US3053727A - Mounting for electrical resistance elements and method for preparing the same - Google Patents

Mounting for electrical resistance elements and method for preparing the same Download PDF

Info

Publication number
US3053727A
US3053727A US62140A US6214060A US3053727A US 3053727 A US3053727 A US 3053727A US 62140 A US62140 A US 62140A US 6214060 A US6214060 A US 6214060A US 3053727 A US3053727 A US 3053727A
Authority
US
United States
Prior art keywords
millboard
weight
mounting
approximately
acid phosphate
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 - Lifetime
Application number
US62140A
Other languages
English (en)
Inventor
George J Adomshick
Robert G Quinn
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.)
QUIN-T Corp A CORP OF DE
Johns Manville Corp
Johns Manville
Original Assignee
Johns Manville
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
Application filed by Johns Manville filed Critical Johns Manville
Priority to US62140A priority Critical patent/US3053727A/en
Priority to GB33623/61A priority patent/GB943864A/en
Priority to BE608953A priority patent/BE608953A/fr
Application granted granted Critical
Publication of US3053727A publication Critical patent/US3053727A/en
Anticipated expiration legal-status Critical
Assigned to QUIN-T CORPORATION, A CORP. OF DE. reassignment QUIN-T CORPORATION, A CORP. OF DE. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: STATE STREET BANK AND TRUST COMPANY
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/02—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances
    • H01B3/06—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of inorganic substances asbestos
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
    • C04B28/24—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing alkyl, ammonium or metal silicates; containing silica sols
    • C04B28/26—Silicates of the alkali metals
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L59/00—Thermal insulation in general
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/10—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor
    • H05B3/16—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor the conductor being mounted on an insulating base
    • C—CHEMISTRY; METALLURGY
    • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
    • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
    • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
    • C04B2111/30—Nailable or sawable materials

