Cryogenic processor
Encyclopedia
A Cryogenic processor is unit designed to reach ultra-low temperatures (usually around -300°F / -150°C) at a slow rate in order to prevent thermal shock
to the components being treated. The first commercial unit was developed by Ed Busch in the late 1960s. The development of programmable microprocessor controls allowed the machines to follow temperature profiles that greatly increased the effectiveness of the process. Some manufacturers make cryoprocessors with home computers to define the temperature profile. The reliability of these computers in an industrial environment is greatly in doubt.
Before programmable controls were added to control cryogenic processors, the "treatment" process of an object was previously done manually by immersing the object in liquid nitrogen
. This normally caused thermal shock to occur within an object, resulting in cracks to the structure. Modern cryogenic processors measure changes in temperature and adjust the input of liquid nitrogen accordingly to ensure that only small fractional changes in temperature occur over a long period of time. Their temperature measurement
s and adjustments are condensed into "profiles" that are used to repeat the process in a certain way when treating for similarly grouped objects.
The general processing cycle for modern cryogenic processors occurs within a three day time window, with 24 hours to reach the optimal bottom temperature for a product, 24 hours to hold at the bottom temperature, and 24 hours to return to room temperature. Depending on the product, some items will be heated in an oven to even higher temperatures. Some processors are capable of providing both the negative and positive extreme temperatures, separate units (a cryogenic processor and a dedicated oven) can sometimes produce better results depending upon the application.
The optimal bottom temperatures for objects, as well as the hold times involved, are determined utilizing a number of different research methods and backed by experience and analysis to determine what works the best for a given product. As new metals are used in different combinations for newer products on the market, processing profiles change to accommodate the changes in structure. Also, profiles will sometimes undergo change from the results of a case study brought to attention by a large manufacturer or consumer of cryogenic services. Generally when a manufacturer sells a cryogenic processor they include the profiles for only that year of manufacture, or, more typically, profiles from when the processor model was first engineered, which sometimes will date back several years. Many businesses will include outdated profiles simply because they do not have adequate funding to perform the necessary ongoing research.
For people looking to find thermal profiles for cryogenics, a number of companies maintain thermal profiles of various products that are updated for accuracy at least a few times a year with their ongoing research, including data from independent trials and studies. However, obtaining these profiles is sometimes difficult if they are not used for educational purposes (mainly institutional research), as they typically only provide the updated profiles to their longtime "service center" partners around the world.
Overall, cryogenic processors are radically changing the way that cryogenics used to be done. Many years ago, cryogenics was simply theoretical, with spotty results when there were improvements. Now, cryogenic processors are ensuring the accurate and consistent results for all products that are treated these days. As the technology sector improves, cryogenic processors will only get better as they benefit from new computer systems. Ongoing research in the future will also improve their temperature treatment profiles.
Thermal shock
Thermal shock is the name given to cracking as a result of rapid temperature change. Glass and ceramic objects are particularly vulnerable to this form of failure, due to their low toughness, low thermal conductivity, and high thermal expansion coefficients...
to the components being treated. The first commercial unit was developed by Ed Busch in the late 1960s. The development of programmable microprocessor controls allowed the machines to follow temperature profiles that greatly increased the effectiveness of the process. Some manufacturers make cryoprocessors with home computers to define the temperature profile. The reliability of these computers in an industrial environment is greatly in doubt.
Before programmable controls were added to control cryogenic processors, the "treatment" process of an object was previously done manually by immersing the object in liquid nitrogen
Liquid nitrogen
Liquid nitrogen is nitrogen in a liquid state at a very low temperature. It is produced industrially by fractional distillation of liquid air. Liquid nitrogen is a colourless clear liquid with density of 0.807 g/mL at its boiling point and a dielectric constant of 1.4...
