Compressed air bottle wall thickness

[hacklordsniper]

Maybe depends on the teritory, but all tools here from Lidl (Parkside) and some other centers come from Einhell China. They even leave original Einhell manual

 

[gus]

There is also a possibility the compressor heads are made in China and shipped to other locations for packaging that is mounted on to air receivers and coupled to motors. This is a good arrangement as the final labour input decides the final quality. I have seen misaligned belt drive, bad piping,air leaks and bad paintwork or good paintwork trying to hide bad welds on MIC packages.
Fiacs and Abacs imported into China in the early 80s in many containers by my friends were copied within a year or so and flooded the China market within two three years.Some were pretty good but most garbage. The better qualities survived. Even Ingersoll-Rand Heavy Duty
Air Compressors was pirated but failed the market requirement.
An average air compressor plant is supported by many supporting suppliers. Castings,raw or machined,pistons,rings,motors etc. All out to give you the best price but quality compromised.
Gus spent too many years in China. And being able to speak the mother tongue fluently helped. Currently there are too many plants assembling Screw Compressors using imported air ends as good MIC airends are almost non-exstent. The heavy weights-----Ingersoll-Rand,Sullair,Atlas-Copco etc are there assembling good quality packages. Best not to buy MIC Screw Compressors from home grown plants.

 

[hacklordsniper]

That is impressive knowledge mr. Gus, i really like to listen about it. And how is that MIC cannot make a screw compressor, i would expect a such developed country to make a better quality compressor anytime. Or they know how, but they rather focus on low price, high profit?

 

[gus]

That is impressive knowledge mr. Gus, i really like to listen about it. And how is that MIC cannot make a screw compressor, i would expect a such developed country to make a better quality compressor anytime. Or they know how, but they rather focus on low price, high profit?

I was with Shanghai Air Compressor Plant in 1986 when they bought Holroyd Milling Machines to cut screw rotors.And rotor profile grinding machines. Cutting and grinding male and female rotors wasn't that easy. Its takes a mountain of scrap rotors to master the art. The Swedish will swear to this. Ruptured rotor shafts is one horror to contend with. The total committment to quality is still not there.
There are some plants that import rotors from Germany and Sweden and cut own air end housing. Tolerance is in microns. The Indians cut their own rotors and air ends with success and good results. The Chinese will take a while more to catch up.
The Chinese bearings just not good enough to be used with screw compressors.

 

[hacklordsniper]

I have some more questions regarding compressed air.

Im planning to make an permamnent wall installation to machines where i will need air often. I have at disposal all that is required in 6 mm tubes, and various fittings for 6 mm tubes.

However i wonder is 6 mm (outside diameter, 5 mm (inside diameter) tube enough for supplying air to an air wrench that tightens the tool in the mill (power drawbar)? I have no specification on it, except it needs 8 bar

 

[gus]

For small air tools,it best to go for 1/4'' -------3/8'' I.D hose. For bigger air tools 1/2''-----1''.Hose to ensure you have 100psig at tool air inlet. Too small a hose will cause excessive pressure drop.All air tools have a specified air consumption rate per minute. at 100psig. It is best to supply above the required cfm aka cubic feet/minute.Under capacity air supply renders tool to consume too much air w/o coming to best
performance.Impactools are very unforgiving and will not loosen/tighten a nut/bolt.
At ingersoll-Rand we use a needle pressure gage to pierce through hose to read inlet pressure at air tool inlet. Small air grinders and drills will need 10hp air compressor in order to operate
continuously.

 

[ShopShoe]

hacklordsniper,

Gus, if you're following, perhaps you can confirm this.

I prefer piping for any installed air lines, hoses used for portable uses. (Of course, whatever you use must be up to the pressure: No bargain-basement unrated pipe or tubing.)

I have followed recommended practice of sloping lines so moisture does not stand in pipe. I have seen recommendation to slope back to compressor tank, or slope to farthest air outlet. I have done it both ways, in different installations.

Any place where there is a low spot in the line, a drain valve must be installed to let off condensation, or you will be working along and suddenly your air hose will "burp" some water: Not good if you are painting your three-year-long car restoration project at the time.

I have lines pressurized at full tank pressure, then use regulators, filters and moisture traps at output points where tools are connected. I have used 3/4-inch piping for installed lines, then 3/8-inch hoses to tools, except for smaller hoses used for things like spot detail paint gun and "chip blower" on milling machine. I have been using a 5-HP, single stage compressor, but the tank just rusted out and I am contemplating what compressor I will end up with.

(Gus, I was shopping and looked at some Ingersoll-Rand shop compressors that had "Made in China" stated prominently and in large bold type on the pumps --thought of you. Not sure I'll buy one, though.)

Regards to all,

--ShopShoe

 

[gus]

hacklordsniper,

Gus, if you're following, perhaps you can confirm this.

I prefer piping for any installed air lines, hoses used for portable uses. (Of course, whatever you use must be up to the pressure: No bargain-basement unrated pipe or tubing.)

I have followed recommended practice of sloping lines so moisture does not stand in pipe. I have seen recommendation to slope back to compressor tank, or slope to farthest air outlet. I have done it both ways, in different installations.

Any place where there is a low spot in the line, a drain valve must be installed to let off condensation, or you will be working along and suddenly your air hose will "burp" some water: Not good if you are painting your three-year-long car restoration project at the time.

I have lines pressurized at full tank pressure, then use regulators, filters and moisture traps at output points where tools are connected. I have used 3/4-inch piping for installed lines, then 3/8-inch hoses to tools, except for smaller hoses used for things like spot detail paint gun and "chip blower" on milling machine. I have been using a 5-HP, single stage compressor, but the tank just rusted out and I am contemplating what compressor I will end up with.

(Gus, I was shopping and looked at some Ingersoll-Rand shop compressors that had "Made in China" stated prominently and in large bold type on the pumps --thought of you. Not sure I'll buy one, though.)

Regards to all,

--ShopShoe

Spent two years to get them up and running,using heads from Ingersoll-Rand India. Air receivers are made to ASME and certified by the Nanjing Pressure Vessel Bureau. Chaperoned 6 Seniors Engineers for training at Ingersoll-Rand,Campbellsville Compressor plant back in 1986.

Air Mains.
For a small shop 3/4 '' Copper pipe or G.I. Pipe(thick great). Slope main pipe
1'' every 30 feet to drain moisture at lower end.have a drop pipe or drain leg. Tap main pipe with tee facing upwards to avoid moisture pick up.

See hand sketch. Sorry. My CAD or TurboCad has yet to happen.

 

[hacklordsniper]

Thank you Gus for all of your great advices. Since you are good compressor "know how", can you tell me howmuch useful is to install large after cooler on compressor (between output and tank)?

 

[hacklordsniper]

My new compressor arrived, sadly it was leakin oil out of the box. So they replaced it with a new one, and now everything is ok.

Nice unit, silent, beautiful. I have decided not to install any permanent installations. At output of compressor i installed a filter and quick coupling. At every machine i installed filter and oiler and quick coupling. So i connect a hose, where i need and when i need. As the shop is expanding all the time and im changing the location of machines i decided permanent installation is not a good idea.