Definitions

  • This invention relates to a substitute material or product for mica or ceramic components which is useful in and about electrical devices. More particularly the invention comprises a novel and improved product for the fabrication of mountings, supports or the like for electrical resistance heating elements, and the method of producing the same.
  • Asbestos millboard, and various compositions or products based upon or comprising asbestos millboard have heretofore been proposed and utilized in the manufacture of mountings or supports for electrical resistance elements, and some have been so employed with varying degrees of success.
  • One type of improved asbestos millboard support for high resistance electrical conductors for example, is illustrated by United States Letters Patent No. 2,541,273.
  • the asbestos millboard mounting or support products now available for electrical appliance and the like nevertheless, have not been extensively adapted or utilized by manufacturers of electrical devices or appliances because of their generally poor electrical properties and/ or lack of strength, among other disadvantages.
  • Another object of this invention is to provide an asbestos millboard product or composition which exhibits improved and adequate electrical insulating properties throughout all humidity conditions over extended periods of time and which is completely resistant to the temperature conditions encountered in electrical heating devices or mechanisms such as irons, toasters, heaters, etc.
  • An additional object of this invention is to provide mounting or support means for electrical resistance heating elements or wires and a method of producing the same, which will resist warping or deformation and will maintain their rigidity, coherency, dimensional stability,
  • portions generally comprise the means for supporting, securing and retaining the wires comprising the heating ele ents and accordingly consist of a critical portion or area which is subjected to the greatest stress and severest temperature conditions.
  • a still further object of this invention is to provide a method or means for producing an inexpensive asbestos millboard product or composition which has greater strength and electrical insulating properties than have heretofore been available in such products for use as a mounting or support for electrical resistance heating elements.
  • FIG. 1 is a plane view illustrating a typical millboard mounting for toaster heating elements showing the serrated edge portions comprising a series of cut-out forming projections or nibs;
  • FIG. 2 is a cross-sectional view taken on line 2-2 of FIG. 1.
  • the porous asbestos millboard which has been determined to be effectively receptive to the indurating procedure or treatment briefly comprises a medium density board composed of asbestos fiber, a relatively high proportion of diatomaceous earth, and, as a binder, a dry, activated in situ, alkali metal silicate consisting of sodium and/or potassium silicate.
  • the indurating procedure which has been found to effectively complement the asbestos millboard of this invention comprises the application of an aluminum acid phosphate impregnant coupled with a unique means of curing the same.
  • porous millboard comprising the foregoing components, upon substantially complete solubilization or activation of the dry alkali metal silicate binder may be cut, punched or otherwise reduced to its ultimate size and/or configuration for an electrical resistance mounting or support prior to the indurating treatment comprising the aqueous aluminum acid phosphate solution impregnation or in accordance with the more preferred procedure, the board is initially impregnated with the indurating aluminum acid phosphate solution and subsequently cut, punched or the like to obtain a mounting or support of the ultimate configuration and/or size desired while still wet or containing the absorbed aluminum acid phosphate solution.
  • the sequence or order of rendering the board to the ultimate size and configuration of the intended product and of applying the indurating impregnation is not critical provided that the cutting or shaping of the millboard mount or support to its ultimate physical form or configuration is completed before removal or loss of a substantial amount of the absorbed aqueous aluminum acid phosphate impregnating solution.
  • the two major surfaces, i.e., the front and back sides, of the board or mounting formed therefrom are blanketed or covered with a substantially water-impervious material such as a plastic sheet to bar or impede egress or escape of the water content of the impregnating solution from either of said major surfaces and to direct and confine migration of the aqueous solution to the marginal or peripheral edge portion(s) of the shaped mounting or support whereby the escape of the water content therefrom results in an accumulation or higher concentration of the solution solute in and about said marginal or peripheral edge portion(s) of the mounting and in turn further increases the beneficial effects of the impregnant in the critical portions of the object.
