CA1148805A - Device for automatic addition of a corrosion inhibitor to a coolant system - Google Patents
Device for automatic addition of a corrosion inhibitor to a coolant systemInfo
- Publication number
- CA1148805A CA1148805A CA000339377A CA339377A CA1148805A CA 1148805 A CA1148805 A CA 1148805A CA 000339377 A CA000339377 A CA 000339377A CA 339377 A CA339377 A CA 339377A CA 1148805 A CA1148805 A CA 1148805A
- Authority
- CA
- Canada
- Prior art keywords
- corrosion inhibitor
- inhibitor
- hollow stem
- openings
- hydrometer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
- F01P11/00—Component parts, details, or accessories not provided for in, or of interest apart from, groups F01P1/00 - F01P9/00
- F01P11/06—Cleaning; Combating corrosion
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N9/00—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity
- G01N9/10—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by observing bodies wholly or partially immersed in fluid materials
- G01N9/12—Investigating density or specific gravity of materials; Analysing materials by determining density or specific gravity by observing bodies wholly or partially immersed in fluid materials by observing the depth of immersion of the bodies, e.g. hydrometers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01P—COOLING OF MACHINES OR ENGINES IN GENERAL; COOLING OF INTERNAL-COMBUSTION ENGINES
- F01P11/00—Component parts, details, or accessories not provided for in, or of interest apart from, groups F01P1/00 - F01P9/00
- F01P11/06—Cleaning; Combating corrosion
- F01P2011/066—Combating corrosion
- F01P2011/068—Combating corrosion chemically
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Combustion & Propulsion (AREA)
- Life Sciences & Earth Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Preventing Corrosion Or Incrustation Of Metals (AREA)
Abstract
DEVICE FOR AUTOMATIC ADDITION OF A CORROSION
INHIBITOR TO A COOLANT SYSTEM
Abstract:
A device for the automatic addition of corrosion inhibitor into an automobile coolant system when the coolant mixture is diluted by water having an undesirable level of corrosiveness. The devise is in the form of a hydrometer (10) having a hollow stem (11) adapted to receive a quantity of a corrosion inhibitor (16) and having openings (15) in the stem wall allowing contact of the liquid in the coolant system with the corrosion inhibitor when the specific gravity of the coolant liquid decreases below a predetermined level.
INHIBITOR TO A COOLANT SYSTEM
Abstract:
A device for the automatic addition of corrosion inhibitor into an automobile coolant system when the coolant mixture is diluted by water having an undesirable level of corrosiveness. The devise is in the form of a hydrometer (10) having a hollow stem (11) adapted to receive a quantity of a corrosion inhibitor (16) and having openings (15) in the stem wall allowing contact of the liquid in the coolant system with the corrosion inhibitor when the specific gravity of the coolant liquid decreases below a predetermined level.
Description
~B~5 DEVIC~ FOR AUTO.~I~.~IC ADD-rTION OF A CORROSION
.... . . . . .. .
INHIBITOR TO A COOLAM~ S~ST~M
. .
Descri~t~on -The cooling system of an automotive vehicle ;nvolves the circulation of a li~uid coolant through the enqlne ~lock of an ;nternal combust~on englne and then through a heat exchanger or radiator ~y a nump operated ~ the engine. T~e coolant removes heat from t~e engine block during operation, and the radiator cools the heated coolant by a forced air flow through the radiator and around a plurality of tubes therein carr~Iing the coolant. In view of the temperature extremes in many parts of the countr~, the conventional coolant is an approximately 50-50 mixture of ethylene glycol with water.
Presently, automotive radiators are formed of copper and/or bras-s, and the ethylene glycol, ~ith a s~all percentage of diethylene glycol, is diluted ~7ith water to make a 50% or lower concentration of glycol depending on the desired freezing point protection.
?lost manufacturers or distributors of ethylene glycol also add corrosion inhibitors to the solution; ~hich inhibitors are usually a mixture of one or more lnorganic salts, such as phosphates, horates, nitrates, nitrites, 2S silicates and arsenates, and an organic compound, such as henzotriazole, tolyltriazole, or mercapto~enzothiazole, to prevent copper corrosion. ~he solution ls generally buffered ,o a pEr of 8~10 to reduce ixon corrosion and to neutralize any glycolic acid formed in the oxidation 30 OI ethylene gl~col.
