GB2068978A - Friction Materials Comprising Rubber Binder and Aromatic Polyamide Fibre - Google Patents
Friction Materials Comprising Rubber Binder and Aromatic Polyamide Fibre Download PDFInfo
- Publication number
- GB2068978A GB2068978A GB8003745A GB8003745A GB2068978A GB 2068978 A GB2068978 A GB 2068978A GB 8003745 A GB8003745 A GB 8003745A GB 8003745 A GB8003745 A GB 8003745A GB 2068978 A GB2068978 A GB 2068978A
- Authority
- GB
- United Kingdom
- Prior art keywords
- percent
- brake shoe
- weight
- filler
- friction
- 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.)
- Granted
Links
- 229920001971 elastomer Polymers 0.000 title claims abstract description 36
- 239000005060 rubber Substances 0.000 title claims abstract description 36
- 239000000835 fiber Substances 0.000 title claims abstract description 27
- 239000011230 binding agent Substances 0.000 title claims abstract description 25
- 239000002783 friction material Substances 0.000 title claims abstract description 18
- 239000004760 aramid Substances 0.000 title abstract description 21
- 229920003235 aromatic polyamide Polymers 0.000 title abstract description 19
- 239000000203 mixture Substances 0.000 claims abstract description 37
- 239000000945 filler Substances 0.000 claims abstract description 36
- 230000003014 reinforcing effect Effects 0.000 claims abstract description 9
- 239000002131 composite material Substances 0.000 claims description 38
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 29
- 239000000463 material Substances 0.000 claims description 26
- TZCXTZWJZNENPQ-UHFFFAOYSA-L barium sulfate Chemical compound [Ba+2].[O-]S([O-])(=O)=O TZCXTZWJZNENPQ-UHFFFAOYSA-L 0.000 claims description 24
- 239000003921 oil Substances 0.000 claims description 23
- 229920000642 polymer Polymers 0.000 claims description 21
- 244000226021 Anacardium occidentale Species 0.000 claims description 16
- 235000020226 cashew nut Nutrition 0.000 claims description 16
- 238000010521 absorption reaction Methods 0.000 claims description 14
- 229910052742 iron Inorganic materials 0.000 claims description 14
- 229920005989 resin Polymers 0.000 claims description 13
- 239000011347 resin Substances 0.000 claims description 13
- 239000012764 mineral filler Substances 0.000 claims description 12
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims description 10
- -1 chloro-substituted p-phenylene Chemical group 0.000 claims description 9
- 239000003607 modifier Substances 0.000 claims description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 7
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 claims description 7
- 239000000395 magnesium oxide Substances 0.000 claims description 7
- 125000001140 1,4-phenylene group Chemical group [H]C1=C([H])C([*:2])=C([H])C([H])=C1[*:1] 0.000 claims description 6
- 150000004684 trihydrates Chemical class 0.000 claims description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical group [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 5
- INJRKJPEYSAMPD-UHFFFAOYSA-N aluminum;silicic acid;hydrate Chemical compound O.[Al].[Al].O[Si](O)(O)O INJRKJPEYSAMPD-UHFFFAOYSA-N 0.000 claims description 5
- 239000010443 kyanite Substances 0.000 claims description 5
- 229910052850 kyanite Inorganic materials 0.000 claims description 5
- 239000011159 matrix material Substances 0.000 claims description 5
- 229920003002 synthetic resin Polymers 0.000 claims description 5
- 239000004927 clay Substances 0.000 claims description 4
- 239000010439 graphite Substances 0.000 claims description 4
- 229910002804 graphite Inorganic materials 0.000 claims description 4
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims description 4
- 239000004576 sand Substances 0.000 claims description 4
- 239000007787 solid Substances 0.000 claims description 4
- 229920003048 styrene butadiene rubber Polymers 0.000 claims description 4
- 239000000057 synthetic resin Substances 0.000 claims description 4
- CBCKQZAAMUWICA-UHFFFAOYSA-N 1,4-phenylenediamine Chemical compound NC1=CC=C(N)C=C1 CBCKQZAAMUWICA-UHFFFAOYSA-N 0.000 claims description 3
- 239000004908 Emulsion polymer Substances 0.000 claims description 3
- 239000002174 Styrene-butadiene Substances 0.000 claims description 3
- RHZUVFJBSILHOK-UHFFFAOYSA-N anthracen-1-ylmethanolate Chemical compound C1=CC=C2C=C3C(C[O-])=CC=CC3=CC2=C1 RHZUVFJBSILHOK-UHFFFAOYSA-N 0.000 claims description 3
- 239000003830 anthracite Substances 0.000 claims description 3
- MTAZNLWOLGHBHU-UHFFFAOYSA-N butadiene-styrene rubber Chemical compound C=CC=C.C=CC1=CC=CC=C1 MTAZNLWOLGHBHU-UHFFFAOYSA-N 0.000 claims description 3
- 239000003795 chemical substances by application Substances 0.000 claims description 3
- 239000003245 coal Substances 0.000 claims description 3
- CZZYITDELCSZES-UHFFFAOYSA-N diphenylmethane Chemical class C=1C=CC=CC=1CC1=CC=CC=C1 CZZYITDELCSZES-UHFFFAOYSA-N 0.000 claims description 3
- 239000005350 fused silica glass Substances 0.000 claims description 3
- 239000002245 particle Substances 0.000 claims description 3
- 239000011115 styrene butadiene Substances 0.000 claims description 3
- MHSKRLJMQQNJNC-UHFFFAOYSA-N terephthalamide Chemical compound NC(=O)C1=CC=C(C(N)=O)C=C1 MHSKRLJMQQNJNC-UHFFFAOYSA-N 0.000 claims description 3
- 238000000354 decomposition reaction Methods 0.000 claims description 2
- 229940056932 lead sulfide Drugs 0.000 claims description 2
- 229910052981 lead sulfide Inorganic materials 0.000 claims description 2
- 239000010458 rotten stone Substances 0.000 claims description 2
- 239000005995 Aluminium silicate Substances 0.000 claims 1
- 229910000323 aluminium silicate Inorganic materials 0.000 claims 1
- PZZYQPZGQPZBDN-UHFFFAOYSA-N aluminium silicate Chemical compound O=[Al]O[Si](=O)O[Al]=O PZZYQPZGQPZBDN-UHFFFAOYSA-N 0.000 claims 1
- 235000012211 aluminium silicate Nutrition 0.000 claims 1
- 239000011435 rock Substances 0.000 claims 1
- 239000004636 vulcanized rubber Substances 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 4
- 235000019198 oils Nutrition 0.000 description 21
- 239000010425 asbestos Substances 0.000 description 14
- 229910052895 riebeckite Inorganic materials 0.000 description 14
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 description 9
