Oil free air compressor

OF Series Oil-Free Rotary Screw Air Compressor – 60-600 HP

Elgi

ELGi is amongst the few screw air compressor manufacturers with an in house designed and manufactured oil-free airend. ELGi’s oil-free range provides class zero oil-free air with leading energy efficiency, reliability, and low operating costs, supported by a Best-in-class warranty.

Brochure Specifications Get a quote

Features

OF Series: Oil-free Screw Air Compressors. Oil-free air for all sustainable air needs.

A Lower speed of airend: Provides better reliability due to lower gear ratios

The usage of rigid Stainless Steel tubes: Improves product reliability and reduces maintenance

Reduced pressure differentials: load-unload pressure differential is 2.9 psi: Reduces stress on the motor

Tropical design: Ensures reliable operation at severe working temperatures (23ºF to 113ºF)

Efficiency / Cost of Ownership

Low life cycle cost- High-energy efficiency design delivers maximum UPTIME and lower cost of ownership

Operates on low-pressure cooling-water head: Reduces power consumption of feedwater pumps

Lower temperature differential of cooling water: Power savings by reducing cooling water pump sizing

Optimized airend design delivers the best efficiency in its class at different pressures, providing a quicker return on investment

The OF series compressor package ensures that cooling water in-out temperature differential is only 14ºF compared to other conventional systems with 57.2ºF: Ensures lower thermal stress to the system, a better fouling factor and a lower cost of ownership

Consistent Air Quality

Consistent oil-free air meeting ISO8573-1 class 0 oil standards.

Food-grade coating is done where air contacts the metal surface inside the compressor: Ensures consistent oil-free air without metal debris

Pipes have special e-coating: Ensures consistently clean and oil-free air

Optimized rotor clearances: Ensures consistent air delivery as rotor coatings remain uniform

Specifications

Two-Stage Water Cooled OF Series: 125-500 HP	Two-Stage Air Cooled OF-A Series: 60-250 HP	ISO 8573-1, Class "0" Oil-free air
UPTIME Assurance Intelligent Control for Consistent Air Quality and Increased Uptime	Variable Frequency Drives (VFD)	ELGi’s unique eta-V rotor design reduces pressure losses and increases stage efficiencies

Attributes and benefits

Coolers

Cupronickel coolers with water-in-tube system and is designed for temperature difference of max. 14ºF
Better Corrosion resistance and 28 times better thermal conductivity than stainless steel

Rotor

Patented eta-V profile with 3/5 lobe for high swept volume and lower pressure ratio
Rotor operates at a lower speed due to the patented profile and fewer inter-lobe Leakages
Rotor and housing are coated with PTFE-based food-grade PP coating to resist
Corrosion and endure at high temperatures up to 482ºF. This results in optimum long-term performance with no loss of efficiency

Capacity Control Valve

Hydraulic rack and pinion-type actuation
Valve membrane made of stainless steel metal instead of elastomer
More than one million cycles of life between rebuilds
Simultaneous closing of inlet valve and opening of blow-off valve by rack and pinion to ensure safety and air-end life
Less maintenance compared to electrically actuated valves

Air Seal

Carbon-impregnated SS floating type seals
Axially locked by Belleville spring and radially locked by compressed air

Oil Pump

Separate motor-powered oil pump ensures lubrication before and during start of the machine (ensuring no dry running of gears and bearings)
All oil tubing is made of Stainless Steel to increase reliabilityrnrn

Timing Gears

Helical gears, precision ground to DIN 4 quality and case hardened to minimize transmission losses and noise during operation
Dynamically balanced to reduce vibrations by optimizing the loads on bearings and increasing bearing lifern