US3878112A - Lubricant-refrigerant system for centrifugal refrigeration compressors - Google Patents
Lubricant-refrigerant system for centrifugal refrigeration compressors Download PDFInfo
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- US3878112A US3878112A US472772A US47277274A US3878112A US 3878112 A US3878112 A US 3878112A US 472772 A US472772 A US 472772A US 47277274 A US47277274 A US 47277274A US 3878112 A US3878112 A US 3878112A
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- lubricant
- fluorocarbon
- diricinoleate
- refrigerant
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04D—NON-POSITIVE-DISPLACEMENT PUMPS
- F04D29/00—Details, component parts, or accessories
- F04D29/06—Lubrication
- F04D29/063—Lubrication specially adapted for elastic fluid pumps
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M171/00—Lubricating compositions characterised by purely physical criteria, e.g. containing as base-material, thickener or additive, ingredients which are characterised exclusively by their numerically specified physical properties, i.e. containing ingredients which are physically well-defined but for which the chemical nature is either unspecified or only very vaguely indicated
- C10M171/008—Lubricant compositions compatible with refrigerants
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2203/00—Organic non-macromolecular hydrocarbon compounds and hydrocarbon fractions as ingredients in lubricant compositions
- C10M2203/003—Organic non-macromolecular hydrocarbon compounds and hydrocarbon fractions as ingredients in lubricant compositions used as base material
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2207/00—Organic non-macromolecular hydrocarbon compounds containing hydrogen, carbon and oxygen as ingredients in lubricant compositions
- C10M2207/28—Esters
- C10M2207/283—Esters of polyhydroxy compounds
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2207/00—Organic non-macromolecular hydrocarbon compounds containing hydrogen, carbon and oxygen as ingredients in lubricant compositions
- C10M2207/28—Esters
- C10M2207/283—Esters of polyhydroxy compounds
- C10M2207/2835—Esters of polyhydroxy compounds used as base material
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2211/00—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
- C10M2211/02—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only
- C10M2211/0206—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only used as base material
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2211/00—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
- C10M2211/02—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only
- C10M2211/022—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only aliphatic
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2211/00—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
- C10M2211/02—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only
- C10M2211/022—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only aliphatic
- C10M2211/0225—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only aliphatic used as base material
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2211/00—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
- C10M2211/02—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only
- C10M2211/024—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only aromatic
- C10M2211/0245—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only aromatic used as base material
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2211/00—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
- C10M2211/04—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen, halogen, and oxygen
- C10M2211/042—Alcohols; Ethers; Aldehydes; Ketones
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2211/00—Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
- C10M2211/06—Perfluorinated compounds
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10M—LUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
- C10M2223/00—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions
- C10M2223/02—Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions having no phosphorus-to-carbon bonds
- C10M2223/04—Phosphate esters
- C10M2223/041—Triaryl phosphates
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/30—Refrigerators lubricants or compressors lubricants
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/32—Wires, ropes or cables lubricants
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/34—Lubricating-sealants
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/36—Release agents or mold release agents
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/38—Conveyors or chain belts
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/40—Generators or electric motors in oil or gas winning field
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/42—Flashing oils or marking oils
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/44—Super vacuum or supercritical use
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- C—CHEMISTRY; METALLURGY
- C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
- C10N—INDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
- C10N2040/00—Specified use or application for which the lubricating composition is intended
- C10N2040/50—Medical uses
Definitions
- ABSTRACT A lubricant-refrigerant system for centrifugal refrigeration compressors comprising a synthetic lubricant consisting essentially of a diricinoleate of at least one glycol selected from the group consisting of two to five carbon atom glycols, and a fluorocarbon refrigerant.
- the glycol diricinoleate has a very low solubility for the fluorocarbon refrigerant, has viscosity and pour point characteristics, as well as wear and lubricity properties suitable for adequate lubrication of the bearings, gears, and other components of a centrifugal compressor under all reasonable conditions of use, it is thermally and chemically stable in the presence of the fluorocarbon and the metals usually used in compressors over all reasonably expected service conditions, and enables rapid start-up of the centriifugal compressor.
