NZ209973A - Lay flat hose reinforcement with multi-filament yarns and mono-filaments twisted together - Google Patents

Description

New Zealand Paient Spedficaiion for Paient Number £09973 209973 Priority Date(s): ., .t?9".

Complete Specification Filed: ^ Class: P. J. P.

TftWSw" Publicatson Date: ...

P.O. Journal, No: I ti.Z. PA'i^r.'TDrl-'Ce | 2 4 OCT 1984 I ■ I IIMI I ■!•««» «. -IML.W . . ■ I recent ~ NO DRAWINGS NEW ZEALAND PATENTS ACT, 1953 No.: Date: COMPLETE SPECIFICATION LAY-FLAT HOSE REINFORCEMENT 31/We, ANGUS FIRE ARMOUR LIMITED, a British Company of Bentham, Lancaster, LA2 7NZ, England hereby declare the invention for which i / we pray that a patent may be granted to iock/us, and the method by which it is to be performed, to be particularly described in and by the following statement: - - 1 - (followed by Page la) v:- I 209973 PP/JRM680 - l0_~ iflat Hooo Reinforoement This invention concerns lay-flat hose products, that is hoses which have a circular cross section when inflated with fluids, but which collapse into a flat configuration when pressure is released, enabling them 5 to be coiled, folded or flaked, etc., to ease handling and storage. Such hoses contain a lining, which is essentially impervious to the fluid they transport, they may also have an outer cover or coating and additionally comprise a textile reinforcement, which is 10 designed to meet the tensile, mechanical an£ pneumatic or hydraulic requirements of the hose when in operational use.

The invention particularly relates to this textile reinforcement and is not restricted to any type of lay-15 flat hose, nor to its method of construction or manufacture.

The textile reinforcement may be provided by various ways of assembling its component yarns, such as weaving, knitting, braiding, laying, etc. The 20 invention is not restricted to any of these methods of assembling the reinforcement, but particularly relates to textile assemblies of a woven construction.

