Overview
Weights are fundamental tools in metrology, serving as reference masses for calibrating weighing instruments such as analytical balances, platform scales, and industrial weighbridges. Their accuracy is critical in sectors like pharmaceuticals, jewelry, and logistics. Standardized by organizations like OIML (International Organization of Legal Metrology) and ASTM, weights are classified into accuracy classes (e.g., E1–M3), with E1 being the most precise. Modern weights often feature anti-magnetic and wear-resistant coatings to maintain integrity over time. Historically, weights evolved from stone or metal artifacts to today’s precision-engineered pieces. Legal metrology regulations mandate periodic recalibration to ensure compliance. Laboratories and industries rely on certified weights to meet ISO 9001 or Good Manufacturing Practice (GMP) requirements, making them indispensable for quality control.
Structure and Working Principle
Weights are typically cylindrical or rectangular with a knob for handling. High-precision grades (e.g., E1) are machined to minimize surface area, reducing air buoyancy effects. Stainless steel (Grade 304 or 316) is preferred for its low magnetic susceptibility and corrosion resistance. Lower-class weights may use cast iron with a protective lacquer. The working principle relies on gravity acting on the mass to generate a measurable force. In calibration, a weight’s known mass compares against the scale’s reading to detect deviations. Adjustable weights with threaded inserts allow fine-tuning. Some advanced sets include built-in calibration certificates with traceability to national standards like NIST (USA) or PTB (Germany).
Key Features
Precision weights are characterized by their material density, surface finish, and edge design. Class E1 weights have a polished surface to prevent dust adhesion, while Class M3 may have a rougher finish. Magnetic properties are strictly controlled; high-grade weights exhibit magnetic permeability below 1.05. Durability is ensured through hardening processes or coatings like chromium. Many sets include a storage case with foam inserts to prevent damage. For user convenience, weights often feature size-coding (color or marking) per OIML R111. Anti-counterfeiting measures, such as laser engraving of serial numbers, are increasingly common in certified products.
Application Areas
Laboratories use analytical weights (1 mg–1 kg) for sensitive measurements in chemistry or pharmacology. Industrial applications include bulk material handling with large-capacity weights (up to several tons). Legal metrology authorities employ them to inspect commercial scales for fair trade compliance. In aerospace, weights calibrate force measurement systems for aircraft components. Jewelers rely on fractional weights (0.001 g) for gemstone assessment. Educational institutions incorporate them into physics experiments to teach mass and force concepts. Specialized applications include underwater calibration with hydrodynamic designs or vacuum environments with non-outgassing materials.
Maintenance and Precautions
Regular cleaning with lint-free cloths and alcohol preserves accuracy. Avoid fingerprints, which can add up to 0.1 mg of mass. Storage in temperature-controlled environments (20±2°C) minimizes thermal expansion effects. Humidity above 60% risks oxidation, especially for iron-based weights. Recalibration intervals depend on usage frequency and class—annual for E1, biennial for M3. Always lift weights by the knob to prevent edge wear. Transport in shock-absorbing cases. For legal-for-trade applications, use only weights with valid verification marks. Never stack weights unless designed for it, as scraping alters mass.
B2B Procurement Guide
Procure weights based on required tolerance (e.g., ±0.5 mg for Class F1) and traceability needs. Suppliers should provide ISO/IEC 17025-accredited calibration certificates. Bulk purchases for factories may prioritize cost-efficiency (e.g., cast iron), while labs invest in stainless steel. Verify supplier compliance with OIML R111 or ASTM E617. Key manufacturers include Sartorius, Mettler Toledo, and Rice Lake. Lead times vary: standard sets ship in 1–2 weeks; custom orders (e.g., non-standard masses) may take 4–6 weeks. Negotiate volume discounts for orders above 50 units. Consider renting calibration weights for temporary needs to reduce capital expenditure.
