一层或多层非金属燃料系统管

[中文适用范围]： 该 SAE 标准涵盖了作为用于汽油、酒精与汽油的混合物或柴油燃料系统的液体承载或蒸汽承载组件制造的多层非金属管材的最低要求。本文件还涵盖单壁管（一层结构）。该结构的壁上有一层或多层聚合物基化合物，主要目的是提高对各种燃料中碳氢化合物的渗透阻力。该结构可以具有直壁构造或者可以具有部分盘旋或波纹状的壁。它可以具有具有改进的导电性的最内层，用于需要这种特性的地方；此外，如果管道是单壁的，则改进的导电性可以适用于整个壁结构。本文件旨在涵盖在 -40 摄氏度以上和 115 摄氏度以下运行且最大工作表压高达 690 kPa 的燃油系统任何部分的管道。峰值间歇温度为 115 摄氏度。对于长期连续使用，温度不得超过 90 摄氏度。在某些情况下，适用于输送液体燃料的管材与用于输送液体燃料的管材的标准有所区别。携带燃油蒸气。术语“燃料蒸气”也适用于蒸发排放，是指燃料成分呈蒸气形式（浓度非常低）且在不超过 17 kPa 的工作表压下运行的情况。燃料蒸气或蒸发排放物可能含有少量液体燃料，这些液体燃料主要由于蒸气冷凝而存在。 [外文原描述]： This SAE Standard presents the minimum requirements for nonmetallic tubing with one or more layers manufactured for use as liquid-carrying or vapor-carrying component in fuel systems for gasoline, or alcohol blends with gasoline. Requirements in this document also apply to monowall tubing (one layer construction). When the construction has one or more layers of polymer-based compounds in the wall, the multilayer constructions are primarily for the purpose of improvement in permeation resistance to hydrocarbons found in various fuels. The tube construction can have a straight-wall configuration, a wall that is convoluted or corrugated, or a combination of each. It may have an innermost layer with improved electrical conductivity for use where such a characteristic is desired. The improved electrical conductivity can apply to the entire wall construction, if the tubing is a monowall. (For elastomeric based MLT constructions, refer to SAE J30 and SAE J2405).Unless otherwise agreed to by suppliers and users this document applies to tubing for any portion of the fuel system that might operate continuously at temperatures above −40 °C and below 90 °C and up to a maximum working gage pressure of 450kPa. The tubing can be used at the peak intermittent temperature up to 115 °C.This document can apply to systems that operate at higher pressures and/or are exposed to higher temperatures. For higher pressures, the acceptance criteria of section 7.2 must be correspondingly changed. For higher temperatures, the acceptance criteria of sections 7.2 and 7.14 remain the same, but apply at the higher temperature. The selection of higher temperatures and pressures that could be used for this document would be the decision of the end user and supplier of the specific fuel/fuel vapor system in question.There are three types of tubing covered by this specification, based on the type of application for which the tubing is intended to be used:High pressure, liquid fuel line is tubing that handles liquid fuel at pressures up to 450 kPa pressure, and can handle the maximum pressure requirements identified in sections 7.1 and 7.2 . These are typically the smaller diameter tubes identified in Table A1 .Low pressure, liquid fuel line is tubing that is regularly exposed to liquid fuel, but is subjected to pressures that are under 50 kPa (e.g. fuel filler pipes). These are typically the larger diameters identified in Table A1 .Fuel vapor tubing is tubing that handles fuel in vapor form or some liquid condensed from vapor, and operates at a working gauge pressure that does not exceed 20 kPa.In some cases, a distinction is made in the criteria that apply to tubing used to carry liquid fuel compared to tubing used to carry fuel vapor. These are identified separately in each section.Cross Reference: ASTMD4000,ASTMD4066,ASTMD412,ISO4639-3,ISO527,J1645_201909,J1681_202305,J1737_201908,J1960,J2027,J2044,J2045,J30_202205