In the case of woven textile assemblies, these contain warp yarns, which are disposed in an essentially 25 longitudinal direction along the hose length, and weft yarns which are disposed in a circumferential direction. In a textile reinforcement construction frequently used, the circumferential weft yarns are introduced by weaving on, for example, a circular 30 weaving machine. The weft yarns continuously pass round the hose circumference in spiral configuration , ;*12S£P1936Z$ ;// ;^ ' ":"T " V- I- 1 :••••'• • ;m ;209973 ;- 2 - ;interweaving with the longitudinal warp yarns to form a coherent tubular textile fabric. ;The amount of yarn in unit length of jacket is calculated to meet the mechanical requirements of the 5 hose, especially its tensile and pressure requirements. ;These together with the unit strengths of the yarns used determine the numbers of warp and weft yarns per unit area of hose jacket. To meet the requirements of higher strength yarns, required in hoses of larger 10 diameters, it is necessary to use yarns of higher thickness and weight. The weight of yarns is expressed as their decitex, which is defined as the weight of 10,000 m of yarns expressed in grams. In practice, it is found convenient to combine one or more 15 yarns of the standard decitex values, supplied by yarn manufacturers, by twisting or "plying" the yarns as a separate operation before weaving. By this technique, ;plied yarns for warp and weft can be made having individual yarn strengths and weights approaching 20 multiples of those of the individual yarns in the plies and, therefore, the number of plied warp yarns per centimetre of the hose circumference (warp density) ;can be restricted to a reasonable range. Similarly, the number of plied yarns per centimetre length of hose 25 (weft density), determined in the case of circular weaving by the number of passes of the shuttle per centimetre of hose jacket length (picks per centimetre), can be restricted to a reasonable range, ;whilst still giving the required strengths in the 30 circumferential direction. ;In the particular case of woven fabrics, the precise pattern of the yarns may also be varied in the weaving operation. Thus, for example, if the weft yarn alternately passes under and over successive 35 warps, a so called "plain weave" construction is produced. Alternatively, the warp changing mpohanism ^ ;f 2 SEP !9Sir ;■ ■■ \ ;>; S I ;;/ ;209973 ;r ;5 10 15 20 25 ;O ;30 ;o on the loom may be operated to allow the weft to pass over or under two or more warp yarns and then under or over the next warp yarn to produce so-called 'twill' construction, or even more complex patterning of the yarns can be made. Again, this application is not restricted to any specific fabric construction. ;Besides meeting the desired tensile and pressure requirements of finished hose, the nature of materials comprising the yarns, the decitex of warp and weft yarns, the number of yarns per centimetre, and the textile jacket construction, control other performance properties of hoses made from the reinforcing jackets. ;Thus, for example, the total warp strength of a hose is generally arranged to be greater than the weft strength, partly because the increase in warp density leads to better abrasion resistance in the final hose. ;Other properties, such as the tendency of the hose to elongate or shorten, or to swell when pressurised, or to kink, are also dependent on the yarns used, and on the precise construction of the hose jacket. These are well understood by those skilled in the art. ;The present invention relates to the twisted or plied yarns used to make jackets for hoses. Such yarns are multifilament yarns and are classified as continuous filament yarns, or staple yarns, and may be of synthetic (for example, polyamide, polyester, ;acrylic, viscose, PVA, aramide, etc.) or of natural (flax, cotton, wool, cellulose, for example) origin or they may be mixtures of these types. In the case of staple yarns, these are made by twisting the short fibres together to form a continuous yarn, as for example, in a spinning operation. The individual filaments which make the yarns generally have a decitex range between about 1 and 10 decitex, but these are combined together by twisting or intermingling during the manufacturing or spinning processes to form primarv fc >v • ;I2SEP19S&; ;309973 ;- t - ;yarns having many filaments in the individual yarn cross section therefore much higher decitexes. Thus for example, the yarns used for making lay-flat hoses of diameter range 5" to 10" are often based on primary yarns having a decitex range of 500-2,500 decitex, and may typically contain between 50 and 250 filaments in any cross section. In the case of multifilament yarns, a typical total decitex range is 800-1,200 decitex. ;As described above, plied yarns having multiples of this decitex are frequently used in both the warp and weft of hose reinforcement constructions. It may be desirable to have yarns of more than one chemical or physical type in a given hose jacket, either by using different yarn deniers, or different plies in the warp and weft, or by using yarns of different materials or plies between individual warp yarns, or by plying together yarns made from different materials to provide the plied yarns, used for warp and/or weft. ;Filaments of much thicker nature are also available, and are commonly called monofilaments. ;Their individual filaments ranging typically from about 100 to 3,000 decitex. Such monofilaments are commonly available from the extrusion of synthetic polymers such as polyamide, polyester. Our proposed use in hose does not restrict the material of manufacture. ;The present invention provides, in one aspect, a lay-flat hose comprising an inner lining and a textile reinforcing jacket, the said jacket containing at least some yarns which are composite yarns made by twisting one or more multifilament staple or continuous filament yarns together with one or more monofilaments. ;The hose may also include an outer covering. The jacket is preferably pre-formed, rather than formed in situ round an inner lining, and is preferably woven in seamless tubular form. The jacket is preferably, ;la' ;<> ^ —i' ;12SEPI9S2»n ;\ - ' " ■!, V i- ;209973 ;- 5 - ;though not necessarily, bonded to the inner lining and to any outer covering present, so as to prevent slippage between adjacent layers. ;In another aspect, the invention provides a method 5 of making a lay-flat hose which method comprises providing a textile reinforcing jacket, the said jacket containing at least some yarns which are composite yarns formed by twisting one or more multifilament staple or continuous filament yarns together with one 10 or more monofilaments, and providing an inner lining within, and bonding the inner lining to, the preformed jacket. Various techniques for providing inner linings within preformed reinforcement jackets, and for bonding inner linings to reinforcement jackets, are 15 well known in the art and will not be described here. ;The composite yarns may comprise different kinds of multifilament staple or continuous filament yarns twisted together with monofilament yarns. The composite yarns preferably contain up to 50% by weight, 20 particularly from 5% to 40% by weight, of monofilaments, the optimum depending on the internal diameter of the hose and on its tensile, hydraulic, pneumatic and other properties. ;It has not been common practice in the general 25 textile industry to make composite yarns by twisting together monofilaments with multifilament fine denier staple and continuous yarns. However, we have surprisingly found that by making such composite yarns, and using them to make the reinforcing textile jacket 30 for hoses, the final hose products acquire very considerable improvements in end performance, for example, in abrasion resistance. In this particular case, the substitution of composite monofilament and multifilament yarns for the multifilament yarns 35 commonly employed leads to a product of much enhanced performance. * f 2 SEP ISOiv";: /•' n - V- • v~v |. ... ■ v ^ 209973 On the other hand, the invention can be used to maintain standards of hose quality and performance, using reduced total yarn content per unit length of hose, thereby offering cost reduction, easier 5 manufacturing processes, or routes to combinations of properties which would otherwise be inaccessible, for example because the warp or weft spacing of the yarns would be too close for satisfactory weaving, or might give rise to hose products of, for example excessive 10 stiffness, poor kink performance, or poor ease of handling and coiling.

