A variety of air compressors are available in the market of which oil-less air compressors are used to provide oil-free compressed air. They are used in critical operations, where products or processes could become contaminated if subjected to small amounts of oil. Contamination may result in costly scrapping of product and/or production downtime to clean or purify the system. Oil-less compressors may also be used with additional purifying filtration and safety controls to produce air for breathing applications in industry and medical systems.
Oil-less reciprocating air compressors consist of dry compression chambers using synthetic self-lubricating guide rings and piston rings. The lower end running gear employs sealed main ball bearings and sealed connecting rod bearings so no oil is used in the crankcase. The complete absence of oil in this design eliminates the possibility of oil migration from the crankcase to compression chambers, which may be a concern in compressor pumps which may be classified as “oil-free”.
Why Opt for Oil-free Solutions?
There are several reasons why oil-less air compressors are the better option. Here are a few:
- Ensure zero contamination of oil within the production process.
Most applications using lubricated air compressors require the oil to be filtered out and removed from the process. The cost of labour intensive filters, and replacement elements is eliminated with our oil-less compressors.
Most municipalities have bylaws which make it illegal for compressed air users to dump oil-contaminated condensate into city drains. Compressing air produces condensate as a by-product. This condensate becomes contaminated with oil when lubricated compressors are used. To legally dispose of condensate which is contaminated with oil, the user is required to first separate the oil content from the water. This requires an oil/water separation system. The user may dump the water portion to a city drain, but must dispose of the oil content to a designated facility for re-cycling. The costs associated with the maintenance of the separation system and the labour to dispose of oil, are costs which are not required with oil-less compressors.
Routine maintenance for the changing of oil in lubricated compressors must normally be performed on a time basis. The cost of labour for oil changes, and the cost associated with purchasing oil, and more significantly the cost of disposal of the spent oil, are eliminated with oil-less compressors. Oil-less reciprocating compressors will operate for up to 8000 hours before major items such as piston ring and bearing replacement is necessary. Considering a properly sized start/stop operating system, this may result in 4-8 years of operation before major maintenance is required, during which time intake air filters and vee belt replacement will be the routine maintenance components.
Compressed air is normally exhausted by the tools and equipment being driven by compressed air within the production work place. When lubricated systems using filtration to remove oil are not properly maintained, oil aerosols may be dispersed into the production environment. A clean environment using oil-less compressed air benefits workplace safety and employee health.
Oil-less air compressors are used in industries and applications where oil contamination is intolerable. They are used in hospitals, pharmaceutical applications, laboratories, and food and beverage industries among others. Clean air is of the utmost importance in some applications for increased productivity, safer operation, and reduced process down time.
The modest capital cost expenditure to up-grade to an oil-less air compressor system should be carefully considered over the high cost of long term maintenance issues noted above.