US3179377A - Injector-mixer, especially for forest fire control - Google Patents

Injector-mixer, especially for forest fire control Download PDF

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US3179377A
US3179377A US46545A US4654560A US3179377A US 3179377 A US3179377 A US 3179377A US 46545 A US46545 A US 46545A US 4654560 A US4654560 A US 4654560A US 3179377 A US3179377 A US 3179377A
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conduit
injector
mixer
disposed
fire control
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Orr Robert St John
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    • AHUMAN NECESSITIES
    • A62LIFE-SAVING; FIRE-FIGHTING
    • A62CFIRE-FIGHTING
    • A62C99/00Subject matter not provided for in other groups of this subclass
    • A62C99/009Methods or equipment not provided for in groups A62C99/0009 - A62C99/0081
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02ATECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A40/00Adaptation technologies in agriculture, forestry, livestock or agroalimentary production
    • Y02A40/10Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in agriculture
    • Y02A40/28Adaptation technologies in agriculture, forestry, livestock or agroalimentary production in agriculture specially adapted for farming

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  • This invention relates to'improvementsiin mixers which operate on the injector principle and which are useful in The improvements constituting the subject invention are particularly eflicient for the formation and dispensing under high pressure fluid flow conditions of fire retardant slurries for forest fire control.
  • An object of the. invention is to provide, in a liquidsolid injector-mixer having. a horizontally'disposed first conduit'for fluid flow and a vertically disposed second conduit for solid flow intosaid first conduit, means for so controlling high pressure fluid flow through said first conduit that none. of said fluid will be received into the A further object of the invention is to provide, in a liquid-solid injector-mixer as above described, a fluid flow control nozzle immediately adjacent the juncture between said first and second conduits which is eifective to control the flow of fluidpastthe' inlet'of said second conduit so that no residual fluid will remain in the inlet end of said second conduit for commingling with'the solids therein prior to the entry of. said solids into said first conduit.
  • Still a furtherobject of the invention is to provide a liquid-solid injector-mixer as described embodying a control valve for each of said conduits and control means ineluding a single' control lever for conjointly operating said valves.
  • FIG. 1 is a general view in perspective of a complete system embodying the, improved injector-mixer of the invention
  • FIG. 2 mixer of the assemblage system of FIG. 1;
  • FIG. 3 is a view in side elevation of the injector-mixer of FIG. 2; Y
  • FIG. 4 is a view in section taken along lines 44 of FIG. 2, but showing both the fluid and solid control valves in open position;
  • FIG. 5 is a view partly in section and partly in side elevation showing the fluid control valve in 'a partially closed condition and the solid control valve in a fully closed condition;
  • FIG. 6 is a detail view in section taken along lines 66 of FIG. 4;
  • FIG. 7 is a view in perspective of the fluid flow control.
  • FIG. 1 The assemblage of FIG. 1 comprises a supporting framework 10 comprising top, bottom, and side support elements indicated, respectively, by 12, 14 and16, solids fed hopper 18, the injector-mixer secured to bottom support elements 14, a pressure gauge 22 whereby the fluid pressure within the injector-mixer 20' may be checked, and discharge line 23.
  • FIG. 1 is an enlarged view in top plan of the injector- Hopper 18 is connected to the upper end of solids feed conduit 32 by the lower end of conduit 24 is a horizontal" gate valve 36 having feed-through orifice 38 adapted to be disposed in and out of registry with the discharge end of conduit 24 and with solids feed aperture 40 in conduit 32.
  • Conduit 32 (see FIG. 4) is comprised of multiple sections 42, 44 and*46 which are mutually secured in fluid sealed relationship by connectonmembers 48, 50 and sealing elements 52, 54 and '56.
  • the inlet to pressure gauge 22 is shown at 57 in FIG. 4.
  • a ball valve element 64 Rotatably'disposed between complemental semi-spherical surfaces 58 and 60, formed, respectively, on the in terior of conduit section .44 and insert member 62 for said conduit section, is a ball valve element 64 having a dia metral passageway 66 adapted, upon selective movement of said valve element 64, to be moved into and out of registry with the passageway of conduit 32.
  • I Section 42 of conduit 32' is counter-bored'to receive a sleeve '68, said sleeve being provided with an enlarged head portion 70 which is threadably engaged with conduit section 42.
