Torad Spool Compressor
Spool compressors are said to be capable of variable-speed operation and will be available in open, semi-hermetic, and hermetic configurations for its 5- to 300-hp designs.

Move over compression ratio, ring valve, and reciprocating compressors. There are two new terms to add to your refrigeration terminology: ‘bi-volt’ and ‘spool.’ The words relate to some of the newest developments in compressor applications.


Embraco, a manufacturer of hermetic compressors, has announced an electronic control which adjusts the voltage of an entire system.

“Traditionally, for equipment like refrigerators and freezers, voltage transformers are needed,” the company said. This “significantly increases the cost of the system and the space occupied by it in the final product.”

The technological difficulties to deal with this were eliminated, the company said, with a compressor that has an electronic circuit board which recognizes the input voltage being applied to the product, automatically adjusting the voltage supplied to the system loads (compressor, fan, defrost resistance, and lightbulb).

“Our history of innovation associated with the technological expertise also in electronics made the feasibility of a simple, efficient and unique solution possible in the refrigeration market,” said Embraco Vice President of Business and Marketing Roberto H. Campos.

According to the executive, initially the bi-volt compressors are compatible with domestic refrigerators and freezers. But Embraco will also eventually offer bi-volt compressors for light commercial applications, such as refrigerator counters and refrigerated display cases.

With an installed capacity of 2.5 million units for the new product, the first bi-volt components for refrigerators reached the market in December in Brazil, a country where there are two standard voltages: 127 V and 220 V.

“The new development, which generated five patents, benefits manufacturers, consumers, and especially retailers, who will be able to better calculate their inventory to meet demands of peak consumption and will have an easier time planning distribution logistics and carrying out regional promotions,” the company said.


At the Air-Conditioning, Heating, and Refrigerating Expo held this winter, Torad LLC unveiled the Spool compressor which “offers a simple design, high displacement density, along with a scalable design,” the company said. The compressor is capable of variable-speed operation and will be available in open, semi-hermetic, and hermetic configurations for its 5- to 300-hp designs.

Torad president, Joe Orosz, explained that since 2007 the research and development team at Torad has worked to produce several working prototypes in finalizing the design of the Spool compressor. “It is important to us at Torad to listen to the needs of the HVAC industry and provide a product that will offer incredible advantages to the complete design,” he said. “It is perfect timing to introduce this viable engineered alternative, especially one that can dramatically cut compressor cost of over 25 percent, decrease the physical size/weight, and doing this without sacrificing any of the performance areas.”

Torad’s design includes four main components: rotor, main housing, gate, and bearing housings. The components make up a single rotating spool assembly for the compressor.

Greg Kemp, CEO and inventor of the technology, said, “Spool technology combines the positive sealing of a piston compressor with the reliability of a screw or scroll compressor. We have made a significant breakthrough in compressor simplicity, capacity density, and manufacturing costs which will allow us to position the Spool compressor to dramatically change the air conditioning and refrigeration compressor marketplace.”

The Spool compressor is said to have high efficiency levels over a wide range of sizes. Its features include tolerance of liquid floodback and no axial load assists in bearing longevity.

Publication date: 03/26/2012