- VKYKSIONXSXAKP-UHFFFAOYSA-N hexamethylenetetramine Chemical compound C1N(C2)CN3CN1CN2C3 VKYKSIONXSXAKP-UHFFFAOYSA-N 0.000 description 8
- 229920001568 phenolic resin Polymers 0.000 description 8
- 229920005594 polymer fiber Polymers 0.000 description 8
- 239000000843 powder Substances 0.000 description 8
- 239000005011 phenolic resin Substances 0.000 description 7
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 description 5
- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 5
- 239000006229 carbon black Substances 0.000 description 5
- 239000007788 liquid Substances 0.000 description 5
- 229920003368 Kevlar® 29 Polymers 0.000 description 4
- 125000003118 aryl group Chemical group 0.000 description 4
- 239000010428 baryte Substances 0.000 description 4
- 229910052601 baryte Inorganic materials 0.000 description 4
- 239000004312 hexamethylene tetramine Substances 0.000 description 4
- 235000010299 hexamethylene tetramine Nutrition 0.000 description 4
- 239000011256 inorganic filler Substances 0.000 description 4
- 229910003475 inorganic filler Inorganic materials 0.000 description 4
- WABPQHHGFIMREM-UHFFFAOYSA-N lead(0) Chemical compound [Pb] WABPQHHGFIMREM-UHFFFAOYSA-N 0.000 description 4
- 229960004011 methenamine Drugs 0.000 description 4
- YEXPOXQUZXUXJW-UHFFFAOYSA-N oxolead Chemical compound [Pb]=O YEXPOXQUZXUXJW-UHFFFAOYSA-N 0.000 description 4
- 239000000047 product Substances 0.000 description 4
- 239000012783 reinforcing fiber Substances 0.000 description 4
- 230000000979 retarding effect Effects 0.000 description 4
- 229920003051 synthetic elastomer Polymers 0.000 description 4
- 239000005061 synthetic rubber Substances 0.000 description 4
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 3
- 229920006231 aramid fiber Polymers 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 125000002485 formyl group Chemical class [H]C(*)=O 0.000 description 3
- 239000003365 glass fiber Substances 0.000 description 3
- 235000021388 linseed oil Nutrition 0.000 description 3
- 239000000944 linseed oil Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000011787 zinc oxide Substances 0.000 description 3
- YXIWHUQXZSMYRE-UHFFFAOYSA-N 1,3-benzothiazole-2-thiol Chemical compound C1=CC=C2SC(S)=NC2=C1 YXIWHUQXZSMYRE-UHFFFAOYSA-N 0.000 description 2
- 239000004484 Briquette Substances 0.000 description 2
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- 229910001018 Cast iron Inorganic materials 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 2
- 229920000271 Kevlar® Polymers 0.000 description 2
- 229920000297 Rayon Polymers 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000005864 Sulphur Substances 0.000 description 2
- YKTSYUJCYHOUJP-UHFFFAOYSA-N [O--].[Al+3].[Al+3].[O-][Si]([O-])([O-])[O-] Chemical compound [O--].[Al+3].[Al+3].[O-][Si]([O-])([O-])[O-] YKTSYUJCYHOUJP-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 239000002008 calcined petroleum coke Substances 0.000 description 2
- 229910000019 calcium carbonate Inorganic materials 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 239000006185 dispersion Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000002657 fibrous material Substances 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 229910010272 inorganic material Inorganic materials 0.000 description 2
- 239000011147 inorganic material Substances 0.000 description 2
- 239000004761 kevlar Substances 0.000 description 2
- 229910000464 lead oxide Inorganic materials 0.000 description 2
- XCAUINMIESBTBL-UHFFFAOYSA-N lead(ii) sulfide Chemical compound [Pb]=S XCAUINMIESBTBL-UHFFFAOYSA-N 0.000 description 2
- 230000003137 locomotive effect Effects 0.000 description 2
- 229920003052 natural elastomer Polymers 0.000 description 2
- 229920001194 natural rubber Polymers 0.000 description 2
- 239000011368 organic material Substances 0.000 description 2
- 150000002989 phenols Chemical class 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 229920003366 poly(p-phenylene terephthalamide) Polymers 0.000 description 2
- 239000002964 rayon Substances 0.000 description 2
- 239000012779 reinforcing material Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 239000003351 stiffener Substances 0.000 description 2
- 238000005728 strengthening Methods 0.000 description 2
- 125000001424 substituent group Chemical group 0.000 description 2
- 229920001187 thermosetting polymer Polymers 0.000 description 2
- NLHHRLWOUZZQLW-UHFFFAOYSA-N Acrylonitrile Chemical compound C=CC#N NLHHRLWOUZZQLW-UHFFFAOYSA-N 0.000 description 1
- 244000198134 Agave sisalana Species 0.000 description 1
- 229910001369 Brass Inorganic materials 0.000 description 1
- 240000000491 Corchorus aestuans Species 0.000 description 1
- 235000011777 Corchorus aestuans Nutrition 0.000 description 1
- 235000010862 Corchorus capsularis Nutrition 0.000 description 1
- 229920000742 Cotton Polymers 0.000 description 1
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 1
- 235000019738 Limestone Nutrition 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 239000004952 Polyamide Substances 0.000 description 1
- 229920001131 Pulp (paper) Polymers 0.000 description 1
- 229910001037 White iron Inorganic materials 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 150000008430 aromatic amides Chemical class 0.000 description 1
- 150000004984 aromatic diamines Chemical class 0.000 description 1
- 239000010951 brass Substances 0.000 description 1
- 229920005549 butyl rubber Polymers 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 125000005521 carbonamide group Chemical group 0.000 description 1
- 229920005556 chlorobutyl Polymers 0.000 description 1
- 238000004581 coalescence Methods 0.000 description 1
- 239000007859 condensation product Substances 0.000 description 1
- 229920001577 copolymer Polymers 0.000 description 1
- 239000007799 cork Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- KZHJGOXRZJKJNY-UHFFFAOYSA-N dioxosilane;oxo(oxoalumanyloxy)alumane Chemical compound O=[Si]=O.O=[Si]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O.O=[Al]O[Al]=O KZHJGOXRZJKJNY-UHFFFAOYSA-N 0.000 description 1
