US3387329A - Processing apparatus for gasgenerating compositions - Google Patents

Processing apparatus for gasgenerating compositions Download PDF

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Publication number
US3387329A
US3387329A US646772A US64677267A US3387329A US 3387329 A US3387329 A US 3387329A US 646772 A US646772 A US 646772A US 64677267 A US64677267 A US 64677267A US 3387329 A US3387329 A US 3387329A
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United States
Prior art keywords
alignment means
elongated
propellant
alignment
matrix
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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 - Lifetime
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US646772A
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English (en)
Inventor
John N Godfrey
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Susquehanna Corp
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Susquehanna Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from US498780A external-priority patent/US3359350A/en
Priority to IL26660A priority Critical patent/IL26660A/en
Priority to GB45966/66A priority patent/GB1156994A/en
Priority to NL6614460A priority patent/NL6614460A/xx
Priority to NO165220A priority patent/NO115989B/no
Priority to FR80747A priority patent/FR1526908A/fr
Priority to DE19661496702 priority patent/DE1496702A1/de
Priority to DK543666AA priority patent/DK117395B/da
Application filed by Susquehanna Corp filed Critical Susquehanna Corp
Priority to US646772A priority patent/US3387329A/en
Priority to BE705369D priority patent/BE705369A/xx
Publication of US3387329A publication Critical patent/US3387329A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
    • B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
    • B29C70/06—Fibrous reinforcements only
    • B29C70/10—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres
    • B29C70/12—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres using fibres of short length, e.g. in the form of a mat
    • B29C70/14—Fibrous reinforcements only characterised by the structure of fibrous reinforcements, e.g. hollow fibres using fibres of short length, e.g. in the form of a mat oriented
    • C—CHEMISTRY; METALLURGY
    • C06—EXPLOSIVES; MATCHES
    • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
    • C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
    • C06B21/0033—Shaping the mixture
    • C—CHEMISTRY; METALLURGY
    • C06—EXPLOSIVES; MATCHES
    • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
    • C06B21/00—Apparatus or methods for working-up explosives, e.g. forming, cutting, drying
    • C06B21/0033—Shaping the mixture
    • C06B21/0075—Shaping the mixture by extrusion
    • C—CHEMISTRY; METALLURGY
    • C06—EXPLOSIVES; MATCHES
    • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
    • C06B45/00—Compositions or products which are defined by structure or arrangement of component of product
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02K—JET-PROPULSION PLANTS
    • F02K9/00—Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof
    • F02K9/08—Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof using solid propellants
    • F02K9/24—Charging rocket engines with solid propellants; Methods or apparatus specially adapted for working solid propellant charges
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02K—JET-PROPULSION PLANTS
    • F02K9/00—Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof
    • F02K9/08—Rocket-engine plants, i.e. plants carrying both fuel and oxidant therefor; Control thereof using solid propellants
    • F02K9/26—Burning control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B1/00—Explosive charges characterised by form or shape but not dependent on shape of container
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2705/00—Use of metals, their alloys or their compounds, for preformed parts, e.g. for inserts

