Oil-free rotary

screw compressors

ZR/ZT 55-90 (VSD) (FF)

 Setting the standard in
energy efficiency, safety
and reliability
The shortest route to superior productivity is to minimize operational cost
while maintaining an uninterrupted supply of the right quality of air. The Atlas
Copco Z compressor series is focused on effectively saving energy, ensuring
product safety – only oil-free machines exclude contamination risks for 100%
– and guaranteeing the utmost reliability around the clock. And not just today,
but day after day, year after year, with minimal maintenance cost, few service
interventions and long overhaul intervals.

ZR/ZT 55–90 (FF)

Pioneering the development of oil-free
air technology
The ISO 8573-1 CLASS 0 certification means, zero risk of
our products contaminating the compressed air. This
means we won't damage your company’s hard-won
professional reputation due to oil contamination from our
oil-free products.

Maximum energy efficiency

The ZR/ZT’s superior oil-free screw elements provide the
optimum combination of high Free Air Delivery (FAD) with
the lowest energy consumption. Ample sized cooling, low
pressure drops and an extremely efficient drive train result
in the highest compressor package efficiency.

The most complete package

With the ZR/ZT compressor, Atlas Copco provides a
superior solution without hidden costs. The totally
integrated, ready-to-use package includes internal piping,
coolers, motor, lubrication and control system. The Full
Feature version even integrates an IMD adsorption dryer
for an impeccable end product. Installation is fault-free,
commissioning time is low and no external instrument air
is required. You simply plug and run.

Global presence - local service

Our aftermarket product portfolio is designed to add
maximum value for our customers by ensuring the
optimum availability and reliability of their compressed
air equipment with the lowest possible operating costs.
We deliver this complete service guarantee through our
extensive service organization, maintaining our position
as leader in compressed air.

3
Air Quality
Compressed air is used in a wide variety of manufacturing and commercial operations. Air is generated from the ambient atmosphere
around the compressor and typically would contain contaminants in the form of dust and water which are two naturally occurring
impurities while a third impurity which is oil typically gets added to compressed air due to the compression process. Oil though can
be avoided / eliminated by using our 100% oil free compressors.

100% oil-free compressed air

For over 60 years Atlas Copco has pioneered the development of oil-
free air technology. Resulting in the largest range of air compressors
and blowers within our industry. Through continuous research and
development, we achieved a new milestone, setting the standard for
air purity as the first manufacturer to be awarded ISO 8573-1 CLASS 0
certification. CLASS 0 certification means zero risk of oil
contamination from our products.

Air treatment
Untreated compressed air contains moisture and possibly dirt
particles that can damage your air system and contaminate your
end product. The resulting maintenance costs far exceed air
treatment costs. Atlas Copco believes in effective prevention and
provides a complete range of air treatment solutions to protect
investments, equipment, production processes and end products.

ZR/ZT 55–90 (FF)

ISO 22000
ISO 22000 is a management system for food safety. Atlas Copco is
among a few compressor manufacturers to have their oil free
compressors and related dryers and filters certified for ISO 22000 by
Lloyds Register Quality Assurance.

Avoid downtime
Low quality air heightens the risk of corrosion, which can lower the
life span of production equipment. The air treatment solutions
produce clean air that enhances your system’s reliability, avoiding
costly downtime and production delays.

Compressed air coming into contact with your final products

should not affect their quality. Atlas Copco provides clean, dry air to
protect your production and reputation in the market.

5
Reliability

Oil-free Air Compressor Elements (Class Main drive motor

0) • IP55 TEFC motor protects against dust, chemicals and
• Unique seal design guarantees certified oil-free air humidity
• Superior coating for high durability • Continuous operation under severe ambient conditions
• Cooling jackets to ensure world class compression in
different conditions
Efficient intake air filtration
• 2 stage dust removal system (99.9% for 3 micron)
• High grade protection of the compressor

ZR/ZT 55–90 (FF)