- Piston type units are not only relatively large for a given horsepower but they are noisy and vibrate. Centrifugal compressors driven by, for example, 50 to 600 horsepower electric motors have been found to be much more compact so that they occupy only a fraction of the space required for a piston type unit of the same horsepower. Furthermore considering the horsepower, the high speeds of up to 36,000 rpm of the centrifugal compressor, and large volumes of refrigerant handled per unit time, the compressor units are extremely quiet and are characterized by very little vibration.
- centrifugal compressors have often taken several hours. Under all conditions, a separate oil pump unit is first set in operation to deliver a flow of lubricating oil to the bearings, gears and oil-operated control mechanism, and only after an adequate flow of lubricant has been established, is the centrifugal compressor put into operation. Initial high thrust loads are encountered in the impeller bearings requiring good lubricant films to be present at all times when in operation.
- one involved procedure to mitigate this lubrication problem in centrifugal compressors is to provide a heater in or about the oil sump so that the oil will be heated up to and maintained at, for instance, F to minimize the amount of the fluorocarbon refrigerant, such as Rl2, in solution in the oil, which at this temperature comprises some 1 1%.
- the oil sump is initially heated for several hours (using for instance 5 KW heaters) in order to drive out as much fluorocarbon from the progressively heated oil as is reasonably possible before actual operation of the oil pump of the compressor.
- the oil pump is then energized to pump the hot oil with low fluorocarbon content through the oil lines and into the bearings. In these latter areas, the oil is cooled by contact with the cold metal and redissolves more fluorocarbon and the cooled oil with a large quantity of dissolved fluorocarbon flows through the oil lines, bearings and gear case and reenters the sump where it is reheated.
- Esters of castor oil and esters of ricinoleic acid have been prepared heretofore.
- some of these castor oil esters and ricinoleic acid esters are suitable for metal cutting or drawings lubricants.
- US. Pat. Nos. 3,634,245 and 3,720,695 discloses castor oil trans-esterified with polymeric alkylene oxide glycols which esters are water soluble compounds suitable for use as die lubricants.
- the indicated application for these esters is primarily for lubricating the surfaces of metal forming dies, such as are used for cold or hot reducing steel, hot metal cutting and grinding operations, as well as wire drawings.
- German patent 1,132,123 is directed to the preparation of lubricants by reacting ricinoleic acid with polyethylene glycols.
- British patents 573,202; 591,421; 590,386; and 657,750 are directed generally to the manufacture of ricinoleic esters as well as other esters for use as lubricants in automobile engines and the like. None of this art listed teaches the employment of any of these esters in refrigeration machinery where it would be in contact with a fluorocarbon.
- centrifugal refrigeration compressors employing a fluorocarbon refrigerant are lubricated with certain synthetic diricinoleic acid esters of selected glycols, which avoid these prior art problems, so that the centrifugal compressors can be safely and satisfactorily started at any time with no appreciable delay.
- the synthetic esters employed in the system of this invention are excellent lubricants, having a suitable viscosity of from about 200 to 600 SUS at 100F and from about 40 to 90 SUS at 212F, and a low pour-point of from about 30 to 40F, satisfactorily meeting the requirements for the centrifugal compressors, they also have excellent anti-wear properties enabling their eminently successful use for lubricating gears and the like in this application, and have sufficiently good thermal stability properties in the presence of the fluorocarbons and metals so that no chemical failure will occur in reasonably expected service for an acceptable lifetime of many years. These esters also have the prime characteristics of dissolving only small amounts of fluorocarbon refrigerants such as dichlorodifluoromethane (R-12), so that excessive foaming and other previously encountered difficulties are avoided.
- fluorocarbon refrigerants such as dichlorodifluoromethane (R-12)
- the synthetic esters exhibiting this unique combination of properties are the diricinoleic esters of 2 to 5 carbon atom hydrocarbon glycols, and particularly, ethylene glycol, propylene glycol 1,4-butanediol, and 1,5-pentane-diol. Mixture of two or more of the glycols can be employed. Small quantities of lubricant additives may be incorporated in these esters examples being extreme pressure lubricating additives such as dodecylmonochlorodiphenyl oxide and other anti-wear agents, such as tricresyl phosphate.