- 239000013536 elastomeric material Substances 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 210000003746 feather Anatomy 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 125000004836 hexamethylene group Chemical group [H]C([H])([*:2])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[*:1] 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 150000002611 lead compounds Chemical class 0.000 description 1
- 239000006028 limestone Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 230000013011 mating Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000010445 mica Substances 0.000 description 1
- 229910052618 mica group Inorganic materials 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910052863 mullite Inorganic materials 0.000 description 1
- GHLZUHZBBNDWHW-UHFFFAOYSA-N nonanamide Chemical group CCCCCCCCC(N)=O GHLZUHZBBNDWHW-UHFFFAOYSA-N 0.000 description 1
- 150000002894 organic compounds Chemical class 0.000 description 1
- 239000012766 organic filler Substances 0.000 description 1
- 229920000620 organic polymer Polymers 0.000 description 1
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
- 239000002006 petroleum coke Substances 0.000 description 1
- 229920002239 polyacrylonitrile Polymers 0.000 description 1
- 229920002647 polyamide Polymers 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 239000002952 polymeric resin Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 239000012744 reinforcing agent Substances 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000004901 spalling Methods 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 229920002994 synthetic fiber Polymers 0.000 description 1
- 239000012209 synthetic fiber Substances 0.000 description 1
- KUAZQDVKQLNFPE-UHFFFAOYSA-N thiram Chemical compound CN(C)C(=S)SSC(=S)N(C)C KUAZQDVKQLNFPE-UHFFFAOYSA-N 0.000 description 1
- 229960002447 thiram Drugs 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Classifications
-
- 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
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D69/00—Friction linings; Attachment thereof; Selection of coacting friction substances or surfaces
- F16D69/02—Composition of linings ; Methods of manufacturing
- F16D69/025—Compositions based on an organic binder
- F16D69/026—Compositions based on an organic binder containing fibres
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/01—Use of inorganic substances as compounding ingredients characterized by their specific function
- C08K3/013—Fillers, pigments or reinforcing additives
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K7/00—Use of ingredients characterised by shape
- C08K7/02—Fibres or whiskers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L21/00—Compositions of unspecified rubbers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L9/00—Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
- C08L9/06—Copolymers with styrene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L77/00—Compositions of polyamides obtained by reactions forming a carboxylic amide link in the main chain; Compositions of derivatives of such polymers
- C08L77/10—Polyamides derived from aromatically bound amino and carboxyl groups of amino-carboxylic acids or of polyamines and polycarboxylic acids
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L99/00—Compositions of natural macromolecular compounds or of derivatives thereof not provided for in groups C08L89/00 - C08L97/00
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Braking Arrangements (AREA)
Abstract
Friction materials suitable for the manufacture of railroad brake shoes comprise a mixture of a curable rubber binder having distributed therethrough a plurality of fillers capable of absorbing binder decomposed during braking and reinforcing aromatic polyamide fibers.
Description
SPECIFICATION
Composite Friction Element 1. Field of the Invention
The present invention relates to friction elements and more particularly, to composite friction element useful as brake shoes for railroad brakes which element is devoid of asbestos.
2. The Prior Art
Brake shows for railroad brakes of the composition type are formed of a composite friction material composed of a rubber binder resin, having distributed therethrough a variety of fillers and a reinforcing fiber such as asbestos. Examples of composite friction elements used in the manufacture of the brake shoes are disclosed in U.S. Patents 3,885,006 and U.S. 3,959,194.
U.S. 3,885,006 teaches composite friction elements formed of 1 5-35% by weight of a resin binder, 45-65% by weight asbestos and 310% by weight of one or more fillers which function to impart increased hardness and wear resistance to the brake shoe or function as friction modifiers.
Fillers which are disclosed as imparting increased hardness to the brake shoe include barytes such as BaSO4, alumina (A1203), zinc and limestone (CaC03). Fillers which function as friction modifiers include brass powder, iron powder, carbon black, around cork and aldehyde condensation products of cashew nut liquid.
U.S. 3,959,194 teaches composite friction elements which are useful as brake shoes for railroad rolling stock with relatively soft steel wheels. The friction element is composed of 325% by weight of a rubber binder, 20-70% by weight of an inorganic filler and 212% by weight of a fiber. The fiber component disclosed in the patent is composed of asbestos fibers or a cellulosic fiber such as wood, sisal, jute and rayon fibers. The rubber binder is a natural or synthetic rubber or an elastomeric material which is vulcanized or otherwise cured to form a hard matrix in which the remaining components are distributed. A phenolic resin at a concentration of 130% is incorporated in the composition of the friction element as a strengthening or stiffening agent for the rubber matrix.Phenolic resins disclosed in the patent include oil-modified two-stage powdered phenol formaldehyde resins and a liquid resin prepared from natural sources of phenol derivatives derived from aldehyde reacted cashew nut shell oil and containing a curing agent such as hexamethylene tetramine. Among the inorganic fillers disclosed in U.S. 3,959,194 include graphite, cast iron, iron oxide, calcium carbonate, barytes and carbon black.
