RU2285855C1 - Fuel hose - Google Patents

Abstract

FIELD: engine engineering.

SUBSTANCE: fuel hose comprises inner chamber made of rubber based on the fluoroelastomer and intermediate and outer layers made of rubber on the basis of epichlorohydrin rubber. The hose is additionally provided with the layer of fluorine-containing latex of 0.1-0.3 mm in thickness that is applied on the outer layer of rubber made of epichlorohydrin rubber.

EFFECT: enhanced reliability.

2 tbl

Description

The invention relates to the development of hoses with reduced fuel permeability, designed to supply fuel through pipelines of gasoline engines with an electronic fuel injection control system, and can be used in the manufacture of rubber products for the automotive industry.

Fuel hoses with high interlayer adhesion are known made of heat-oil-resistant fluororubber (inner layer) and ethylene-vinyl acetate copolymer (outer layer). For the inner layer, use a rubber mixture composition, parts by weight: Dai-el G703 rubber (contains a diol curing system) (100), calcium hydroxide (5), carbon black (15), and for the outer layer, a butyl acrylate copolymer, ethylene, 2 -methoxyethyl acrylate and vinyl acetate (15: 10: 50: 25) with 4 parts by weight guanidine vulcanizing agent. Laminated tubes from these mixtures are obtained by co-extrusion, followed by braiding with polyester fiber (Pat. 61-171981, Japan (1986) (CA, 1986, V.105, 228338).

The technology of manufacturing two-layer gas-resistant hoses with an inner layer of fluororubber and an outer layer of epichlorohydrin or chloroprene rubber is described (Pat. 5356681, USA (1984) (RLC, 1997, 1U47P). Multilayer rubbers are obtained by co-extrusion of fluorinated rubber mixtures (inner layer) and based on nitrile butadiene rubber (less than 37% acrylonitrile) with silicon dioxide (outer layer), braid and subsequent vulcanization (Application 01-247157, Japan (1989) (CA. 1990, V.112, 100517), see review , author: Nudelman Z.N., Rubber and rubber, No. 1, 2001, p.31-42.

Similar examples of hoses are described in patents: DE 3821723, C1, 09.21.1989, DE 3510395, A1, 09.25.1986, DE 3715251, A1, 12/01/1988, however, their use according to the EURO-3 standard (TU 305-57-089- 99 - fuel leakage is not more than 2.5 g / m ^2/24 hours with the "blank" sample) is problematic, since their main destination - a standard Euro-2 (TS 2556-002-12212865-99 - fuel leakage is not more than 50 g / m ^2/24 hours exclude "blank" sample).

It is known to use fluororubber latexes for producing films as a binder for impregnating asbestos fibers.

The composition of films based on LD-242 latex from fluorine rubber Vaiton A includes (including 100 parts by weight of rubber):

latex LD-242 - 100, ZnO - 10, blankfix - 10, nonionic surfactant - 3,

vulcanizing agent LD-214 (bis-cinnamilidenehexamethylenediimine) - 2 (see Galil-Ogly F.A., Novikov A.S., Nudelman Z.N. Fluorine rubbers and rubbers based on them. M: Chemistry, 1966. - c .218). Films are mainly used for coating fabrics and metals.

Closest to the claimed method is a sleeve for fuel systems of automobile engines, which includes an inner layer of fluororubber and an intermediate and outer layer of epichlorohydrin rubber (Patent No. 2235245, BI No. 24, 2004, prototype).

The disadvantage of the prototype is the high fuel permeability of the hose (sleeve) and its unsatisfactory stability in weight over time (the floating value of the "empty" (unfilled with fuel) sample for control according to TU 2556-119-00149289-2001). The stability in weight over time of a hose sample which is not filled with fuel is necessary for reliable determination of its fuel permeability according to TU 2556-119-00149289-2001, according to which the weight of the "empty" sample is not taken into account.

The aim of the invention is to achieve low fuel permeability of the hose.

This goal is achieved by applying an aqueous solution of fluorine-containing latex to the surface of the hose.

The invention consists in applying to a fuel hose comprising an inner chamber of rubber based on fluoroelastomer and an intermediate and outer layer of rubber based on epichlorohydrin rubber, a layer of fluorine-containing latex with a thickness of 0.1 ... 0.3 mm at a flow rate of 0.2 .. .0.6 kg / m ² at a drying temperature of 110 ... 130 ° C. In this case, a decrease in fuel permeability of 1.8 ... 1.9 times is achieved.

Example 1. Obtaining a solution for lubricating the fuel hose.

2000 g of SKF-26I latex with a rubber concentration of 40% (TU 6-05-041-352) and 200 g of deionized water are placed in a container. Hexamethylenediamine carbamate 1.8 ... 2.0 parts by weight is used as a hardener. for 100 hours in terms of rubber. Filler - zinc white BTsO (GOST 202-84) in a concentration of 15 ... 18 parts by hour for 100 hours rubber. The solution is applied to the surface of the fuel hose with a brush, dipping or spraying in two or three layers (thickness 0.1 ... 0.3 mm). Then dried with hot air. Drying temperature 120 ± 10 ° C with a flow rate of latex of 0.2 ... 0.6 kg / m ² at the stage of processing of the hose.