In woven reinforcement jackets, the composite yarns may be used as some or all of the warp yarns or of the weft yarns or of both warp and weft yarns. 15 In a preferred embodiment, all the weft yarns are composite yarns containing monofilaments. The improved abrasion resistance of the composite weft yarns enables the manufacturer to reduce the warp density by reducing the number and/or the thickness of 20 the warp yarns.

This is because the warp yarns to some extent protect the weft yarns from abrasion, and less protection is needed when the weft yarns themselves have improved abrasion resistance.

The following Examples illustrate the invention.

Example 1 A tubular reinforcement jacket of 6.7 cm diameter was woven using a plain weave. The warp yarns were composed of 334 multifilament polyester yarns twisted 30 together at 100 - 120 turns/metre and were of 3-ply 1,100 decitex. The weft yarns were composed of 6-ply 1,100 decitex polyester multifilament yarns twisted together at 20 turns/metre with two 300 decitex nylon monofilaments (0.37 mm diameter). A weft density of 35 4.33 picks/cm was used. An inner lining was formed inside the pre-formed jacket and bonded to the jaeke 6% 12SEPi9S£

Claims (1)

1. n n o 209973 - 7 - by steam heat. An outer coating was applied. Example 2 A tubular reinforcement jacket of 6.5 cm diameter was woven using a 2-1 twill weave. The warp yarns 5 were composed of 2 plies of 1,100 decitex multifilament polyester yarns twisted together at 140 turns/metre. 470 ends were used at two ends per mail. The weft yarns were composed of 6 plies of 1,100 decitex multifilament polyester yarn plus 2 plies of 0.37 mm 10 diameter monofilament twisted together at 60 turns/metre. The cover jacket had 5 weft picks per cm. An inner lining of EPDM rubber coated on the outside with hot melt adhesive was inserted into the jacket and bonded to it by passing steam through the interior of the 15 lining. ,f2SEP15S4S 1 . f 209973 - 8 - ettTMS WHAT tfVJE CLAIM IS: A lay-flat hose comprising an inner lining and a textile reinforcing jacket, the said jacket containing at least some yarns which are composite yarns made by twisting one or more multifilament staple or continuous filament yarns together with one or more monofilaments. A lay-flat hose as claimed in claim 1, wherein said textile reinforcing jacket is of a woven construction comprising warp yarns and weft yarns. A lay-flat hose as claimed in claim 2, wherein all of said weft yarns are composite yarns containing monofilaments. A lay-flat hose as claimed in any one of the preceding claims, wherein said composite yarns contain up to 50% by weight of monofilaments. A lay-flat hose as claimed in any one of the preceding claims, wherein said composite yarns contain from 5% to 40% by weight of monofilaments. A lay-flat hose as claimed in any one of the preceding claims, wherein the hose is provided with an outer covering. A lay-flat hose as claimed in any one of the preceding claims, wherein said textile reinforcing jacket is pre-formed. A lay-flat hose as claimed in any one of the preceding claims, wherein said textile reinforcing jacket is woven in seamless tubular form. A lay-flat hose as claimed in any one of the preceding claims, wherein said textile reinforcing jacket is bonded to said inner lining and to any outer covering present. A lay-flat hose as claimed in claim 1 and substantially as hereinbefore described. 209973 9 11. A method of making the lay-flat hose of any one of the preceding claims, which method comprises providing a textile reinforcing jacket, the said jacket containing at least some yarns which are composite yarns formed by twisting one or more multifilament staple or continuous filament yarns together with one or more monofilaments, and providing an inner lining within, and bonding the inner lining to, the preformed jacket. 12. A method as claimed in claim 11 and substantially as hereinbefore described.