Most manufacturers of ethylene ~lycoi recommend a maximum of one or two years' service for th~ir antiL~eeZe, however, the average car owner does not follow the owner's ~anual instructions to maintain -2'' F. pro-tection or check the coolant -to see if it is rusty or dirty. r~any owners only add water when the antifreeze is lost through leakage or hose breakage. In normal passenger car service, 25% of the cars require coolant system servicing a~ter one year; and after two years, this rises to 50~. Wit~ a conventional copper-brass radiator, it is extremely important that the antifreeze mixture contains 50-55~ of the correctly inhibited ethylene glycol. A reduction to 33~O ethylene ~lycol 67% water will increase metal corrosion significantly.
This is especially important with higher temperature coolant systems which are becoming more common with the increased use of emission controls.
At the present time, a concerted effort is being made by the automobile manufacturers to increase gas mileage to federally legislated standards by size and weight reduction of the automobiles. To provide weight reduction, lightweight metals and plastics are heing substituted for present day heavier metal components.
One such area is in the use of aluminum in place of copper and brass for automotive radiators. Aluminum provides a high heat transfer capability, however, there have been problems in dimensional stability, corrosion resistance, and in the manufacture of the aluminum structure.
In particular, the corrosion problems discussed previously are considerably accentuated for aluminum radiators and, where corrosive water is used to replace the proper ethylene glycol-water mixture due to leakage 3~3 or hose breakage during operation of the vehicle, corrosion of the aluminum radiator is consi~erably more rapid and destructive. Thus, the present invention provides for automatic replacement of the corrosion inhibitor to avoid the corrosion problems.
The present invention comprehends the provision of a device designed to automatically add a suitable corrosion inhi~itor to the coolant in an engine cooling system in the event t~at the operator replaces lost ethylene glycol solution ~ith water. The device is designed as a hydrometer with a solid or liquid in-hibitor in the hollow upper tube or stem above the weighted end. The hydrometer could be placed in the coolant overflow tank or, if small enough, in the radiator tank. As the specific gra~ity of the coolant decreases due to the addition of water, the hydrometer tube will gradually drop until the inhibitor is contacted by the coolant solution.
The present invention also comprehends the provision of a device to add corrosion inhibitor automatically to a coolant solution where a hydrometer has an upper tube with small openin~s therein at a level opposite the corrosion inhibitor. To provide for gradual additions, separators may be placed between levels of corrosion inhibitor so that the device will be operative over an extended period of time.
One way;of carrying out the invention is described in detail below with reference to drawings which illustrate only one specific embodiment, in which:-J/~ 3 Figure l is a side elevational ~iew with aportion broken away of a hydrometer containing corrosion inhibitor.
Figure 2 is a side elevational vlew with a portion broken away of the hydrometer with separakors between inhibitor layers.
Referring more particularly ~o the disclosure in the drawin~ wherein are shown illustrative embodiments of the present invention, Figure 1 discloses a hydrometer lO of conventional shape with an elongated tubular stem ll terminating in an enlarged bulbous lower end 12 wherein a suita~le weight 13, such as steel shot, is located.
The tubular stem has a graduated scale 14 thereon to indicate speci~ic gravity of the coolant and a plurality of small openings 15 in the stem generally opposite a quantity of a suitable corrosion inhibitor 16 located within the stem and resting on a glass separator 17. Assuming that the hydrometer lO is placed in the overflow tank for the radiator (not shown) where temperatures are unlikely to exceed 200 F., at the proper specific gravity for the ethylene glycol-water mix, the stem ll containing the corrosion inhibitor will not contact the coolant. As water is added to the coolant system to replace the loss of coolant, the hydrometer will gradually drop as the specific gravity decreases until the coolant can pass through the openings 15 to contact the inhi~itor 16 and a portion of it or all of it will dissolve, depending on the contact area, which in turn depends on the water-ethylene glycol concentration.
J'~5 As more specifically shown in the table, the speci~ic gravity o~ the coolant will vary with con-centration and temperature:
TAsLE I
S Volume Percent Solution Specific Gravity t/60F. in air Ethylene Freezing Pt. O O
GlycolWater F. 60F. 150 F.200 F.