  • a substantially water-impervious material such as a plastic sheet to bar or impede egress or escape of the water content of the impregnating solution from either of said major surfaces and to direct and confine migration of the aqueous solution to the marginal or peripheral edge portion(s) of the shaped mounting or support whereby the escape of the water content therefrom results in an accumulation or higher
  • Asbestos millboard electrical resistance element or wire mountings or supports typically consist of sheets of more or less conventional types of inorganic millboard products which are cut or otherwise shaped to a general configuration suitably adaptable for installation in the particular electrical device or appliance contemplated.
  • the peripheral edge portion(s), or segments thereof, of the shaped mount or support of the usual sheet construction is provided with some means of supporting and retaining or securing the electrical resistance heating elements or wires, or coils composed of the same, which generally consist simply of a multiplicity of marginal perforations or a series of edge cuts or notches forming a serrated or scalloped border area of alternating slots and projections or nibs through or in which the wire or like component may be threaded and securely retained.
  • 1 of the drawing comprises a typical design or configuration of an asbestos millboard sheet mounting or support for an electric toaster resistance wire heating element illustrating a conventional serrated border or peripheral edge portion(s) configuration which provides effective retaining and spacing means for resistance wires or elements and conveniently ready access in stringing or winding the same.
  • the marginal or peripheral edge and corners or ends of a product of an object composed of a frangible material such as a sheet of asbestos millboard naturally comprise an area(s) of maximum stress and in turn breakage, and such a precarious condition or susceptibility is obviously further aggravated or intensified by the cutting of perforations, slots or the like and removal of a portion of the material from this area, and subsequent installation of wires, etc., handling, and repeated exposure to the high temperatures of the wires comprising the heating elements.
  • this invention In addition to providing an asbestos millboard composition or product of sufiicient strength and electrical properties to replace and surpass previous conventional materials, this invention also embodies or provides for the reinforcement of the critical marginal edge or corner portions of the millboard article by concentrating the effects thereof or characteristics imparted thereby, such as structural strength, resistance to heat, breakage and deformation, and dielectric properties, within and about said portions or areas.
  • the reinforcing effect of this invention is produced by a concentration or accumulation of the aluminum acid phosphate indurating solution solute in the portions or areas most suspectible to damage, breakage and deterioration or the like.
  • FIG. 2 cross-sectional view of the object of FIG. 1 visually illustrates the concentration of the aluminum acid phosphate indurating solution solute or reaction product(s) thereof in and about the edge(s) portions of the millboard mount.
  • the asbestos millboard component of this invention should comprise approximately 40-60% by weight of asbestos fiber, approximately 35-45% by weight of diatomaceous earth, and approximately 7.5-12.5% by weight of dry sodium and/or potassium silicate, preferably consisting of about 50% by weight of asbestos fiber, about 40% by weight of diatomaceous earth, and about 10% by Weight of dry sodium silicate, and may be prepared or formed from any typical source or grade of the specified components commonly utilized in the manufacture of millboard. It has been determined, however, that the use of a relatively short grade asbestos fiber in the board will further enhance both the strength and electrical properties of the final product.
  • a suitable and preferred grade of asbestos fiber comprises one having approximately the following McNett analysis stated as the weight percent passing through a standard mesh screen:
  • Formation of the millboard can be effected on a wet machine or in any conventional manner, but activation or solubilization of the relatively insoluble dry alkali metal silicate binder requires substantial periods of exposure to elevated temperature and moisture conditions, such, for example, as temperature in the vicinity of approximately 200 to 400 F., preferably about 300 F., and high moisture conditions ranging from about to 100% relative humidity for periods of approximately 4 to 8 hours.
  • the indurating impregnant an aqueous solution of aluminum acid phosphate, is prepared by combining hydrated alumina (Al O .H O) with phosphoric acid (H PO in a mol ratio of, for example, about 1.4/3.0 of hydrated alumina to phosphoric acid.
  • H PO phosphoric acid
  • the products thereof should be diluted to produce a readily handleable solution for the subsequent impregnation, typically about a 25% solution concentration.
  • 'Induration of the millboard may be carried out by any convenient or suitable impregnating procedure, viz., dipping or submerging, spraying, brushing, coating, etc., but should be carried to the point wherein the millboard retains 15 to 50% by weight of the aluminum acid phosphate solute, preferably approximately 30% of solute by weight of the board.