- FIG. 1 is a vertical cross-section through a portion of an exemplary centrifugal refrigeration compressor
- FIG. 2 is a schematic diagram with portions in crosssection of a centrifugal refrigeration compressor.
- FIG. 1 of the drawings there is shown a vertical cross section through a portion of a typical centrifugal refrigeration compressor 10.
- the refrigeration compressor comprises a motor 12, for example from 50 to 600 horsepower, within a casing 14.
- the casing 14 includes bearings in which is mounted a motor drive shaft 18 extending through a bearing 16 into a gear compartment 20, with the right-hand end of the shaft being supported in a bearing 21.
- the portion of the shaft 18 in gear compartment 20 is provided with a large driven helical spur gear 22 driving smaller gear 24 affixed to a centrifugal impeller shaft 28.
- the ratio of the diameters of gears 24 and 22 is of the order to 10:1 so that when motor 12 is operating at 1800 rpm the compressor shaft will be rotating at a speed of 18,000 rpm, while a 3,600 rpm motor may drive the compressor at from 32,000 to 36,000 rpm.
- the ends of centrifugal impeller shaft 28 are mounted in bearings 32 and 34. Lubricant is supplied to the bearings 16, 32, 34 through channels 36, 38 and 40 from a main lubricant manifold 42. Bearing 21 is lubricated by a lubricant manifold 23. Because of the high speeds and high power being transmitted to the impeller it is mandatory that a large volume of lubricant be supplied to the bearings at all times during the operation of the compressor.
- centrifugal compressor impeller 44 Upon the extreme right-hand end of the shaft 28 is mounted a centrifugal compressor impeller 44 having an inlet end 46 adjacent the right-hand end of the shaft hub and an exit portion 48 at which hot compressed refrigerant gases are expelled under pressure into a refrigerant gas mainifold 50 from where they flow to a suitable condenser (not shown).
- Refrigerant gas enters through a relatively large gas inlet conduit 52 at the extreme right-hand end of the compressor, as shown in FIG. 1. Admission of the fluorocarbon gas in conduit 52 to the inlet end 46 of the compressor is controlled by a series of circumferentially positioned inlet vanes 54 pivotally mounted in the conduit 52 in front of the inlet end of the centrifugal impeller.
- the vanes 54 are rotated to a desired gas flow control position by a piston member 56 having portions affixed to eccentrically placed pins on the vanes 54, which piston member moves in response to admission of lubricant under pressure to one or the other end thereof in response to amounts of refrigerant needed as determined by a vane control sensor mechanism (not shown) to move the vanes 54 to any position between fully open and a substantially closed position. Consequently flow of fluorocarbon refrigerant gas to the centrifugal impeller is controlled by this vane and piston mechanism.
- FIG. 2 of the drawings there is illustrated schematically the distribution of lubricant to the centrifugal refrigeration compressor of FIG. 1.
- An enclosed oil sump and pump unit 60 encloses a motor 62 operating a pump 64 disposed within the lower portion thereof where it is immersed within a reservoir of lubricant 66 which will ordinarily be present at some level therein at all times.
- Lubricant escaping from the bearings, gears casing, and the vane control system enters by way of a conduit 68 into the sump 60.
- the oil returning to the sump conduit 68 has been exposed to and has dissolved therein fluorocarbon refrigerant.
- the amount of dissolved fluorocarbon refrigerant for example, R-l2 is related to the gas pressure and the temperature of the oil.
- the previously referred to article in the American Society of Mechanical Engineers publications contains a FIG. 3 which correlates the pressure and temperature of the oil to the solubility of R-l2 refrigerant in petroleum base oils.
- the amount of R-l2 fluorocarbon dissolved therein will be approximately 12%.
- the percentage of R 12 dissolved therein will be of the order of 50%.
- oil under pressure is conveyed through a pipe 70, passing first through a filter 72 to remove any solid particles therefrom and then through an oil cooler 74 to reduce the temperature of the oil.