Highly reliable coolers Complete Plug-and-play package
• Compact design with low approach temperature • All in one solution: fault free installation, easy
• Low thermal stresses ensure long lifetime commissioning and quick start up
• Reliable water separation ensures low water carry over to • Includes internal piping, coolers, motor, drive,
downstream equipment lubrication and control system
• Stainless steel water coolers designed for durability and
easy serviceability

Sound proof design

• Silenced canopy ensures optimal working conditions for
Reliable load/unload regulation
everyone in the immediate environment
• No external air supply needed • Optimized internal ducting and integrated pulsation
• Mechanical interlock of inlet and blow-off valve damper to reduce noise level
• Low unload power

Ease of maintenance
Advanced touch screen monitoring
• Minimal service time with service parts grouped together
system for ease of access
• User friendly Elektronikon Touch with enhanced • All components are designed for serviceability and
connectivity potential longevity
• Integrated smart algorithms to protect equipment in • Optional service plans available to extend warranty
harsh conditions
• Including warning indications, maintenance scheduling
and online visualization of the machine’s condition
Smart Energy Recovery Valve
• The Energy Recovery option on ZR has improved
regulation to ensure stable water temperature at the
required level for your processes.

7
Reliability

Oil-free Air Compressor Elements (Class Main drive motor

0) • IP55 TEFC motor protects against dust, chemicals and
• Unique seal design guarantees certified oil-free air humidity
• Superior coating for high durability • Continuous operation under severe ambient conditions
• Cooling jackets to ensure world class compression in
different conditions
Efficient intake air filtration
• 2 stage dust removal system (99.9% for 3 micron)
• High grade protection of the compressor

ZR/ZT 55–90 (FF)

Highly reliable coolers Complete Plug-and-play package
• Compact design with low approach temperature • All in one solution: fault free installation, easy
• Low thermal stresses ensure long lifetime commissioning and quick start up
• Reliable water separation ensures low water carry over to • Includes internal piping, coolers, motor, drive,
downstream equipment lubrication and control system
• Stainless steel water coolers designed for durability and
easy serviceability

Sound proof design

• Silenced canopy ensures optimal working conditions for
Reliable load/unload regulation
everyone in the immediate environment
• No external air supply needed • Optimized internal ducting and integrated pulsation
• Mechanical interlock of inlet and blow-off valve damper to reduce noise level
• Low unload power

Ease of maintenance
Advanced touch screen monitoring
• Minimal service time with service parts grouped together
system for ease of access
• User friendly Elektronikon Touch with enhanced • All components are designed for serviceability and
connectivity potential longevity
• Integrated smart algorithms to protect equipment in • Optional service plans available to extend warranty
harsh conditions
• Including warning indications, maintenance scheduling
and online visualization of the machine’s condition
Integrated dryer
With the ZR/ZT you have the option to include a dryer.
IMD dryer with Silicone free rotor.

9
Efficiency
Design & control algorithms for optimal efficiency

Components designed for efficiency

1. Compressor elements with superior coating, optimized design
and low loss bearings and seals ensure highest efficiency.

2. Efficient intake filtration for minimum losses and low pressure

drop.

3. Coolers are designed for efficiency with low pressure drop and
low air approach temperature, ensuring coolest possible running
conditions.

4. Our fixed speed machines come with IE4 super premium

efficiency motors, giving you extra energy savings, every hour the
machine runs.

VSD machines are equipped with IE3 premium efficiency motors, in

combination with our highly efficient in-house designed Neos
frequency converter.

With machines typically running 4000 to 8000 hours per year, again
a major contributor to energy savings.

VSD savings
Atlas Copco's VSD technology closely follows the air demand by
automatically adjusting the motor speed. This results in large energy
savings of up to 35%. The Life Cycle Cost of a compressor can be cut
by an average of 22%. In addition, lowered system pressure with VSD
minimizes energy use across your production dramatically.

Legend
42% = Energy
35% = Energy savings with VSD
12% = Investment
11% = Maintenance

ZR/ZT 55–90 (FF)

 Variable Speed Drive (VSD)
Over 80% of a compressor’s lifecycle cost is taken up by the energy
it consumes. Moreover, the generation of compressed air can
account for more than 40% of a plant’s total electricity bill. To cut
your energy costs, Atlas Copco pioneered Variable Speed Drive
(VSD) technology in the compressed air industry. VSD leads to
major energy savings, while protecting the environment for future
generations. Thanks to continual investments in this technology,
Atlas Copco offers the widest range of integrated VSD compressors
on the market.

