MXPA99000741A - Hose and method for wear detection - Google Patents

Abstract

The present invention indicates excessive wear on the outer cover of a hose in order to help avoid unexpected ruptures and spills. The invention is a hose with an outer cover. The outer cover has two layers made of rubber or plastic. The outer cover has an inner layer of one color (e.g. yellow) and an outer layer of another color (e.g. black). When the outer cover wears down to expose color of the inner layer, the end user is made aware that outer cover wear is approaching the reinforcement layer and that the hose should be replaced.

Description

HAN? UERA AND METHOD FOR DETECTION OF ROUGHING FIELD OF THE ART This invention relates to manqueras. The invention also relates to a method for detecting the existence of wear on the outer casing of the hose. BACKGROUND OF THE ART Industrial and commercial uses often involve pulling the hoses on uneven concrete floors and roads. A disadvantage of hoses of the prior art is that substantial wear, approaching the point of rupture, is not immediately evident upon subjecting the hose to a superficial visual inspection. Therefore, the user of the hose is often surprised by not having a useful hose, and therefore can not avoid the unexpected formation of spills. The abrasion resistance of the outer casing of rubber hoses is becoming an environmental problem more and more. In the case of hydraulic hoses that have a textile or wire reinforcement, corrosion of the wire or abrasion of the fabric soon follows the wear of the outer wrapper. Once this phenomenon occurs, the hose will fail. PRESENTATION OF THE INVENTION The present invention indicates excessive wear of the external surface of a hose in order to avoid unexpected spills and spills and a life expectancy of the hose. The invention is a hose with a coextruded cover or applied as a layer. The outer cover has an inner layer of one color (for example yellow) and an outer layer of another color (for example black). When the outer cover wears out to expose the yellow coat, the end user realizes that hose wear is approaching the reinforcement layer which results in reduced life of the sleeve. A simple abrasion test shows that a strong contrast in color provides an early warning hose. Prior art hoses employing a transparent or translucent color in one layer do not provide sufficiently strong contrast. In addition, the colors of the prior art are incorporated to detect internal leaks and not external wear. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view, partially cut away, illustrating the hose of the invention. Figure 2 is the hose of the fiqura i with several layers of reinforcement. PREFERRED MODE OF THE INVENTION Figure 1 shows a sleeve 10 of the present invention. The hose 10 as a layer structure Multiples comprising an outer layer 1 and an inner layer 16. The outer layer 14 and the inner layer 16 lupst have the outer cover 18 of the sleeve 10. In other embodiments, the sleeve 10 may include a reinforcement layer 20. an intermediate layer 22 or both layers 20 and Figure 2 shows hose 10 with several intermediate layers 22. Intermediate layer 24 typically separates all reinforcement layers. A hose according to the present invention comprises an outer covering consisting essentially of an outer layer of opaque color and an internal layer of opaque color where the layers have different colors and where the abrasion of the outer layer shows the color of the layer internal therefore acting as an indicator of wear of the outer cover. The combination of colons is a system of early warning to detect the disqualification of the outer cover. The color exposure of the inner layer in this way is a visual indicator of external wear due to abrasion of the hose. The materials and the construction of the hose are critical aspects. This invention can be applied to a wide variety of materials and hose constructions. For example, this invention can be employed with hoses which are simple, such as, for example, the hoses described in FIG. he solitaire de paienití Narteamepcana serial number 08 / 512,846 presented on d &; August 9, 1995. Said invention can also be used with a wide variety of available thermosetting hose hoses. See U.S. Patent No. 5,356,681 and 5, 88,974. Layers 14, 16, 22 and 24 may vary widely and may also be a thermoplastic alternating shell (TPUI) with uniunal properties and conventional