Questions For Professor Compressor

I have a 5? HP C/H on a 60 gallon tank. It is wired for 220. I will be using it in my hobby shop to run air tools and some painting.

I am planning to run a black iron pipe distribution system. Are there any special considerations, i.e, size for distance. I was thinking 1/2" for the main lines and 3/8" for the drops. The shop is 30' x 40' and the longest run will be about 70'. Any recommendations?

I am confused by all of the different filters, seperators, dryers, and oilers. I am assuming that I will need a dryer/filter and oiler on the lines to my tool outlets and a dryer/filter on the dedicated painting line. Can you suggest a layout and economical components. Most of the stuff I see is tapped for 3/8 NPT and I guess I would need units tapped for 1/2" NPT.

Impressed with the advice you gave earlier. Good to have someone wth your knowledge posting here.

Steve in Arkansas

According to the specs in my manual, 1/2 schedule 40 pipe will experiece a .67 psi pressure drop flowing 15 cfm for 100ft of straight pipe at 125 psi. Things like elbows, tees, valves and increasing corrosion will aggravate this pressure drop somewhat, but unless you are demanding a lot of air, it should be ok. Bigger is better, but your compressor will probably not put out as much air as the pipes can flow anyway. You could put a small secondary tank in the part of the line that is furthest away from your compressor to help deal with pulse loads, and provide a remote drain point for any moisture. You should put some drain legs along your pipe run as well. BTW, when you are buying all your couplers, make sure they are all the same type. There are subtle differences that make the different types non interchangable.

Bye.

Professor Compressor? Doctor Compressor? You guys are relly setting me up for a fall! LOL
I hope I am not coming across as a know it all.

I will have to get my reference manual to get a definitive answer on your pipe size, so I will leave that for later. First impressions are that you will be fine, but I will have to look up specs on pressure drop through lengths of pipe to be sure. If possible, and affordable, it would be a good idea to run a complete ring around your shop. This way, the air can move in whichever direction poses the least resistance to flow. It is a good idea to slope you pipe slightly downward towards your compressor to encourage moisture to flow back to the tank, but this may be a lot of work for little gain in your installation.

Filters come in different styles. Coalescing filters have a soft absorbent material that lets air pass, but retains oil and, to a lesser extent, water. They are usually first in line and do the messy work. Then there are particulate filters that tend to often be made of either sintered metal, porous plastic or porous ceramic. These generally have a coarser filter material than coalescing filters and are mainly designed to trap debris like rust and scale from previously dried air. Lubricators inject a fine oil mist into the air stream to take care of things like die grinders and impact guns which often get little regular maintenance and are used for short periods of time, a prime scenario for rust build up. Definately not to be used on any line dedicated for painting. If I were you, I would put a main coalescing filter and particulate filter right in the air line at the tank for primary filtration. Then, I would take another filter, or a lubricator, depending on what you are doing, and put a male and female quick coupler on them, taking note of any arrows that denote which way the air should flow through them. That way, you could plug them temporarily into whichever coupler you are working from at the time, and then remove them when you are finished, that way you are not tied in to using just one coupler for painting and another just for your air tools, etc. Do NOT use the same air line to paint with that you just sent lubricated air through though. You will need a dedicated paint gun hose if you are lubricating air for your tools. The oil will be sent through the hose. Remember to put a valve in line before your filters at the tank so you can check or change them without having to blow down the tank first to gain access. One after would be nice too, to keep the line pressurized (there are usually drain valves on the bottom of filter cannisters which you can use to depressurize them with). You can buy something called an FRL (Filter regulator, lubricator) which is one monolithic piece. They are useful and can sometimes be cheaper than buying each item seperately, remembering of course not to put a lubricator in line with a paint gun. Wilkerson makes some reasonably cheap filters and lubricators. Lincoln is also a very well known brand. Wilkerson is a British product and Lincoln is American, if that is important to you. These are just two of a million, billion different filter manufacturers. Buy something you KNOW you will be able to get replacement filters for. The sheer number of manufacturers is staggering and interchangablity of parts is virtually zero. Keep in mind that Wilkerson and others often use plastic bowls in their filter assemblies. This is perfectly fine but be aware that some solvents or syntheics oils are not compatible with them and may cause them to weaken or soften, leading to failure. You can usually get metal bowls for more money. I MUST remember to bring home my manual.....darn those aluminum pots!!