In forming composite friction elements, the inorganic fillers are added for various purposes. For example, the hard mineral fillers such as iron grit are added for their frictional properties, fillers such as lead oxide are included to modify the frictional effect of the hard mineral fillers; lead powder acts as a lubricant and friction modifier; asbestos fibers as a friction reinforcing agent contributing high physical strength to produce uniformly high friction against ferrous mating surfaces such as railroad car wheels, and withstand high braking temperatures. The rubber resin binds and holds together the mixture of materials.
Asbestos has been generally satisfactory as a reinforcing fiber for use in friction elements, but recent environmental studies have revealed that asbestos may have a detrimental effects on the health of those who are exposed to its presence and, therefore, it is currently desirable to seek alternative compositions in which the asbestos content of brake shoes is reduced or eliminated.
Heretofore, attempts to substitute other fibers for asbestos generally have failed to produce satisfactory friction elements. For example, glass and ceramic fibers fracture in the mixing procedures used to prepare the brake shoe compositions with the result that they contribute poor reinforcement.
Furthermore, glass fibers are brittle and tend to break down at the breaking interface during service of the brake shoe and high wear rates are thereby encountered. Moreover, the nonporous glass surfaces have a low surface area as compared with asbestos, and the glass fibers do not absorb products of decomposition of the organic components caused by heat which occurs during braking. As a result, when glass fibers are used as the reinforcing material, friction drops precipitously at the temperatures generated during braking. This friction drop due to poor absorption by the reinforcing fibers is known in the brake shoes industry as "fade".
Organic fibers such as cotton, wood pulp and rayon, synthetic fibers composed of such organic polymers as polyacrylonitrile, polyamide, polyester and the like have low surface area and exhibit poor heat resistance. These latter fiber materials lose strength at temperatures in the range of 2000-- 300 F (93--1 49 OC) and break down in the same manner as the rubber binder. In fact, a small amount of organic fiber is often added to an asbestos reinforced composite friction element to introduce a slight controlled "fade" to save the brake from destruction when the brake is used beyond its rated capacity.
It is the primary object of the present invention to provide an asbestos-free composite friction element suitable for brake shoe application and which is capable of withstanding high temperatures, has high physical strength, provides good braking characteristics particularly applicable to railroad braking, and meets the test standards of the AAR (American Association of Railroads) for brake shoes made with a blend of organic and/or inorganic materials.
Summary of the Invention
In accordance with the present invention there is provided a composite friction element suitable for the manufacture of high friction composition type railroad brake shoes which are devoid of asbestos and will withstand the braking parameters associated with the deceleration of railroad locomotives, the composite element being comprised of a rubber (as hereinafter defined) binder having distributed therethrough a plurality of fillers at least one of which has an oil absorption value of at least 30 and a fiber formed from an aramid polymer.
Brake shoes made from the asbestos-free-composite friction materials of the present invention meet the AAR standards for high friction composition type brake shoes.
Description of the Preferred Embodiments
The precise composition of the composite friction element of the present invention may be widely varied, but in all instances the element contains a rubber binder represented at least in part by a vulcanizable rubber or a mixture thereof containing dispersed filler particles having high oil absorption values and aramid polymer fibers which impart wear resistance, afford the desired level of friction coefficient and which reinforce or strengthen the composite element as a whole.
The asbestos-free composite friction element of the present invention may have the following
representative compositional range in approximate percent by weight:
Approximate Percentage
Component Range by Weight
1. Curable rubber binder 1530% 2. Hard Mineral Fillers 2550% 3. Friction Modifiers 1530% 4. Reinforcing aramid fiber 0.510.0% 5. Absorptive Fillers having an Oil Absorption
Value in excess of 30 2050% If the above-noted components were measured as a percentage range by volume, the range for each would be much narrower. Because the density of the above components vary so significantly, the percentage range by weight varies accordingly.For example, the percentage range by volume of a filler
material such as sand or iron grit would be narrow, but because of the difference in density of these two materials, the iron grit becomes a dominant material when viewed in percentage by weight. The percentage range by weight of the other components are affected accordingly.
The rubber binder used in the practice of the present invention can be any of the rubber binder materials conventionally used by the railroad brake art for the manufacture of brake shoes. Such rubber materials include unvulcanized natural and synthetic rubber or elastomeric materials that can be vulcanized or otherwise cured in situ to form a hard matrix for the remaining components of the composite friction materials of the present invention. Examples of such rubbers are the butyl rubbers, styrene-butadiene copolymer rubbers, acrylonitrile rubbers and chlorinated butyl rubber. These rubbers are vulcanized with the aid of vulcanizing catalysts such as sulfur, 2-mercaptobenzothiazole, tetramethylthiuram disulfide and mixtures thereof which accelerate the rate of cure of the rubber.The vulcanizing catalyst are included in the rubber binder composition in minor amounts, e.g., at concentrations in the range of about 1 to about 3 percent by weight based on the weight of the composite friction element.
Also included in the rubber binder composition may be conventional rubber fillers such as carbon black, zinc oxide, lead oxide, lead powder, MgO and ZnO. These fillers are generally incorporated in the rubber binder at concentrations ranging from about 5 to 1 5 percent by weight based on the weight of the composite friction element.
Thermosetting resins such as phenol-aldehyde resins may also be incorporated in the rubber binder composition as a strengthening or stiffening agent for the rubber matrix. The phenolic resin may be a synthetic resin prepared from conventional organic compounds such as phenol and formaldehyde.