Related Manufacturers
- 主营：传感器、电磁阀、保护器、不锈钢砝码、地磅、电动脚手架、装载机电子秤、机械抓手、砌筑升降平台、光伏板升降机、内撑吊具、混凝土振动棒、打标机、研磨机、裁切机、平移门电机、超市防盗门、磨片磨头、滑移机、消防机器人、农业打药机、履带底盘、消防器材
- 主营：打印秤、电子地磅、小型磅秤、标准砝码、电子台秤、电子称台、重量变送器、电子天平称、计重电子秤、精密电子秤、电子天平秤、防水电子计数秤、高精度称重模块、称重传感器、测力传感器、扭矩传感器、配料秤、称重模块、波纹管传感器、无人智能称重货架、皮带检重秤、金属检测机、失重秤、喂料机、应变片称重传感器、轮式称重传感器
- 主营：电子地磅、不锈钢地磅、防水秤、不锈钢砝码、铸铁砝码、钢包砝码、单钩砝码、双钩砝码、配重砝码、增坨砝码、电梯砝码、镀铬砝码、防爆秤、液化气罐装秤、汽车衡、滚筒秤、自动检重秤、电子天平、叉车秤、钢瓶秤、电子吊秤、称重模块、电子台秤、无人值守称重系统、地磅自助过磅系统
- 主营：全自动影像仪、2.5次元影像测量仪、一键闪测仪、拼接闪测仪、轮廓度测量仪、粗糙度测量仪、圆度测量仪、大理石平台、大理石平台构件、高低温试验箱、防潮柜、Mitutoyo三丰、Mahr德国马尔、Nikon尼康
- 主营：拉力机、轮廓仪、闪测仪、砝码加荷维氏硬度计、轴承保持架、影像测量仪、拉力试验机、自动影像仪、压力试验机、测量台面表座、二次元测量仪、垂直度测量仪、轮廓扫描测量仪、光学图像测量仪
- 主营：养护箱、震摆仪、点荷仪、混凝土、测试仪、测定仪、对色灯箱、橡胶厚度、油漆涂料、凸试验机、手动升降、腻子涂刮、砂浆试模、漆膜厚度、涂料流平、涂料平板、数显砂浆、水泥胶砂、数显旋转、水泥压力、金属钢制、荧光紫外、乳化沥青、涂4粘度计、旋转粘度计
- 主营：养护箱、震摆仪、点荷仪、荷重砝码实际重量250g、混凝土、测试仪、测定仪、橡胶厚度、油漆涂料、凸试验机、腻子涂刮、砂浆试模、漆膜厚度、涂料流平、数显砂浆、水泥胶砂、数显旋转、水泥压力、金属钢制、荧光紫外、乳化沥青、涂4粘度计、旋转粘度计
- 主营：分光光度计、原子吸收、气相色谱仪、离子色谱仪、火焰光度计、水分测定仪、电位滴定仪、熔点仪、显微镜、水质、电化学、电子天平、COD、BOD、酸度计、电导率、溶解氧、光谱仪、色谱仪、离子计、紫外可见分光光度计、可见分光光度计、便携式水质、多参数水质、原子吸收光谱仪
- 主营：螺旋电子、电子皮带、皮带电子秤、链式砝码、配料计量秤、称重给煤机、称重给料机、电子皮带秤、称重显示控制器、称重仪表、非标自动送煤机、给煤机配煤系统定制、耐压式称重给煤机、皮带秤、给煤机
- 主营：消防机器人、履带运输车、漏电探测仪、不锈钢砝码、巡检机器人、消防箱、消防服、破拆工具组、干粉灭火器、打药喷雾机、传感器、电磁阀、保护器、电动脚手架、装载机电子秤、砌筑升降平台、光伏板升降机、内撑吊具、混凝土振动棒、打标机、裁剪机、研磨机、压铆机、小型装载机、洗消剂、防爆风机
- 主营：沥青仪器、土工布实验仪、粗粒土实验仪、金属标尺标配砝码套装、路强仪、固结仪、鼓风干燥箱、砂浆抗渗仪、水泥检测仪、压力试验机、抗折抗压一体机、管材检测仪、防水卷材检测仪、门窗性能检测、保温性能检测、搅拌机、标准养护室、养护箱、恒温溢流水箱、振实台、实验夹具、实验室仪器、胀破强度试验
- 主营：分析天平、精密天平、电子天平、砝码、温湿度表、铂金坩埚、纯水机、水分测定仪、红外水分仪、粘度计、静水力学天平、酸度计、托盘天平、磁力搅拌器、振荡器、液体比重天平、学生天平、机械天平、镍坩埚、银坩埚、密度天平、十万分之一天平、大量程电子天平、交直流两用天平、精密电子天平
- 主营：混凝土仪器设备、防水卷材仪器设备、涂料仪器设备、标配砝码套装杠杆天平、沥青仪器设备、岩石仪器设备、管材仪器设备、集料仪器设备、保温材料仪器设备、砖瓦仪器设备、钢筋仪器设备、人造板仪器设备、石膏仪器设备、砂浆仪器设备、密封胶仪器设备、土工仪器设备、水泥仪器设备、试验夹具、交通安全仪器设备
- 主营：码头桩、固定船、系船桩、输送机、系船柱、系缆桩、铸铁码头、铸铁羊角、栓船桩子、铸铁系船钩、铸铁拴船墩、港口栓船柱、鸭嘴型带缆桩、铸铁铸钢圆柱、防撞橡胶护舷、码头铸铁缆绳桩、码头铸铁栓船桩、圆底方底栓船桩、方底铸铁带缆桩、橡胶护舷防撞块、方底铸钢栓船柱
- 主营：万能试验机、土壤密度测试、抗压测试设备、粗粒土试验检测仪器、测试仪、试验机、试验箱、切割机、试验仪、土壤检测仪器、混凝土检测仪器、土工布检测仪器、沥青混合料检测仪器、电工套管实验仪器、水泥砂浆检测仪器、陶瓷检测设备、压力机、管材检测设备、防水卷材检测设备、无损检测设备、工程测绘设备、安全检测设备、粉体粉末试验检测仪器、石油沥青检测仪器