  • the aluminum acid phosphate indurant, or a component or components thereof reacts with the millboard or the asbestos constituent thereof to result in a hard, lntegrated product(s) of outstanding strength and electrical properties.
  • Asbestos fiber (Grade 5K) 1, 000 50 Diatomaceous earth 800 40 Dry silicate of soda 200 Table 1 PHYSICAL PROPERTIES OF UNTREA'IED MILLBOARD [Avg of 12 samples-cross section of entire run] 4 .6. 10.62163 lb./sq. in.
  • An indurating impregnant for the millboard was prepared by combining 55.3 lbs. of 85% phosphoric acid (H PO with 17.3 lbs. of hydrated alumina (Alcoa C-31) and upon allowing the reaction to go to substantial completion, adding suflicient water, in this case 134 lbs, to produce a 25% solids solution.
  • the millboard cut into strips 5 m" x 48" for convenience in handling and subsequent processing and saturated with a 25% solids aluminum acid phosphate solution by pouring this solution on a strip ahead of a small hand operated wringer and duplicating the procedure for the other side whereby a solution pick-up was obtained of approximately 17-18% solution solids based upon the weight of the millboard and the solids of the solution.
  • the treated millboard strips were divided into two equal groups and half were first dried at 170-180 F. for approximately 20 hours and then toaster mounts were die punched from the dry millboard strips in the configuration illustrated in FIG. 1. From the other half of the impregnated millboard strips, toaster elements of an identical configuration were die punched while the millboard was still wet with and containing the absorbed aluminum acid phosphate solution.
  • the wet punched mounts were PHYSICAL PROPERTIES OF TREATED MILLBOARD [Avg of 10 samples (18% phosphate solids pick-upbased ontnoiimal wt. of board). Weighed immediately after satura 10H Weight (lo/sq. ft.) Caliper mils) Density (lb/cu. ft; MD tensile (lb/in. 54D tensile (1b./in.)
  • Density (lb/cu. ft.) 41 MD tensile (p.s.i.) 457 CD tensile (p.s.i.) 276 was saturated by submersion in an aluminum phosphate indurating impregnant comprising phosphoric acid and hydrated alumina (Alcoa C-31) in a mol ratio of 321.4, prepared by combining 52 lbs. of hydrated alumina with 166 lbs. of phosphoric acid (85%) and upon completion of the reaction diluted with sutficient water to produce a 25% solution. The average pick-up was 21% by weight.
  • the saturated boards were dried at approximately 200 F. and portions thereof were cut for testing.
  • the method of manufacturing mountings for electrical resistance elements which comprises treating millboard consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5% by weight of alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, by accumulating a higher concentration of indurating impregnant in the peripheral edge portion of the cut millboard mounting impregnated with an aqueous solution of aluminum acid phosphate indurant and containing at least about by weight of aluminum acid phosphate solute, comprising the step of blanketing the millboard mounting while wet on its two major surfaces to impede egress of the absorbed aqueous impregnating solution from these surfaces and to direct migration of the aqueous impregnating solution to the o peripheral edge portion and permit escape of the water content therefrom.
  • alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof
  • the method of manufacturing mountings for electrical resistance elements which comprises treating millboard consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5% by weight of alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof by impregnating the same with an indurating aqueous solution of aluminum acid phosphate until the millboard retains at least about 15 by weight of solute, accumulating a higher concentration of the indurating impregnant in the peripheral edge portion of the millboard mounting to reinforce the same by cutting the millboard to its ultimate configuration while wet with the absorbed aqueous impregnating solution, then blanketing the wet millboard mounting on its two major surfaces to impede egress of the absorbed aqueous impregnating solution from these surfaces and to direct migration of the aqueous impregnating solution to the peripheral edge portion of the mounting and permit escape of the water content therefrom.
  • alkali metal silicate selected from the group
  • the method of manufacturing mountings for electrical resistance elements which comprises treating millboard consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5 by weight of alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, by cutting the millboard to its ultimate configuration and impregnating the same with an indurating aqueous solution of aluminum acid phosphate until the millboard retains at least about 15 by weight of solute, accumulating a higher concentration of the indurating impregnant in the peripheral edge portion of the millboard mounting to reinforce the same by blanketing the wet millboard mounting on its two major surfaces to impede egress of the absorbed aqueous impregnating solution from the surfaces and to direct migration of the aqueous impregnating solution to the periph eral edge portion of the mounting and permit escape of the water content therefrom.