Legend
A = Losses
B = Speed
1 = Total losses traditional element
2 = Total losses AC element

SMARTLINK
Monitor your compressed air installation with SMARTLINK
Knowing the status of your compressed air equipment at all times is
the surest way to achieve optimal efficiency and maximum
availability.

Go for energy efficiency

Customized reports on the energy efficiency of your compressor
room.

Increase uptime
All components are replaced on time, ensuring maximum uptime.

Save money
Early warnings avoid breakdowns and production loss.
 11

Energy Recovery
You can turn your compressor into an energy source. Our ZR
compressors equipped with Energy Recovery can help you achieve
your goals in becoming carbon neutral.
Compressed air is one of the most important utilities for the
industry. It is also one of the largest consumers of energy. Up to
94% of the electrical energy is converted into compression heat.
Without energy recovery, this heat is lost into the atmosphere via
the cooling system and radiation.
You can use hot water recovered from the compressed air system
for sanitary purposes and space heating. But it is particularly
suitable for process applications. Using the hot water as boiler pre-
feed or directly in processes requiring 70 to 90°C can save you costly
energy sources such as natural gas and heating oil.
 Advanced control algorithms
The Elektronikon compressor monitoring system saves energy by
using advanced control algorithms:
Delayed Second Stop (DSS): in traditional fixed speed machines
(load/unload), when a compressor reaches the unload pressure, the
machine will be kept running in unload for a fixed time, to prevent
too frequent starting and causing the electrical motor to overheat.
Our sophisticated Delayed Second Stop (DSS) will take the running
conditions of the machine into account and will allow the machine to
stop if no frequent motor starts preceded. This will generate major
savings compared to traditional load/unload compressors.
Timer Functions: stop your machines when no air is needed. Often,
machines are kept running over night and during weekends, even if
there is no need for compressed air during these times. The timer
function on our compressors can easily fix this.
Dual pressure band: even if compressed air is needed during nights
and weekends, often, the required pressure is lower during these
times. Implementing a dual pressure band with lower settings during
nights and weekends will save loads of energy.

Dual set-point and automatic stop

Most production processes create fluctuating levels of demand
which, in turn, can create energy waste in low use periods. Using
the Elektronikon® unit controller, you can manually or automatically
switch between two different setpoints to optimize energy use and
reduce costs at low use times. In addition, the sophisticated
algorithm runs the drive motor only when needed. As the desired
setpoint is maintained while the drive motor’s run time is
minimized, energy consumption is kept to a minimum.

Multiple Machine Control

Any installation with 3 or more machines will benefit from our
advanced controller, the Optimizer 4.0. It will control your installation
in a more efficient way than the individual machines with individual
settings can.

ZR/ZT 55–90 (FF)

smart AIR solutions
Only a complete compressed air system is an energy efficient and reliable solution that delivers the correct compressed air quality.
That is why we call our solutions smart AIR solutions.

13
 3. Variable Speed Drive (VSD)
compressors
Compressed air demand of most applications varies
widely. Adding one or multiple VSD compressors to the
installation will greatly help to improve energy efficiency
of the total installation, stability of compressed air
pressure and reliability, thanks to more stable regime of
each machine.

