Compressed Air Pressure

Instead of using compressed air,why don't you use vibrator type packer operated by electricity?.

Check out surge tanks. Depending on how long the air pressure drops.

I would look at size of the air piping from your compressor to the machine. If machine demand is momentarily high, there may be considerable pressure drop in the piping.

For example, say that the average air consumption is X, which could be 4X for 1/4 of the time, and zero the rest of the time. Your piping should then be sized for 4X rather than just X. Is your air receiver near the machine, which would help; or is it at the (perhaps remote) compressor?

Lyn's idea may be just the ticket; a small receiver (surge tank) near the machine could avoid a need to enlarge any piping.

Find the cause of the pressure drop, and fix it.

Normally a storage tank with drain tap is used with compressed air system. Have you got one,what is its capacity?. what is your consumption rate(l/min) and total required for a day as well as how many hrs do you use it?.

What happens during the "sometimes"? If possible, eliminate the condition. If not, check max pressure of compressor and system. Many compressors are rated for 7 barg or more and it may be possible to increase the pressure control (e.g. pressure switch) settings.

Codey

If the pressure decrease is occasional, as I think you indicate, you may be able to identify what is happening then--like, is another machine starting its air request.

Thanks all for your valuable comments. will use this knowlodge to solve the issue

Hi L.Ramamurthy,

Lots of good ideas for you to check out, also very important you have no air leaks in your system.

Best of luck,

John

I'm surprised that no one has suggested what seems to me to be obvious: install a pressure switch that stops the machine whenever the pressure drops below the minimum required.

Obviously it would be preferred to eliminate the pressure drops, but until that problem is remedied, such a switch could prevent the malfunction.

Check for water buildup in the compressor tank. It may be affecting the total available air by shutting off before there's enough reserve. There are automatic bleed valves available that will solve this problem. They drain a little water each time the pressure cycles. Analyze graphically the various cycles between the compressor and the packing machine. Get back to us.

Mr Ramamurthy

Pl check the requirement of your FFS m/c. What is the CFM required and how much CFM is generated at the compressor. This is purely the capacity problem of compressor. Check any leakages / bends in the pipe.

Thanks and best wishes

Susheel

What is the pressure in the receiver? If it always above 6.5 bar then the problem is in the filter or regulator. Can you install a pressure gauge between the filter and regulator to see if it is the filter?

An 8.3% "safety" margin on air pressure is normally too small, but assuming it is difficult (or expensive) to improve the supply.

Locate the 'mechanism' within the machine that causes the malfunction. A simple solution may be found, eg the addition of a spring (or springs), the replacement of a bearing, the removal of some mass (reduced inertia), changing a valve, improving the timing of operational sequence. A good design engineer will understand the machine, and may see a solution.

I would check pressure drop across inline filters and Dryer. we had a dryer that was plugged enough that it wouldn't let enough flow out to shop and would gradually drop pressure in shop but maintain at receiver tanks

Also check for people using air guns at full pressure. this will also drop your pressure at random times. Regulate them.

Check the cut-on pressure for your compressor, it may be set close to the 6kg/cm2 you need. In that case, any restriction in your air line, or other users could lower the available line pressure, just before and just after the compressor cycles back on. The spring on the pressure switch could have weakened over time, or the diaphragm inside the switch may have stiffened up, causing it to cut back on at a lower pressure.

If the entire line is not robotic, then I would video the area where bagging is taking place, and also near the compressor, to check for nefariously lazy employees who want the line to stop. Stranger things have happened. Perhaps they are momentarily blocking the intake to the compressor. Isolate by all means, the mechanical sources of the problem, then look at the human one if no answers arise.

All air compressors has upper and lower cut off point. It seems when it is at lower cutoff point ,some other equipment also draws in good amount of air, leading to drop in line pressure, inadequate for this equipment.

The solution lies in using an intensifier to boost the pressure. If your other equipment are happy with 5 Kg/cm2 or lower, generate compressed air at lower pressure and just intensify for this equipment.

Many a time buyers overlook fine print in approval sheet of seller and land into this problem. With standard 7kg/sq.cm air pressure compressor the equipment should be specified with maximum 5.5Kg.sq.cm.

Intensifiers are available in Indian market.

Hi editor1947,

The problem with intensifiers is that they are huge consumers of air. It would most probably exacerbate his problem.

Best regards,

John

...or shift it to another machine...

0.5 bar out of 6 bar shouldnt normally cause malfunctioning of your equipment, you may need to check the cylinder or user component that is so sensitive to the air pressure drop. Something could be making it sticky or somehow malfunction. You can also, if its determined its a compressor cfm inadequacy, generate your air at higher pressure but install a regulator at the reciever outlet

Another thought crossed my mind...

Perhaps it is actually the malfunction causing the pressure drop, not the other way around. Perhaps an intermittent leak inside a cylinder or valve dumping air to exhaust.