- the cooled oil then is conveyed by a pipe 76 to manifold 23 and thence to the right-hand end bearing 21, supporting motor shaft 18, and also through a pipe 78 to the oil manifold 42 from where an abundant flow of oil is directed to the bearings 16, 32 and 34.
- oil is conveyed through conduit 80 to a vane control mechanism 81 operated by a suitable sensor (not shown), which feeds requisite amounts of oil through lines 82 and 84 to the vane control piston 56.
- the solubility of an R-l2 fluorocarbon refrigerant in good grade petroleum base lubricants employed in centrifugal refrigeration compressors is high.
- the solubility of fluorocarbons is as follows: At 26C (78F) the solubility of R-l2 gas (96 psia) in both 5G5 and 4GS lubricants is about by weight or 43% by liquid volume. R-l2 liquid in contact with these two lubricants is infinitely soluble. Furthermore, at lower temperatures, the solubility of R-l 2 gas in these lubricants is even greater.
- the Ap is indicative of the amount of R-l2 gas dissolved in the respective fluid.
- Table II sets forth solubility properties of R12 computed from both liquid and gas absorption weight measurements.
- Table Suniso 5G8 50 55 III sets forth these viscosity characteristics of the sev- Suniso 4G5 45 5() eral lubricants of the present invention and others for Tetrflcthtfleneslywl 3 y Castor Oil 44 (Still on Test) compdnson' Ethylene Glycol TABLE III Diricinoleate 4043 Propylene Glycol Diricinoleate 36 Viscosity (SUS) Pour Propylene Glycol Fluid IO0F 2I()F Point "F Monoricinoleate 37 37 I3 45 Suniso SGS 500 52 -35 Suniso 4G8 285 46 -40 Castor on 1555 103 -10 Experience has shown that most of the chemical retf s F Glywl activity reactions involved follow the 10C rule, namely Dlrlcinoleate 600 80 40 o pmpflene G
- the ethylene and propylene diricinoleate are shown to have the same order to chemical stability toward R-12 at C, as the currently used naphthenic base refrigerator oils, Suniso 4G8 and SGS.
- propylene glycol monoricinoleate is inferior to the other fluids tested, and is not considered therefore, like a satisfactory candidate.
- test blocks having V grooves are disposed on either side of a rotatable pin driven by a motor at 290 rpm and a pressure is applied to the V blocks up to a maximum of 4500 lbs.
- the V blocks and rotating shaft are immersed in the lubricant being tested which is heated to a predetermined standard temperature and the motor operated over a period of several hours.
- the wear of the pins in this instance, when operated at 250 lb. gauge pressure is expressed in standard units per hour. The lower the wear units per hour, the better the lubricant.
- the pin and blocks are prepared from standard steels which have been found to be readily correlated with many bearing steels.
- a recently devised test known as the Ryder 4-square gear test is frequently used to evaluate the load carrying capacity of lubricants involved in the lubrication of gears.
- This test is outlined in Federal Standards Number 791, Method 650.8, as required in 'ASTM D-1947 Specification. Briefly, in this test, an oil is evaluated in a standard 4-square gear machine at increasing loads under controlled conditions. The amount of tooth face scuffing occurring at each load increment is measured. The percentage of tooth face scuffing is plotted against the load to determine the load carrying capacity of the oil under these tests.
- the test gears used in this test are special spur gears made of case hardened and ground SAE.9310 steel. This steel is the same composition as that which is used commercially for producing the gearing in the compressor of FIG. 1. Test data comparing Suniso 4G8 and ethylene glycol diricinoleate using the Ryder test results are set forth in the Table VI.
- the diricinoleic acid-glycol esters may be prepared in accordance with the prior art esterification practices. It is desirable to remove any unreacted glycols and mono-ricinoleates therefrom by appropriate vacuum stripping. Esterification catalysts also should be removed in order to avoid any undesired reactions when the esters are used as disclosed herein. Minor proportions of other lubricants may be added to the glycol diricinoleate esters of this invention. Low viscosity ricinoleates such as methyl ricinoleate may be added in amounts of, for example, 2 to 10%.