  • a barrel nozzle 72 Secured within the downstream end of sleeve 68Ii's a barrel nozzle 72 which is' provided with a central passageway 74 and a plurality of smaller passageways 76 located equidistantly from the longitudinalaxis of nozzle 72 and closely adjacent the wall 78 of conduit section 42.
  • the passageways 76 are angularly offset 45 from each other.
  • Means are provided for conjointly controlling the gate valve 36 and ball valve 64, said means comprising a stub arm 82 and a pivotal. connection with a stub shaft 88, the latter extending through a sleeve which is fixedly secured to plate valve' 36.
  • a sector plate 92 having an indicia bearing rim 94 is secured to conduit section 44.
  • Lever arm 82 is provided with a spring-pressed ball 96 adapted to be engaged with one or more depressions 98 formed in sector plate 92, said ball and depression means constituting click-stop in-. dicator means for arm 82.
  • passageway 66 is disposed transversely of the through passageway of conduit 32 and gate valve 36 is in closing relation with the discharge end of conduit 24.
  • ball valve 64 When arm 82 is in upright position relative to sector plate 92, ball valve 64 is partly open and gate valve 36 is closed.
  • the ball and gate valves When arm 82 is moved fully to the'left, with reference to FIG. 3, relative to sector plate 92, the ball and gate valves are both open.
  • the subject injector-mixer is especially adapted for th mixing and dispensing of slurries during forest fire control operations.
  • the solid material fed through conduit 24 may be, for example,'sodium-calcium borateor Bentonite clay.
  • the liquid material fed through conduit 32 is water, the normal operating pressure of which is about 100 pounds per square inch.
  • the formation of the slurry and its discharge from line 23 in a fire control operation may be intermittent in practice.
  • the ball and gate valve elements are moved to the position of FIG. 5.
  • the reduced flow of water through the ball valve washes the residual slurry out of conduit 32, thereby preventing any obstruction of conduit 32 by caking.
  • the barrel nozzle 72 provides a multi-jet water flow pattern beneath conduit 24 such that no spray or droplets of water passes above aperture 40 of conduit 32.
  • the outlet end of nozzle 72 is positioned adjacent the edge of aperure 40, and jet streams of uniform diameter for the distance required to traverse beneath aperture 40 are delivered from the nozzle passageways 74 and 76. These jet streams are slightly less in diameter than the diameters of said passageways Hand 76 from which they issue. The formation of such narrowed down jet streams is believed to contribute substantially to the end result desired and obtained, that is, the prevention of water from passing above aperture 40 of conduit 32.
  • a device .of the class described comprising a horizontally disposed first conduit having an inlet and an outlet end for fluid flow therethrough and having an opening formed in its upper wall, a vertically disposed second conduit mounted on said first conduit and having its lower discharge end disposed in spaced alignment with said opening of said first conduit, a horizontally disposed gate valve slidably positioned between the discharge end of said second conduit and said opening of said first conduit, an orifice ring removably disposed within the upper end of said second conduit to control the flow of solids through said second conduit into said first conduit, a ball valve positioned for rotational movement within the inlet end of saidfirst conduit, lever and link means for conjointly controlling said ball valve and said gate valve, and a nozzle, for controlling the'pattern of fluid flow past said opening, positioned within said first conduit between said ball valve and said opening in substantially immediately adjacent relation to said opening, said nozzle being cylindrical in form and having a plurality of How passageways thcrethrough disposed parallel to each other and to the longitudinal axis, of said
  • one of said nozzle passageways being disposed centrally of said nozzle, and the remainder of said passageways being disposedequidistantly from said one passageway and closely' adjacent the inner boundary wallof said first conduit.
  • a device of the class described comprising a horizontally disposed first conduit having an inlet and anoutlet end for fluid flow therethrough and having an opening formed in its upper wall, a vertically disposed second conduit mounted on said first conduit and having its lower discharge end disposed in spaced alignment with said opening of said first conduit, a horizontally disposed gate valve slidably positioned between the discharge end of said second conduit and said opening of said first conduit, a ball valve positioned for rotational movement within the inlet end of said first conduit, and lever and 1 link means for conjointly controlling said ball valve and said gate valve.