Lermoepdureable rubber performance, but with the processing characteristics of a thermoplastic material. The outer layer 14, the inner layer 16 and the intermediate layers 22 and 24 can also be a sturdy rubber. The thermosetting rubbers in the layers 14, 16 and 22 can vary widely and can be any natural or synthetic rubber-Typically , the e < terna 14 It has a thickness that has been solved only by Dr. Txxca considerations. In general, however, the outer layer 14 has a thickness that lies within a range of 0.030 inch to 0.250 inch. Preferably, the thickness is within a range of 0.030 to 0.100 inch. The reinforcement layer 20 varies ampl amen e. It is formed by the train of natural fibers, fibers s ni. txc.as or b on metallic wires cos. The unethical f bras can be glass fibers, polyester fibers, Kevlar (MR) fibers or Novex (MR) fibers. The metal fibers are usually steel fibers. Frequently, the reinforcement layer 20 is a fabric of textile material. Typically, the reinforcing fabric is wrapped in a skewed manner prior to the application of the outer cover 18. In another embodiment, a reinforcement layer 2G ~ may be a helically wound spiral wire. A combination for the reinforcement layer 20 is the use of a reinforcing fabric with a spiral wire on the fabric below the outer cover. The intermediate layer 22 is formed by extrusion in such a way that it has a thickness of 0.005 to 0.25, preferably from 0.001 to 0.1 inch. After the extrusion mold of the innermost layer 22, a fibrous reinforcement layer 20 wrapped in a braided or spiral manner is provided and then an outer layer 18 on the innermost layer 22. The reinforcement layer 20 can also be a helical strand of rolled wire. In the case of the fibrous reinforcement layer and the outer layer, any conventional material can be used. The composite flexible hose of the present invention can be obtained by forming, on the innermost layer, the intermediate rubber layer, the layer fiber reinforcement and the external rubber layer, and then by vulcanization. The vulcanization is preferably carried out under vapor pressure conditions of from 4 to 5.5 kgf / cm2 and a temperature of about 150 to 160 ° C. The method of the present invention for detecting external wear on the hose cover 18 comprises the steps of submitting a hose having an inner layer 16 of an opaque color and an outer layer 14 of a different opaque color and by abrading the outer layer to make the color of the inner layer appear. The fact of observing the color of the inner layer indicates wear of the outer cover. The color of the inner layer is an early warning system to detect the wear of the outer cover. The opaque colors used vary widely. Preferably, layer 14 is black and layer 16 yellow. Combinations of black and blue are also used. The greater the contrast between the -colors, the easier the detection of wear. While transparent to translucent colors may be used, they do not usually provide the contrast necessary for early detection. The methods for manufacturing the present hose assembly 10 are well known in the art. A particular well-known method includes a two-part extrusion process known as "crosshead" extrusion. The method "Crosshead" extrusion typically includes first extruding an inner layer 22, and then extruding an outer layer 18 there. Co-trusion methods can also be applied. As is known in the art, coextrusion methods include the use of two extruders at the same time, forming this way. both the inner layer and the C? P? externally simultaneously. The extrusion is also preferably used to form the outer shell. 18 A firm bond must be established between the layers 14 and 16. In this regard, a method for producing a two-layer cover 18 is extrusion if either of the inner layer and the outer layer. This method employs two sets of extruders combined in such a way that they share an assembly set. of extrusion dies having two annular holes arranged concentrically. One of the extrusion machines is connected to the internal orifice of the given mine, as the other extruder is connected to the external orifice of the die. The two extruders are operated simultane- ously in such a way that the inner and outer layers come into contact between them after both types of pipes are in a plastic state and are not yet exposed to the atmosphere. It is efficient and has the advantage of being able to provide a reliable and reliable link between the two layers 14 and 16.

