Rotary Screw Compressor FAQ

What is a rotary screw air compressor?

A rotary screw compressor uses two meshing helical rotors to compress air continuously. Unlike piston compressors, which work in strokes, screw compressors provide a constant flow of air, making them ideal for workshops and factories that run for many hours per day.

When should I choose a screw compressor instead of a piston?

Choose a screw compressor when you need more than a few hours of compressed air per day, when your tools or machinery must not see pressure drops, or when noise and efficiency are important. Piston units are fine for light, intermittent use; screw units are built for continuous or high duty applications.

How long does a rotary screw compressor last?

With correct servicing and clean intake conditions, a quality screw compressor can deliver 50,000 to 80,000 running hours or more over its life. The air end is the heart of the machine — protecting it with the right oil and filters is critical to longevity.

What is the difference between TryComp and Budget Air?

TryComp is our premium range, engineered for continuous industrial duty — factories, production plants and multi-shift operations where uptime and efficiency are non-negotiable. Budget Air is our value range for workshops, tyre centres and light-to-medium industry. Both ranges run from 7.5kW to 75kW and are backed by The Titan Emporium's service network.

What information do you need to size a compressor?

We start with:

• The tools and machines you want to run.
• Your working pressure (bar) at the point of use.
• Operating hours per day and days per week.
• Your available electrical supply and kVA limits.
• Any air quality requirements (dry, oil-free, food-grade, etc.).

Based on this, we recommend a TryComp or Budget Air model and the right air treatment package.

What is VSD and do I need it?

A Variable Speed Drive (VSD) compressor adjusts its motor speed to match your actual air demand in real time. When correctly applied, VSD can reduce energy consumption by up to 30–35%. It delivers the greatest benefit where demand varies significantly during the day — for example, between production shifts and idle periods.

What power range do you supply?

This site covers 7.5kW to 75kW in both TryComp and Budget Air ranges. Larger units and custom configurations are available on request through The Titan Emporium's broader engineering capability.

Do I really need an air dryer?

Yes, in most industrial environments. Compressed air always contains moisture. Without a dryer, this moisture condenses in pipes, tools and equipment, causing rust, blockages, product defects and higher maintenance costs. A correctly sized dryer protects your compressor investment and downstream equipment.

What is the difference between refrigeration and desiccant dryers?

Refrigeration dryers are common for general industry and achieve dew points suited to most workshop and factory conditions — typically +3°C pressure dew point. Desiccant dryers provide much lower dew points (down to -40°C or lower) and are used where very dry air is needed, for example certain food, pharmaceutical or high-altitude outdoor applications.

How often should I service my screw compressor?

• Basic checks and top-ups: every few weeks.
• Filter and oil changes: typically around 2,000 running hours.
• More extensive services: based on OEM recommendations and oil type.

Our team can put together a planned maintenance schedule based on your hours and risk profile.

What are the biggest drivers of operating cost?

Electricity is usually the single largest cost over the life of a compressor — often 70–80% of total lifetime cost. Correct sizing, minimising air leaks in your system, using VSD where appropriate, and maintaining intake filtration all reduce energy spend. Regular servicing prevents small issues from becoming large failures.

What is an oil injected screw compressor?

An oil injected screw compressor uses oil to seal, cool and lubricate the rotors inside the air end. This is the most common type for general industry, workshops and manufacturing. The oil is separated from the compressed air downstream before it reaches your tools and equipment. The vast majority of our TryComp and Budget Air units are oil injected rotary screw compressors.

What is an oil free screw compressor and do I need one?

An oil free screw compressor uses specially coated rotors that do not require oil for lubrication. The compressed air produced contains no oil carry-over — essential for food processing, pharmaceuticals, electronics and certain medical applications. Oil free units are significantly more expensive than oil injected alternatives. For most workshops and factories, a well-maintained oil injected compressor with quality downstream filtration achieves the air quality required at a much lower cost.

Belt driven vs direct drive screw compressor — which is better?

A belt driven screw compressor connects the motor to the air end via belts and pulleys, allowing some speed adjustment and easier maintenance. A direct drive screw compressor couples the motor directly to the air end — more compact and efficient with fewer wear components. Both types are available in our TryComp and Budget Air ranges depending on the model and configuration selected.

What is a VSD / variable speed screw compressor?

A VSD screw compressor (Variable Speed Drive) uses an inverter to vary the motor speed in real time, matching compressed air output to actual demand. Unlike a fixed speed unit that runs at full speed and vents excess air, a variable speed screw compressor ramps up and down continuously — reducing energy consumption by 20–35% in applications where demand fluctuates. VSD is most beneficial in operations with variable production loads, shift changes or seasonal demand swings.

What is the difference between a rotary screw compressor and a piston compressor?

A rotary screw air compressor delivers continuous, smooth airflow using interlocking helical rotors — suitable for 100% duty cycle and multi-shift production. A piston (reciprocating) compressor delivers air in pulses and is typically limited to 60–70% duty cycle. For any application running more than a few hours per day, a screw air compressor offers significantly lower total cost of ownership through energy efficiency, lower maintenance frequency and longer service life.

Do you offer site visits and assessments?

Yes. Through The Titan Emporium we arrange site visits in all major South African regions. For SADC clients we support remotely or via partner networks. We assess your current installation, risks and upgrade opportunities and produce a recommendation based on real site conditions — not just catalogue data.

Which regions do you cover?

We support customers across South Africa — Johannesburg, Durban, Cape Town, Pretoria, Nelspruit, Port Elizabeth, Bloemfontein — and export into Namibia, Botswana, Zambia, Mozambique, Zimbabwe and other SADC markets on request. View all locations →