. This normally caused thermal shock to occur within an object, resulting in cracks to the structure. Modern cryogenic processors measure changes in temperature and adjust the input of liquid nitrogen accordingly to ensure that only small fractional changes in temperature occur over a long period of time. Their temperature measurement
Temperature measurement
Attempts of standardized temperature measurement have been reported as early as 170 AD by Claudius Galenus. The modern scientific field has its origins in the works by Florentine scientists in the 17th century. Early devices to measure temperature were called thermoscopes. The first sealed...
s and adjustments are condensed into "profiles" that are used to repeat the process in a certain way when treating for similarly grouped objects.
The general processing cycle for modern cryogenic processors occurs within a three day time window, with 24 hours to reach the optimal bottom temperature for a product, 24 hours to hold at the bottom temperature, and 24 hours to return to room temperature. Depending on the product, some items will be heated in an oven to even higher temperatures. Some processors are capable of providing both the negative and positive extreme temperatures, separate units (a cryogenic processor and a dedicated oven) can sometimes produce better results depending upon the application.
The optimal bottom temperatures for objects, as well as the hold times involved, are determined utilizing a number of different research methods and backed by experience and analysis to determine what works the best for a given product. As new metals are used in different combinations for newer products on the market, processing profiles change to accommodate the changes in structure. Also, profiles will sometimes undergo change from the results of a case study brought to attention by a large manufacturer or consumer of cryogenic services. Generally when a manufacturer sells a cryogenic processor they include the profiles for only that year of manufacture, or, more typically, profiles from when the processor model was first engineered, which sometimes will date back several years. Many businesses will include outdated profiles simply because they do not have adequate funding to perform the necessary ongoing research.
For people looking to find thermal profiles for cryogenics, a number of companies maintain thermal profiles of various products that are updated for accuracy at least a few times a year with their ongoing research, including data from independent trials and studies. However, obtaining these profiles is sometimes difficult if they are not used for educational purposes (mainly institutional research), as they typically only provide the updated profiles to their longtime "service center" partners around the world.
Overall, cryogenic processors are radically changing the way that cryogenics used to be done. Many years ago, cryogenics was simply theoretical, with spotty results when there were improvements. Now, cryogenic processors are ensuring the accurate and consistent results for all products that are treated these days. As the technology sector improves, cryogenic processors will only get better as they benefit from new computer systems. Ongoing research in the future will also improve their temperature treatment profiles.
See also
- cryogenicsCryogenicsIn physics, cryogenics is the study of the production of very low temperature and the behavior of materials at those temperatures. A person who studies elements under extremely cold temperature is called a cryogenicist. Rather than the relative temperature scales of Celsius and Fahrenheit,...
- cryogenic processing
- cryogenic tempering
- 300 Below
- absolute zeroAbsolute zeroAbsolute zero is the theoretical temperature at which entropy reaches its minimum value. The laws of thermodynamics state that absolute zero cannot be reached using only thermodynamic means....
- coldest temperature achieved on earthColdest temperature achieved on EarthThe lowest temperature ever recorded at the surface of the Earth was at the Russian Vostok Station in Antarctica July 21, 1983. Lower temperatures have been achieved in the laboratory, including a record low temperature of 100 pK, or 1.0 × 10-10 K in 1999.- Early cooling :In...
- refrigerationRefrigerationRefrigeration is a process in which work is done to move heat from one location to another. This work is traditionally done by mechanical work, but can also be done by magnetism, laser or other means...
- superfluidity
- superconductivitySuperconductivitySuperconductivity is a phenomenon of exactly zero electrical resistance occurring in certain materials below a characteristic temperature. It was discovered by Heike Kamerlingh Onnes on April 8, 1911 in Leiden. Like ferromagnetism and atomic spectral lines, superconductivity is a quantum...
- quantum hydrodynamicsQuantum hydrodynamicsQuantum hydrodynamics is most generally the study of hydrodynamic systems which demonstrate behavior implicit in quantum subsystems . They arise in semiclassical mechanics in the study of semiconductor devices, in which case being derived from the Wigner-Boltzmann equation...
- cryocoolers