__ 50-33.5 . 1.080 1.05G1.030 60-ll.0 1.064 1. 0371.018 10 30 70 ~.3 1.050 1. 0241.005 8015.7 1.034 1.0100.992 9024.6 1.020 0.9970,980 0 10032.0 1.004 0.9820. 966 Considering the data in this table, assuming the 15 hydrometer lO is located in the overflow tank at approximately 200F., a 50-50 mixture ~Till have a specific gravity of 1.030 and no inhibitor will con-tact the coolant. However, if the specific gravity decreases to 1. 020 through the addition of water, the hydrometer 20 will drop allowing part of the solid inhibitor to dissolve. As the coolant dissolves the solid material, the weight of the hydrometer may initially increase and then decrease as the solid dissolves and is replaced by water. To overcome this, a separator 17 is located 25 between each level 18,19,20 of inhibitor as shown in Figure 2.
The weight of the inhibitor 16 is dependent on its solid density. ~ixed powdered inhibitors can be compacted to increase their density by compression molding. For 30 an average coolant volume of about 15 liters, requiring -.
0.1% inhibitor for me-tal protection, the weight of inhibitor needed ~ill be 15 grams. To increase the inhibitor weight, it is necessary to increase the cross sectional area of t~e hydrometer. For example, to illustrate a simple case, assume the hydrometer is a cylinder which sinks to a depth "a" in water and a depth "x" in an ethylene glycol-water mixture of 50-50.
Let the weight of the cylinder be m and its cross sectional area A.
lO Then mg = AapOg = Axpg where pO = density of water, p = density of ethylene glycol mixture and g = the acceleration due to gravity.
This equation shows that as m increases, A must increase for everything else to remain the same. In the hydro-meters of both Figures l and 2, a rubber stopper 21 closes the open end of the stem 11.
.... . . . . .. .
INHIBITOR TO A COOLAM~ S~ST~M
. .
Descri~t~on -The cooling system of an automotive vehicle ;nvolves the circulation of a li~uid coolant through the enqlne ~lock of an ;nternal combust~on englne and then through a heat exchanger or radiator ~y a nump operated ~ the engine. T~e coolant removes heat from t~e engine block during operation, and the radiator cools the heated coolant by a forced air flow through the radiator and around a plurality of tubes therein carr~Iing the coolant. In view of the temperature extremes in many parts of the countr~, the conventional coolant is an approximately 50-50 mixture of ethylene glycol with water.
Presently, automotive radiators are formed of copper and/or bras-s, and the ethylene glycol, ~ith a s~all percentage of diethylene glycol, is diluted ~7ith water to make a 50% or lower concentration of glycol depending on the desired freezing point protection.
?lost manufacturers or distributors of ethylene glycol also add corrosion inhibitors to the solution; ~hich inhibitors are usually a mixture of one or more lnorganic salts, such as phosphates, horates, nitrates, nitrites, 2S silicates and arsenates, and an organic compound, such as henzotriazole, tolyltriazole, or mercapto~enzothiazole, to prevent copper corrosion. ~he solution ls generally buffered ,o a pEr of 8~10 to reduce ixon corrosion and to neutralize any glycolic acid formed in the oxidation 30 OI ethylene gl~col.
Most manufacturers of ethylene ~lycoi recommend a maximum of one or two years' service for th~ir antiL~eeZe, however, the average car owner does not follow the owner's ~anual instructions to maintain -2'' F. pro-tection or check the coolant -to see if it is rusty or dirty. r~any owners only add water when the antifreeze is lost through leakage or hose breakage. In normal passenger car service, 25% of the cars require coolant system servicing a~ter one year; and after two years, this rises to 50~. Wit~ a conventional copper-brass radiator, it is extremely important that the antifreeze mixture contains 50-55~ of the correctly inhibited ethylene glycol. A reduction to 33~O ethylene ~lycol 67% water will increase metal corrosion significantly.
This is especially important with higher temperature coolant systems which are becoming more common with the increased use of emission controls.
At the present time, a concerted effort is being made by the automobile manufacturers to increase gas mileage to federally legislated standards by size and weight reduction of the automobiles. To provide weight reduction, lightweight metals and plastics are heing substituted for present day heavier metal components.
