... Energe-saving,enviroment friendly 4. factory in SH 2013 NEW product! World-class centrifugal compressors for industries,like iron and steel ... KwFeatures1.Shaft coupling connection, easy to change. 2,Reliable sealing system design, guaranteed to provide you with 100% oil - ... free compressed air. 3, Oil system designed to prevent pollution of lubricating oil by surrounding environment ...