1. Central controllers 4. Ventilation

Having a central controller reduces the average pressure Compressors generate heat. Adequate evacuation of this
band. heat will ensure favorable working conditions for
It also reduces the operating pressure of your machines. compressors and dryers alike.
• By reducing the pressure by 1 bar (or 14.5 psi), your
energy usage lowers by 7%.
• By reducing the pressure by 1 bar (or 14.5 psi) decreases
air leakages by 13%.
5. Air receiver
Multiple embedded functions in the Optimizer 4.0 in Even with a Variable Speed Drive compressor, having an
which pressure, capacity and speed can be regulated. appropriately sized buffer tank for compressed air will
help smoothening the variation in demand and allow
Legend compressors to work in more stable operating conditions,
A = Net pressure thus helping both energy efficiency and reliability.
B = Average pressure
C = Min. system pressure

6. Compressed air dryers

2. Energy efficient and reliable The correct choice of dryer technology corresponding to
compressors the compressed air quality requirements is detrimental to
a reliable and energy efficient compressed air installation.
All smart AIR solutions start with picking the correct The choice for integrated dryers – our full feature concept
components in the correct combination. Choosing energy – will have additional benefits, reducing installation cost,
efficient compressors, paying special attention to the mix time and complexity, having dryers controlled together
of compressors will be a major contributor to a smart AIR with the compressors, reducing connecting pipes, hence
solution. the chance of leakages and extra pressure drops. And look
Our sound proof design contributes to a better working at the major space saving full feature machines can bring.
environment around the compressors. Smart AIR solutions have impact on every aspect of your
Our compressors have been designed with maintenance compressed air installation.
in mind, reducing the downtime of machines and
improving availability of compressed air.

7. Compressed air filters

Also the correct filter grade in correspondence with air
quality requirements will be an important contributor in a
smart AIR solution. This goes hand in hand with correct
maintenance of the filters, as incorrectly maintained filters
will jeopardize both the reliability of your installation as
the energy efficiency.

ZR/ZT 55–90 (FF)

smart AIR solutions
A compressor is only one component in the bigger picture of a
smart AIR solution. Only a complete compressed air system is an
energy-efficient solution. We designed a range of class-leading
compressed air products, fully optimized to work better together. A
smart AIR solution is the most efficient and reliable combination of
a compressor with our air and gas equipment. This solution can
include dryers, filters, controllers, energy recovery systems,
nitrogen or oxygen generators, air receivers, coolers or boosters
specified to your needs.

In case you have multiple compressors, the combination of

machines is important for the complete system efficiency. And if
you have 3 or more compressors, a central controller will control
your compressed air system in a better and smarter way than what
they can do with their individual controllers.

15
Services
Properly caring for your air compressor lowers operating costs and minimizes the risk for unplanned breakdowns or production stops.
Atlas Copco offers energy efficiency checks, service, repairs, spare parts and maintenance plans for all air compressors. Entrust your
servicing to our experts and ensure your business continues to run efficiently.

Total Responsibility Plan

Complete compressor care
On-time maintenance by expert service engineers.

Total risk coverage

We take care of all your compressor maintenance,
upgrades, repairs and even breakdowns for an all-inclusive
price

Ultimate efficiency
Fitting the latest drive line components gives you as-new
levels of compressor efficiency and reliability

AIRnet
AIRnet is a piping solution that guarantees operational
excellence for compressed air, vacuum, nitrogen and other
inert gas applications. Available in aluminium and stainless
steel.

Fast, easy and reliable

AIRnet Aluminium is the most effective solution for your
air or gas network. Its fast and easy installation gets your
operations up and running in record time. AIRnet is leak-
proof and corrosion-free. Its pipes and fittings come with a
10-year warranty.

Safe, Solid and Clean

AIRnet Stainless Steel piping system ensures 100% oil free
air delivery from the generation to the point of use, in
compliance with the highest quality standards.

ZR/ZT 55–90 (FF)

AIRScan
Audit your compressed air installation with AIRScan
AIRScan offers a reliable analysis and well-founded
recommendations to improve your energy efficiency.

Go for energy efficiency

AIRScan offers a reliable analysis and actionable insights for
energy efficiency improvements.

Save energy: up to 30 % of your costs

Our unique compressor audit software simulates various
configurations of your compressed air installation. This
allows us to provide realistic projections on potential
energy savings.

Clear report
An AIRScan report provides a summary for decision makers,
as well as an in-depth evaluation of problems and solutions
for your technicians.

17
Optimize your system
With the ZR/ZT, Atlas Copco provides an all-in-one standard package incorporating the latest technology in a built to-last design. To
further optimize your ZR/ZT's performance or to simply tailor it to your specific production environment, optional features are
available.