Alternatively, the phenolic resin may be a resin prepared from natural sources of phenol derivatives such as cashew nut shell oil, which oils are reacted with aldehydes to impart thermosetting properties thereto. Typically, the phenolic resins are incorporated in the rubber binder composition at concentrations in the range of about 1 to about 10 percent by weight based on the weight of the composite friction element. Curing agents such as hexamethylenetetramine are included in the phenolic resin, in relatively small amounts, e.g., about 0.2 to about 1.0 percent by weight based on the weight of the composite friction element to accelerate the cure of the phenolic resin.
Hard mineral fillers can be incorporated in the brake shoe composition to promote friction in the brake shoes prepared from the composite fricticn materials of the present invention and include iron which may be in the form of iron ore or iron grit, as well as sand, fused silica, and calcined kyanite, i.e.
aluminiurn silicate.
Friction modifiers can be incorporated into the composite friction material to stabilize the coefficient of friction of the brake shoe under a variety of operating and climatic conditions to which the brake shoe will be exposed so as to provide wear resistance to the shoe and may be either organic or inorganic materials such as graphite, and partially cured cashew-resin solids, calcined kyanite (Al2SiO5), as well as lead and lead compounds such as lead sulfide.
Reinforcing aramid polymer fibers suitable for use in the practice of the present invention as a substitute for asbestos are commercially available from E.l. Du Pont de Nemours under the trade name "Kevlar". Exemplary of Kevlar fiber materials suitable for use in the practice of the present invention is
Kevlar 29, a continuous filament yarn having the following physical properties::
Table I
Kevlar 29 Physical Properties
Density 0.52 Ib/in3
Filament Diameter 0.00047 in
Denier per Filament 1.5
**Break Elongation
*Tensile Strength 400,000 psi
Tenacity 22 gpd
**Specific Tensile Strength 8x 106 in
*Modulus 9x106 in 480 gpd **Specific Modulus 2.3x 108 in
Temperature Resistance Useful properties from 4200F to 500dF (40%
decrease in tensile strength at 5000F).
*Dry yarn test
**Yarn property divided by density
The term "aramid polymer" as used in the present specification means a synthetic polymeric resin generally designated in the art as an aromatic polycarbonamide. "Aramid polymer" is a polymer such as described in U.S. Patents 3,652,510, U.S. 3,899,085 and U.S. 3,673,143 and is believed to be of a composition hereinafter described.In these patents, the polymers disclosed therein include fiber forming polymers of high molecular weight, e.g. having an inherent viscosity of at least about 0.7, characterized by recurring units of the formula
wherein Ar, is p-phenylene and/or chloro-substituted p-phenylene, and/or 4,4'-substituted diphenyl methane, i.e.,
and Ar2 is p-phenylene, i.e.,
Illustrative examples of polycarbonamides coming within the definition of the above formula are poly(p-phenylene terephthalamide) chloro-substituted poly(p-phenylene terephthalamide) and copolymers thereof.
The designation of the position of location of the substituent groups on the aromatic nuclei of the aramid polymer refers to the location of the substituents on the aromatic diamine, diacid or other coreactants from which the aramid polymer is prepared.
Although the aramid polymer or aromatic polycarbonamide may consist primarily of carbonamide links (-CONH-) and aromatic ring nuclei, conforming to the formula above, the polymer may contain up to 20 mole percent and preferably 0 to 5 mole percent of non-conforming comonomer units which provide units in the polycarbonamide chain different from
such as aromatic carbonamide units whose chain extending bonds are coaxial or parallel and oppositely directed, e.g.
meta-phenylene units, non-aromatic and non-amide groups.
A more comprehensive disclosure of the composition of aramid polymers is found in U.S.
3,673,143 as well as the divisional patent thereof, U.S. 3,817,941, the teachings of which are herein incorporated by reference.
Independent analytical tests and infra-red analysis have indicated that Kevlar 29 could be predominately (95% weight) poly(p-phenylene diamine terephthalamide and could be chemically described as poly(p-phenylene diamine terephthalamide)-co-poly(4,4'-diamino diphenyl methane terephthalamide).
It is critical to the practice of the present invention that the reinforcing fibers used in the composite friction element of the present invention be formed from aramid polymers. Thus during braking, railroad brake shoes encounter high quantities of energy in the form of heat generated by the frictional engagement of the brake shoe with the steel wheel of the railroad locomotive so as to raise the interface temperature of the shoe to temperatures in the order of 20000F (1 093 OC). It is believed that due to the relatively high tensile strength and temperature resistance of aramid fibers, e.g.
400.00Q psi (28.12x106g/cm2) and 420C--5000F (215--2600C) respectively, the aramid fibers when incorporated in the friction element of the present invention retain their functional properties as reinforcing materials when exposed to the high temperatures encountered in braking.
It is also critical to the practice of the present invention that high absorptive filler materials be used in combination with the reinforcing aramid polymer fiber. Filler materials suitable for this function are organic or inorganic fillers having a high surface area whereby the loss of absorptive capacity resulting from the absence of asbestos is replaced by the high absorptive filler. The term "high absorptive filler" as used in the present specification means a filler material determined to have an Oil
Absorption Value of at least 30.
The term "Oil Absorption Value" as used in the present specification means the milliliters of linseed oil required to wet a predetermined volume of the filler, i.e. 100 cubic centimeters (cc) of the filler.
In determining the Oil Absorption Value, a 20 grams portion of the filler powder is placed in shallow ceramic dish and raw linseed oil is metered into the dish from a burette. The linseed oil delivered by the burette is stirred and worked into the powder. The addition of the oil to the powder causes the powder to agglomerate into small balls which increase in size and decrease in number as more oil is metered from the burette into the dish. The addition of the oil is continued until the oil wetted powder coalesces into a single mass or ball of powder. The number of milliliters of oil which cause the coalescence of the powder into an integral, single bailed mass is multiplied by 5 to obtain the oil absorption number. The oil absorption number is then multiplied by the specific gravity of the filler, and this latter product is termed the oil absorption value. Listed below in Table II are the oil absorption values of a variety of filler materials useful in the practice of the present invention.
