Atlas Copco Oil-Sealed Screw Pumps

Most rough vacuum systems run a fixed-speed pump at full power, even when the plant only needs a fraction of that capacity. Atlas Copco GHS VSD+ oil-sealed screw pumps change that. A variable speed drive adjusts motor speed to the vacuum actually required, which can cut energy use substantially on plants with changing demand. At Provac Sales, we supply the full GHS VSD+ range and offer repair and rebuild service for Atlas Copco vacuum equipment.

GHS 350 to 900 VSD+ (Point-of-Use and Production Area)

• Atlas Copco GHS 350VSD+
• Atlas Copco GHS 585VSD+, about 330 CFM
• Atlas Copco GHS 730VSD+
• Atlas Copco GHS 900VSD+

GHS 1300 to 5400 VSD+ (Central Vacuum and Utility Rooms)

• Atlas Copco GHS 1300VSD+ and GHS 1600VSD+
• Atlas Copco GHS 1900VSD+
• Atlas Copco GHS 3800VSD+, about 2,253 CFM
• Atlas Copco GHS 4600VSD+ and GHS 5400VSD+

Across the range, nominal displacement runs from about 240 to 2,945 CFM, with shaft power from 7.5 to 120 hp. Pricing and lead time are confirmed on inquiry, and other configurations are available on request.

How an Oil-Sealed Screw Pump Works

A GHS pump uses two intermeshing screw rotors in a single compression stage. Oil is injected into the compression element to seal the clearances, cool the gas and lubricate the rotors. Unlike a rotary vane pump, there are no vanes sliding against a housing, so there are fewer wear parts and the pump can run long hours with stable performance.

After compression, the oil and air mixture passes through a multi-stage separator. Atlas Copco's patented oil retention design keeps oil carry-over below 3 mg/m³, so exhaust air is clean and oil consumption stays low.

Key Specifications

• Ultimate pressure: 0.26 Torr (0.35 mbar)
• Nominal displacement: about 240 to 2,945 CFM (400 to 5,004 m³/h)
• Shaft power: 7.5 to 120 hp (5.5 to 90 kW)
• IE3 premium efficiency motors
• Integrated Elektronikon controller, drive cubicle and sound-insulated canopy
• Turbo versions for fast cycling and Humid versions for higher water vapor loads

Why Variable Speed Matters

Vacuum demand in a real plant rarely stays constant. Packaging lines start and stop, shifts change and machines cycle. A fixed-speed pump keeps running at full power and wastes energy whenever demand falls. A GHS VSD+ pump reads the system pressure and slows the motor to hold the set point. Atlas Copco reports energy savings of up to 50 percent or more against fixed-speed technologies in most applications, based on its energy audits.

Other practical benefits include:

• Stable vacuum level at the set point, even as demand changes
• Lower noise when running below full speed
• Less stress on the motor and drive train from frequent starts
• On GHS 1300 to 5400 models, an optional energy recovery system that can capture a large share of the input power as usable heat

GHS VSD+ vs Rotary Vane Pumps

For small, single-machine applications, an oil-sealed rotary vane pump such as an Atlas Copco GVS is often the simpler and less expensive option. GHS VSD+ screw pumps make the most sense when:

• One pump serves several machines or a central vacuum network
• The pump runs long hours with varying demand
• Energy cost is a significant part of operating cost
• You want to replace several vane pumps with one central system
• Low oil carry-over and quiet running are important

Compare options in our Atlas Copco vane pumps collection, or ask us to review your current setup.

Applications

• Food and meat packaging, including thermoforming and tray sealing
• Plastics extrusion, thermoforming and degassing
• Glass and bottling
• Canning
• Woodworking and CNC hold-down
• Printing and paper
• Electronics manufacturing
• Central plant vacuum systems

How to Size a GHS VSD+ Pump

Before ordering, gather:

• Required working pressure at the machines
• Total flow demand, ideally logged over a typical shift
• Number of machines and how often they cycle
• Process vapors, especially water vapor, which may call for a Humid version
• Supply voltage and available electrical capacity
• Installation space, ambient temperature and ventilation
• Whether heat recovery would be useful in your facility

Because the VSD+ adjusts output, a correctly sized pump will spend most of its time in the middle of its speed range, where it is most efficient.

Consolidating Several Pumps Into One Central System

Many plants start with a separate vane pump on each machine. Over time, that adds up to many motors, many oil changes and a lot of heat and noise on the production floor. A central GHS VSD+ system can replace several point-of-use pumps with one variable speed unit in a utility room, connected to the machines through a vacuum header and receiver tank. The VSD+ drive follows the combined demand, so the system runs efficiently whether one machine is running or all of them are. Maintenance is concentrated in one place, and the production floor becomes quieter and cooler.

Installation Tips

• Install the pump in a clean, well-ventilated space and respect the clearances in the manual
• Size the vacuum header and receiver for the combined flow so line losses stay low
• Fit isolation valves at each machine so one line can be serviced without shutting down the system
• Route the exhaust outdoors or to a suitable extraction point
• Check supply voltage, cable size and protection against the drive's rated input
• Program the pressure set point on the Elektronikon controller and log the first week of operation

Maintenance Tips

• Check the oil level at the sight glass with the pump stopped
• Change oil, oil filter and separator elements at the intervals the Elektronikon controller indicates
• Keep the inlet filter clean, especially in dusty or fibrous environments
• Keep cooling air paths and coolers free of dust
• Use the oil specified for your model and process
• Review controller alarms and service warnings promptly

Find pump oil in our vacuum fluids and greases collection.

Atlas Copco Screw Pump Service

Provac Sales repairs and rebuilds Atlas Copco vacuum pumps. Before shipping a GHS pump for service, submit an RMA request, complete the contamination data sheet and drain the oil. Include the model, serial number, run hours and any controller fault codes. Learn more on our pump repair page.

Atlas Copco GHS VSD+ Pumps FAQ

1. What is the ultimate pressure of an Atlas Copco GHS VSD+ pump?

The GHS VSD+ series is rated at an ultimate pressure of 0.26 Torr (0.35 mbar). Working pressure and pumping speed at that pressure depend on the model.

2. How much energy can a GHS VSD+ pump save?

Atlas Copco reports savings of up to 50 percent or more compared with fixed-speed pumps in most applications. Actual savings depend on how much your vacuum demand varies during the day.

3. What is the difference between GHS 350-900 and GHS 1300-5400 models?

GHS 350 to 900 VSD+ pumps are compact units designed for production areas and point-of-use duty. GHS 1300 to 5400 VSD+ pumps are larger units usually installed in utility rooms for central vacuum, with an optional energy recovery system.

4. What are the Turbo and Humid versions?

Turbo versions are optimized for fast cycling applications such as packaging. Humid versions are designed to handle higher water vapor loads. Tell us your process and we will recommend the right version.

5. Is a GHS screw pump oil-free?

No. GHS pumps are oil-sealed. Oil seals and cools the screw element, and a separator keeps oil carry-over below 3 mg/m³. For an oil-free compression chamber, see the Atlas Copco DHS dry screw range.

Request a Quote on Atlas Copco GHS VSD+ Pumps

Send us your working pressure, flow demand, number of machines and supply voltage. We will recommend the right GHS VSD+ model and version, confirm lead time, or quote service on your existing pump. Contact us or call 831-462-8900.