The mechanical properties of many materials have been enhanced via cryogenic treatment, which is a cold temperature process performed after traditional heat treatment. In this research the effect of cryogenic treatment on GRCop-84 was examined. Cryogenically and non-cryogenically treated samples were tested identically to determine whether cryogenic treatment has a significant affect on the thermal conductivity of GRCop-84. Optical and electron microscopy were used to characterize the material properties. Cryogenic treatment includes a temper that appears to be responsible for the enhancements observed in GRCop-84.
Cryogenic treatment is a cold temperature process performed after traditional heat treatment, not a substitute for proper heat treatment. Cryogenic treatment has been shown to enhance mechanical properties in many materials. The effect of cryogenic treatment on the thermal conductivity of a copper alloy developed by NASA (GRCop-84) was tested. Potential applications of GRCop-84 include regeneratively cooled rocket engine liners.
Source:http://web.ebscohost.com/ehost/pdf?vid=1&hid=104&sid=8f79dbbe-f760-4574-90f7-3e443e7cbffc%40sessionmgr104
Tuesday, September 22, 2009
Cryogenic treatment of production components in High-wear rate wells
"Deep Cryogenic Tempering (DCT) is a specialized processwhereby the molecular structure of a material is “re-trained” through cooling to –300º F and then heating to +175-1100º F. Three Shannon Formation wells were selected (TD about 500 ft) based on their proclivity for high component wear rates.
Phase 1 of the test involved operation for a nominal 120 calendar day period with standard, non-treated components. In Phase 2, treated components were installed andoperated for another nominal 120 calendar day period. Different cryogenic treatmentprofiles were used for components in each well. Rod pumps (two treated and oneuntreated) were not changed between test phases. One well was operated in pumped-offcondition, resulting in abnormal wear and disqualification from the test. Testing showsthat cryogenic treatment reduced wear of rods, couplers, and pump barrels. Testing ofproduction tubing produced mixed results."
Source: http://www.osti.gov/bridge/servlets/purl/794381-1aya1J/native/794381.pdf
Phase 1 of the test involved operation for a nominal 120 calendar day period with standard, non-treated components. In Phase 2, treated components were installed andoperated for another nominal 120 calendar day period. Different cryogenic treatmentprofiles were used for components in each well. Rod pumps (two treated and oneuntreated) were not changed between test phases. One well was operated in pumped-offcondition, resulting in abnormal wear and disqualification from the test. Testing showsthat cryogenic treatment reduced wear of rods, couplers, and pump barrels. Testing ofproduction tubing produced mixed results."
Source: http://www.osti.gov/bridge/servlets/purl/794381-1aya1J/native/794381.pdf
Wednesday, September 9, 2009
Deep-Cryogenic Treatment of Steel
The deep cryogenic tempering process for gears is an inexpensive, one time, permanent treatment, affecting the entire part, not just the surface. Gears may be new or used, sharp or dull, and re-shaping will not destroy the treatment.
The process of deep cryogenic or freeze tempering is really quite simple. “A freeze tempering process means that the material to be treated is not exposed to any liquid nitrogen, which eliminates the risk of thermal shock. The material is frozen through a thermo dynamic refrigeration cycle. The material is cooled slowly, held for a prolonged period of time 48-60 hours, and allowed to return to room temperature slowly.”
Source: http://coldfire.com.au/uploads/Deep_Cryo_Article-Ferland.pdf
The process of deep cryogenic or freeze tempering is really quite simple. “A freeze tempering process means that the material to be treated is not exposed to any liquid nitrogen, which eliminates the risk of thermal shock. The material is frozen through a thermo dynamic refrigeration cycle. The material is cooled slowly, held for a prolonged period of time 48-60 hours, and allowed to return to room temperature slowly.”
Source: http://coldfire.com.au/uploads/Deep_Cryo_Article-Ferland.pdf
Frozen Gears
Durability is the most important criterion used to define the quality of a gear. The freezing of metals has been acknowledged for almost thirty years as an effective method for increasing durability or wear life, and decreasing residual stress in tools steels. The recent field of deep cryogenic (below-300°F) has brought high super conductors, the superconducting super collider, cryo-biology, and magneto hydrodynamic drive systems. It has also brought many additional durability benefits to metals.
Monday, September 7, 2009
Cutting Tools Engineering
Although its effects on metal composition are subtle, deep cryogenic tempering can yield dramaticimprovements in tool performance.In the search for cutting tool engineering that can increase productivity, prolong cutting life, and decrease costs, gains of 15% to 20% are considered significant. One recently developed tool treatment is showing far greater promise, in some cases improving tool life by 200% to 400%.