- the first unit extensively tested was a 500 horsepower (480 Ton) unit which required about 12 gallons of a lubricant-either Suniso 4GS petroleum base oil or the ethyleneglycol-diricinoleate ester of this invention.
- the unit employed several hundred pounds of R-12 refrigerant.
- With the petroleum base oil after the unit had stood for 4 to 6 hours at to F, with a sump refrigerant pressure due to the R-12 gas of from 60 to 70 psi, considerable difficulty was experienced in attempting a start-up. Foaming was so extensive after the oil pump in the sump was started that an automatic trip operating upon excessive oil pressure drop in the oil line, made it impossible to start the centrifugal compressor motor and have it keep running.
- the temperature of the diricinoleate ester in the sump was 80F.
- the oil pump was started and the viscosity of the cold diricinoleate ester lubricant was relatively high so that the oil pump was pulling a high current of from 5.5 to 5.9 amperes in order to cope with the thick lubricant: this is a roughly 40% overload since under normal load conditions the oil pump motor pulls from about 4.4 to 4.6 amperes.
- the Table VII sets forth the lubricant pressure in the oil line, R-12 gas pressure at the suction end adjacent vanes 54, (FIG. 1) the compressed gas pressure in manifold 50, the R-l2 gas pressure in the lubricant sump, the amperage to the oil pump, and the temperature of the ethyleneglycol diricinoleate ester in the lubricant sump.
- TABLE Vll cants of this invention have the necessary properties overcoming the major problem of re-starting centrifugal refrigeration compressors.
- fluorocarbon refrigerant denotes hydrocarbons, usually from one to three carbon atoms compounds, wherein fluorine and chlorine have replaced all or nearly all of the hydrogen atoms. Mixtures of fluorocarbon compounds may be employed.
- diols employed for producing the diricinoleate esters comprise at least one selected from the group consisting of ethylene glycol, propylene glycol, 1,4-butanediol and 1,5- pentanediol.
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- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Organic Chemistry (AREA)
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Abstract
Description
Claims (3)
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
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US472772A US3878112A (en) | 1974-05-23 | 1974-05-23 | Lubricant-refrigerant system for centrifugal refrigeration compressors |
CA225,292A CA1036584A (en) | 1974-05-23 | 1975-04-23 | Lubricant-refrigerant system for centrifugal refrigeration compressors |
JP50061125A JPS5242921B2 (en) | 1974-05-23 | 1975-05-23 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US472772A US3878112A (en) | 1974-05-23 | 1974-05-23 | Lubricant-refrigerant system for centrifugal refrigeration compressors |
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Publication Number | Publication Date |
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US3878112A true US3878112A (en) | 1975-04-15 |
Family
ID=23876880
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US472772A Expired - Lifetime US3878112A (en) | 1974-05-23 | 1974-05-23 | Lubricant-refrigerant system for centrifugal refrigeration compressors |
Country Status (3)
Country | Link |
---|---|
US (1) | US3878112A (en) |
JP (1) | JPS5242921B2 (en) |
CA (1) | CA1036584A (en) |
Cited By (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2817031A1 (en) * | 1977-04-22 | 1978-10-26 | Westinghouse Electric Corp | CENTRIFUGAL COMPRESSOR COOLING SYSTEM |