Description

April 20, 1965 R. sT. JOHN ORR 3,179,377
INJECTOR-MIXER, ESPECIALLY FOR FOREST FIRE CONTROL Filed Aug. 1, 1960 3 Sheets-Sheet 1 FIG../
I l 5 I6 I6 I x z\\ 30* 3o INVENTOR. [76.6 ROBERT $1" JOHN ORR Wu rad A TTORNEVS April 0, 1965 R. ST. JOHN ORR 3,179,377
. INJECTOR-MIXER, ESPECIALLY Foil FOREST FIRE CONTROL Filed Aug. 1; 1960 3 Sheets-Sheet 2 liH I INVENTOR. ROBERT 57: JOHN ORR A T TO/PNEVS R. ST. JOHN ORR April 20, 1965 3 Sheets-Sheet 3 Filed Au 1, 1960 IN V EN TOR.
ROBERT ST JOHN ORR m E b l Nv 3 9 p m m g 2. a mhm M? 1|. vw 8 mm wv v on m 6ft ATTORNEYS the mixing of solids andliquids to form slurries.
. discharge end of said second conduit.
United States Patent r 3,179,377 F INJECTGR-MIXER, ESPECIALLY FOR FOREST FIRE CONTROL Robert St. John 011', 69 Main St., San Francisco, Calif.
Filed Aug. 1,1960, Ser. No. 46,545 3 Claims. (CL 2591-4) This invention relates to'improvementsiin mixers which operate on the injector principle and which are useful in The improvements constituting the subject invention are particularly eflicient for the formation and dispensing under high pressure fluid flow conditions of fire retardant slurries for forest fire control. I
An object of the. invention is to provide, in a liquidsolid injector-mixer having. a horizontally'disposed first conduit'for fluid flow and a vertically disposed second conduit for solid flow intosaid first conduit, means for so controlling high pressure fluid flow through said first conduit that none. of said fluid will be received into the A further object of the invention is to provide, in a liquid-solid injector-mixer as above described, a fluid flow control nozzle immediately adjacent the juncture between said first and second conduits which is eifective to control the flow of fluidpastthe' inlet'of said second conduit so that no residual fluid will remain in the inlet end of said second conduit for commingling with'the solids therein prior to the entry of. said solids into said first conduit.
Still a furtherobject of the invention is to provide a liquid-solid injector-mixer as described embodying a control valve for each of said conduits and control means ineluding a single' control lever for conjointly operating said valves. 1
Other objects and advantages of the invention will be apparent from the following descripton taken in conjunction with the drawings forming part of this specification, and in which:
FIG. 1 is a general view in perspective of a complete system embodying the, improved injector-mixer of the invention;
FIG. 2 mixer of the assemblage system of FIG. 1;
FIG. 3 is a view in side elevation of the injector-mixer of FIG. 2; Y
FIG. 4 is a view in section taken along lines 44 of FIG. 2, but showing both the fluid and solid control valves in open position; I
FIG. 5 is a view partly in section and partly in side elevation showing the fluid control valve in 'a partially closed condition and the solid control valve in a fully closed condition;
FIG. 6 is a detail view in section taken along lines 66 of FIG. 4; and
FIG. 7 is a view in perspective of the fluid flow control.
nozzle of the injector-mixer.
The assemblage of FIG. 1 comprises a supporting framework 10 comprising top, bottom, and side support elements indicated, respectively, by 12, 14 and16, solids fed hopper 18, the injector-mixer secured to bottom support elements 14, a pressure gauge 22 whereby the fluid pressure within the injector-mixer 20' may be checked, and discharge line 23.
is an enlarged view in top plan of the injector- Hopper 18 is connected to the upper end of solids feed conduit 32 by the lower end of conduit 24 is a horizontal" gate valve 36 having feed-through orifice 38 adapted to be disposed in and out of registry with the discharge end of conduit 24 and with solids feed aperture 40 in conduit 32.
Conduit 32 (see FIG. 4) is comprised of multiple sections 42, 44 and*46 which are mutually secured in fluid sealed relationship by connectonmembers 48, 50 and sealing elements 52, 54 and '56. The inlet to pressure gauge 22 is shown at 57 in FIG. 4.
Rotatably'disposed between complemental semi-spherical surfaces 58 and 60, formed, respectively, on the in terior of conduit section .44 and insert member 62 for said conduit section, is a ball valve element 64 having a dia metral passageway 66 adapted, upon selective movement of said valve element 64, to be moved into and out of registry with the passageway of conduit 32. I Section 42 of conduit 32'is counter-bored'to receive a sleeve '68, said sleeve being provided with an enlarged head portion 70 which is threadably engaged with conduit section 42. Secured within the downstream end of sleeve 68Ii's a barrel nozzle 72 which is' provided with a central passageway 74 and a plurality of smaller passageways 76 located equidistantly from the longitudinalaxis of nozzle 72 and closely adjacent the wall 78 of conduit section 42.
The passageways 76 are angularly offset 45 from each other.
Means are provided for conjointly controlling the gate valve 36 and ball valve 64, said means comprising a stub arm 82 and a pivotal. connection with a stub shaft 88, the latter extending through a sleeve which is fixedly secured to plate valve' 36. i
A sector plate 92 having an indicia bearing rim 94 is secured to conduit section 44. Lever arm 82 is provided with a spring-pressed ball 96 adapted to be engaged with one or more depressions 98 formed in sector plate 92, said ball and depression means constituting click-stop in-. dicator means for arm 82.