One such area is in the use of aluminum in place of copper and brass for automotive radiators. Aluminum provides a high heat transfer capability, however, there have been problems in dimensional stability, corrosion resistance, and in the manufacture of the aluminum structure.
In particular, the corrosion problems discussed previously are considerably accentuated for aluminum radiators and, where corrosive water is used to replace the proper ethylene glycol-water mixture due to leakage 3~3 or hose breakage during operation of the vehicle, corrosion of the aluminum radiator is consi~erably more rapid and destructive. Thus, the present invention provides for automatic replacement of the corrosion inhibitor to avoid the corrosion problems.
The present invention comprehends the provision of a device designed to automatically add a suitable corrosion inhi~itor to the coolant in an engine cooling system in the event t~at the operator replaces lost ethylene glycol solution ~ith water. The device is designed as a hydrometer with a solid or liquid in-hibitor in the hollow upper tube or stem above the weighted end. The hydrometer could be placed in the coolant overflow tank or, if small enough, in the radiator tank. As the specific gra~ity of the coolant decreases due to the addition of water, the hydrometer tube will gradually drop until the inhibitor is contacted by the coolant solution.
The present invention also comprehends the provision of a device to add corrosion inhibitor automatically to a coolant solution where a hydrometer has an upper tube with small openin~s therein at a level opposite the corrosion inhibitor. To provide for gradual additions, separators may be placed between levels of corrosion inhibitor so that the device will be operative over an extended period of time.
One way;of carrying out the invention is described in detail below with reference to drawings which illustrate only one specific embodiment, in which:-J/~ 3 Figure l is a side elevational ~iew with aportion broken away of a hydrometer containing corrosion inhibitor.
Figure 2 is a side elevational vlew with a portion broken away of the hydrometer with separakors between inhibitor layers.
Referring more particularly ~o the disclosure in the drawin~ wherein are shown illustrative embodiments of the present invention, Figure 1 discloses a hydrometer lO of conventional shape with an elongated tubular stem ll terminating in an enlarged bulbous lower end 12 wherein a suita~le weight 13, such as steel shot, is located.
The tubular stem has a graduated scale 14 thereon to indicate speci~ic gravity of the coolant and a plurality of small openings 15 in the stem generally opposite a quantity of a suitable corrosion inhibitor 16 located within the stem and resting on a glass separator 17. Assuming that the hydrometer lO is placed in the overflow tank for the radiator (not shown) where temperatures are unlikely to exceed 200 F., at the proper specific gravity for the ethylene glycol-water mix, the stem ll containing the corrosion inhibitor will not contact the coolant. As water is added to the coolant system to replace the loss of coolant, the hydrometer will gradually drop as the specific gravity decreases until the coolant can pass through the openings 15 to contact the inhi~itor 16 and a portion of it or all of it will dissolve, depending on the contact area, which in turn depends on the water-ethylene glycol concentration.
J'~5 As more specifically shown in the table, the speci~ic gravity o~ the coolant will vary with con-centration and temperature:
TAsLE I
S Volume Percent Solution Specific Gravity t/60F. in air Ethylene Freezing Pt. O O
GlycolWater F. 60F. 150 F.200 F.
__ 50-33.5 . 1.080 1.05G1.030 60-ll.0 1.064 1. 0371.018 10 30 70 ~.3 1.050 1. 0241.005 8015.7 1.034 1.0100.992 9024.6 1.020 0.9970,980 0 10032.0 1.004 0.9820. 966 Considering the data in this table, assuming the 15 hydrometer lO is located in the overflow tank at approximately 200F., a 50-50 mixture ~Till have a specific gravity of 1.030 and no inhibitor will con-tact the coolant. However, if the specific gravity decreases to 1. 020 through the addition of water, the hydrometer 20 will drop allowing part of the solid inhibitor to dissolve. As the coolant dissolves the solid material, the weight of the hydrometer may initially increase and then decrease as the solid dissolves and is replaced by water. To overcome this, a separator 17 is located 25 between each level 18,19,20 of inhibitor as shown in Figure 2.
The weight of the inhibitor 16 is dependent on its solid density. ~ixed powdered inhibitors can be compacted to increase their density by compression molding. For 30 an average coolant volume of about 15 liters, requiring -.