The method, called deep cryogenic tempering, subjects tools placed in a specially constructed tank to temperatures below -300 ° F for a number of hours using liquid nitrogen as the refrigerant. The process supplements standard heat/quench tempering, completing metallurgical changes that heat treatingbegins.
Monday, August 31, 2009
Controlled Dry Cryogenic Process
What is a controlled dry cryogenic process?
Cryogenics, a product of aerospace research, refers to temperatures below (-280°F). A dry process means that material to be treated is not exposed to any cryogenic liquids, which eliminates the risk of thermal shock. The material is frozen through a thermo-dynamic refrigeration cycle. Controlled simply states that the entire process is performed according to a precise, prescribed time table. The material is cooled slowly, held for prolonged period of time, 20-60 hours, and allowed to return to room temperature slowly.
The treated material maintains its original size and shape throughout the cryogenic process. Although a material is stronger at lower temperatures, following treatment, they show no change in yield of tensile strength. The treated material does become less brittle but without losing hardness. What does change most significantly and considerably is an increase in the material's toughness, stability and wear resistivity.
In contrast to various other surface treatments, the dry cryogenic treatment is a one time only process and affects the material through and through. Re-sharpening or redressing of worn tools does not destroy the effects of the treatment. Tools may be new or used, sharp or dull.
Source: http://www.300below.com/press/magazine-articles/the-promise-of-cryo.html
Cryogenics, a product of aerospace research, refers to temperatures below (-280°F). A dry process means that material to be treated is not exposed to any cryogenic liquids, which eliminates the risk of thermal shock. The material is frozen through a thermo-dynamic refrigeration cycle. Controlled simply states that the entire process is performed according to a precise, prescribed time table. The material is cooled slowly, held for prolonged period of time, 20-60 hours, and allowed to return to room temperature slowly.
The treated material maintains its original size and shape throughout the cryogenic process. Although a material is stronger at lower temperatures, following treatment, they show no change in yield of tensile strength. The treated material does become less brittle but without losing hardness. What does change most significantly and considerably is an increase in the material's toughness, stability and wear resistivity.
In contrast to various other surface treatments, the dry cryogenic treatment is a one time only process and affects the material through and through. Re-sharpening or redressing of worn tools does not destroy the effects of the treatment. Tools may be new or used, sharp or dull.
Source: http://www.300below.com/press/magazine-articles/the-promise-of-cryo.html
Advancement of Cryogenic Science
All Aluminum and aluminum alloy castings have built-in stress due to the shrinkage of the molten metal after it cools in the molds. Some of these stresses can be reduced and in some areas eliminate by good casting design, by the foundry properly incorporating stress risers.
Castings that have to be machined for closer tolerances, flatness and better surface finishes will, in most cases, distort on these surfaces, which in turn affects the tolerances and flatness of the critical areas. This distortion starts when the outer layer is removed by machining.... this outer layer locks in the stresses and when removed, the machined surfaces will de distorted.
What can be done to relive these stresses before machining?
Through the advancement of cryogenic science, it has been discovered and proven that when these castings are treated in a cryogenic chamber at temperatures of 88°F Kelvin (-300°F) at a controlled time/temperature cycle, all internal stresses are relived. These components will now retain a flatness/parallelism here-to-fore not possible.
They will maintain a dimensional stability in their use function far above the non-treated part. This is due to the re-alignment of molecular structure that has been distorted during the casting or heat treating process. When these cryogenically treated castings are machined, there us no distortion on the machined surfaces… if there is a distortion, it is caused by improper machining, dull cutting tools, speeds and feeds being too slow and /or not enough material removed at the first cut.
Source: http://www.300below.com/press/magazine-articles/controlled-dry-cryogenic-process.html
Castings that have to be machined for closer tolerances, flatness and better surface finishes will, in most cases, distort on these surfaces, which in turn affects the tolerances and flatness of the critical areas. This distortion starts when the outer layer is removed by machining.... this outer layer locks in the stresses and when removed, the machined surfaces will de distorted.
What can be done to relive these stresses before machining?
Through the advancement of cryogenic science, it has been discovered and proven that when these castings are treated in a cryogenic chamber at temperatures of 88°F Kelvin (-300°F) at a controlled time/temperature cycle, all internal stresses are relived. These components will now retain a flatness/parallelism here-to-fore not possible.
They will maintain a dimensional stability in their use function far above the non-treated part. This is due to the re-alignment of molecular structure that has been distorted during the casting or heat treating process. When these cryogenically treated castings are machined, there us no distortion on the machined surfaces… if there is a distortion, it is caused by improper machining, dull cutting tools, speeds and feeds being too slow and /or not enough material removed at the first cut.
Source: http://www.300below.com/press/magazine-articles/controlled-dry-cryogenic-process.html
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