Options

ZR/ZT 55-90 (VSD)

Monitoring & Protection bundle (Anti-Condensation heaters / SPM equipment / PT 1000 in the windings & bearings) •
Integrated SMARTLINK •
Kit for purge of dry air during standstill •
Silicone-free rotor for dryer Standard scope
Anchor pads •
Wooden case protection packaging •
High ambient temperature version* •
Test certificate •
Witnessed performance test •
IT Network (VSD) •
Energy recovery •
Teflon free •
MD heater •
Hot air •
Water shutoff valve •

•: Optional

(*) Maximum intake/cooling air temperature is 50°C/122 °F for HAT versions.

Please note the availability of the option depends on the chosen configuration.

ZR/ZT 55–90 (FF)

Flowchart
Process flow, oil flow and cooling flow - step by step

1. Filtration & first compression 3. Cooling & drying

The light blue flow represents the air. Air is drawn into the The air at the outlet of the high pressure stage is split in
compressor through the inlet filter where the air is two parts. One part goes via the pulsation damper with
cleaned. Then passes through the throttle valve with integrated check valve to the after-cooler where it is
integrated blow off valve that takes care of the load cooled down and moisture is separated and evacuated. A
unload regulation. second part goes directly to the regeneration area of the
heat compression MD dryer.
In the first compression stage the air pressure is raised to
the intermediate pressure after which the air is cooled In the regeneration area of the dryer the hot air
down in the inter-cooler. regenerates the adsorption drum after which it passes
through the regeneration cooler where it is cooled down
and moisture is separated and evacuated. The cold air
coming from the regeneration section is then mixed with
2. Cooling & second compression the cold air from the after-cooler in the nozzle-ejector
After the inter-cooler the air passes through a moisture system before passing through the drying section of the
separation system before entering the high pressure adsorption drum where the moisture is removed. Dry air
stage. In the high pressure stage the pressure is brought to leaves the compressor through the outlet connection
the final pressure. flanges.

19
 4. Oil flow
The yellow flow is the oil path within the
compressor where the oil pump sucks oil from the oil
sump and pumps it through the oil cooler and a high
efficiency filter to give cool clean oil to the bearings and
the gears; then the oil flows back to the gear casing.

ZR/ZT 55–90 (FF)

Technical specifications
Data from the ZRZT 55-90 (VSD) (FF)

ZR 55-90 (FF)

Working pressure (1) Free Air Delivery FAD (2) Installed motor power Noise level (3)
Type
bar(e) psig l/s m³/min cfm kW/HP dB(A)
50 Hz
Minimum 7,5 100 169.9 10.2 360.2 71
ZR 55 Effective 8,6 125 156.3 9.4 332 55/75 71
Maximum 10 145 140.7 8.4 296.6 74
Minimum 7,5 100 224.6 13.5 476.7 69
ZR 75 Effective 8,6 125 214.7 12.9 455.6 75/100 69
Maximum 10 145 204.8 12.3 434.4 74
Minimum 7,5 100 267.2 16.0 565.0 72
ZR 90 Effective 8,6 125 250.7 15.0 529.7 90/120 72
Maximum 10 145 263.4 14.2 501.5 74
60 Hz
Effective 8,6 125 161.7 9.7 342.6 70
ZR 55 55/75
Maximum 10,4 150 142.7 8.6 303.7 74
Effective 8,6 125 226.1 13.6 480.3 70
ZR 75 75/100
Maximum 10,4 150 200.3 12.0 423.8 74
Effective 8,6 125 262.1 15.7 554.4 71
ZR 90 90/120
Maximum 10,4 150 240.8 14.5 512.1 74

ZR 75-90 VSD (FF)

