With service centers nationwide and our 24-hour emergency parts guarantee, Kaeser customers can rely on the best after-sales support in the industry. From global corporations to intelligent trades businesses; from food production to aerospace: Our customers benefit day in, day out, from the quality, safety, and cost efficiency that a Kaeser compressed air supply brings. the Kaeser success story Learn about our development from a machine shop to one of the world's most successful manufacturers of compressed air systems. Oil-Free Rotary Screw Air Compressors: 100% Contaminant-Free Air for Critical Applications Engineered for maximum energy efficiency, reliable uptime, and strict compliance with ISO Class 0 air quality standards For food, beverage, chemical, and pharmaceutical manufacturing, even a trace amount of oil air contamination can cause costly downtime, batch destruction, and regulatory fines. KAESER’s oil-free rotary screw air compressors eliminate that risk entirely—delivering 100% oil-free, ISO Class 0 certified air across a complete line ranging from 50 to 450 hp with flow capacities from 140 to 1,770 cfm. Engineered around KAESER’s core principles of energy efficiency and reliable uptime, our CSG, DSG, and FSG series lower your total cost of ownership. Every unit features precision-machined airends, accessible service points to minimize routine maintenance time, and optional integrated dryers for complete air treatment in a compact footprint. Whether your facility requires an air-cooled or water-cooled installation, fixed-speed or variable-frequency drive, KAESER provides tailor-made configurations designed to handle continuous heavy-duty cycles while reducing power consumption by up to 9%. Need temporary clean air or an emergency backup? We also offer the diesel-driven MOBILAIR M500-2, a portable powerhouse delivering up to 1,600 cfm of oil-free air wherever your operation needs it most. Configure Your Oil-Free System Tell us your required flow rates and pressure needs. Our compressed air engineers will match you with the right model and configuration. Model Stationary Oil-Free Compressors Notes: All models available air-cooled or water-cooled, except: FSG 501-2 which is only available water-cooled. Most models available with either integrated (T) dryer or i.HOC (heat of compression) dryers. Choose from fixed speed or variable speed drive. See literature for details on each model. Model 1340-1600 100-150 Audit-Ready Compliance with Class 0 Certification Kaeser oil-free screw compressors meet the world's most stringent purity and efficiency certifications: ISO 8573-1 Class 0: The gold standard for oil-free air purity. FSMA & SQF: System designs that simplify your safety audits and regulatory compliance. BCAS: Adhering to best practices for food-grade compressed air. Where Oil-Free Rotary Screw Air Compressors Are Critical Certain industries cannot tolerate even trace oil contamination in their compressed air supply. In food and beverage production , compressed air may contact products at multiple points on the line, from sorting and ejecting to mixing, packing, conveying powdered ingredients, and cleaning bottles and molds before filling. Any oil in that air creates compliance exposure and product liability risk. Pharmaceutical and life sciences facilities face equally strict requirements. Drug manufacturing and medical device production demand purity that meets ISO 8573-1 Class 0 or Class 1 for oil, specifications that only a true oil-free compressor can achieve without depending entirely on downstream filtration. Chemical processors need oil-free air to maintain product purity and prevent catalyst and process equipment fouling. Semiconductor manufacturing requires extremely high-purity air where even microscopic particles can cause defects, while automotive and aerospace paint finishing and precision assembly operations rely on contamination-free air to prevent surface defects on high-value components. Built for Reliability, Serviceability, and Efficiency Reliability The rotors carry a special abrasion-proof coating rated to 575°F that will not wear over time, keeping compressed air delivery and energy consumption consistent across years of operation. Stainless steel rotors in the second compression stage ensure air quality and significantly extend service life. SIGMA CONTROL monitors more than 20 critical operating parameters, stores the last 200 operational events, and offers multiple control profiles to match compressor behavior precisely to process demand. Serviceability In the CSG series, service intervals for compressor stages and gear fluid are 50% longer than in previous designs, condensate drain maintenance intervals are three times longer, and the pulsation dampeners are maintenance-free. On larger models, both stages of the aluminum-block heat exchanger swivel out for cleaning, and the temperature-controlled standstill fan removes residual heat during standby, allowing the main fan