Definitions

  • This invention relates to methods and apparatus for aligning elongated metallic heat conductors within a viscous propellant matrix and for making solid propellant grains containing discontinuous, elongated metallic heat conductors longitudinally aligned in the direction of flame propagation of the grain.
  • the maximum increase in propellant burning rate is obtained when the elongated metallic heat conductors are longitudinally aligned in the direction of flame propagation of the grain.
  • Discontinuous, short, elongated metallic heat conductors can be economically incorporated into propellant compositions by conventional mixing techniques. Discontinuous heat conductors thus incorporated are, however, disposed in irregular orientation within the propellant grain and maximum burning rates are not obtained. Furthermore, variations in orientation of the discontinuous conductors throughout the length of the grain often result in non-uniform linear burning rates.
  • FIGURE 1 is an illustration, partly broken away, of an apparatus for aligning elongated, discontinuous, metallic heat conductors.
  • FIGURE 2 is a longitudinal sectional view of the apparatus shown in FIGURE 1 wherein the orientation of particles according to this invention is schematically illustrated.
  • FIGURE 3 is an illustration, partly broken away, of an alignment apparatus employing alternate embodiments of alignment means.
  • FIGURES 4, 5, 6, and 7 are longitudinal views, partly in section illustrating the production of inhibited propellant grains according to this invention.
  • FIGURE 1 illustrates an apparatus utilized in the practice of the invention. The use of this apparatus is illustrated in FIGURE 2 wherein a viscous propellant matrix 5 containing short wire heat conductors 6 is forced through containment means comprising a passageway 1 which is serially transversed along its length by alignment means 2, 3, and 4 each comprising parallel elongated members 2a, 3a, and 4a respectively. It is seen that the wires in the matrix are disposed in random distribution above alignment means 2 and become progressively longitudinally aligned in a direction more nearly parallel to the longitudinal axis as they pass successive alignment means.
  • Alignment of the Wires is accomplished by contact with the elongated members of the alignment means and/or by laminar fiow patterns induced in the matrix by the'elongated members.
  • the force of the moving matrix turns the wire about the point of contact into a direction more nearly parallel to the longitudinal axis of the passageway.
  • the alignment means induces regions of laminar flow even in highly viscous compositions that would normally approach plug flow patterns.
  • each alignment means defines channels in the passagewav and that the boundaries of the channels defined by different alignment means are not longitudinally colinear. That is, longitudinal planes subtending the different alignment means are laterally and/or angularly displaced from each other.
  • the elongated members 3a are positioned to be cont-acted by wires which did not contact elongated members 2a.
  • the elongated members 3a induce additional regions of laminar flow to effect alignment of wires which do not actually contact the elongated members-In addition, wires already partially aligned by preceding alignment means are further aligned intoa direction more nearly parallel to the longitudinal axis of the passageway by the successive alignment means.
  • the containment means can be, for example, a passageway as described above or a stationary container such as a propellant grain mold or inhibitor beaker in which the alignment means is movable relative to the walls of the mold or beaker and any matrix disposed therein.
  • the containment means can be of any desired cross-sectional design. The cross-sectional dimensions preferably are substantially uniform along the length of the containment means wherein the alignment means are disposed so that areas of stagnation are not induced in the flowing propellant matrix.
  • the alignment means of this invention are transverse to the longitudinal axis of the containment means and define channels through which the matrix passes or which are passed through the matrix. It is necessary that the channels have a transverse dimension at least equal to the longest distance subtending any heat conductor adjacent to the alignment means in order to prevent entrapment of the heat conductors and channel obstruction or blocking. To effect additional alignment by additional alignment means it is necessary that the boundaries of channels defined by the additional alignment means not be longitudinally colinear with the boundaries of channels defined by previous alignment means through which the matrix is moved.
  • the alignment means of this invention preferably comprise at least one elongated member transversing the longitudinal axis of the containment means.
  • Elongated members of alignment means may be arranged in a variety of patterns.
  • the elongated members in each alignment means may be arranged in a substantially parallel non-intersecting relationship as illustrated in FIGURE 1.
  • alignment means 7 consists of an elongated memher 7:: in the form of a spiral and alignment means 8 is formed by elongated members 8a arranged in the form of a screen.
  • Other arrangements of elongated mem bers to form alignment means within the spirit of this invention will be readily apparent.
  • the elongated members will be relatively narrow in order to prevent stagnation of propellant flow.
  • elongated wires or strips are excellently suited for use as components of alignment means.
  • the matrix is very viscous and additional strength is required of the elongated members of alignment means; thin elongated bands having their widths orientated substantially parallel to the longitudinal axis of the containment means may be advantageously utilized.
  • the elongated members of different alignment means are caused to define different channels in the containment means by varying the spacing or arrangement of elongated members of different alignment means or by directing the members of different means across the containment means at varying radial angles.
  • alignment means comprising elongated members arranged in non-intersecting relationship as shown in FIGURE 1 minimizes blocking problems since there are no corners to trap the heat conductors. Such an arrangement is, therefore, particularly preferred.
  • propellant grains be provided with inhibitor casings in order to restrict the burning of the propellant grain to desired surfaces.
  • FIGURE 4 An inhibitor casing 9, attached to a heat plate It is positioned around a longitudinal passageway 1 containing alignment means. As the propellant matrix is forced through the passageway and alignment means, the inhibitor casing 9 and head plate 10 are simultaneously displaced with respect to the alignment means and passageway to the position indicated by dotted line 11. The displacement is effected at about the rate at which the propellant matrix enters the inhibitor casing. Thus, there is substantially no relative motion between the inhibitor casing and the propellant matrix which would serve to disorient the aligned staples.
