Thread: Where can I buy 1" or 3/4" Galvanised water pipe from?

Originally Posted by Uncle Al

The outer diameter remains constant regardless of wall thickness or schedule. That way all threaded fittings will fit all wall thickness or schedule pipes. If it was as stated, you would need a myriad of fittings depending on the pipe you have.

I would go for 1" gal pipe, but poly pipe might be easier to install. Not sure how the costs would compare.

Alan...

Friend of mine just installed an air system in his mechanical shop... He used 1" poly pipe... Pipe cost $50... poly pipe fittings $200..

Just called into Reece's to check prices...

1" gal pipe is about $70 for a 1.8m length. I thought this was expensive.

Fittings are approx $4 each, which is a lot cheaper than the poly or proper air pipe fittings.

Just need to see about finding a used stock & die(s) and what sort of money that will be before handing over the credit card


Thx
Jon

Originally Posted by ventureoverland

1" gal pipe is about $70 for a 1.8m length. I thought this was expensive.

That is horrendously expensive....

Go to a steel merchant and buy 6.5m lengths... Should be about $30 a length or around that...

Originally Posted by ventureoverland

Just called into Reece's to check prices...
1" gal pipe is about $70 for a 1.8m length. I thought this was expensive.

As RC says try a steel merchant or specialist pipe supplier.

Fittings are approx $4 each, which is a lot cheaper than the poly or proper air pipe fittings.
Just need to see about finding a used stock & die(s) and what sort of money that will be before handing over the credit card

Watch out for used dies as they are usually stuffed. I wouldn't buy a used die unless I could try it out.

I'm not convinced you need 1" pipe.
Larger pipe sizes really only make sense in large workshops where multiple users are involved.

In terms of pressure drop, the pressure loss over 10m of even 1/2" pipe is mot worth worrying about.

EG
At 150 psi inlet, the loss of pressure for a 15 mm (1/2") pipe is 0.06 psi/m so a 10 m long pipe will drop a whopping 0.6 psi.
For a 20 mm diam pipe the pressure loss is 0.015 psi/m
You will lose far more pressure if you use those narrow coiled delivery hoses or constricted adapters at the end of the lines.

The gain in volume from using larger pipe is minimal for a small workshop.
1/2" pipe is around 2L/10 m of pipe
3/4" is 3L/10m
1" is 5L for 10 m
2" is 20L for 10 m

If you want more volume, it is MUCH cheaper to just use 1/2 or 3/4" add then a 20 or 40 L tank from an old compressor somewhere in the line.

The remaining benefit from larger pipe is better water removal but an auxiliary tank will also help with this.

Thanks everyone... This really is a great fountain of knowledge.

I was thinking / looking at the Warragul dies - looks like thats not a great idea! I also hadn't thought about holding the pipe whilst running the die down the pip... Maybe time to switch over to looking at poly pipe!

Bob, thanks for the info re pipe size.

We're doing the plastic thing at the mens shed where we have to do a 42 m loop about 2.2m above the floor and all around the shed.

I don't like the idea of PVC so we are going with proper air pressure poly.
We're also going with the Philmac quick fit fittings - exxy but quick and easy.

One of the cheapest air pressure pipe is something called Blue Line Poly Pressure metric where a 50m coil of 1" costs about $50.
However, this stuff is relatively floppy and expands in the heat so when laid horizontally it droops a little forming dips in the pipe which can trap water do we are only using this for the verticals. If you only have short runs of horizontal and it can be supported by clips and other structures then this might work for you.

For the around the shed loop we are using 1" stiffer Blue Air Pipe which which is about $6/m.

If you can do it, the horizontals should not be level but slope slight downwards to a vertical with a tap a the end that can be opened every now and then to remove water.

Another thing I have learned is for drop downs. Start by orienting T-pieces so that they point upwards and then add a U-turn for the drop down. This reduces the amount of water than drains into the drop downs.