  • the method of manufacturing mountings for electrical resistance elements which comprises treating millboard consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45 by weight of diatomaceous earth and approximately 7.5 to 12.5% by weight of alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, by impregnating the same with an indurating aqueous solution of aluminum acid phosphate until the millboard retains about 15 to 40% by weight of solute, accumulating a higher concentration of the indurating impregnant in the peripheral edge portion of the millboard mounting to reinforce the same by completing the cutting of the millboard to its ultimate configuration while wet with the absorbed aqueous impregnating solution, then blanketing the wet millboard mounting on its two major surfaces to impede egress of the absorbed aqueous impregnating solution from these surfaces and to direct migration of the aqueous impregnating solution to the peripheral edge portions of the mounting and permit escape of the water content therefrom.
  • alkali metal silicate
  • the method of manufacturing mountings for electrical resistance elements which comprises treating millboard consisting essentially of approximately 50% by weight of asbestos fiber, approximately 40% by weight of diatomaceous earth and approximately 10% by weight of alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, by impregnating the same with an indurating aqueous solution of aluminum acid phosphate until the millboard retains at least about 20 to 30% by weight of the solute, accumulating a higher concentration of the indurating impregnant in the peripheral edge portion of the millboard mounting to reinforce the same by cutting the millboard to its ultimate configuration while wet with the absorbed aqueous impregnating solution, then blanketing the wet millboard mounting on its two major surfaces to impede egress of the absorbed aqueous impregnating solution from these surfaces and to direct migration of the aqueous impregnating solution to the peripheral edge portion of the mounting and permit escape of the water content therefrom.
  • the method of manufacturing mountings for electrical resistance elements which comprises forming a millboard from a furnish consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5% by weight of dry alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, activating the dry alkali metal silicate binder by exposing the formed millboard to high temperature and moisture conditions to solubilize the same, indurating the millboard by impregnating the same with an aqueous solution of aluminum acid phosphate until it retains at least about 15% by weight of solute and accumulating a higher concentration of the indurating impregnant in the peripheral edge portion of the millboard mounting to reinforce the same by cutting the millboard to its ultimate configuration either before or upon completion of the impregnating treatment but prior to drying of the absorbed aqueous impregnating solution from the millboard, then blanketing the wet millboard mounting on its two major surfaces to impede egress of
  • the method of manufacturing mountings for electrical resistance elements which comprises forming a millboard from a furnish consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45 by weight of diatomaceous earth and approximately 7.5 to 12.5% by weight of dry alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, activating the dry alkali metal silicate binder by exposing the formed millboard to high temperature and moisture conditions to solubilize the same, indurating the millboard by impregnating the same with an aqueous solution of aluminum acid phosphate until it retains at least about 15 by Weight of the solute and accumulating a higher concentration of the indurating impregnant in the peripheral edge portion of the millboard mounting to reinforce the same by cutting the millboard to its ultimate configuration prior to drying of the absorbed aqueous impregnating solution, then blanketing the wet millboard mounting on its two major surfaces to impede egress of the absorbed aqueous impregnating solution from these surfaces and to
  • the method of manufacturing mountings for electrical resistance elements which comprises forming a millboard from a furnish consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5 by weight of dry alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, activating the dry alkali metal silicate binder by exposing the formed billboard to high temperature and moisture conditions to solubilize the same, cutting the millboard to its ultimate configuration and indurating the same by impregnating it with an aqueous solution of aluminum acid phosphate until the millboard retains at least about 15% by weight of solute and accumulating a higher con- 10 centration of indurating impregnant in the peripheral edge portion of the millboard mounting to reinforce the same by blanketing the wet millboard mounting on its two major surfaces to impede egress of the absorbed aqueous solution from these surfaces and to direct migration of the aqueous impregnating solution to the peripheral edge portion
