US2636834A - Asphaltic-composition application - Google Patents

Description

April 28, 1953 D. N. MYERS 2,636,834

ASPHALTIC-COMPOSITION APPLICATION Filed Feb. 15, 195o ,gl/0 f IEW l d l k IN VEN TOR. 2A V/p M #V565 MWJMQ ,9770 mvE 76 Patented Apr. 28, 1953 ASPHALTIC-COMPOSITION APPLICATION David N. Myers, Shaker Heights, Ohio, assigner to Byerlyte Corporation', Cleveland, Ohio, a

corporation of Ohio Application February 15, 1950, Serial No. 144,296

4 Claims.

, Efforts have been made to form a layer of asphalt mastic compounds on sheet metal by troweling or'y 4doctoring into position. Compounds of this'character are rather critical, in that they involve mixtures of finelyl divided mineral filler and -asphaltic binder and a liquid, either a volatile solvent or water emulsion, and by reason of specific gravity differences thereis considerable tendency for the mineral matter to settle out before application to the desired surface. Some attempts have been made to apply the compound'by forcing it by compressed air through a flexible hose and a spray gun, but this has been handicapped by the plastic character of the material. Resort has been had accordingly to applying by barrel pump method in which the material is pumped directly from thel shipping drum in which it is handled, by a piston type pump. Here again the heavy mineral matter has tended to-settle such that stratification in the drum in which the material is shipped, has resulted in a thinner fluid at the top and an extra heavy mastic at the bottom of the drum, thereby causingy non-uniformity. And, in such use of a reciprocating pump there has been an objectionable pulsation or irregu-` larity in the streamof the material as attempted to be. appliedl through a spray-gun type. of device. Besides,` the abrasive mineral matter has had the objectionof quickly damaging such type of pump. f l In .the present invention, asphalt mastic with ahigh content of mineral filler maybe successfully applied to metal'surfaces in thickness as desired, and with` minimal difficulty from the apparatus standpoint. .0ther objects land advantages ofthe invention willn appear from the following description.

To the accomplishment of therforegoing and related ends, said invention then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative,r however, of but a few of the various ways in which the principle of apparatus 2 finely divided mineral and asphalt. The mineral matter may be ground asbestos, sand, limestone dust, silicate flour, mica, slate flour, asbestine, and the like. The proportion of mineral filler may be 25 to 75 per cent by weight. Advantageously there may be about 15 per cent of the asphalt binder together with other mineral powders as mentioned, the total of such asbestos and other mineral then being advantageously 40-65 per cent. The asphalt binder in general may have a softening point of 110-150,

and penetration 20-120, and may be of steam reduced type, or steam vacuum type or semi-oxidized type. The asphalt mixture may involve in some cases a volatile solvent, and in others a water emulsion. Both types are thus composed of asphalt, mineral fillers, and liquid carrier. In the volatile solvent type, the asphalt is thinned with a naphtha such as rubber solvent naphtha, V. M. & P. naphtha, mineral spirits, etc., in general the initial boiling point being around 12o-170 as in the rubber solvents or around 200 as in V. M. & P. and the end point in the case of rubber solvents may be around 220-2'70 F., or about 300 in case of V. M. & P. Various blends of solvents can be employed, the initial boiling point should not be above that of gasoline and the end point not above about 380. The solvent is applied with the asphalt in the range generally of about 40 to 65 per cent by weight of asphalt and 35 to 60 per cent of solvent. In the emulsion type of compound, the asphalt is dispersed in water, the water being the continuous phase. Either the mechanically stabilized or the chemically stabilized'form of emulsion may be employed. In the mechanically stabilized type, the dispersing medium, usually of clay or bentonite, and in the chemically stabilized type, a soap solution such as of rosin, tall oil soap, or alkaline agent such as trisodium phosphate, etc., are used as dispersing medium. Whether the solvent or water type of asphalt plastic compound is employed, it usually consists of 10 to 25 per cent of liquid carrier, l5 to 20 per cent of asphalt binder and 25 to 70 per cent of mineral fillers.