  • the matrix is cured or hardened within the encasement in such a manner as to effect an intimate bond between the hardened propellant grain and the inhibitor casing. This generally can be accomplished by curing the matrix within the insulating encasement under pressure.
  • the insulating encasement 9b can be displaced into the position indicated by dotted line 14 into a stationary mold 12a as shown in FIGURE 6.
  • the inhibitor casing is formed of flexible material, the inhibitor casing may be inverted over a mold 1212 as shown in FIGURE 7. When the propellant matrix is forced into the inhibitor casing 90 the casing will be reinverted and forced into the position shown by dotted line 15.
  • the inhibitor casing may be formed of natural or synthetic polymers which may, if desired, be reinforced with fibers, wires, fabrics or the like.
  • a wide variety of inhibitor casings and materials and methods suitable for making the same are Well-known in the propellant art, and accordingly, no attempt will be made to give a detailed discussion of inhibitor casings in this application.
  • a particularly preferred propellant grain made according to this invention utilizes a combustion-restricting casing such as disclosed in Alvist V. Rice, Myron G. De- Fries and Roland C. Webster, United States patent appl cation Ser. No. 370,954, filed May 28, 1964, and copending herewith.
  • the inhibitor casing described therein comprises an inhibitor sleeve formed of elastic material.
  • the sleeve has restraining means embedded therein to provide a preferential direction of elasticity of the sleeve.
  • the sleeve is restrained so as to inhibit stretch in the longitudinal direction While permitting relatively free stretch in the radial direction of the sleeve.
  • Such an inhibitor casing having an internal dimension equal to that of the internal dimension of the passageway can be stretched over a passageway as in FIGURES 5 and 6, or a mold as in FIGURE 7; and its elastic properties will return it to an internal dimension substantially the same as the internal dimension of the passageway when the loading process forces the encasement from the passageway or mold.
  • relative motion between the propellant matrix and the inhibitor casing is further minimized.
  • hardening a propellant matrix contained within such an inhibitor casing in a grain mold under pressure expands the casing to conform to the mold thereby providing a propellant grain whose dimensions are as accurate as those of the mold.
  • the elongated heat conductors can be made of any heat conducting material suitable for eifecting improved performance of gas-generating compositions.
  • staples e.g. thin flat metal strips, or short wires of aluminum, magnesium, beryllium, zirconium, titanium, silver, copper or alloys thereof can be effectively employed.
  • such conductors can be coated with a self-oxidant composition having a higher burning rate than the gasgenerating matrix to provide gas-generating compositions having even higher burning rates than are obtainable with uncoated conductors.
  • the conductors can be coated with non-self-oxidant compositions having substantially lower heat conductivity than the elongated conductors to provide gas-generating compositions having burning rates intermediate the rate of a non-conductor containing composition and a composition containing uncoated conductors.
  • coated and uncoated heat conductors are found in aforementioned United States Patent Nos. 3,116,692; 3,109,374; 3,109,- 375; and United States patent application Ser. No. 337,- 955 filed Jan. 15, 1964, and copending herewith.
  • the size of the heat conductors is determined by consideration of desired performance characteristics of the propellant.
  • the maximum length of the heat conductors is limited only by the size of the passageway and by techniques of mixing conductors into the matrix. Generally, the conductor length should be no greater than one-half the internal diameter of the passageway. Since breakage of longer conductors may occur during mixing, a conductor length of less than 2 inches is preferred and a length of /2 inch or less is particularly preferred.
  • Example 1 A viscous propellant matrix having the following composition was prepared:
  • Burning rate catalyst 2 Ammonium perchlorate Aluminum powder Elongated aluminum heat conductors (average size .05 in. .002 in. .0008 in.)
  • Burning rate of strand cut Burning rate of strand cut; p.s.i.a. in orientation direction, in arm-orientation direcin.lsec. tion, in./sec.
  • Example 2 A propellant mix having approximately the following formulation was prepared:
  • the apparatus of this invention has been described and exemplified for use in orientation of elongated heat conductors in gas-generating compositions in view of its particular advantages in this "application.
  • the apparatus is inherently suited for orienting of elongated particles in any viscous matrix to provide, for example, product-s having improved strength, appearance, or conductivity.
  • An apparatus for aligning elongated metallic heat conductors within a viscous, combustible, gas-generating matrix comprising in combination a passageway having a plurality of alignment means serially disposed therein transversely to the longitudinal axis thereof, each of said alignment means being spaced from other alignment means along the longitudinal axis of said passageway, each of said alignment means comprising a plurality of substantially parallel elongated members, said members being separated by a distance sufiicient to permit passage of said heat conductors, and the elongated members of each of said alignment means being radially angul'arly displaced from the elongated members of other of said alignment means thereby defining channels in said passageway having boundaries not longitudinally colinear with the boundaries of channels defined by other alignment means.
  • An apparatus for aligning elongated particles within a viscous matrix comprising in combination a passageway having a plurality of alignment means serially disposed therein trnsversely to the longitudinal axis thereof, each of said alignment mean-s being spaced from other alignment means along the longitudinal axis of said passageway, each of said alignment means comprising a plurality of substantially parallel elongated members, said members being separated by a distance'sufficient to permit passage of said elongated particles, and the elongated members of each of said alignment means being radially angularly displaced from the elongated members of other of said alignment means thereby defining channels in said passageway having boundaries not longitudinally coline'ar with the boundaries of channels defined by other alignment means.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Organic Chemistry (AREA)
  • Combustion & Propulsion (AREA)
  • Composite Materials (AREA)
  • Textile Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Insulating Bodies (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Feeding And Controlling Fuel (AREA)
  • Feeding, Discharge, Calcimining, Fusing, And Gas-Generation Devices (AREA)
  • Air Bags (AREA)
US646772A 1965-10-20 1967-03-09 Processing apparatus for gasgenerating compositions Expired - Lifetime US3387329A (en)