Example 2. Testing fuel hoses

Laboratory testing of prototypes of hoses for compliance with the requirements of TU 2556-119-00149289-2001 and TU 305-57-089-99 in terms of fuel permeability at a temperature of 23 ± 2 ° C was carried out on parts 2123-1101079-20 "Ventilation hose of the fuel tank and bulk pipe. " Norm TU 2556-119-00149289-2001 not more than 5.0 g / m ^2/24 hours exclude "blank" sample rate for the TU 305-57-089-99 not more than 2.5 g / m ^2/24 hours taking into account the "idle" sample, the EURO-3 standard.

The test results of the prototype hose are shown in table 1, and the fuel hose coated with a layer of fluoratex in table 2. For clarity, the experiment took hoses that do not pass on both TUs: 2556-119-00149289-2001 and 305-57-089-99, respectively.

Table 1
Fuel permeability for ШЛ 7.94 × 14.29 hose, not passing through the technical specifications for EURO-3 (prototype) No day The mass of the "blank" sample, m (cold), g Daily weight loss, Δm (cold), g Toplivopronitsaemost "blank" sample, T, g / m ^2/24 hours The mass of the sample with fuel, m (t), g Daily weight loss, taking into account "idle", Δm, g The difference in losses, Δm-Δm (cold), g Toplivopronitsaemost with the "idle" sample, T, g / m ^2/24 hours Toplivopronitsaemost exclude "blank" sample, T, g / m ^2/24 hours one 110.14 116.11 2 110.08 -0.06 9.2 116.07 -0.04 +0.02 - 6.1 3 110.02 -0.06 9.2 116.02 -0.05 +0.01 - 7.7 four 109.97 -0.05 7.7 115.97 -0.05 0 0 7.7 5 109.94 -0.03 4.6 115.95 -0.02 +0.01 - 3,1 6 109.89 -0.05 7.7 115.91 -0.04 +0.01 - 6.1 7 109.86 -0.03 4.6 115.87 -0.04 -0.01 1,5 6.1 8 109.82 -0.04 6.1 115.84 -0.03 +0.01 - 4.6 9 109.78 -0.04 6.1 115.80 -0.04 0 - 6.1 10 109.74 -0.04 6.1 115.74 -0.06 -0.02 3,1 9.2 eleven 109.70 -0.04 6.1 115.69 -0.05 -0.01 1,5 7.7 12 109.67 -0.03 4.6 115.65 -0.04 -0.01 1,5 6.1 13 109.64 -0.03 4.6 115.60 -0.05 -0.02 3,1 7.7 fourteen 109.61 -0.03 4.6 115.56 -0.04 -0.01 1,5 6.1 Note: effective hose length, l (eff.) = 261.92 mm;
inner diameter, d = 7.94 mm;
area, S = 0.00653 m ² ;
Δm = -Δ (m (i + 1) -m (i)).

table 2
Fuel permeability for the inventive hoses ШЛ 7.94 × 14.29 (fluoratex coating) No day The mass of the "blank" sample, m (cold), g Daily loss of mass, Δm (cold), g Toplivopronitsaemost "blank" sample, T, g / m ^2/24 hours The mass of the sample with fuel, m (t), g Daily weight loss given
idle, Δm, g The difference in losses, Δm-Δm (cold), g Toplivopronitsaemost with the "idle" sample, T, g / m ^2/24 hours Toplivopronitsaemost exclude "blank" sample, T, g / m ^2/24 hours one 107.67 113.69 2 107.67 0 0 113.69 +0.01 +0.01 - 3 107.67 0 0 113.69 -0.01 -0.01 1,6 1,6 four 107.67 0 0 113.69 0 0 - - 5 107.68 +0.01 0 113.69 +0.01 0 - - 6 107.68 0 0 113.69 0 0 - - 7 107.69 +0.01 0 113.69 +0.01 0 - - 8 107.70 +0.01 1,6 113.69 +0.01 +0.02 - - 9 109.70 0 0 113.69 0 0 - - 10 107.70 0 0 113.69 0 0 - - eleven 107.69 -0.01 1,6 113.69 -0.01 0 - - 12 107.70 +0.01 0 113.69 +0.01 0 - - 13 107.70 0 0 113.69 0 0 - - fourteen 107.69 -0.01 1,6 113.69 -0.01 0 - - Note: effective hose length, l (eff.) = 255.90 mm;
inner diameter, d = 7.94 mm;
area, S = 0.00638 m ² ;
Δm = -Δ (m (i + 1) -m (i)).

Claims (1)

A fuel hose comprising an inner chamber of rubber based on fluoroelastomer and an intermediate and outer layer of rubber based on epichlorohydrin rubber, characterized in that it further comprises a layer of fluorine-containing latex of 0.1-0.3 mm thickness on the surface of the outer layer of rubber made of epichlorohydrin rubber .