Low-pressure screw
Lubricated screw compressor designed for 3 to 5 bar, from 22 to 250 kW: a large flow at low pressure, without throttling air produced at 8 bar.
27 models in the catalogue, flow 6.08 - 68 m³/min, pressure 3 - 5 bar, noise level 62 - 80 dB(A).
How it works ↓
What is a low-pressure screw compressor?
A lubricated screw designed for 3 to 5 bar, not an 8 bar machine throttled down: for the same power, it delivers far more flow. Every bar produced in excess costs about 7% in energy; producing at 8 bar to use air at 4 means throwing the difference away.
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Made for
- Pneumatic conveying, fermentation
- Textiles, glassmaking, industrial drying and blowing
- A large flow at low pressure, all day long
Not made for
- A workshop network at 7 or 8 barFixed-speed screw
- Wastewater basin aeration, below 1 barAir-bearing turbo blower
| Reference | kW | HP | Flow by pressure (m³/min) | dB(A) | Outlet | L × W × H (mm) | Weight |
|---|---|---|---|---|---|---|---|
| CZ-SLTLS-22S | 22 | 30 | 3 bar2.9-6.474 bar2.43-5.425 bar2.06-4.59 | 62 | DN50 | 1415 × 1030 × 1330 | 1,330 kg |
| CZ-SLTLT-22T | 22 | 30 | 4 bar2.74-6.085 bar2.55-5.65 | 65 | DN40 | 1610 × 1050 × 1380 | 1,100 kg |
| CZ-SLTLS-30S | 30 | 40 | 3 bar4.21-9.374 bar3.39-7.555 bar2.88-6.42 | 65 | DN65 | 1900 × 1200 × 1650 | 1,420 kg |
| CZ-SLTLT-30T | 30 | 40 | 4 bar3.74-8.335 bar3.41-7.58 | 65 | DN50 | 2020 × 1290 × 1600 | 1,200 kg |
| CZ-SLTLS-37S | 37 | 50 | 3 bar5.08-11.294 bar4.18-9.35 bar3.67-8.16 | 65 | DN65 | 1900 × 1200 × 1650 | 1,420 kg |
| CZ-SLTLT-37T | 37 | 50 | 4 bar4.5-10.025 bar4.13-9.19 | 65 | DN50 | 2020 × 1290 × 1600 | 2,000 kg |
| CZ-SLTLS-45S | 45 | 60 | 3 bar5.71-12.74 bar5.07-11.285 bar4.24-9.43 | 68 | DN80 | 2160 × 1450 × 1750 | 1,900 kg |
| CZ-SLTLT-45T | 45 | 60 | 4 bar6.43-135 bar5.36-11.93 | 65 | DN50 | 2285 × 1500 × 1710 | 2,100 kg |
| CZ-SLTLS-55S | 55 | 75 | 3 bar7.07-15.724 bar5.95-13.235 bar5.22-11.62 | 68 | DN80 | 2160 × 1450 × 1750 | 1,900 kg |
| CZ-SLTLT-55T | 55 | 75 | 4 bar7.35-16.355 bar6.76-15.03 | 65 | DN65 | 2285 × 1500 × 1710 | 3,500 kg |
| CZ-SLTLS-75S | 75 | 100 | 3 bar9.82-21.844 bar8.56-19.045 bar6.8-15.12 | 68 | DN125 | 2900 × 1830 × 2000 | 2,700 kg |
| CZ-SLTLT-75T | 75 | 100 | 4 bar9.37-20.845 bar8.65-19.23 | 68 | DN65 | 2285 × 1500 × 1710 | 3,750 kg |
| CZ-SLTLS-90S | 90 | 120 | 3 bar11-24.654 bar9.63-21.415 bar8.57-19.06 | 73 | DN125 | 2900 × 1830 × 2000 | 3,800 kg |
| CZ-SLTLT-90T | 90 | 120 | 4 bar11.63-25.855 bar10.63-23.63 | 70 | DN80 | 2800 × 1700 × 1950 | 3,800 kg |
| CZ-SLTLS-110S | 110 | 150 | 3 bar13.56-30.154 bar11-24.455 bar9.65-21.46 | 74 | DN125 | 2900 × 1830 × 2000 | 4,000 kg |
| CZ-SLTLT-110T | 110 | 150 | 4 bar14.44-32.115 bar13.21-29.37 | 72 | DN80 | 2820 × 1730 × 2100 | 4,200 kg |
| CZ-SLTLS-132S | 132 | 175 | 3 bar16.38-36.414 bar13.55-30.135 bar11.69-25.98 | 76 | DN125 | 2900 × 1830 × 2000 | 4,800 kg |
| CZ-SLTLT-132T | 132 | 175 | 4 bar17.34-38.545 bar15.69-34.87 | 74 | DN125 | 2820 × 1730 × 2100 | 5,000 kg |