Table II
Oil Absorption Value of Fillers
Filler OilAbsorption Value
Alumina Trihydrate, type A 92
Alumina Trihydrate, type B 102
Alumina Trihydrate, type C 78
Barite (Barytes, Ba SO4) type A 49
Barite (Barytes, BaSO4) type B 63
Barite (Glassmakers coarse) 40
Barite (Glassmakers fine) 72
Rottenstone (Ground Shale, Penna.) 86
Anthracite Coal (99.9%--325 mesh) 72
Magnesium Oxide 83
Clay, Georgia rubber Grade A 138
Clay, Georgia rubber Grade B 140
The examples which follow illustrate the practice of the present invention.
Examples 1-V A series of composite friction element were prepared in which the amounts of the binder components, filler materials and aramid polymer fiber was varied. The various compositions of the composite friction materials are summarized in Table Ill below.
Table Ill
Examples
Percent by Weight
Binder Components I II //l IV V
GRS Synthetic Rubber 6.48 6.00 6.00 6.48 6.57
Sulphur 1.76 1.60 1.60 1.76 1.72
Litharge (PbO) 4.40 4.00 4.00 4.40
Cashew Polymer 2.96 2.72 2.72 2.96 2.99
Lead Powder 1.48 1.40 1.40 1.48
Carbon Black 0.80 0.72 0.72 0.80
Hexamethylene Tetranine 0.40 0.36 0.36 0.40 0.37
MgO 1.96 1.80 1.80 1.96 - ZnO - - - - 5.86
Total Bond 20.24 18.60 18.60 20.24 17.51 Examples Percent by Weight
Filler Materials I II //l IV V
Graphite-fine synthetic 6.80 7.00 7.00 6.80
Galena (PbS) 10.84 11.00 11.00 10.84
Cashew Resin-Solids 10.92 10.00 10.00 10.80 10.26
Calcined Kyanite (3Al203-2S102) 13.64 14.00 14.00 13.64 13.70
Calcined Petroleum Coke 6.04 6.40 6.40 6.04 6.18
White Iron Grit 22.88 23.00 23.00 22.88 23.07
Barytes (BaSO4) 3.76 8.20 6.40 3.76 7.47
Fused Aluminum Oxide - - 0.40 -
Ferrocene - - - 0.12 AluminaTrihydrate - - - - 11.72
Shale-Finely ground - - - - 8.30
Fiber
Aramid Polymer 4.88 1.80 3.20 4.88 1.79
(Kevlar 29)
100.00 100.00 100.00 100.00 100.00
The GRS rubber used in the examples was a 23% styrenebutadiene emulsion polymer.The "cashew polymer" used was a millable cashew nut shell oil liquid partially polymerized which was cross-linked with hexamethylene tetramine at controlled temperatures. The "cashew resin" was one sold as NC-300 by the Minnesota Mining and Manufacturing Co., this cashew resin is an 80% solution in toluene of a polymerized resin derived from cashew nut shell liquid having a viscosity at 25"0, of 10,000 to 18,000 cps and a gel time in minutes of from 20 to 55 at 830C. The calcined petroleum coke was National Carbon's W-8300 and the iron grit was Cleveland Metal Abrasive's G-1 20.
The ingredients of Examples I-V were compounded as follows:
The rubber component, which was in crumb form and the iron grit were soaked with toluene in a sealed container for 24 hours at about 1 500F and thereafter milled in a dispersion blade mixer. All of the remaining components except the aramid polymer fiber were added to the mixture in the container and the batch was mixed in a dispersion blade mixer and worked to a paste. The aramid polymer fiber was then added and the resulting product mixed thoroughly until uniform. This resulting mix was then passed through a hammer mill after which it was dried in an oven maintained at 1 500F (65"0) so as ta effect the complete removal of the toluene contained in the mixture but not to advance the binder materials beyond the flow point.
The resulting mixtures of Examples I-V were cold press formed into a performed briquette. The briquette was then molded into the shape of a brake shoe in a suitable mold for a period of one hour at 3500F (1 770C) and a pressure of 2500 pounds per square inch (1.76x 105 g/cm2) to cure and harden the mixture.
Brake shoes molded from the composite friction materials of Examples I-V were subjected to dynamometer and grade service (drag) tests in accordance with AAR (Association of American
Railroads) Test Specification M-926-72.
The dynamometer test subjects 3 randomly selected brake shoes to a sequence of light braking and heavy braking stops from speeds of 10-90 mph (16-145 kmh) in a prescribed sequence. The material lost during the stop tests is determined by weighing the shoes before and after the shoe
undergoes the braking sequence. In order for the shoe to be acceptable, the average of the
accumulated loss in volume of the 3 shoes must not exceed 1.2 cu. in. (19.66 cc) per shoe.
Drag tests measure the retarding forces produced by the test shoe which must exceed prescribed minimum requirements, e.g. in the light brake test, the requirement is that with a brake shoe load of 925 lbs.+25 Ibs., (419 Oil 1 kg) the minimum retarding force produced by the shoes must not be less than 300 Ibs., (136 Kg) and in the heavy brake test (1425 lbs.+25 Ibs (646 Kgll 1 Kg) load), the retarding force must not be less than 400 Ibs. (181 Kg).
The results of these tests are summarized in Table IV below.
Table IV
AAR Dynamometer Test AAR Drag Test
Material lost after Retarding Force
prescribed braking Light Heavy
Composite Friction sequence completed Braking Braking
Material of Example cu. in./shoe {cc/shoeJ Ibs (Kg) 04-15AI 0.63 (10.32) 310 (141) 370 (168)
05-22AII 0.46( 7.54) 300 (136) 390 (177) 05-25A III 0.33 ( 5.41) 300+(136+) 400+(181 +) -24A IV 0.31 ( 5.08) 300+(136+)400+(181+) -25A V 1.24(20.32) 300+(1 36+) 400+(1 +) It is seen from the foregoing examples that brake shoes made from an asbestos-free composition but with the inclusion of an aramid polymer fiber and a high absorptive filler have brake test results acceptable for railroad braking service.
