建筑排水管道系统防污染用塑料止回阀 Plastic check valves for anti-pollution for discharge piping systems inside buildings  ICS  83.140.30 CCS  G 33   中华人民共和国国家标准 GB/T 44574—2024 2024-09-2 9发布 2025-04-0 1实施     国家市场监督管理总局 国家标准化管理委员会 发 布 目　　次 前言   ·····································································································   Ⅲ 1     范围   ··································································································   1 2     规范性引用文件   ······················································································   1 3     术语和定义、符号和缩略语   ··········································································   1      3.1     术语和定义   ······················································································   1      3.2     符号和缩略语   ····················································································   2 4     材料   ··································································································   2 5     设计   ··································································································   3 6     要求   ··································································································   3      6.1     外观   ······························································································   3      6.2     颜色   ······························································································   3      6.3     规格尺寸   ·························································································   3      6.4     性能要求   ·························································································   4      6.5     铅限量   ···························································································   5 7     试验方法   ······························································································   5      7.1     状态调节   ·························································································   5      7.2     外观和颜色   ······················································································   5      7.3     尺寸   ······························································································   5      7.4     密度   ······························································································   5      7.5     维卡软化温度   ····················································································   5      7.6     熔体质量流动速率变化率   ········································································   5      7.7     氧化诱导时间   ····················································································   6      7.8     烘箱试验   ·························································································   6      7.9     坠落试验   ·························································································   6      7.10     流通能力   ························································································   6      7.11     水密性   ··························································································   6      7.12     铅限量   ··························································································   6 8     检验规则   ······························································································   7      8.1     检验分类   ·························································································   7      8.2     组批和分组   ······················································································   7      8.3     出厂检验   ·························································································   7      8.4     型式检验   ·························································································   8      8.5     判定规则   ·························································································   8 9     标志、包装、运输、贮存   ···························