| CZ-SLTLS-160S | 160 | 215 | 3 bar18.66-41.484 bar16.38-36.45 bar14.55-32.34 | 76 | DN150 | 3500 × 2030 × 2230 | 4,800 kg |
| CZ-SLTLT-160T | 160 | 215 | 4 bar20.16-44.85 bar18.38-40.85 | 76 | DN125 | 3450 × 2000 × 2050 | 5,900 kg |
| CZ-SLTLS-185S | 185 | 250 | 3 bar19.81-44.034 bar18.45-415 bar16.37-36.38 | 76 | DN200 | 4250 × 2280 × 2550 | 7,000 kg |
| CZ-SLTLT-185T | 185 | 250 | 4 bar23.54-52.35 bar21.43-47.62 | 76 | DN150 | 3450 × 2000 × 2050 | 5,900 kg |
| CZ-SLTLS-200S | 200 | 270 | 3 bar20.96-46.594 bar19.71-43.815 bar17.86-39.71 | 76 | DN200 | 4250 × 2280 × 2550 | 8,000 kg |
| CZ-SLTLT-200T | 200 | 270 | 4 bar25.81-57.365 bar23.29-51.76 | 80 | DN150 | 3800 × 2250 × 2350 | 7,800 kg |
| CZ-SLTLS-220S | 220 | 294 | 3 bar26.9-59.784 bar22.37-49.735 bar18.47-41.06 | 77 | DN200 | 4250 × 2280 × 2550 | 8,000 kg |
| CZ-SLTLT-220T | 220 | 294 | 4 bar27.9-62.015 bar25.69-57.1 | 80 | DN150 | 3800 × 2250 × 2350 | 8,000 kg |
| CZ-SLTLT-250T | 250 | 335 | 4 bar30.58-67.955 bar29-64.54 | 80 | DN150 | 3800 × 2250 × 2350 | 8,100 kg |
Flows, pressures, noise levels and dimensions recorded model by model on the catalogue sheets.
A screw designed for 3 to 5 bar, not an 8 bar machine turned down: the airend is sized for that operating point, which gives it a much higher flow for the same power. Every bar too many costs about 7% of the energy; producing at 8 bar to consume at 4 throws the difference away.
It targets processes that only need low pressure on a large flow: pneumatic conveying, fermentation, textiles. Wastewater basin aeration, below 1 bar, belongs to the blowers. A network that mixes 7 bar and 4 bar uses is split in two, with one machine per pressure.
A lubricated screw compressor optimised for low pressures (from 3 to 5 bar) rather than the standard 7-13 bar. The rotor profile and the control are calibrated to deliver a large volume of air at moderate pressure, with maximum efficiency over that range.
Compressing to 4 bar rather than 7 bar when the process only needs 4 bar avoids wasting the energy of unnecessary overpressure: each bar saved represents about 7% less energy.
Processes that consume large volumes of air at low pressure: pneumatic conveying, fermentation, blowing, industrial drying, textiles, glassmaking. Wherever a standard compressor would expand its air at a loss.
Designed for 3 to 5 bar
Air-end designed for low pressure, instead of an 8 bar compressor turned down: for the same flow, the air is not compressed higher than it is used.
From 6 to 68 m³/min
Twenty-seven sizes from 22 to 250 kW, from 6.1 to 68 m³/min between 3 and 5 bar, for uses that consume a lot of air at low pressure.
No unnecessary overpressure
Compress only to the pressure required: each bar avoided saves about 7% of energy, according to the US Department of Energy's Sourcebook, over the whole life of the installation.
Lightly loaded bearings
High-capacity bearings working at low load, since the discharge pressure stays low. IP55 motor (IE3 up to 55 kW, IE4 above, IE5 on request), PLC controller with 14 protections.
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