Working pressure (1) Free Air Delivery FAD (2) Installed motor power Noise level
Type
bar(e) psig l/s m³/min cfm kW/HP dB(A)
Minimum 4 58 75.6-239.5 4.6-14.4 160.2-507.5
ZR 75 VSD - 8.6 Effective 7 100 74.7-229.4 4.48-13.8 158.2-486.1 70
Maximum 8.6 125 74.1-208.6 4.4-12.5 157-442
75/100
Minimum 4 87 82.6-239.2 4.3-14.35 175-506.8
ZR 75 VSD - 10.4 Effective 9 130 81.7-202.9 5.0-12.2 173.1-429.9 74
Maximum 10.4 150 81.3-184.6 4.9-11.1 172.3-391.1
Minimum 6 58 75.1-297.2 4.51-17.8 159.1-629.7
ZR 90 VSD - 8.6 Effective 7 100 74.1-282.5 4.4-16.9 157-598.6 71
Maximum 8.6 125 73.6-258.1 4.42-15.5 155.9-546.9
90/120
Minimum 6 87 76.5-292.9 4.6-17.6 162.1-620.6
ZR 90 VSD - 10.4 Effective 9 130 75.5-250.5 4.53-15 160-530.8 74
Maximum 10.4 150 75.0-229.2 4.5-13.7 158.9-485.6

21
ZT 55-90 (FF)

Working pressure (1) Free Air Delivery FAD (2) Installed Motor Power Noise level (3)
Type
bar(e) psig l/s m³/min cfm kW/HP dB(A)
50 Hz
Minimum 7,5 100 166.3 10 352.4 76
ZT 55 Effective 8,6 125 153.0 9.2 324.2 55/75 75
Maximum 10 145 137.4 8.2 291.1 76
Minimum 7,5 100 221.2 13.3 468.7 78
ZT 75 Effective 8,6 125 211.4 12.7 447.9 75/100 78
Maximum 10 145 201.5 12.1 427 74
Minimum 7,5 100 263.9 15.8 559.2 79
ZT 90 Effective 8,6 125 247.4 14.8 524.2 90/120 77
Maximum 10 145 233 14 493.7 79
60 Hz
Effective 8,6 125 158.4 9.5 335.6 77
ZT 55 55/75
Maximum 10 150 139.3 8.4 295.1 79
Effective 8,6 125 222.8 13.4 472.1 79
ZT 75 75/100
Maximum 10,4 150 197.0 11.8 417.4 76
Effective 8,6 125 258.7 15.5 548.1 78
ZT 90 90/120
Maximum 10,4 150 237.4 14.2 503 78

ZT 75-90 VSD (FF)

Type Working Pressure (1) Free Air Delivery (A) Installed Motor Power Noise level (3)
bar(e) psig l/s m³/min cfm kW/Hp dB(A)
Minimum 4 58 72.2-236.1 4.33-14.2 153-500
ZT 75 VSD - 8.6 Effective 7 100 71.2-226.0 4.27-13.6 150.9-478.9 78
Maximum 8.6 125 70.7-205.2 4.24-12.3 149.8-434.8
75/100
Minimum 6 87 79.2-235.8 4.8-14.1 167.8-499.6
ZT 75 VSD - 10.4 Effective 9 130 78.2-199.6 4.7-12 165.7-422.6 76
Maximum 10.4 150 77.8-181.3 4.67-10.9 164.8-384.1
Minimum 4 58 71.7-293.9 4.3-17.6 151.9-622.7
ZT 90 VSD - 8.6 Effective 7 100 70.6-279.1 4.24-16.7 149.6-591.4 78
Maximum 8.6 125 70.1-254.7 4.2-15.3 148.5-539.7
90/120
Minimum 6 87 73.0-289.5 4.4-17.4 154.7-613.4
ZT 90 VSD - 10.4 Effective 9 130 72.0-247-1 4.3-14.8 152.6-523.6 77
Maximum 10.4 150 71.5-225.7 4.29-13.5 151.5-478.2

ZR/ZT 55–90 (FF)

Notes

23
 Atlas Copco AB

Reg. no: 556014-2720

www.atlascopco.com
Phone: +46 8 743 80 00
(publ) SE-105 23 Stockholm, Sweden
2935 0724 00 © 2021, Atlas Copco Airpower NV, Belgium. All rights reserved. Designs and specifications are subject to change without notice or obligation. Read all safety instructions in the manual before
usage.