Priority Applications (9)

Application Number Priority Date Filing Date Title
IL26660A IL26660A (en) 1965-10-20 1966-10-09 Method and device for processing repellent mixtures that form gas
GB45966/66A GB1156994A (en) 1965-10-20 1966-10-14 Processing method and apparatus for Gas Generating Compositions
NL6614460A NL6614460A (forum.php) 1965-10-20 1966-10-14
NO165220A NO115989B (forum.php) 1965-10-20 1966-10-19
FR80747A FR1526908A (fr) 1965-10-20 1966-10-20 Procédé et appareil pour la fabrication d'éléments générateurs de gaz de propulsion
DE19661496702 DE1496702A1 (de) 1965-10-20 1966-10-20 Verfahren und Vorrichtungen zur Ausrichtung von Waermeleitern innerhalb einer Treibmittelmasse und zur Herstellung von Feststoff-Treibsaetzen aus ?eser
DK543666AA DK117395B (da) 1965-10-20 1966-10-20 Fremgangsmåde til ensretning af langstrakte, metalliske varmeledere, der er tilfældigt fordelt i en viskos, brændbar masse, og apparat til udøvelse af fremgangsmåden.
US646772A US3387329A (en) 1965-10-20 1967-03-09 Processing apparatus for gasgenerating compositions
BE705369D BE705369A (forum.php) 1965-10-20 1967-10-19

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US498780A US3359350A (en) 1965-10-20 1965-10-20 Method of aligning elongated metallic heat conductors within a viscous, gasgenerating matrix
US646772A US3387329A (en) 1965-10-20 1967-03-09 Processing apparatus for gasgenerating compositions

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US3387329A true US3387329A (en) 1968-06-11

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US646772A Expired - Lifetime US3387329A (en) 1965-10-20 1967-03-09 Processing apparatus for gasgenerating compositions

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US (1) US3387329A (forum.php)
DE (1) DE1496702A1 (forum.php)
DK (1) DK117395B (forum.php)
GB (1) GB1156994A (forum.php)
IL (1) IL26660A (forum.php)
NL (1) NL6614460A (forum.php)
NO (1) NO115989B (forum.php)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10385806B2 (en) * 2015-10-02 2019-08-20 The United States Of America As Represented By The Secretary Of The Army Solid propellant grain

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0587900A4 (en) * 1992-02-10 1995-09-27 Daicel Chem Linear gas generating agent and filter construction for gas generator

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1245898A (en) * 1916-07-25 1917-11-06 Revere Rubber Co Die for tire-tubing machines.
US2242364A (en) * 1938-06-18 1941-05-20 Montanari Cesare Machine for manufacturing macaroni automatically
DE873140C (de) * 1940-10-10 1953-04-09 Siemens Ag Vorrichtung zum Spritzen von Formkoerpern aus waermebildsamen Massen, insbesondere Kunstharzen
US2682081A (en) * 1951-02-28 1954-06-29 Richard A Fisch Method of producing a striated extruded tubing
FR1127140A (fr) * 1955-05-26 1956-12-10 Appareil de boudinage du savon
US2779972A (en) * 1952-09-10 1957-02-05 Kins Georg Heinrich Pressure vessel
US3344215A (en) * 1962-10-03 1967-09-26 Shell Oil Co Production of expanded thermoplastic product

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1245898A (en) * 1916-07-25 1917-11-06 Revere Rubber Co Die for tire-tubing machines.
US2242364A (en) * 1938-06-18 1941-05-20 Montanari Cesare Machine for manufacturing macaroni automatically
DE873140C (de) * 1940-10-10 1953-04-09 Siemens Ag Vorrichtung zum Spritzen von Formkoerpern aus waermebildsamen Massen, insbesondere Kunstharzen
US2682081A (en) * 1951-02-28 1954-06-29 Richard A Fisch Method of producing a striated extruded tubing
US2779972A (en) * 1952-09-10 1957-02-05 Kins Georg Heinrich Pressure vessel
FR1127140A (fr) * 1955-05-26 1956-12-10 Appareil de boudinage du savon
US3344215A (en) * 1962-10-03 1967-09-26 Shell Oil Co Production of expanded thermoplastic product

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10385806B2 (en) * 2015-10-02 2019-08-20 The United States Of America As Represented By The Secretary Of The Army Solid propellant grain

Also Published As

Publication number Publication date
NO115989B (forum.php) 1969-01-06
NL6614460A (forum.php) 1967-04-21
GB1156994A (en) 1969-07-02
DE1496702A1 (de) 1969-07-03
IL26660A (en) 1970-06-17
DK117395B (da) 1970-04-20

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