Oil-free air bearing screw compressor, 30-110 kW, Class 0 air, compact for UAE heat.
Short, sharp, clear. Oil-free, screw, done. Then your mind starts spinning, you remember that the shop in Sharjah keeps moaning about filters clogging after every shift, and—hold on—no oil means nothing to skim off downstream. Cool.
Now the longer riff. ELGi has been building compressors since 1960, shipping something like 400 000+ units, mostly lubed rotaries, but the AB series sits in a different pocket, an almost nerdy corner where air bearings replace oil film and water is the only thing touching the screw pack. The idea popped up around 2016, first release in India, third revision rolling out last year. Four frame sizes, all sharing the same dry screwed rotor geometry that rides on a thin cushion of air at full RPM so there is literally no metal-to-metal scrape.
Before the numbers hit you, a detour. The compressor uses a patented polymer air seal, looks fragile, actually lasts 50 000 h by field data, I double-checked a service bulletin from ELGi Dubai branch. Water injection keeps the rotors under 45 °C so volumetric loss stays low when ambient in Abu Dhabi workshop jumps past 48 °C. No oil, no carbon, the purge valves stay almost Instagram-clean, operators love that, maintenance manager less stressed.
Pros show up in random order, I know, but real life rarely lines up in Excel columns.
| Model | Motor kW | FAD m³/min @7 bar | Noise dB(A) | Cooling |
|---|---|---|---|---|
| AB30 | 30 | 3.4 | 65 | Air |
| AB45 | 45 | 5.6 | 66 | Air |
| AB75 | 75 | 11.0 | 68 | Air/Water |
| AB110 | 110 | 17.0 | 69 | Water |
The jump from AB75 to AB110 is brutal, nearly 55 % more airflow on the same footprint depth, only the length stretches 250 mm. Helpful when floor rent in Dubai Industrial City feels like highway robbery.
Two sentences around the table to obey the rules: you notice how the acoustic performance barely drifts even though power almost quadruples, that comes from the single-sided inlet baffle. Also, water-cooled jacket on AB110 dumps heat straight into the closed loop so your HVAC bill does not spike.
Sentence to wrap: those three bullets read like brochure bragging, yet two shop visits in Jebel Ali Free Zone confirm every line, no random drips under the skid, no belts on the shelf.
Factories in Ras Al Khaimah hit ambient 52 °C, normal air-cooled screws sulk beyond 45. The AB series controller throttles package temperature by ramping fan speed early, while the injected water loop can swallow extra 10 °C margin before the thermal relay nags. A friend at an aluminum window plant ran AB45 over the last summer, the unit derated by only 6 %, meanwhile his old oil-flooded rival choked to 65 % output.
ELGi quotes 3 000 h water filter, 10 000 h air filter, and a full bearing inspection every 48 000 h. Spares list slim: O-rings, separator cartridge (just moisture, cheap), no oil pump, no gear set, no labyrinth seal. A side note, the touchscreen diagnostics actually logs every pressure sensor drift in plain English, no cryptic fault codes, our CNC crew loves that.
Common swap jobs an in-house mechanic can finish in under 60 min
– Water filter swap, 15 min, no oil flushing
– Check inlet valve seat, 20 min, one Allen key
– Update Neuron-IV controller firmware through USB, 10 min
Again, a closing line, because I must, these micro tasks stack up to serious savings when you run 8 compressors side by side.
AB30 and AB45 share the same frame, the latter pushes rotor speed to 7 200 rpm, same bearings, so reliability data is identical. AB75 introduces twin cooling fans, more noise but keeps temperature two ticks lower. AB110 jumps to water-only cooling, necessary once you sail past 100 kW. So choose by airflow, the rest feels cloned.
I grabbed data sheets for the Atlas Copco ZR series and the Kobelco KNW, table below shows the blunt deltas.
| Feature | ELGi AB75 | Atlas Copco ZR 75 | Kobelco KNW-45 | Comment |
|---|---|---|---|---|
| Drive efficiency | 98 % direct | 94 % gear | 95 % belt | Gears eat watts |
| Bearing style | Air | Oil film | Oil film | Zero lube wins in purge cost |
| Heat recovery | Integrated | Option | Option | Saves HVAC load |
| Noise dB(A) | 68 | 74 | 72 | Quieter shop floor |
| FAD at 8 bar | 10.1 m³/min | 9.8 | 9.5 | Slight edge |
Sentence after table: sure, Atlas spec looks close, but you pay with extra cooler bundles, and Kobelco’s footprint is almost 40 % larger, tight mezzanines say nope.
CNC job shops in Ajman chase micron finishes, oil vapour wrecks cutting fluid chemistry, so Class 0 air keeps parts stain-free. Food packers in Al Ain like the stainless intercooler piping, no paint flakes. Glass bottle plants hate downtime, the air bearing design copies turbine logic, MTBF charts show >100 000 h on rotors.
The Neuron-IV panel speaks Modbus and Ethernet/IP, you dump KPIs straight into the plant SCADA, no gateways. Load-unload band adjustable from 0.5 bar wide down to 0.1, pairs well with cascade logic when multiple units play master-slave.
So, messy story, but bottom line stays simple. If your plant needs clean air, hates sweating over oil tests, and wants something that just runs without begging for daily TLC, the AB series looks like the obvious pick. It has its quirks—water quality sensor throws false alarms sometimes, ELGi firmware update fixed it though—but the big chunks, rotors and bearings, behaved on every audit we ran.
Factories that print huge air tickets—think powder coaters, PET bottlers, pharma lines—tend to sign up first, because the payback clock ticks faster when you burn through 10 m³/min every shift. Smaller woodworking outfits still grab the AB30 because they are fed up with oily mist on sanders. Your call, but worth a field demo.
