JB/T 51239-1999
Disc Harrow Blade - Product Quality Grading (Internal Use)
圆盘耙片 产品质量分等（内部使用）
Catalogue
前言 → 1 范围 → 2 引用标准 → 3 质量指标 → 4 试验方法 → 5 检验规则 → 6 评定原则 Foreword → 1 Scope → 2 Normative References → 3 Quality Indicators → 4 Test Methods → 5 Inspection Rules → 6 Evaluation Principles
Scope
This standard specifies the quality indicators, test methods, and inspection rules for two product grades of disc harrow blades: qualified product and first-grade product. This standard applies to the quality grading of disc harrow blades (hereinafter referred to as blades).
本标准规定了圆盘耙片合格品、一等品两个产品等级的质量指标、试验方法和检验规则。本标准适用于圆盘耙片（以下简称耙片）产品的质量分等。
Normative References
Keywords
Application Summary AI generated
Manufacturers and quality inspection agencies use this standard to grade disc harrow blades into qualified or first-grade levels. It matters because it sets clear benchmarks for hardness, metallographic structure, and edge defects, ensuring reliable and durable performance in agricultural machinery.
圆盘耙片制造商和质检机构使用本标准来对产品进行质量分等，确保产品达到合格品或一等品要求。本标准通过明确硬度、金相组织、刃口残缺等关键指标，帮助提升圆盘耙片的整体质量水平，保障农业机械作业的可靠性和耐久性。
AI Summary AI generated
This standard specifies quality indicators, test methods, and inspection rules for qualified and first-grade disc harrow blades. Blades must be made of 65Mn steel and heat-treated to 38~48 HRC. Key indicators include hardness pass rate, metallographic structure, edge defects, surface profile, flatness, runout, and coaxiality. Test methods detail hardness measurement and metallographic analysis. Inspection follows GB/T 2828 sampling, with nonconformities classified into A, B, and C categories for grading.
本标准规定了圆盘耙片合格品和一等品的质量指标、试验方法和检验规则。耙片须用65Mn钢板制造，热处理后硬度38~48 HRC。质量指标包括硬度点合格率、金相组织、刃口残缺、面轮廓度、平面度、跳动和同轴度。试验方法详细说明了硬度检测和金相分析步骤。检验规则采用GB/T 2828抽样，按A、B、C类不合格项评定产品等级。
Key Sentences extracted from text
本标准规定了圆盘耙片合格品、一等品两个产品等级的质量指标、试验方法和检验规则。
耙片应采用性能不低于GB/T 699、GB/T 710、GB/T 711 中规定的65 Mn 钢板制造。
耙片应进行热处理，其硬度为38~48 HRC。
按圆盘耙片产品的技术水平和质量水平，分为一等品和合格品。
采用逐项考核，按项目定等，以不合格分类表中各组达到的最低等级定为产品等级。
This standard specifies the quality indicators, test methods, and inspection rules for two product grades of disc harrow blades: qualified product and first-grade product.
Blades shall be manufactured using 65 Mn steel plate with performance not lower than that specified in GB/T 699, GB/T 710, and GB/T 711.
Blades shall undergo heat treatment, with a hardness of 38~48 HRC.
According to the technical level and quality level of disc harrow blade products, they are divided into first-grade and qualified products.
Adopt item-by-item assessment, grade by item, and take the lowest grade reached by each group in the nonconformity classification table as the product grade.
Standard Timeline
Changes from replaced version:
- 对耙片的性能指标进行了修改
- Modified the performance indicators of the blades