For purposes of comparison, the procedure of Examples I-V were repeated with the exception that a fiber product other than an aramid polymer fiber was used in the preparation of the composite friction material. The compositions of the comparative composite materials designated by the symbol "C" are summarized in Table V below.
Table V
Comparative Friction Materials
C1 C2 C3 C4
Binder Components Percent by Weight
GRS Synthetic Rubber 5.58 6.12 6.08 5.62
Sulphur 1.67 1.84 1.65 1.53
Litharge (PbO) 4.19 4.59 4.13 3.81
Cashew Polymer 2.79 3.06 2.78 2.57
Lead Powder 1.40 1.53 1.39 1.28
Carbon black 0.74 0.82 0.75 0.69 Hexamethylenetetramine 0.37 0.41 0.38 0.35
MgO 1.86 2.04 1.84 1.70 Filler Materials
Graphite 6.4 - 6.38 5.89
Galena (PbS) 10.1 11.23 10.17 9.40
Cashew Resin Solids 10.3 7.84 10.24 9.47
Iron Grit 21.5 23.69 - 19.83 Barytes(BaSO4) 14.30 Mullite (Aluminum Silicate) 12.8 14.67 12.79 11.82
Petroleum Coke 5.6 6.15 5.67 5.24
Full Cured Cashew Nut Shell Liquid - 6.57 -
Fiber WollastoniteF-1 14.7 - - - Mica - 10.06 -
Cast Iron Fibers (2"x0.0005") - - 21.46
Fiberfrax (Aluminum Silicate) - - - 20.80
short staple fiber
Brake shoes molded from the composite friction materials of comparative compositions C1-C4 were subjected to the AAR dynamometer and grade service tests in accordance with the same procedures used to evaluate the brake shoes molded from the composite friction materials of Examples I-V. Brake shoes molded from the composite friction material C1 failed the AAR dynamometer test by not passing the 70 mph, 6000 lb. (113 kmh, 2722 Kg) B.S.I. stops.
Brake shoes molded from the C2 composite friction material passed the AAR dynamometer tests but wide fluctuations were encountered in the drag retardation tests and the friction material was of questionable physical strength based on the poor appearance of the shoe after the completion of the tests.
Brake shoes molded from the C3 composite friction material when tested by the AAR dynamometer test failed the drag test and were long on stops.
Brake shoes molded from the C4 composite friction material failed the AAR dynamometer test and had problems of blistering and spalling.
Claims (14)
1. A brake shoe characterised by a body of a composite friction material having a matrix comprises of a vulcanized rubber (as hereinbefore defined) binder material having distributed therethrough a plurality of filler particles including a hard mineral filler, a friction modifier, and a reinforcing fibre, at least one of the filler particles having an absorptive capacity and being present in a quantity sufficient for absorbing binder decomposed during braking, and the reinforcing fibre being a polymer characterised by recurring units of the formula
wherein Ar, is selected from p-phenylene, a chloro-substituted p-phenylene, and 4,4'-substituted diphenyl methane and Ar, is p-phenylene and the fibre being present in said body at a concentration of from 0.5 to 10.0 percent by weight.
2. The brake shoe of claim 1, wherein the absorptive filler has an oil absorption value (as hereinbefore defined) of at least 30 and is present in the body at a concentration of from 30 to 50 percent by weight).
3. The brake shoe of claim 1 or 2, wherein the hard mineral filler is selected from iron ore, iron grit, sand, fused silica and aluminium silicate.
4. The brake shoe of claim 1, 2 or 3, wherein the friction modifier is selected from graphite, partially cured cashew resin solids, lead and lead sulfide.
5. The brake shoe of any preceding claim, wherein the absorptive filler is selected from alumina trihydrate, BaSO4, ground shale, anthracite coal, magnesium oxide and clay.
6. The brake shoe of any preceding claim, wherein the polymer fibre comprises poly(p-phenylene diamine terephthalamide)-co-poly(4,4'-diamino diphenyl methane terephthalamide).
7. The brake shoe of any preceding claim, wherein the rubber binder is present in the composite friction body at a concentration of from 1 5 to 30 percent by weight; the hard mineral filler is present in the composite friction body at a concentration of from 15 to 30 percent by weight.
8. A brake shoe composition including a quantity of friction media, a quantity of a vulcanizable rubber (as hereinbefore defined) bond material, a quantity of synthetic reinforcing fibre formed from a polymer characterised by recurring units of the formula
where Ar, is selected from the p-phenylene, a chloro-substituted p-phenylene, and a 4,4'-substituted diphenyl methane and Ar2 is p-phenylene, a quantity of absorptive media, and a quantity of friction modifiers, the improvement therein comprising,
said friction media comprising hard mineral fillers
said bond material comprising a vulcanizable rubber (as hereinbefore defined) synthetic resin and curing agents to react therewith,
said synthetic reinforcing fibre being of a high strength, chemically inert, and high temperatureresistant and having physical characteristics of a tensile strength proximating 400,000 psi (28.1 2x 1 06g/cm2), elongation to break proximating 3 to 4 percent, tensile modulus proximating 8.5x 106 psi (5.97 x 108 g/cm2) and density proximating 0.052 Ib/in3 (1.44 g/cc), and thermal characteristics of decomposition at a temperature proximating 9300F (5000C) and a 40 percent decrease in tensile strength at 5000F (2600C), said fibre being present in a range by weight of 0.5 to 10.0 percent of the composition, and
said absorptive media comprising at least one filler having an oil absorption value (as hereinbefore defined) of at least 30 to absorb any of said bond decomposed during braking, said absorptive media being present in a range by weight of 25 to 50 percent of the composition.
