Non Lubricated Compressors..

Replies

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  Jacob George

  Sanoj Rajan

  Non Lubricated compressors are nothing new..
  But different manufacturers use different techniques, and different materials..
  I am right now working on a project with non-lubricating compressors..
  Can you please help me!!

  By non-lubricating I shall assume that the piston and cylinder will be non-lubricated, but the cross-head, crank, bearings etc. will be lubricated. Such compressors are extensiveoly used in the PET bottle blowing industry where oil free air is necessary. Such compressors are manufactured by ABC (Spain), Ateliers & Francois (Belgium), Atlas Copco etc. There are proprietary ring suppliers for these compressors. However if the application is different such as oxygen compressors etc. oil has to be completely isolated from the gas. They are a different class.
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  Sanoj Rajan

  Jacob George

  By non-lubricating I shall assume that the piston and cylinder will be non-lubricated, but the cross-head, crank, bearings etc. will be lubricated. Such compressors are extensiveoly used in the PET bottle blowing industry where oil free air is necessary. Such compressors are manufactured by ABC (Spain), Ateliers & Francois (Belgium), Atlas Copco etc. There are proprietary ring suppliers for these compressors. However if the application is different such as oxygen compressors etc. oil has to be completely isolated from the gas. They are a different class.

  Yeah its for PET bottle blowing.
  But wont the piston ring wear out soon if its non-lubricated??
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  Sanoj Rajan

  And if the crank is lubricated, won't the oil fumes mix up with the compressed air?
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  Ramani Aswath

  Types of Air Compressors
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  Jacob George

  Sanoj Rajan

  Yeah its for PET bottle blowing.
  But wont the piston ring wear out soon if its non-lubricated??

  Please see compressor construction (example) picture in the following link:
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  Of course the rings will wear, usually they have to be changed 8000 to 12000 hours operation.
  The oil is kept entering the compression chambers by a series of gland packings and and scrapers. Perhaps ppm level of oil might pass through, but always there are special filters in the compressed air line.
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  Sanoj Rajan

  bioramani

  Types of Air Compressors
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  Thank you very much sir!!
  these links have proved to be very useful.
  I was thinking about innovating it, and forgot about the very obvious one.
  Thanks.
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  Sanoj Rajan

  Jacob George

  Please see compressor construction (example) picture in the following link:
  #-Link-Snipped-#
  
  Of course the rings will wear, usually they have to be changed 8000 to 12000 hours operation.
  The oil is kept entering the compression chambers by a series of gland packings and and scrapers. Perhaps ppm level of oil might pass through, but always there are special filters in the compressed air line.

  
  Yeah, i have been through the scrappers and the wiper rings.
  But the one that i am working with doesn't last long. That's the reason i am looking for something else. Compressor, with no oil at all !!
• 

  Jacob George

  Sanoj Rajan

  Yeah, i have been through the scrappers and the wiper rings.
  But the one that i am working with doesn't last long. That's the reason i am looking for something else. Compressor, with no oil at all !!

  Glad to be of help, welcome anytime. In the food industry, (not pharma), I have seen people using normal (oil lubricated )high pressure compressors and a set of special filters remove the oil content to a satisfactory level. If you are thinking of making a compressor, the critical points will be balancing of mechanical components, balancing air out put of each stage and cooling- do not forget the intercoolers and safety valves for each stage. The AF compressor has three stages-4, 16 and 40 bar.
• 

  Sanoj Rajan

  Jacob George

  Glad to be of help, welcome anytime. In the food industry, (not pharma), I have seen people using normal (oil lubricated )high pressure compressors and a set of special filters remove the oil content to a satisfactory level. If you are thinking of making a compressor, the critical points will be balancing of mechanical components, balancing air out put of each stage and cooling- do not forget the intercoolers and safety valves for each stage. The AF compressor has three stages-4, 16 and 40 bar.

  Thank you so much sir for your insights.
  Just one last thing. What material can be used for the piston rings? The conventional ones can't be used, are they'll wear out pretty soon. The one that i am working with is CFT (Carbon Filled Teflon). Do you have any other materials in mind which would increase the life?
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  Jacob George

  Sanoj Rajan

  Thank you so much sir for your insights.
  Just one last thing. What material can be used for the piston rings? The conventional ones can't be used, are they'll wear out pretty soon. The one that i am working with is CFT (Carbon Filled Teflon). Do you have any other materials in mind which would increase the life?

  This is specialist territory, I doubt even the compressor manufacturers have an idea about that.
  There are specialist ciompanies supplying rings.
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  Sanoj Rajan

  Jacob George

  This is specialist territory, I doubt even the compressor manufacturers have an idea about that.
  There are specialist ciompanies supplying rings.

  Yeah. Well, thank you very much for your help.
  Looking forward to have many more wonderful discussions with you.
  Thank you.
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  Ramani Aswath

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  Sanoj Rajan

  bioramani

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  Yeah, i did some digging on PTFA, and found it has better life than Teflon or Carbon rings.
  While doing so, i also found another material, BAM (Aluminium Magnesium Boride). But i'm not sure whether it is available in the market, or still research work is going on.
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  Ramani Aswath

  Teflon is Dupont's trade name for its brand of PTFE. Carbon filled PTFE has potential. ANother material that has even much better wear properties is UHMWHDPE (ultra high molecular weight high density polyethylene) The only problem is that it has poorer thermal properties than PTFE. However, I would strongly recommend trials with this. It has unbelievable wear resistance. I have been using this material extensively for the past 30 years.
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  Sanoj Rajan

  bioramani

  Teflon is Dupont's trade name for its brand of PTFE. Carbon filled PTFE has potential. ANother material that has even much better wear properties is UHMWHDPE (ultra high molecular weight high density polyethylene) The only problem is that it has poorer thermal properties than PTFE. However, I would strongly recommend trials with this. It has unbelievable wear resistance. I have been using this material extensively for the past 30 years.

  OK. Now we are getting somewhere. I will discuss about this with my team members, and i will get back to you ASAP. Thank you for your valuable time sir. I am really very greatfull sir.
• 

  zaveri

  Here is another suggestion.
  
  how about using self-lubricating machine parts.
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  Sanoj Rajan

  zaveri

  Here is another suggestion.
  
  how about using self-lubricating machine parts.

  what kind of self-lubricating machine parts?
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  Ramani Aswath

  Many engineering polymers (Nylon, Polyimides, PTFE and UHMWHDPE) can be produced as composites with integral solid lubricants like Molybdenum Disulfide or graphite. These are dry lubricated and can work without extra lubrication. All are commercially available.
  Solid Lubricants