Running workshop air - school me!

[dholdi]

I was planning on using 1" steel, having seen no one else propose steel am I behind the times ?
The factory I did my apprenticeship at was completely piped in steel, although that was nearly 40 years ago.

 

[brightspark]

I was planning on using 1" steel, having seen no one else propose steel am I behind the times ?
The factory I did my apprenticeship at was completely piped in steel, although that was nearly 40 years ago.

great as long as u don't mind paying the price of bits and getting a set of dies to thread it all

 

[8ob]

I like the 1/2" back plate elbows, the 1/2" pcl`s screw straight into them without loads of other bushes, makes for a nice solid mount.

Bob

 

[HughF]

I like the 1/2" back plate elbows, the 1/2" pcl`s screw straight into them without loads of other bushes, makes for a nice solid mount.

Bob

View attachment 246261

yes, they are very good. Screw it to the wall, screw the PCL fitting into it.

 

[waldershelf]

bang a 22mm copper pipe round its good for cooling and good for 90cfm without loss

90cfm I wish.

 

[MetalMonkey]

- - The main line around the workshop which will be about 40/50m will be 1/2" PEX (no not PVC before anyone has a heart attack)

- - The drops will also be 1/2" PEX

- - The fittings will all be PCL XF

Sounds like a sensible set up to me.

I'm totally confused about the threaded fittings and internal bore to suit certain tools, with BSP/NPT 1/4" , 1/2" etc etc.

I suppose my main query is the most fittings i see are actually 1/4" BSP. In theory does this make the flow advantage of running 1/2" pipe around the shop a waste of time? will 1/4" BSP fittings run say a die grinder or DA ? or do i need all 1/2" fittings??

Same with the regulator/drier at the compressor - most of them i see are actually 1/4" BSP fittings - again do i need to find a 1/2" reg to take advantage of my 1/2" supply piping?

Or, am i over thinking it and will 1/4" BSP run everything i require absoutly fine?

I think it will help to think of it in these terms.

The restriction to air flow is a function of the bore size and the length of pipe. If you have a narrow long pipe it is considerably more difficult to move a volume of fluid (air) through it.
It is obvious that a wider bore solves the problem, but what is less obvious is a shorter length also reduces the resistance.
A coupler might be 1/4" but it is only over a very short distance, so while it does act as a restriction it is far less so than say 50m of 1/4" bore pipe.

This is why it is a good idea to have the main long runs in a wider bore so that it doesn't act as a bottle neck. The drops are typically shorter so they can be in a smaller pipe.

So now it becomes a case of practicality and cost.
In an ideal world everything would be run a large bore all the way through, but the price and availability of fittings, regulators and sundries in those sizes might just not be cost effective for the application.
If there is only a marginal performance drop in using a smaller fitting it often makes sense to do so.

Quick connect couplers are typically narrower than the BSP fittings, although the XF ones are much better.

So to answer the question, no it isn't a waste of time to run 1/2 pipe - in fact for my main line I ran 3/4 with 1/2 drops that then either fit straight into the regulators or quick connects or adapt into 1/4 first.
That way any bottlenecks are kept to a minimum. My hoses are 10mm bore which runs most tools adequately including DA and Die grinders, but I have the option of using a short 13mm bore hose with the large impact gun if I feel I need it.

It is also worth giving consideration to the fall on the pipework and drain valves to ensure that water can't collect at low spots.
I've also had good results in creating a cooler out of a zig zag of 22mm copper pipe before feeding in to the air lines which helps condensing the water out of the hot air from compressor.

 

[whm_fab]

Sounds like a sensible set up to me.



I think it will help to think of it in these terms.

The restriction to air flow is a function of the bore size and the length of pipe. If you have a narrow long pipe it is considerably more difficult to move a volume of fluid (air) through it.
It is obvious that a wider bore solves the problem, but what is less obvious is a shorter length also reduces the resistance.
A coupler might be 1/4" but it is only over a very short distance, so while it does act as a restriction it is far less so than say 50m of 1/4" bore pipe.

This is why it is a good idea to have the main long runs in a wider bore so that it doesn't act as a bottle neck. The drops are typically shorter so they can be in a smaller pipe.

So now it becomes a case of practicality and cost.
In an ideal world everything would be run a large bore all the way through, but the price and availability of fittings, regulators and sundries in those sizes might just not be cost effective for the application.
If there is only a marginal performance drop in using a smaller fitting it often makes sense to do so.

Quick connect couplers are typically narrower than the BSP fittings, although the XF ones are much better.

So to answer the question, no it isn't a waste of time to run 1/2 pipe - in fact for my main line I ran 3/4 with 1/2 drops that then either fit straight into the regulators or quick connects or adapt into 1/4 first.
That way any bottlenecks are kept to a minimum. My hoses are 10mm bore which runs most tools adequately including DA and Die grinders, but I have the option of using a short 13mm bore hose with the large impact gun if I feel I need it.

It is also worth giving consideration to the fall on the pipework and drain valves to ensure that water can't collect at low spots.
I've also had good results in creating a cooler out of a zig zag of 22mm copper pipe before feeding in to the air lines which helps condensing the water out of the hot air from compressor.

Thanks a million for your detailed reply , makes perfect sense! Thanks for taking the time to type all of that up, much appreciated!

Taking all this into account, il think now il go with 20mm MDPE for the loop and drops. It's a killer that the fittings are so expensive, as I'm going to need alot of elbows.

@8ob what wall plate type fittings do you use? Plastic or the brass ones?

Thanks everyone

 

[James1979]

I've some photos to upload although 8ob seems to have a similar setup to mine. Its a lot easier to just use the pipe fittings that match the airlines as he has done. It was expensive, although I had a few fittings and had to buy a few, but once its done, its done. Also alk is easy to cut into and stick another t in if you decide you need a drop where you havent got one.

 

[8ob]

@8ob what wall plate type fittings do you use? Plastic or the brass ones?

Thanks everyone

This type https://www.screwfix.com/p/compress...V5IBQBh2Zcw_9EAQYASABEgIaWPD_BwE&gclsrc=aw.ds

 

[whm_fab]

This type https://www.screwfix.com/p/compress...V5IBQBh2Zcw_9EAQYASABEgIaWPD_BwE&gclsrc=aw.ds

Looks like they (and most other brass fittings) only come in 15mm and not 20mm .. is this normal ? Can't even get 20mm brass elbows strangely

 

[8ob]

Looks like they (and most other brass fittings) only come in 15mm and not 20mm .. is this normal ? Can't even get 20mm brass elbows strangely

They are made but are ten times the price, it would be a lot cheaper to reduce down from 22mm just before the fitting.
https://www.bes.co.uk/polyfast-wall-plate-elbow-20mm-comp-x-1-2-bsp-pf-9949/

Bought something similar the other day and that was the same price

Edit


Cancel that they do exist in normal brass, these can be used with a 20mm olive conversion. https://www.plumbnation.co.uk/site/...MI-NKZgrif6wIViK3tCh3RpAQ8EAQYBSABEgK92fD_BwE



Bob

 

[Burdekin]

Go as big as you can, I use copper pipe. Air hose is another option and I currently have a big air hose linking my new part of my workshop. Be careful with plastic pipe, check the pressure rating for whatever you chose is suitable before buying.

 

[MetalMonkey]

I'm not sure how the price of the John Guest Air Line stuff compares to MDPE, it wasn't cheap but if you shop around you can find it for a reasonable price and it is dead easy to use, I did my entire system with it and highly recommend it.