, I know that a lot of guys are going to write in and say that they use it with no issues, However, black iron pipe is rated for 350 psi. You might get some up to 500 psi. Now there is a 4:1 burst factor, so it will go to a minimum of 1400psi before it blows. It is very dirty inside and is a time bomb waiting for the minute hand to hit the right spot. If you look at an iron pipe fitting and a standard hydraulic fitting side by side, you will see the difference.

There are black pipe & fittings for 3000psi used for hydraulics and steam. We have piped several hydraulic systems for customers with this heavy welded piping.

 

[SPYDERLK]

There are black pipe & fittings for 3000psi used for hydraulics and steam. We have piped several hydraulic systems for customers with this heavy welded piping.

Often when a control valve is centered the relief valve is isolated from the load. In such cases, if the load changes the hyd pressure does too. A bounce of a loader causes very high pressure spikes because the fluid is not compressible. Applications with steam would be a little "softer".
larry

 

[Wayne County Hose]

There are black pipe & fittings for 3000psi used for hydraulics and steam. We have piped several hydraulic systems for customers with this heavy welded piping.

This is definately not the stuff the originator of this thread was referring to.

 

[Villengineer]

??????? I see tubing of all sizes on modern equipment, especially -6 and smaller. Tubing is cheaper than hose and when given the choice, manufacturers almost always use hard lines instead of hose.

I think you misunderstood what I was saying. On stationary equipment it's not uncommon to see lines larger than 1" in pipe and less than 1" in tubing. Once you get above 1" the tube fittings start getting real expensive. -4, -6, and -8 are all very common and therefore relatively cheap.

And at least in the OEM setting, currently, tubing is not always cheaper. In the current market, old rules of thumb like that aren't always true.

?????? I still see more JIC than any other fitting. If given the choice, I would use British Pipe exclusively as it is by far (in my opinion) the best, most versatile fitting in production.[/QUOTE]

JIC is still very common for hose and tube connections to other fittings. SAE O-ring is probably by far the most common connection to pumps, valves, manifolds, etc..

There is a very big push to replace JIC with systems such as O-ring face seals and also with fittings which use elastomers instead of flares to seal the tube to the fitting. Leaks are now viewed as far more than just an annoyance.

 

[kevinj]

This is definately not the stuff the originator of this thread was referring to.

You are correct about the poster but you stated something about pipe available up to 450#. I just wanted to clarify that that the proper material is available if they do not want tube or hose.

 

[kevinj]

Often when a control valve is centered the relief valve is isolated from the load. In such cases, if the load changes the hyd pressure does too. A bounce of a loader causes very high pressure spikes because the fluid is not compressible. Applications with steam would be a little "softer".
larry

You are correct about fluid compression but steam which picks up a slug of water hurls a non compressible mass down the pipe. We can get the steel pipe and forged fittings to about 9000# or so if I remember right.

 

[dfkrug]

First, "Black iron pipe" isn't iron, it's steel. But that's just a FYI.

You beat me to it, VILLENG.

Also, most of the castings we have on our tractors are cast Al or cast steel.
True cast iron is not generally used. The cast steel I run into is also fairly
soft....significantly softer than say plow steel.

As for pipe fittings, gas plumbers usually prefer black cast steel over galv
cast steel cuz the latter can leave zinc flakes in your system. You also hit
on that one.

 

[Wayne County Hose]

??????? I see tubing of all sizes on modern equipment, especially -6 and smaller. Tubing is cheaper than hose and when given the choice, manufacturers almost always use hard lines instead of hose.

I think you misunderstood what I was saying. On stationary equipment it's not uncommon to see lines larger than 1" in pipe and less than 1" in tubing. Once you get above 1" the tube fittings start getting real expensive. -4, -6, and -8 are all very common and therefore relatively cheap.

And at least in the OEM setting, currently, tubing is not always cheaper. In the current market, old rules of thumb like that aren't always true.

?????? I still see more JIC than any other fitting. If given the choice, I would use British Pipe exclusively as it is by far (in my opinion) the best, most versatile fitting in production.

JIC is still very common for hose and tube connections to other fittings. SAE O-ring is probably by far the most common connection to pumps, valves, manifolds, etc..

There is a very big push to replace JIC with systems such as O-ring face seals and also with fittings which use elastomers instead of flares to seal the tube to the fitting. Leaks are now viewed as far more than just an annoyance.

Yep, I did misunderstand you. You are correct.
I know it's not "iron", but that's what it's been called since the earth cooled.
I can see that JIC is on the way out, as it should be. To me, NPT is ancient, JIC a little better, but flat face o-ring is much better than JIC. SAE o-ring is most common in ports, valves, and pumps not because it's any better than JIC, but because of machining cost. NPT is also very rough on aluminum manifolds. When they developed ORB, they patterned it closely to JIC by using the same thread sizes. But, all things being equal, I will still take BSPP anytime. It's the only fitting you can use for ports and hoses.
There is also a big push on the O-ring version of JIC. It is a small o-ring boss machined onto the male end, then an o-ring installed. It is supposed to fill in minor imperfections in the seal surface. The only thing I have seen it do is have my customers calling me asking what the heck it is and if I have o-rings for it as they fell out when disassembled.

 

[nightrodjc]

Wow, I was looking for a simple NO...