US4172178A (en) * | 1978-05-05 | 1979-10-23 | Westinghouse Electric Corp. | Impregnated castings chemically resistant to contact with halocarbon refrigerant |
US4355960A (en) * | 1980-06-09 | 1982-10-26 | Westinghouse Electric Corp. | Compressor refrigeration system utilizing thermally stable refrigeration lubricants containing alkyl polyhalophenyl ethers |
US4535142A (en) * | 1984-07-10 | 1985-08-13 | Caschem, Inc. | High solids coatings based on diricinoleate derivatives |
US4599185A (en) * | 1985-03-25 | 1986-07-08 | Borg-Warner Corporation | Refrigerant additive and method for reducing corrosion in refrigeration systems |
US4808323A (en) * | 1986-10-01 | 1989-02-28 | Federal-Mogul Corporation | Non-deleterious dry film lubricant coating composition, rubber sealing element coated therewith; and method of |
EP0406479A1 (en) * | 1989-07-05 | 1991-01-09 | Japan Energy Corporation | Refrigeration lubricants |
US5021179A (en) * | 1990-07-12 | 1991-06-04 | Henkel Corporation | Lubrication for refrigerant heat transfer fluids |
US5211884A (en) * | 1990-05-22 | 1993-05-18 | Unilever Patent Holdings Bv | Lubricants |
US5486302A (en) * | 1991-01-17 | 1996-01-23 | Cpi Engineering Services, Inc. | Lubricant composition for fluorinated refrigerants used in compression refrigeration systems |
EP0802254A1 (en) * | 1996-04-17 | 1997-10-22 | Idemitsu Kosan Company Limited | Refrigerator oil composition |
US5801132A (en) * | 1996-04-26 | 1998-09-01 | Idemitsu Kosan Co., Ltd. | Refrigerator oil composition |
US5820777A (en) * | 1993-03-10 | 1998-10-13 | Henkel Corporation | Blended polyol ester lubricants for refrigerant heat transfer fluids |
US5851968A (en) * | 1994-05-23 | 1998-12-22 | Henkel Corporation | Increasing the electrical resistivity of ester lubricants, especially for use with hydrofluorocarbon refrigerants |
US5906769A (en) * | 1992-06-03 | 1999-05-25 | Henkel Corporation | Polyol ester lubricants for refrigerating compressors operating at high temperatures |
US5976399A (en) * | 1992-06-03 | 1999-11-02 | Henkel Corporation | Blended polyol ester lubricants for refrigerant heat transfer fluids |
US6183662B1 (en) | 1992-06-03 | 2001-02-06 | Henkel Corporation | Polyol ester lubricants, especially those compatible with mineral oils, for refrigerating compressors operating at high temperatures |
US6221272B1 (en) | 1992-06-03 | 2001-04-24 | Henkel Corporation | Polyol ester lubricants for hermetically sealed refrigerating compressors |
US20040200262A1 (en) * | 2003-04-08 | 2004-10-14 | Lenz James R. | Compact tribology tester |
US7018558B2 (en) | 1999-06-09 | 2006-03-28 | Cognis Corporation | Method of improving performance of refrigerant systems |
US20080083900A1 (en) * | 2006-09-15 | 2008-04-10 | Shrieve Chemical Products, Inc. | Synthetic refrigeration oil composition for hfc applications |
US20090205360A1 (en) * | 2008-02-20 | 2009-08-20 | Haley Paul H | Centrifugal compressor assembly and method |
US20090208331A1 (en) * | 2008-02-20 | 2009-08-20 | Haley Paul F | Centrifugal compressor assembly and method |
WO2012024808A1 (en) * | 2010-08-25 | 2012-03-01 | Panolin Ag | Ester oils |
US11486620B2 (en) * | 2017-01-25 | 2022-11-01 | Mitsubishi Electric Corporation | Refrigeration cycle apparatus |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2577888Y2 (en) * | 1992-10-22 | 1998-08-06 | 株式会社エス・アンド・テイ・スタジオ | Movable photo studio car |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1735170A (en) * | 1926-08-11 | 1929-11-12 | Westinghouse Electric & Mfg Co | Working fluid for refrigeration |
US2060728A (en) * | 1931-07-24 | 1936-11-10 | Gen Motors Corp | Refrigeration |
US2187388A (en) * | 1935-09-06 | 1940-01-16 | Gen Motors Corp | Working fluid for refrigerating apparatus |
US2852470A (en) * | 1954-10-15 | 1958-09-16 | Gen Motors Corp | Refrigeration composition |
US2926139A (en) * | 1952-11-08 | 1960-02-23 | Bayer Ag | Lubricants for refrigerating systems |
-
1974
- 1974-05-23 US US472772A patent/US3878112A/en not_active Expired - Lifetime
-
1975
- 1975-04-23 CA CA225,292A patent/CA1036584A/en not_active Expired
- 1975-05-23 JP JP50061125A patent/JPS5242921B2/ja not_active Expired
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1735170A (en) * | 1926-08-11 | 1929-11-12 | Westinghouse Electric & Mfg Co | Working fluid for refrigeration |
US2060728A (en) * | 1931-07-24 | 1936-11-10 | Gen Motors Corp | Refrigeration |
US2187388A (en) * | 1935-09-06 | 1940-01-16 | Gen Motors Corp | Working fluid for refrigerating apparatus |
US2926139A (en) * | 1952-11-08 | 1960-02-23 | Bayer Ag | Lubricants for refrigerating systems |
US2852470A (en) * | 1954-10-15 | 1958-09-16 | Gen Motors Corp | Refrigeration composition |
Cited By (44)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2817031A1 (en) * | 1977-04-22 | 1978-10-26 | Westinghouse Electric Corp | CENTRIFUGAL COMPRESSOR COOLING SYSTEM |
US4159255A (en) * | 1977-04-22 | 1979-06-26 | Westinghouse Electric Corp. | Modified castor oil lubricant for refrigerator systems employing halocarbon refrigerants |
US4172178A (en) * | 1978-05-05 | 1979-10-23 | Westinghouse Electric Corp. | Impregnated castings chemically resistant to contact with halocarbon refrigerant |
FR2442692A1 (en) * | 1978-05-05 | 1980-06-27 | Westinghouse Electric Corp | CAST METAL ORGANS |
US4355960A (en) * | 1980-06-09 | 1982-10-26 | Westinghouse Electric Corp. | Compressor refrigeration system utilizing thermally stable refrigeration lubricants containing alkyl polyhalophenyl ethers |
US4535142A (en) * | 1984-07-10 | 1985-08-13 | Caschem, Inc. | High solids coatings based on diricinoleate derivatives |
US4599185A (en) * | 1985-03-25 | 1986-07-08 | Borg-Warner Corporation | Refrigerant additive and method for reducing corrosion in refrigeration systems |
US4808323A (en) * | 1986-10-01 | 1989-02-28 | Federal-Mogul Corporation | Non-deleterious dry film lubricant coating composition, rubber sealing element coated therewith; and method of |
EP0406479A1 (en) * | 1989-07-05 | 1991-01-09 | Japan Energy Corporation | Refrigeration lubricants |
US5211884A (en) * | 1990-05-22 | 1993-05-18 | Unilever Patent Holdings Bv | Lubricants |
US5021179A (en) * | 1990-07-12 | 1991-06-04 | Henkel Corporation | Lubrication for refrigerant heat transfer fluids |
US5486302A (en) * | 1991-01-17 | 1996-01-23 | Cpi Engineering Services, Inc. | Lubricant composition for fluorinated refrigerants used in compression refrigeration systems |
US5612299A (en) * | 1991-01-17 | 1997-03-18 | Cpi Engineering Services, Inc. | Lubricant composition for fluorinated refrigerants used in compression refrigeration systems |
US6296782B1 (en) | 1992-06-03 | 2001-10-02 | Henkel Corporation | Polyol ester lubricants for refrigerator compressors operating at high temperatures |
US5906769A (en) * | 1992-06-03 | 1999-05-25 | Henkel Corporation | Polyol ester lubricants for refrigerating compressors operating at high temperatures |
US5976399A (en) * | 1992-06-03 | 1999-11-02 | Henkel Corporation | Blended polyol ester lubricants for refrigerant heat transfer fluids |
US6183662B1 (en) | 1992-06-03 | 2001-02-06 | Henkel Corporation | Polyol ester lubricants, especially those compatible with mineral oils, for refrigerating compressors operating at high temperatures |
US6221272B1 (en) | 1992-06-03 | 2001-04-24 | Henkel Corporation | Polyol ester lubricants for hermetically sealed refrigerating compressors |