  • the method of manufacturing mountings for electrical resistance elements which comprises forming a millboard from a furnish consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth, and approximately 7.5 to 12.5 by weight of dry alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, activating the dry alkali metal silicate binder by exposing the formed millboard to temperatures of at least about 200 F.
  • the method of manufacturing mountings for electrical resistance elements which comprises forming a millboard from a furnish consisting essentially of approximately 50% by weight of asbestos fiber, approximately 40% by weight of diatomaceous earth and approximately 10% by weight of dry sodium silicate, activating the dry sodium silicate binder by exposing the formed millboard to temperatures of about 200-400 F.
  • a mounting for electrical resistance elements which consists essentially of a millboard composed of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5 by weight of solubilized in situ alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, containing at least about 15% by weight of aluminum acid phosphate and the reaction products of the millboard and aluminum acid phosphate, said aluminum acid phosphate and the reaction products of the same with the millboard being present in a higher concentration in the peripheral edge portion of the millboard mounting than in the intermediate portion thereof.
  • a mounting for electrical resistance elements which consists essentially of a millboard composed of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5% by weight of solubilized in situ alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, containing about 15 to 40% by weight of aluminum acid phosphate and the reaction product of the millboard and the aluminum acid phosphate, said aluminum acid phosphate and the reaction products of the same with the millboard being present in a higher concentration in the peripheral edge portion of the millboard mounting than in the' intermediate portion thereof.
  • a mounting for electrical resistance elements which consists essentially of a millboard prepared from a furnish consisting essentially of approximately 40 to 60% by weight of asbestos fiber, approximately 35 to 45% by weight of diatomaceous earth and approximately 7.5 to 12.5% by weight of solubilized in situ alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, containing about 15 to 40% by weight of aluminum acid phosphate and the reaction products of the millboard and the aluminum acid phosphate, said aluminum acid phosphate and the reaction products of the same With the millboard being present in a higher concentration in the peripheral edge portion of the millboard mounting than in the intermediate portion thereof.
  • a mounting for electrical resistance elements which consists essentially of a millboard prepared from a furnish consisting essentially of approximately 50% by weight of asbestos fiber, approximately 40% by Weight of diatomaceous earth and approximately 10% by weight of solubilized in situ alkali metal silicate selected from the group consisting of sodium silicate and potassium silicate and mixtures thereof, containing about 20 to 30% by weight of aluminum acid phosphate and the reaction products of the millboard and aluminum acid phosphate, said aluminum acid phosphate and the reaction products of the same with the millboard being present in a higher concentration in the peripheral edge portion of the millboard mounting than in the intermediate portion thereof.
  • a mounting for electrical resistance elements which consists essentially of a millboard prepared from a furnish consisting essentially of approximately 50% by weight of asbestos fiber, approximately 40% by Weight of diatomaceous earth and approximately 10% by Weight or" solubilized in situ sodium silicate, containing about 20 to 30% by weight of aluminum acid phosphate and the reaction products of the millboard and aluminum acid phosphate, said aluminum acid phosphate and the reaction products of the same with the millboard being present in a higher concentration in the peripheral edge portion of the millboard mounting than in the intermediate portion thereof.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Inorganic Chemistry (AREA)
  • Ceramic Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Materials Engineering (AREA)
  • Structural Engineering (AREA)
  • Organic Chemistry (AREA)
  • Fireproofing Substances (AREA)
  • Insulating Bodies (AREA)
US62140A 1960-10-12 1960-10-12 Mounting for electrical resistance elements and method for preparing the same Expired - Lifetime US3053727A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US62140A US3053727A (en) 1960-10-12 1960-10-12 Mounting for electrical resistance elements and method for preparing the same
GB33623/61A GB943864A (en) 1960-10-12 1961-09-20 Mounting for electrical resistance elements and method for preparing the same
BE608953A BE608953A (fr) 1960-10-12 1961-10-09 Monture d'éléments de résistance électrique et leur procédé de fabrication.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US62140A US3053727A (en) 1960-10-12 1960-10-12 Mounting for electrical resistance elements and method for preparing the same