As seen, the high specic gravity of the mineral ller as compared with the rest ofthe composition, introduces a tendency to segregation, and in the present invention this is particularly dealt with such that the composition is `supplied in uniformity at the point of application. .And thus, in usages such as for sound-deadening in the automotive industries, satisfactory layers of uniform character may be had on portions of auto parts, such as interior surface of doors,

trunks, quarter panels, tow boards and under surfaces of fenders, etc., to dampen vibration and to lessen noise. And similarly with such sheet metal porcelain-ware as sinks, tubs, cabinets, etc.; and in general with sheet metal surfaces.

In order to uniformize the asphaltic and mineral compound, as customarilyy available in shipping drums or metal barrels, the `drums are dumped into an agitating zone, and the material thence is kept in motion to its point of application, and with avoidance of centrifugal force.

at any point to favor segregational separation. Furthermore, this kind ofV material is thixotropic. In a state of quiescence it is'quiterm, but it becomes thinner on proper agitation. Thus, the material as received in the. drums for instance is first introduced into a mixer 2, and preferably this is of pug mill type, such formof structure being especially well suited for uniformizing and handling the mastic-r pasty material concerned. In the form illustrated, the mixer mayy have a shaftv 3 driven by suitable means,` for instance a motor 4, and carried on' theishaft are arms 5 which carry blades 6, which may be of arcuate form to move under and lift the'material in its general stirring action. Desirably, the agitating chamber may havea temperature-control jacket, such as steam jacket 1.

Ordinarily, theasphait mastic should be applied at' a temperature of SII-90 and if the material as received in the shipping drums is outside-such range, the temperature may thus'be adjusted to desired point by the temperature.- control jacket. into afirt-her zone I0 in which there isa rotor I'I of sinuous or rounded helical form presenting' gentle undulating surfaces, which by reason of the'genelal screw-character agitate' the materialand forward it at the same time; with the rotor is a stator lining or sleeve I2 in the casing I3, and a peculiarity is that the shaping of the interior surface of the stator involves a successive series of constrictions and expansions, thus in cooperation with the motion of the rotor providing a progression-succession of cavitation action, the material passing' through points' of constriction' into zones of' expansion. Liquefaction of the' thixotropic material is? further' favored by this action` and maintained` in thorough agitation and it is forwarded to point of application. The stator portion I2 isi also peculiarin being formed of resilientmaterial, such as synthetic rubber whichv is not affected" by asphalt. There is thus suiiicient effective contact at points between the' rotor and statorto favor sealing against back-slip of material, and allow ample cavitation for the material to rush into', and at the same time such surfaces are not detrimentally affected by the highly abrasive mineral particles. A conduit I5 directs the stream of material to point of application, and conveniently this may involve spray guns I6 of ample size, on the lines of hand-trigger controlled nozzles available. Such nozzles may be connectedto the conduit I 5 by flexible hose. I1. The materialis maintained in active circulation throughout. The conduit, inreduced size, beyond the point of sprayer connection, has a return section I 8 leading back to theagitating zone 2.r

y yIn some cases, if it is desired, some addition of solvent may be introduced at the agitating zoneY 2, but in any event the material is here thoroughly uniformized, and the effectivek agita- The agitating'zone 2 discharges Co-a-cting l 4 tion is carried through in its transit to the point of application, especially by the progressioncavitating in the tubular passageway I 2. And whether the material is freshly made up or may have been stored in drums for a considerable time with resultant segregation and settling together with stiffening, the asphaltic mastic is thoroughly unifrmizedl'a'nd" in such: condition supplied at point' of application.

ther modes of applying the principle of the invention may be employed, change being made asregards they details described, provided the features stated in any of the following claims or the equivalent of such be employed.