US6551524B2 (en) | 1992-06-03 | 2003-04-22 | Cognis Corporation | Polyol ester lubricants, especially those compatible with mineral oils, for refrigerating compressors operating at high temperatures |
US6666985B2 (en) | 1992-06-03 | 2003-12-23 | Cognis Corporation | Polyol ester lubricants for hermetically sealed refrigerating compressors |
US5820777A (en) * | 1993-03-10 | 1998-10-13 | Henkel Corporation | Blended polyol ester lubricants for refrigerant heat transfer fluids |
US5851968A (en) * | 1994-05-23 | 1998-12-22 | Henkel Corporation | Increasing the electrical resistivity of ester lubricants, especially for use with hydrofluorocarbon refrigerants |
US6551523B1 (en) | 1995-06-07 | 2003-04-22 | Cognis Corporation | Blended polyol ester lubricants for refrigerant heat transfer fluids |
US6008169A (en) * | 1996-04-17 | 1999-12-28 | Idemitsu Kosan Co., Ltd. | Refrigerator oil composition comprising saturated hydroxy fatty acids and derivatives thereof |
EP0802254A1 (en) * | 1996-04-17 | 1997-10-22 | Idemitsu Kosan Company Limited | Refrigerator oil composition |
US5801132A (en) * | 1996-04-26 | 1998-09-01 | Idemitsu Kosan Co., Ltd. | Refrigerator oil composition |
US7018558B2 (en) | 1999-06-09 | 2006-03-28 | Cognis Corporation | Method of improving performance of refrigerant systems |
US20040200262A1 (en) * | 2003-04-08 | 2004-10-14 | Lenz James R. | Compact tribology tester |
US6817223B2 (en) * | 2003-04-08 | 2004-11-16 | Tecumseh Products Company | Compact tribology tester |
US8123974B2 (en) | 2006-09-15 | 2012-02-28 | Shrieve Chemical Products, Inc. | Synthetic refrigeration oil composition for HFC applications |
US20080083900A1 (en) * | 2006-09-15 | 2008-04-10 | Shrieve Chemical Products, Inc. | Synthetic refrigeration oil composition for hfc applications |
US8709276B2 (en) | 2006-09-15 | 2014-04-29 | Shrieve Chemical Products, Inc. | Synthetic refrigeration oil composition for HFC applications |
EP2095039A1 (en) * | 2006-09-15 | 2009-09-02 | Shrieve Chemical Products, Inc. | A synthetic refrigeration oil composition for hfc applications |
EP2095039A4 (en) * | 2006-09-15 | 2011-01-12 | Shrieve Chemical Products Inc | A synthetic refrigeration oil composition for hfc applications |
US8268188B2 (en) | 2006-09-15 | 2012-09-18 | Shrieve Chemical Products, Inc. | Synthetic refrigeration oil composition for HFC applications |
US20090208331A1 (en) * | 2008-02-20 | 2009-08-20 | Haley Paul F | Centrifugal compressor assembly and method |
US20120087815A1 (en) * | 2008-02-20 | 2012-04-12 | Haley Paul H | Centrifugal compressor assembly and method |
US8037713B2 (en) * | 2008-02-20 | 2011-10-18 | Trane International, Inc. | Centrifugal compressor assembly and method |
US8627680B2 (en) * | 2008-02-20 | 2014-01-14 | Trane International, Inc. | Centrifugal compressor assembly and method |
US20090205360A1 (en) * | 2008-02-20 | 2009-08-20 | Haley Paul H | Centrifugal compressor assembly and method |
US9353765B2 (en) | 2008-02-20 | 2016-05-31 | Trane International Inc. | Centrifugal compressor assembly and method |
US9556875B2 (en) | 2008-02-20 | 2017-01-31 | Trane International Inc. | Centrifugal compressor assembly and method |
WO2012024808A1 (en) * | 2010-08-25 | 2012-03-01 | Panolin Ag | Ester oils |
US11486620B2 (en) * | 2017-01-25 | 2022-11-01 | Mitsubishi Electric Corporation | Refrigeration cycle apparatus |
Also Published As
Publication number | Publication date |
---|---|
CA1036584A (en) | 1978-08-15 |
JPS5121213A (en) | 1976-02-20 |
JPS5242921B2 (en) | 1977-10-27 |
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