|
|
Eastern Oregon | I understand that stainless or black steel are preferred for hydraulic applications. Is there a good reason why you should not use galvanized? I've gotten away with it on a couple of my implements with no obvious problems?
Doesw the oil or higher pressure cause the galvanized coating to flake? Can't say that I have seen it happen, but then I have never actually looked for it. |
|
| |
|
NW Montana | why risk it? one flake in the wrong place will be a B...ch. Pumps cylinders, motors are a lot more than a fitting. |
|
| |
|
NCIA | What are most hydraulic fittings and hose ends made of? I always assumed they were some sort of galvanizing. Maybe I'm missing something here I dont see the concern on the flaking issue. Maybe on cheap galv pipe. |
|
| |
|
northern Mi | Galvanized pipe is not strong enough for hydrologic pressures. It might work in certain applications,possibly only temporarily,but it isn't safe or logical.doesn't cost much more to do it right. |
|
| |
|
Sac & Story county IA | We have all used them and gotten along, mostly. But the rating for plain pipe fittings is 150 psi. |
|
| |
|
| Galvanized pipe and fittings are normally considered to be water piping. Not many water systems running at 2500 psi. Schedule 80 fittings and piping are normally only black and stainless I believe. |
|
| |
|
Columbia Basin, Ephrata, WA | I've been told that there is a risk of the galvanizing flaking and running the zinc through all of the high $$ parts. Schedule 40 is best only used on the suction and low pressure return lines. If used on the suction and it flakes, it'll mess up every componenent in the system downstream, so I guess if you have to use a galvanized fitting, try to put it just ahead of the filter.
Edited by Big Ben 2/23/2015 20:37
|
|
| |
|
| Galvanized fittings are rated for a maximum of 150 psi or less. I've seen them break at natural gas pressure close to the furnace and with building water pressure, probably from being overtightened on the tapered threads. Hydraulic systems run 1800 to 2500 and sometimes greater pressure and take forged steel fittings to actually be rated at that pressure. The hazard with the ordinary galvanized fitting is being hit by pieces of it when it breaks or by a jet of oil when it just cracks a little. I've seen them used but I won't power up equipment plumbed that way.
Gerald J. |
|
| |
|
NW Washington | The main issue with galvanized pipe or fitting in a hydraulic plumbing is the possibility of zinc flakes making it into the hydraulic fluid and causing problems.
Using schedule 40 or 80 pipe as hydraulic lines is generally not a good idea, especially with newer tractors and higher working pressures.
Here is the working pressure and burst pressure for schedule 40 carbon steel pipe. http://www.kalhour.ae/downloads/psi_chart_as_per_pipe_wt.pdf |
|
| |
|
Dallas Center IA 515-720-2463 | N P T is AGAINST the LAW
NPT is very poor for hydraulic systems - PERIOD.
#1- It leaks
#2- Hard to do a good job of putting it together.
#3- Along with assembly, it seems to require more space.
#4- Even harder to get the stuff apart.
My favorite is JIC, followed by SAE O-ring. There are others.
The only time I will use NPT is a NPT to JIC or NPT to SAE adapter.
Any NPT ends hydraulic hose that needs to come apart, goes to the storage area. Which means it will probably be thrown away.
JIC, SAE, etc assemble easy, using end wrenches, vs pipe wrenches for much NPT. Does not require tape or paste. About all female fittings are swivel.
JIC, SAE, etc will come apart very easy. Common end wrenches. No end wrench spreading on NPT hex fittings. No need for the big hard to use pipe wrenches when the end wrench fails.
Myself, if I get into something with NPT in it - I throw the stuff away. Not worth fooling with.
The reason so many farmers use NPT is hardware and farm stores carry it.
Do yourself a favor, go to your equipment dealer or a hydraulic supplier and get CORRECT hydraulic fittings.
For the OP's question: Black pipe is a lot better than galvanized. Strength and the flaking.
|
|
| |
|
Leeds, North Dakota | Galvanized is a NO-NO, schedule 80 steel pipe in a bind, agree with Bobby, years ago when we didn't have hydraulic pressure like we due now npt was the standard, Jic is not used much, Orb, and flat face are standard now, Scott. |
|
| |
|
Wi | They are forged carbon steel fittings that are electroplated. Often times with zinc or a caring containing zinc. Nickel is also used along with other coatings. There's also stainless fittings too of course.
The low pressure galvanized plumbing fittings are often hot dipped cast fittings. Much cheaper.
There's also a difference in threads. Most hydraulic fittings use NPTF versus plumbing using NPT. NPTF requires no sealant or tape when used properly, most people cram a bunch in there anyways for some reason. |
|
| |
galvanized fitting on hydraulic?