Even though the simultaneous extrusion method described above is the preferred method, the two-layer rubber can also be produced by a familiar two-step extrusion method. In this case, the inner layer is formed by an ordinary extrusion technique in a first stage, and then the outer part of the inner layer can be covered with a thin layer of adhesive, which may be rubber. Then, the outer layer of the core is processed. A processing by stage to good extrusion can be used for all the layers and can be used both for thermoplastic hoses and for thermosetting hoses. In another embodiment, the layer 16 of the outer cover 18 can be wrapped instead of extruded. The envelope of the sp. 16 usually occurs directly before the crosshead of the extruder which extrudes the outer cover layer 14. In the following examples, the layer 22 was first extruded and then the reinforcement layer 20 was wrapped around it. of the layer 22. The layer 20 was a wire braid and the layer 22 a tei moistening rubber. Then, the layer 16 was wrapped on the layer 20 and then the layer 14 was extruded on the layer 16. 14 and 16 were of terpeneous rubber, but each had a different opaque color.

A hose of the following structure was prepared. The ds type hose was SAE 100R2; a hydraulic hose covered with rubber, reinforced with steel wire, high pressure. The outer layer 14 was a blue rubber cover. The inner layer 16 was a wear layer of yellow heat rubber. The reinforcement layer 20 was one. braid of wire. Layer 22 was a black inner tube. The simple abrasion weathered the blue outer layer 14 and showed the yellow layer 16 after approximately! 1000 abrasion cycles. The fact of seeing the yellow layer 16 after 1000 cycles is an early indicator of wear and the hose must be replaced at this time »The cycles were carried out at a high temperature of approximately 73 ° F. The blue cover 14 it had a thickness of 0.025 inch and the yellow layer 16 had a thickness of 0.015 inch. The cycles were carried out in accordance with ISO 6945: 1991 (E) p opposite. Example II Our hose additives of example I were tested. In each test 4 different sections of the hose were subjected to abrasion. THE RESULTS TO a.r &. (^ N below.) HOSE 1 SECTION NUMBER Time Cycles? - Observations. 0925 O Ambient temperature 73"F 0932 715 Yellow color layer visible. 0933 768 < Visible wire 0938 1057 Visible wire. 0945 1449 Yellow color layer visible.

HANDLE 2 SECTION NUMBER Time Cycles 1 2 3 4 Observations. 0950 O Ambient temperature. 73 ° F. 1000 587 X Visible yellow color layer »1004 837 X Visible wire» 1003 1055 X Visible wire. 1010 1188 X Visible yellow color layer »Again, the data shows that the yellow indicator layer 16 functions as an early indicator of wear. The exposure of the color layer 16 is an initial indicator of hose wear. The exposure of the wire or the Reinforced layer 20 of the hose indicates the presence of ur.a fails. You must replace the hose in this breast.

Claims (1)

1. REI I HO? CACIDnlEB i. A hose comprising an outer shell consisting essentially of an outer layer of opaque color and an inner layer of opaque color "wherein the layers have different colors and where the abrasion of the outer layer shows the color of the inner layer thus acting as a coater. or external wear indicator - 2, A hose comprising an outer shell QU.IS consists essentially of an external layer of opaque color and of an internal layer of opaque color, where the layers have different heats and where the combination of heats is an early warning system to detect the wear of the outer cover. 3, A hose comprising U ?? hose having an internal layer of an opaque color and an outer layer of an opaque color d, where the exposure of the color of the inner layer is a visual indicator of abrasion wear of the hose. 4, A hose according to claim 1, comprising an internal tubu in addition to the outer cover. 5, A hose of goodness with the claim 4, comprising a recess layer between the tuba in tei no and the outer sheath, 6, U? T, m & ns &rs. in accordance with claim 1, where the outer shell layers consist essentially of a thermosetting rubber rubber. A hose according to claim 1, wherein the layers of the outer shell consist essentially of a thermoplastic. 8 »A hose according to claim 1, comprising an outer shell made of a hose, comprising the steps of adding a hose having an outer layer of an inner layer. of an opaque color and a third layer of a different opaque heat and subjecting the outer layer to abrasion so that the color of the inner layer appears, a method according to claim 8 results from the observation of the Heat from the inner layer indicates wear on the outer cover. Item. A method according to claim 8, wherein the. Observation of the color of the inner layer is an early warning system for detecting the wear of the outer cover. 12. An etod according to claim 8, comprising the coefficient step of the inner layer and the layer. external in order to form the outer cover. 13. A method according to claim 8, comprising the steps of wrapping the inner layer of the outer cover and extruding the outer layer on the inner layer wrapped in order to form the outer cover »14. A method according to claim 8, which tzap \ pr & r \ d & the steps of extruding the inner layer first and then extruding the outer layer on the inner layer in order to form the outer shell.