How a Scroll Compressor Works
Unlike reciprocating technology with many moving parts, the Copeland scroll compressor has one scroll or spiral orbiting in path defined by a matching fixed scroll. The fixed scroll is attached to the compressor body. The orbiting scroll is couple to the crankshaft in orbit rather then rotated.
The orbiting motion creates a series of gas pockets traveling between the two scrolls. On the outer portion of the scroll the pocket draw in gas, then move it to center of the scroll where it’s discharged. As the gas moves in the increasing smaller inner pocket, the temperature and pressure increase to the desired discharged pressure.
Copeland's Compliant Scroll technology is based on the concept of compliance. Compliance refers to the method in which the two scroll members interact to simultaneously achieve high efficiency and durability. Copeland's unique and patented approach -- achieving both radial and axial compliance -- provides the following important advantages:
- Continuous flank contact, maintained by centrifugal force, minimizes gas leakage and maximizes efficiency.
- Radial compliance allows the scroll members to separate in the presence of liquid refrigerant or debris, thereby substantially improving durability and reliability.
- Axial compliance allows the scroll to remain in continuous contact in all normal operating conditions, ensuring minimal leakage without the use of tip seals.
- Both radial and axial compliance allow the scroll members to actually "wear in" rather than wear out.
Scroll Compressor Efficiency
The simple straightforward design of Copeland Scroll compressors makes them inherently more efficient. That's why leading manufacturers so often specify Copeland Scroll compressors for systems designed to meet the highest efficiency levels. Since there are no pistons to compress gas, scroll compressors achieve 100% volumetric efficiency, which provides reduced energy costs in many applications. Re-expansion losses, which typically occur with each piston stroke in reciprocating models, are eliminated. Similarly, losses at valves are eliminated, because suction valves do not exist.
During operation, centrifugal force maintains nearly continuous compression and constant, leak-free contact. Separation of suction and discharge gases reduces heat transfer loss.
Copeland Scroll compressors' simple design means they operate at lower sound and vibration levels than reciprocating compressors. In fact, tests have shown that scroll compressors are up to three times quieter than reciprocating models. One reason for the lower sound levels is the Copeland Scroll compressors require no suction valves to achieve efficient compression. The smooth operation results in quieter operation with less vibration.
That not only gives you greater flexibility when it comes to system design and placement, it also means you can satisfy the requirements of your most demanding customers for quiet operation. Maybe that's one reason Popular Science called Copeland Scroll compressors "the first significant new development in the HVAC industry in years."