9. A brake shoe composition as defined by claim 8, and further characterised by,
said quantity of said synthetic reinforcing fibre being further limited to a percentage range by weight of 1.8 to 4.88 percent.
10. A brake shoe composition as defined by claim 8 or 9, and further characterised by,
said hard mineral fillers selected from a group consisting of iron grit and calcined kyanite,
said bond material rubber being a styrene-butadiene emulsion polymer and said bond material synthetic resin being cashew polymer, and
said absorptive filler selected from the group consisting of barium sulfate, ground shale rock, alumina trihydrate and magnesium oxide.
11. A brake shoe composition as defined in any of claims 8 to 10, and further characterised by,
said hard mineral fillers being in an amount by weight proximating 37 percent,
said absorptive filler being in an amount by weight proximating 25 percent.
1 2. A brake shoe composition as defined in claim 8 or 9, and further characterised by,
said hard mineral fillers selected from the group consisting of iron grit, iron ore, sand, fused silica and calcined kyanite,
said bond material rubber being a styrene-butadiene emulsion polymer and said bond material synthetic resin being cashew polymer, and
said absorptive fillers selected from the group consisting of barium sulfate, alumina trihydrate, magnesium oxide, rotten stone, anthracite coal and clay.
13. A brake shoe composition as defined by claim 8 or 9, and further characterised by,
said hard mineral fillers being in a range by weight of 25 to 50 percent,
said bond being in a range by weight of 15 to 30 percent, and,
said friction modifiers being in a range by weight of 1 5 to 30 percent.
14. A brake shoe, substantially as hereinbefore described.
1 5. A brake shoe composition, substantially as hereinbefore described.
1 6. The features hereinbefore disclosed, or their equivalents, in any novel selection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8003745A GB2068978B (en) | 1980-02-05 | 1980-02-05 | Friction materials comprising rubber binder and aromatic polyamide fibres |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8003745A GB2068978B (en) | 1980-02-05 | 1980-02-05 | Friction materials comprising rubber binder and aromatic polyamide fibres |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2068978A true GB2068978A (en) | 1981-08-19 |
| GB2068978B GB2068978B (en) | 1983-09-07 |
Family
ID=10511117
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8003745A Expired GB2068978B (en) | 1980-02-05 | 1980-02-05 | Friction materials comprising rubber binder and aromatic polyamide fibres |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2068978B (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2532021A1 (en) * | 1982-08-23 | 1984-02-24 | Manville Service Corp | Composition for support plate for brake shoes |
| GB2129006A (en) * | 1982-10-21 | 1984-05-10 | Raymark Ind Inc | Composite fibre friction facing |
| EP0162684A2 (en) * | 1984-05-21 | 1985-11-27 | E.I. Du Pont De Nemours And Company | Fiber containing particulate elastomeric composition |
| DE3730430A1 (en) * | 1986-09-11 | 1988-03-24 | Toyota Motor Co Ltd | METHOD FOR PRODUCING A MOLDED FRICTION PART WHICH DOES NOT NEED A GRINDING PROCESS |
| FR2612588A1 (en) * | 1987-03-20 | 1988-09-23 | Journee Paul | Friction lining with surface passivation |
| WO1992005370A1 (en) * | 1990-09-14 | 1992-04-02 | Ferodo Limited | Improvements in or relating to brake pads |
| WO1992017715A1 (en) * | 1991-04-06 | 1992-10-15 | Ferodo Limited | Brake pad friction linings |
| US20140206808A1 (en) * | 2013-01-23 | 2014-07-24 | Vale S.A. | Composite material comprising uhmwpe and iron ore tailing and use of iron ore tailing in preparation of composite material |
-
1980
- 1980-02-05 GB GB8003745A patent/GB2068978B/en not_active Expired
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2532021A1 (en) * | 1982-08-23 | 1984-02-24 | Manville Service Corp | Composition for support plate for brake shoes |
| GB2129006A (en) * | 1982-10-21 | 1984-05-10 | Raymark Ind Inc | Composite fibre friction facing |
| EP0162684A2 (en) * | 1984-05-21 | 1985-11-27 | E.I. Du Pont De Nemours And Company | Fiber containing particulate elastomeric composition |
| EP0162684A3 (en) * | 1984-05-21 | 1986-10-01 | E.I. Du Pont De Nemours And Company | Fiber containing particulate elastomeric composition |
| DE3730430A1 (en) * | 1986-09-11 | 1988-03-24 | Toyota Motor Co Ltd | METHOD FOR PRODUCING A MOLDED FRICTION PART WHICH DOES NOT NEED A GRINDING PROCESS |
| FR2612588A1 (en) * | 1987-03-20 | 1988-09-23 | Journee Paul | Friction lining with surface passivation |
| WO1992005370A1 (en) * | 1990-09-14 | 1992-04-02 | Ferodo Limited | Improvements in or relating to brake pads |
| WO1992017715A1 (en) * | 1991-04-06 | 1992-10-15 | Ferodo Limited | Brake pad friction linings |
| AU648884B2 (en) * | 1991-04-06 | 1994-05-05 | Ferodo Limited | Brake pad friction linings |
| US5460250A (en) * | 1991-04-06 | 1995-10-24 | Ferodo Limited | Brake pad friction linings |
| US20140206808A1 (en) * | 2013-01-23 | 2014-07-24 | Vale S.A. | Composite material comprising uhmwpe and iron ore tailing and use of iron ore tailing in preparation of composite material |
| WO2014113854A1 (en) * | 2013-01-23 | 2014-07-31 | Vale S.A. | Composite material comprising uhmwpe and iron ore tailing and use of iron ore tailing in preparation of composite material |
| US9353242B2 (en) * | 2013-01-23 | 2016-05-31 | Vale S.A. | Composite material comprising UHMWPE and iron ore tailing and use of iron ore tailing in preparation of composite material |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2068978B (en) | 1983-09-07 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| PE20 | Patent expired after termination of 20 years |
Effective date: 20000204 |