0.1% inhibitor for me-tal protection, the weight of inhibitor needed ~ill be 15 grams. To increase the inhibitor weight, it is necessary to increase the cross sectional area of t~e hydrometer. For example, to illustrate a simple case, assume the hydrometer is a cylinder which sinks to a depth "a" in water and a depth "x" in an ethylene glycol-water mixture of 50-50.
Let the weight of the cylinder be m and its cross sectional area A.
lO Then mg = AapOg = Axpg where pO = density of water, p = density of ethylene glycol mixture and g = the acceleration due to gravity.
This equation shows that as m increases, A must increase for everything else to remain the same. In the hydro-meters of both Figures l and 2, a rubber stopper 21 closes the open end of the stem 11.
Claims (9)
1. A device for the automatic addition of corrosion inhibitor to a coolant system, comprising a hydrometer having an elongated hollow stem with an enlarged weighted lower end, the hollow stem having an upper portion adapted to receive a corrosion inhibitor, said stem having a plurality of small openings opposite the corrosion inhibitor to allow ingress of liquid therein to dissolve the inhibitor when the position of the hydrometer drops relative to the liquid level as the specific gravity of the liquid decreases.
2. A device as set forth in Claim 1, in which said openings are spaced axially along the hollow stem in annular rows so as to dissolve layers of inhibitor sequentially.
3. A device as set forth in Claim 2, including separators in said hollow stem to divide the inhibitor into several equal portions with an annular row of openings opposite each portion.
4. A device as set forth in Claim 3, in which each layer of corrosion inhibitor is compacted to increase its density.
5. A device as set forth in Claim 1, in which said hollow stem is open at the upper end, and a resilient closure is inserted in the open upper end.
6. A method of adding a corrosion inhibitor to an automotive coolant system comprising the steps of providing a floatable hydrometer with an elongated hollow stem having corrosion inhibitor therein and a plurality of openings in the stem, positioning the hydrometer in the coolant system so that the openings will be above the fluid level when the specific gravity of the fluid is at an acceptable valve, and releasing the corrosion inhibitor into the fluid due to the openings moving under the fluid level when the specific gravity of the fluid decreases.
7. The method of adding corrosion inhibitor as set forth in Claim 6, including the step of locating said openings at spaced intervals along the hollow stem so as to add differing quantities of inhibitor depending on the position of the hydrometer in the fluid.
8. The method of adding corrosion inhibitor as set forth in Claim 6, including the step of separating the corrosion inhibitor in the hollow stem into distinct quantities with openings communicating with each quantity.
9. The method of adding corrosion inhibitor as set forth in Claim 8, including the step of partitioning said hollow stem to form the separate quantities of inhibitor.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US96422578A | 1978-11-27 | 1978-11-27 | |
| US964,225 | 1978-11-27 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1148805A true CA1148805A (en) | 1983-06-28 |
Family
ID=25508277
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000339377A Expired CA1148805A (en) | 1978-11-27 | 1979-11-07 | Device for automatic addition of a corrosion inhibitor to a coolant system |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JPS5598612A (en) |
| BR (1) | BR7907615A (en) |
| CA (1) | CA1148805A (en) |
| FR (1) | FR2442337A1 (en) |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1806536A (en) * | 1931-05-19 | bolton | ||
| BE505120A (en) * | 1950-10-03 | |||
| DE2328986C2 (en) * | 1973-06-07 | 1983-01-05 | John D. St. Paul Minn. Skildum | Device for internal combustion engines for their internal protection against corrosion |
| US3952761A (en) * | 1974-03-25 | 1976-04-27 | Donald Friedland | System for controlling density of liquids |
-
1979
- 1979-11-07 CA CA000339377A patent/CA1148805A/en not_active Expired
- 1979-11-23 BR BR7907615A patent/BR7907615A/en unknown
- 1979-11-26 FR FR7929097A patent/FR2442337A1/en active Pending
- 1979-11-27 JP JP15345979A patent/JPS5598612A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| BR7907615A (en) | 1980-08-05 |
| FR2442337A1 (en) | 1980-06-20 |
| JPS5598612A (en) | 1980-07-26 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |