What are the 8 types of compressors, and how do they differ Compressors play a critical role in various industries, from refrigeration to manufacturing, each offering unique advantages and applications. We’ll explore eight main types of compressors: centrifugal, piston, screw, vane, scroll, liquid ring, rolling piston, and sliding vane.
1. Centrifugal Compressors
Centrifugal compressors, also known as radial compressors, are a type of dynamic compressor that uses a rotating impeller to add velocity to gases, thereby increasing their pressure. Widely used in low-pressure air separation systems, they are gradually replacing piston compressors.
Working Principle
Centrifugal compressors work by accelerating gas through a set of rotating blades called impellers, which increase the gas’s kinetic energy. This energy is then converted into pressure in the diffuser. The gas moves through multiple stages (or impellers), each boosting its pressure further. Picture it like a fan blowing air into another fan, increasing the airflow power after each stage.
The pressure rise is achieved through two mechanisms: the centrifugal force exerted on the gas as it is flung outwards from the impeller and the expansion of gas as it moves through the diffuser.
Advantages
High flow rates with continuous, pulsation-free gas discharge.
High operational speeds and no need for lubrication inside the compressor.
Efficient sealing with minimal leakage.
Can be scaled up easily, making them suitable for large-scale operations.
Few moving parts lead to low maintenance.
Disadvantages
Limited adaptability to changes in gas properties and operational conditions.
High internal flow velocities can result in significant friction losses.
Susceptibility to surge conditions, which can be damaging to the compressor.
Applications
Centrifugal compressors are ideal for high-flow, low-to-medium pressure scenarios such as HVAC systems, air separation, and large refrigeration units.
2. Piston Compressors
Working Principle
Piston compressors, or reciprocating compressors is one type of positive displacement compressors, operate by moving a piston back and forth within a cylinder. As the piston moves down, the cylinder’s volume increases, allowing gas to flow in through an intake valve. When the piston moves up, the volume decreases, compressing the gas, which is then forced out through an exhaust valve.
Each movement of the piston completes one cycle, which includes intake, compression, and exhaust phases.
Advantages
Wide pressure range; piston compressors can achieve high pressures even with small gas volumes.
High thermal efficiency, resulting in lower energy consumption.
Flexible in terms of flow and pressure demands, withstanding various pressure ranges and capacities.
Simple construction with easy access to components for repair and maintenance.
Disadvantages
Bulky and heavy, limiting their portability.
Complex structure with many moving parts, which increases the need for maintenance.
Intermittent gas discharge causes pressure pulsations, leading to vibration and noise.
Applications
Piston compressors are prevalent in small to medium-sized refrigeration systems and are commonly used in industries that require high pressures.
3. Screw Compressors
Working Principle
Screw compressors employ two interlocking helical rotors that rotate in opposite directions. As the rotors spin, gas is trapped in pockets between the rotors and the compressor housing. This gas is then compressed as the volume between the rotors decreases, forcing the gas toward the discharge end.
Advantages
Fewer moving parts, leading to higher reliability and a long operational life, with maintenance intervals of up to 40,000–80,000 hours.
Smooth, continuous gas flow with little vibration, making them suitable for high-speed applications.
High efficiency over a wide range of operating conditions.
Strong adaptability to varying pressure demands without sacrificing efficiency.
Disadvantages
Noisy, requiring soundproofing in many settings.
Requires additional equipment, such as oil separators and coolers, to handle lubrication and heat.
Applications
Screw compressors are extensively used in large-scale air conditioning and refrigeration systems, as well as in industries requiring high volumes of compressed gas, like petrochemicals and food processing.
4. Sliding Vane Compressors
Working Principle
In sliding vane compressors, a rotor with multiple vanes mounted eccentrically inside a cylindrical chamber rotates. As the rotor turns, the vanes slide in and out of the rotor’s slots, maintaining contact with the chamber’s inner walls. This mechanism forms several small, sealed chambers that progressively decrease in size, compressing the gas trapped inside.
Advantages
Simple design and ease of manufacture.
Nearly balanced operation with minimal vibration, requiring little to no foundation.
Multiple vanes working simultaneously provide smooth gas flow and reduce pressure pulsations.
Disadvantages
Significant mechanical friction between the vanes and the cylinder, resulting in lower efficiency compared to other compressor types.
Sliding vanes wear out over time, necessitating regular replacement and maintenance.
Less efficient than other types, especially in larger systems.
Applications
Sliding vane compressors are commonly used in small air compressors and refrigeration systems and various air compression applications in the chemical and food industries.
5. Rolling Rotor Compressors
Rolling rotor compressors are widely used in household appliances such as refrigerators and air conditioners. They are compact, efficient, and produce minimal vibration, making them ideal for small-scale cooling applications.
Advantages
Simple structure with few components, leading to higher reliability.
Fewer wear-prone parts, ensuring a longer operational life with minimal maintenance.
Continuous gas compression, which enhances the energy efficiency.
Disadvantages
High precision in manufacturing is required to maintain sealing, making production more costly.
Friction between the rotor and the cylinder leads to wear and limits the machine’s lifespan.
Applications
These compressors are predominantly found in household refrigerators, small air conditioners, and medium-sized cold storage units.
6. Scroll Compressors
Working Principle
Scroll compressors consist of two spiral-shaped scrolls. One scroll remains stationary, while the other orbits around it, trapping and compressing gas between the scrolls. This process is highly efficient and results in continuous gas compression with minimal vibration.
Advantages
Low leakage due to the small pressure difference between adjacent chambers.
Smooth operation with minimal torque variations, reducing vibration.
No intake or exhaust valves, improving reliability and reducing noise.
Capable of handling liquid compression due to the scroll’s flexible design.
Disadvantages
High manufacturing precision is necessary, increasing production costs.
Complex sealing structures may lead to challenges in maintaining the system’s integrity over time.
Applications
Scroll compressors are extensively used in air conditioning and refrigeration units, offering a balance between efficiency, size, and reliability.
7. Liquid Ring Compressors
Working Principle
Liquid ring compressors use a rotating impeller within a cylindrical housing filled with liquid, typically water. The liquid forms a ring against the housing due to centrifugal force, creating a series of variable-volume chambers that trap and compress the gas.
Advantages
Efficient cooling due to the direct contact between gas and liquid.
Ideal for compressing gases that are reactive or subject to decomposition at high temperatures.
Simple structure with few moving parts, leading to low maintenance.
Disadvantages
Low efficiency compared to other types of compressors.
Requires a constant supply of cooling liquid, making it unsuitable for dry or remote locations.
Applications
These compressors are used in industries requiring compression of gases such as acetylene or hydrogen sulfide, which are prone to decomposition or polymerization at high temperatures.
8. Rolling Piston Compressors
Working Principle
Rolling piston compressors operate by rotating an eccentric piston inside a cylindrical chamber. The piston compresses gas by reducing the volume of the chamber as it rotates, pushing gas toward the exhaust.
Advantages
Compact and lightweight, making them ideal for small applications.
Fewer parts and simple design result in high reliability.
Efficient at compressing gases in small to medium volumes.
Disadvantages
Limited to low-pressure applications.
Higher friction and leakage due to the movement between the piston and chamber.
Applications
Common in residential air conditioners and refrigerators, rolling piston compressors are ideal for compact, efficient, and low-cost solutions.
Whether it’s for large-scale air conditioning or small refrigeration units, selecting the right compressor ensures optimal performance, energy efficiency, and longevity of the system. Lamnow is a compressor motor lamination China manufacturer, our stator and rotor stacks are suitable for 8 types of compressors. Please contact us if you need to.