to be switched off for quicker service access. Energy Efficiency Kaeser's oil-free rotary screw compressor models are up to 9% more efficient than competing designs. SIGMA FREQUENCY CONTROL (SFC) models use synchronous reluctance IE5 motors, and a speed-controlled radial fan on fixed and variable speed units maintains proper cooling airflow while minimizing power draw. For operations needing sub-freezing pressure dew points, our patented i.HOC (Integrated Heat of Compression) dryer achieves dew points as low as -22°F. The i.HOC uses 100% of the heat generated during the second compression stage for drying, making it effectively available at no additional energy cost. For facilities focused on sustainability, up to 96% of electrical energy input can be recovered as hot air or heated process water, with payback periods of less than a year. Air-Cooled or Water-Cooled: Choosing the Right Configuration Kaeser oil-free rotary screw air compressors are available in both configurations. Air-cooled models work where cooling water infrastructure is absent or impractical, are available up to 450 hp, and feature heated exhaust air that can be ducted directly to an adjacent space for heating without auxiliary fans. Water-cooled models are the better fit for space-constrained installations: their compact footprint and small exhaust air duct allow placement in smaller, low-ceilinged compressor rooms. For those organizations who require heat recovery for their process, there is no better option than a water-cooled, oil-free screw compressor. Furthermore, the efficiency of the oil-free screw compressor will increase with the water-cooled option. In general, air-cooled versus water-cooled compressors can be summed up in this Kaeser blog post . Frequently Asked Questions What is the difference between an oil-free compressor and an oil-flooded compressor with downstream filtration? An oil-flooded rotary screw compressor lubricates the compression chamber with oil, which then requires separation and filtration before the air reaches the point of use. Even with high-quality filtration, a small residual oil content remains, typically in the range of 0.01 mg/m³ at Class 1, and filtration efficiency degrades over time as elements age or become saturated. A true oil-free rotary screw air compressor, like Kaeser's CSG, DSG, and FSG series, uses no oil in the compression stage at all. The airend's rotor coating and stainless steel second-stage components maintain a tight sealing clearance without lubrication, so the air leaving the compressor contains no process oil, regardless of filtration condition. In regulated industries, this distinction matters significantly: An oil-free compressor eliminates the risk of a filtration failure that could cause contamination. How much horsepower do I need for an oil-free rotary screw air compressor? The right horsepower depends on your required flow rate (measured in cfm), operating pressure (measured in psi or psig), and application duty cycle. Kaeser's oil-free screw compressor line spans 50 hp through 450 hp, covering capacities from 184 to 1,774 cfm at pressures from 60 to 160 psi. For highly variable demand profiles, our SIGMA FREQUENCY CONTROL (SFC) variable speed drive models adjust motor speed to match actual demand, preventing the energy waste that fixed-speed units incur during partial-load operation. A Kaeser system design consultation will identify the right horsepower range and control strategy for your specific load profile. Can I use an oil-free compressor for food and beverage direct-contact applications? Yes, this is one of the primary use cases for Kaeser oil-free rotary screw air compressors. In food and beverage operations, compressed air is routinely used for sorting, ejecting, mixing, and packing products, as well as for transporting powdered ingredients and cleaning packaging and molds prior to filling. Kaeser's CSG series features a nanoceramic and PEEK (polyetheretherketone) rotor coating that is food-safe and free of PTFE and silicone, materials that can pose contamination risks in food-contact environments. Get the Right Oil-Free Compressor for Your Operation From 50 hp to 450 hp, we engineer Kaeser oil-free rotary screw air compressors to keep your most critical processes running cleanly and efficiently, backed by factory-trained service technicians and a 24-hour emergency parts guarantee. Tell us about your application, your required flow rates, and pressures, and our compressed air system experts will identify the configuration that fits your exact requirements. Request a quote today and put Kaeser's decades of compressed air engineering experience to work for your operation. Contact KAESER For Your Compressed Air Questions Speak with a Kaeser Compressed Air Engineer to calculate system CFM demands or request a site audit. Find your local distributor Your local branch or distributor should be your first stop when you have a question, need a quote, parts or service.