Originally Posted by Uncle Al

The outer diameter remains constant regardless of wall thickness or schedule. That way all threaded fittings will fit all wall thickness or schedule pipes. If it was as stated, you would need a myriad of fittings depending on the pipe.

Sorry Al but I think you might be getting confused with tubing where the OD and wall thickness is specified; pipe is always Nominal Bore and the actual OD differs between the schedules.

The fittings are also made to different schedules and as they are normally joined using tapered threads the female threads are cut to suit the different wall thicknesses; eg an ASME class 1500 union will have a larger and deeper female thread than a class 150. The male threads on the pipes will be cut the same, around 10 full depth threads allowing a full thread engagement of 7 threads. This allows higher class fittings to be used with lower class pipe but not the other way round.

Having spent the last 5 years working in the coal seam gas industry with US and Canadian machinery and systems I now know far more about piping than I ever expected.... or wanted!

Originally Posted by Chief Tiff

Sorry Al but I think you might be getting confused with tubing where the OD and wall thickness is specified; pipe is always Nominal Bore and the actual OD differs between the schedules.

Not on any of the steel pipe we have.. OD remains the same ID changes with wall thickness... Also ID is nearly always much larger then the stated NB... I just tried to fit a 35mm OD bearing into an 1 1/4" pipe (31.75mm) and the pipe ID was closer to 37mm... 1 1/2" pipe is well over 40mm ID..

Steel pipe historically came with colour band identification..

From lightest grade to heaviest grade was green, yellow, blue, red, white.

Blue band pipe is historically water pipe that is threaded... Red is heavier for higher pressures like steam usage.

Yellow is more structural grade, and green if you look at it too hard it will bend...

Exactly what .RC. said
At least in the last 35 years it has. That's why it is called nominal bore due to the bore varying with wall thickness.
OD has always been the same on pipe.
Tube is a different story.

Phil

People should look up pipe charts..... saves a lot of internet misinformation.

I use a fair bit of pipe in different schedules. OD stays the same.

PDW

Hmm, this is embarrassing, my knowledge of pipe clearly isn't what I thought it was. I just looked up the ASME charts for pipe and it clearly shows I was talking out of my bum


My apologies to anyone I've confused or offended; particular Uncle Al.

Air pressure drop is a factor but if you are using air tools it is the air speed that becomes important. As the pipe size gets smaller the air speed rises and because of that rise the air carries more moisture in suspension. I had this pointed out to me when i was looking at what size to use on my system by a professional installer and he suggested 1" minimum to minimise the problem.

Originally Posted by Chief Tiff

Hmm, this is embarrassing, my knowledge of pipe clearly isn't what I thought it was. I just looked up the ASME charts for pipe and it clearly shows I was talking out of my bum


My apologies to anyone I've confused or offended; particular Uncle Al.

I was on holidays when I replied to this thread, and when I read your reply it really made me wonder how I could have stuffed this up. Was just about to go onto the Onesteel site and look at the tables, when I saw all the other posts confirming what I had said. Anyway, apology accepted, and I like the 'booboo' graphic.

Out of interest, I would love a dollar for every metre of pipe I have bought over the last 40 years, particularly in the last 20 or so for an oil refinery where sizes ranges from 20nb up to 600nb or more and up to Sched. 160. Pipes were mostly in 12 metre lengths, and seamless. There was not very much ERW pipe used. Having to use a crane to lift a single elbow puts things in to perspective. Not being a welder, I was always impressed with the welding of fittings using Tig then stick, with the finished weld almost a piece of art.

As for compressors and air lines, the refinery was full of it. I remember scoring 4 hours overtime to create a purchase order for a Demag compressor worth well over a million dollars, and our dopey computer system at the time wouldn't accept values over 1 million dollars, so I ended up finding a typewriter and manually creating the order.

Paid work was good, but shed work is better, but I do miss the characters I worked with and the challenges created by such an interesting work environment.

Alan...