When arm 82 is in the position shown in FIG. 3, the
passageway 66 is disposed transversely of the through passageway of conduit 32 and gate valve 36 is in closing relation with the discharge end of conduit 24. When arm 82 is in upright position relative to sector plate 92, ball valve 64 is partly open and gate valve 36 is closed. When arm 82 is moved fully to the'left, with reference to FIG. 3, relative to sector plate 92, the ball and gate valves are both open. The subject injector-mixer is especially adapted for th mixing and dispensing of slurries during forest fire control operations. The solid material fed through conduit 24 may be, for example,'sodium-calcium borateor Bentonite clay. The liquid material fed through conduit 32 is water, the normal operating pressure of which is about 100 pounds per square inch.
The formation of the slurry and its discharge from line 23 in a fire control operation may be intermittent in practice. When it is desired to discontinue slurry formation for the time being, the ball and gate valve elements are moved to the position of FIG. 5. The reduced flow of water through the ball valve washes the residual slurry out of conduit 32, thereby preventing any obstruction of conduit 32 by caking.
When both valves are open, as in FIG. 4, and the slurry is being formed under the water pressure condition above-mentioned it is very important that no water enter even the lowest portion of conduit 24 to wet the interior surface. thereof. If this were to happen and temporary shutdown of the injector-mixer were to follow, the solids which would thereafter accumulate within conduit 24,
Patented Apr. 20, 1965 beneath orifice ring 26 and above the closed gate valve 36, would become wetted. Since the above-mentioned solid materials are very prone to caking, a degree of caking within conduit could occur sufficient to prevent proper feed of the solids upon resumption of operation, thereby rendering the equipment inefiective until the blockage condition is cured. The possibility of a down time situation like this cannot be chanced in a forest fire control operation.
The barrel nozzle 72 provides a multi-jet water flow pattern beneath conduit 24 such that no spray or droplets of water passes above aperture 40 of conduit 32.. The outlet end of nozzle 72 is positioned adjacent the edge of aperure 40, and jet streams of uniform diameter for the distance required to traverse beneath aperture 40 are delivered from the nozzle passageways 74 and 76. These jet streams are slightly less in diameter than the diameters of said passageways Hand 76 from which they issue. The formation of such narrowed down jet streams is believed to contribute substantially to the end result desired and obtained, that is, the prevention of water from passing above aperture 40 of conduit 32.
What I claim as new and desire to secure by Letters Patent is: I g
1. A device .of the class described comprising a horizontally disposed first conduit having an inlet and an outlet end for fluid flow therethrough and having an opening formed in its upper wall, a vertically disposed second conduit mounted on said first conduit and having its lower discharge end disposed in spaced alignment with said opening of said first conduit, a horizontally disposed gate valve slidably positioned between the discharge end of said second conduit and said opening of said first conduit, an orifice ring removably disposed within the upper end of said second conduit to control the flow of solids through said second conduit into said first conduit, a ball valve positioned for rotational movement within the inlet end of saidfirst conduit, lever and link means for conjointly controlling said ball valve and said gate valve, and a nozzle, for controlling the'pattern of fluid flow past said opening, positioned within said first conduit between said ball valve and said opening in substantially immediately adjacent relation to said opening, said nozzle being cylindrical in form and having a plurality of How passageways thcrethrough disposed parallel to each other and to the longitudinal axis, of said first conduit. 7
2. The device of claim 1, one of said nozzle passageways being disposed centrally of said nozzle, and the remainder of said passageways being disposedequidistantly from said one passageway and closely' adjacent the inner boundary wallof said first conduit.
3. A device of the class described comprising a horizontally disposed first conduit having an inlet and anoutlet end for fluid flow therethrough and having an opening formed in its upper wall, a vertically disposed second conduit mounted on said first conduit and having its lower discharge end disposed in spaced alignment with said opening of said first conduit, a horizontally disposed gate valve slidably positioned between the discharge end of said second conduit and said opening of said first conduit, a ball valve positioned for rotational movement within the inlet end of said first conduit, and lever and 1 link means for conjointly controlling said ball valve and said gate valve.
1 References Cited by the Examiner UNITED STATES PATENTS j1,6i4,770 1/27 Aylin g'; 302 25 1,734,164 11/29] Faber 16915 7 FOREIGN PATENTS 61,613 12/54 France.
(Addition to No, 940,775
I WALTER A. SCHEEL, Primary Examiner.