Publications (1)

Publication Number Publication Date
US3053727A true US3053727A (en) 1962-09-11

Family

ID=22040461

Family Applications (1)

Application Number Title Priority Date Filing Date
US62140A Expired - Lifetime US3053727A (en) 1960-10-12 1960-10-12 Mounting for electrical resistance elements and method for preparing the same

Country Status (3)

Country Link
US (1) US3053727A (fr)
BE (1) BE608953A (fr)
GB (1) GB943864A (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3212960A (en) * 1962-12-04 1965-10-19 Johns Manville Asbestos-glass fiber saturating paper containing thermoplastic resin and aluminum acid phosphate
US3493463A (en) * 1966-05-10 1970-02-03 Bird Machine Co Process and apparatus for forming a high strength band along the length of a paper web
US20090149310A1 (en) * 2007-01-19 2009-06-11 Dean Veral Neubauer Pulling roll material for manufacture of sheet glass

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5057349A (en) * 1990-03-02 1991-10-15 William Perry Insert for use in fabric-painting

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1780623A (en) * 1929-07-26 1930-11-04 Emil C Loetscher Process for manufacturing building material of varying densities
US1812969A (en) * 1926-03-01 1931-07-07 Masonite Corp Process of making integral insulating board with hard welded surfaces
US2341645A (en) * 1940-05-16 1944-02-15 Celotex Corp Tiling
US2541273A (en) * 1947-10-13 1951-02-13 Proctor Electric Co Support for high resistance electrical conductors and method of making the same
US2702761A (en) * 1949-07-12 1955-02-22 Celotex Corp Method of impregnating fiber insulation board
US2826236A (en) * 1954-05-29 1958-03-11 Balzaretti Modigliani Spa Method and apparatus for uninterrupted production of surface coated layers of bondedmineral wool

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1812969A (en) * 1926-03-01 1931-07-07 Masonite Corp Process of making integral insulating board with hard welded surfaces
US1780623A (en) * 1929-07-26 1930-11-04 Emil C Loetscher Process for manufacturing building material of varying densities
US2341645A (en) * 1940-05-16 1944-02-15 Celotex Corp Tiling
US2541273A (en) * 1947-10-13 1951-02-13 Proctor Electric Co Support for high resistance electrical conductors and method of making the same
US2702761A (en) * 1949-07-12 1955-02-22 Celotex Corp Method of impregnating fiber insulation board
US2826236A (en) * 1954-05-29 1958-03-11 Balzaretti Modigliani Spa Method and apparatus for uninterrupted production of surface coated layers of bondedmineral wool

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3212960A (en) * 1962-12-04 1965-10-19 Johns Manville Asbestos-glass fiber saturating paper containing thermoplastic resin and aluminum acid phosphate
US3493463A (en) * 1966-05-10 1970-02-03 Bird Machine Co Process and apparatus for forming a high strength band along the length of a paper web
US20090149310A1 (en) * 2007-01-19 2009-06-11 Dean Veral Neubauer Pulling roll material for manufacture of sheet glass
US7842632B2 (en) * 2007-01-19 2010-11-30 Corning Incorporated Pulling roll material for manufacture of sheet glass

Also Published As

Publication number Publication date
GB943864A (en) 1963-12-11
BE608953A (fr) 1962-04-09

Similar Documents

Publication Publication Date Title
BR7703928A (pt) Processo para a fabricacao de uma estrutura superficial porosa de fibras de vidro,tendo estabilidade de forma e resistente ao calor e a corrosao bem como estrutura produzida de acordo com o mesmo
DE1282598B (de) Verfahren zum Flammfestmachen von cellulosehaltigem Material
US3053727A (en) Mounting for electrical resistance elements and method for preparing the same
US1856475A (en) Metal impregnated fiber article and process of making same
SE8504494L (sv) Forfarande for framstellning av fuktutbyteselement
US1738976A (en) Process for fireproofing cellulose
US3090699A (en) Sag-resistant fiberboard and method of making same
SE8303997D0 (sv) Article and composition for clothes conditioning and method of making and using same
JPH11350318A5 (fr)
US1945714A (en) Process of impregnating porous material with solid substances
US2541273A (en) Support for high resistance electrical conductors and method of making the same
EP0255950B1 (en) Method of manufacturing fibre boards
US1738044A (en) Electric material and process for making same
US1857498A (en) Treatment of pulp articles and material therefor
US3423195A (en) Method of treating alumina abrasive grains with iron nitrate and products made thereby
US3498774A (en) Process for improved high silica fibers
US1765312A (en) Insulating materials and process of manufacture of same
US2329051A (en) Process for producing molded products
DE869512C (de) Isolationspaste fuer Heizfadenbedeckung
FR2322248A1 (fr) Element de construction en forme de plaque
US2106468A (en) Method of making wood products
US3096200A (en) Method of preparing inorganic products
IT959680B (it) Procedimento di fabbricazione di composizioni fibrose impregnate di resine poliestere
US1770663A (en) Thermal and electrical insulator and process of manufacture thereof
IT1110965B (it) Elemento strutturale in allominio o lamiera di ferro stagnata imbutita,e procedimento per fabbricarla