Iy therefore'particularly point out and distinctly claim as my invention:

1. In the application of materials having a tendency to settle out comprising a uniform mixture of fluent asphalt of penetration 20-120 and inert mineral particles with higher specific gravities` thanV said fluent i asphalt, as deadener layers on metalisurfaces and theilike; the process which' comprises the" steps.' of introducing the uniform mixture' intoY a confined stream, andpassing the mixture in theconfmed stream and whilev it is in said stream, subjecting it to alternate successive" compression and expansion, said expansion effecting" eavitation' in the stream' whereby the uniformity of the mixture is maintained in the stream, andy spreading? the mixtureA on a metal surface;

2. Inl the application of materials having a; tendency to settle out. comprising a mixture of fluent asphalt of penetration 2'0"-l2'0` and inert mineral particles with higher specific gravities than said'fluent" asphalt, as deadener layers'on metal surfaces and-the like, the process which comprises theA steps of subjecting the mixtureto non-centrifugal'v agitation, and passing the mixturein a' confined stream' and while it is in said stream, subjectingit to alternate successive compression and expansion, said expansion effecting cavita'tionin-the stream whereby the uniformity ofthe mixture is maintained in the stream', and spreading the mixture on a metal surface.

3'. In the application of materials having a' tendency to settle out comprising'a mixture o1' fluentv asphalt of vpenetrationl 20-12'0` and inert mineral particles with higher specificl gravities than" said" fluid asphalt; as deadener layers on metal surfaces and the like, the process which comprises the steps of subjecting the mixture to non-centrifugal agitation, and passing ther mixture" in a confined stream and while it is' in said stream; subjecting lit to alternate successive compre'ssionand expansion, said expansion effecting cavitation in the' stream whereby-'theiuniformity of the mixture ismaintainedin the stream, and spreadingJ the mixture. on. a metalv surface while rea-circulating the unused mixture back .to the zone ofagitation.

4. In the applicationn of materials having. a tendency tovsettle outcomprising a uniform mixture'of fluent asphalt of penetration 20.-120 and inert mineral particles with higher specific gravities than said fluent-asphalt, as deadener layers on metal surfaces and the-like, the process which comprises the'steps'. ofi introducing the uniform mixture into a confined stream, and passing theA mixturein the confined stream andl while-it is in said stream, subjecting it to alternate successive compression andV expansion, said vexpansion effecting cavitatio'n in the stream whereby the uniformity' of the mixture is' maintained in 6 the stream, ana spray-applying the mixture onto Number Name Date almetal surface. 2,123,604 Johnson July 12, 1938 A DAVID N. MYERS. 2,145,027 McGrew Jan. 24, 1939 2,176,128 Fife Oct. 17, 1939 References Cited in the le of this patent r 2,464,011 Wade Mar, 8, 1949 UNITED STATES PATENTS o 2,464,771 Van Guelpen Mar. 15, 1949 Number Name Date FOREIGN PATENTS 1,829,661 Krautzberger Oct. 27, 1931 2,047,772 Eckert July 14, 1936 Number Country Date 2,112,927 Pierre Apr. 5, 1938 1U 400,508 Great Britain Oct. 26, 1933

Claims (1)

1. IN THE APPLICATION OF MATERIALS HAVING A TENDENCY TO SETTLE OUT COMPRISING A UNIFORM MIXTURE OF FLUENT ASPHALT OF PENETRATION 20-120 AND INERT MINERAL PARTICLES WITH HIGHER SPECIFIC GRAVITIES THAN SAID FLUENT ASPHALT, AS DEADENER LAYERS ON METAL SURFACES AND THE LIKE, THE PROCESS WHICH COMPRISES THE STEPS OF INTRODUCING THE UNIFORM MIXTURE INTO A CONFINED STREAM, AND PASSING THE MIXTURE IN THE CONFINED STREAM AND WHILE IT IS IN SAID STREAM, SUBJECTING IT TO ALTERNATE SUCCESSIVE COMPRESSION AND EXPANSION, SAID EXPANSION EFFECTING CAVITATION IN THE STREAM WHEREBY THE UNIFORMITY OF THE MIXTURE IS MAINTAINED IN THE STREAM, AND SPREADING THE MIXTURE ON A METAL SURFACE.

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