Claims (1)

  1. 3. A DEVICE OF THE CLASS DESCRIBED COMPRISING A HORIZONTALLY DISPOSED FIRST CONDUIT HAVING AN INLET AND AN OUTLET END FOR FLUID FLOW THERETHROUGH AND HAVING AN OPENING FORMED IN ITS UPPER WALL, A VERTICALLY DISPOSED SECOND CONDUIT MOUNTED ON SAID FIRST CONDUIT AND HAVING ITS LOWER DISCHARGE END DISPOSED IN SPACED ALIGNMENT WITH SAID OPENING OF SAID FIRST CONDUIT, A HORIZONTALLY DISPOSED GATE VALVE SLIDABLY POSITIONED BETWEEN THE DISCHARGE END OF SAID SECOND CONDUIT AND SAID OPENING OF SAID FIRST CONDUIT, A BALL VALVE POSITIONED FOR ROTATIONAL MOVEMENT WITHIN THE INLET END OF SAID FIRST CONDUIT, AND LEVER AND
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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2350665A1 (en) * 1972-10-10 1974-04-25 Monsanto Co TRANSPORTABLE ARRANGEMENT FOR MAKING SUSPENSIONS AND SOLUTIONS
US4238076A (en) * 1978-02-22 1980-12-09 Veitscher Magnesitwerke-Actien-Gesellschaft Apparatus for building up and repairing the refractory lining of industrial furnaces and hot-running vessels
EP2446933A3 (en) * 2010-10-06 2013-06-05 bedeko GmbH Method for extinguishing fires in buildings and facilities

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1614770A (en) * 1923-02-02 1927-01-18 United Conveyor Corp Conveyer fitting
US1734164A (en) * 1927-03-02 1929-11-05 Nat Foam System Inc Means for producing fire-extinguishing foam
FR940775A (en) * 1947-02-07 1948-12-22 Improvements to devices for braking or accelerating the flow of fluids
FR61613E (en) * 1947-02-07 1955-05-16 Improvements to devices for braking or accelerating the flow of fluids

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1614770A (en) * 1923-02-02 1927-01-18 United Conveyor Corp Conveyer fitting
US1734164A (en) * 1927-03-02 1929-11-05 Nat Foam System Inc Means for producing fire-extinguishing foam
FR940775A (en) * 1947-02-07 1948-12-22 Improvements to devices for braking or accelerating the flow of fluids
FR61613E (en) * 1947-02-07 1955-05-16 Improvements to devices for braking or accelerating the flow of fluids

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2350665A1 (en) * 1972-10-10 1974-04-25 Monsanto Co TRANSPORTABLE ARRANGEMENT FOR MAKING SUSPENSIONS AND SOLUTIONS
US4238076A (en) * 1978-02-22 1980-12-09 Veitscher Magnesitwerke-Actien-Gesellschaft Apparatus for building up and repairing the refractory lining of industrial furnaces and hot-running vessels
EP2446933A3 (en) * 2010-10-06 2013-06-05 bedeko GmbH Method for extinguishing fires in buildings and facilities

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