食品工业的数字称重技术

和基于电磁力补偿传感器(EFC)相比,基于应变技术的数字称重传感器更结实,更耐用,更便宜。在食品工业应用中,能够带来更强大的生产力。

在食品和包装工业领域,数字化的制造过程能够带来更高的生产效率,大幅提高生产力。数字化的称重过程能够快速精确地测定灌装量 - 每年可节省高达数百万欧元(例如上海的达能牛奶)。并且 HBM 提供单一的平台,能对之前使用的模拟技术进行数字化改造。

食品和包装领域的公司需要满足各国的强制性条例,例如在德国需要满足 EU 包装条例 76/211/EEC。所有的条例都指明,包装量不能小于包装标示的数量。显然,精确地满足包装标示数量是至关重要的,尤其对于橄榄油,冰激凌和化妆品制造商来说。精确地满足包装标示数量往往能够带来利润的大幅提升。

物联网 (IIOT) 要求采用数字化称重技术

物联网是建立在数字化基础上的。数字化不仅带来设备之间无缝的连接,并且能提高生产效率和生产力。高精度的数字称重技术的核心是数字称重传感器,也是动态称重和包装的核心。

目前,自动检重秤制造商大多采用电磁力补偿传感器(EFC)。其和应变技术相比具有更高的精度,但价格昂贵,且比较脆弱。HBM 推出的最新一代数字称重传感器 FIT7A,在速度和精度上已经可以满足自动检重秤的测量要求。并且操作更方便,并且价格仅有EFC 60%。

FIT7A 称重传感器专门针对自动检重秤进行了优化,并且具有非常高的自然频响,这意味这稳定时间非常快。其采用 24-bit 模数转换和载频技术,具有非常高的分辨率和抗干扰能力,并带有 PLC 通讯接口。标准版本的 10 kg 量程的传感器分辨率高达0.1 g 。根据自动检重秤的设计和额定重量不同,每分钟可进行 100 到 400 次测量。

数字称重传感器优势:

  • 高速,高精度,可替代 EFC 传感器的大多数应用,造价低
  • 内置滤波器和 输入/输出 功能,不再需要 PLC
  • 坚固耐用,故障率低
  • 接插方式,更容易替换
  • 内置过载保护,防止传感器受到损坏
  • 不锈钢材料,更高卫生级别
  • 温度补偿功能,更低温漂

重力灌装原理的优势

相对于容积法来说,重量法具有更高的精度。容积法适合用于不同物理特性的物质(颗粒的导电性,粘稠性或气泡等)的灌装,而重量控制法提供更高的卫生条件(其不和灌装物质接触),更高的精度。

所有称重传感器的单一数字化平台

HBM 开发了 PanelX 单一数字化平台,兼容所有的数字传感器(以及数字化的模拟传感器)。用户可以在自动检重秤,灌装系统或是多头包装秤中使用。用户界面友好,并采用了统一的命令集,可以大大降低工作量,减少错误。另外,PanelX 不再需要使用 PLC,称重仪表以及数字 I/Os ,如果控制单元需要进行无缝连接,可以通过 PanelX 命令集和 PLC 进行通讯。

数字化平台的其他优势包括测量和控制信号的可视化以及多种分析功能,例如频率分析。分析功能能够用于维护和服务,甚至发现不是由传感器引起的故障。PanelX 直观的操作界面能够对称重过程进行优化,提高产品的整体性能。

Digitizing analog load cells

多种模拟传感器可以进行数字化。例如 PW27,其通过了欧洲卫生工程设计集团(EHEDG)认证。专门用于食品,制药和生物工程。紧致密封(IP68/IP69K),卫生级不锈钢,无边角设计使其可以采用高压蒸汽或是清洗剂进行清洁,提高设备的卫生等级。

HBM 为传感器数字化专门开发了 PAD 数字传感器仪表。通过将其和模拟传感器连接,即可实现传感器的数字化。其保护等级高达P68/IP69K,对于 2 mV/V 的信号,其数字化精度高达5,120,000,通过可选或是自动化滤波进行完整的测量信号调理,并且在非常强的振动干扰情况下,精度可能得到保证。PAD 称重仪表还可以通过 RS485 和 CANOpen 接口集成到多种系统中。

通过 PAD 和 PanelX 平台,模拟传感器可以获得数字化带来的所有优势,进行动态称重,分选和灌装,并可以用于恶劣的工作环境。其“即插即用”功能使其更适合物联网的要求。

Practical applications for digitized weighing technology

Two of the following examples from the food industry in France and China show how digital weighing technology operates efficiently and productively, saving considerable costs.

The Chinese machine manufacturer, Best Crown, fitted a rotary filler for coconut milk with the FIT5A digital load cell for its customer, Shanghai Dairy Milk. The considerably greater precision of the gravimetric filling process made it possible to reduce safety overfilling by a few grams per bottle. With a production volume of about 100,000 bottles per day, that means the coconut milk producer Shanghai Dairy Milk saves several million Euros a year.

The French dosing specialist MCPI and Jean Marc Dumont, an expert in machines for food applications, founded Fine-Spect together to develop especially powerful checkweighers. Equipped with the SG-based load cell FIT7A, it meets the special requirements of the food industry such as being completely covered in foam or being cleaned with a powerful stream of water. With an equipment protection level of IP66 and its watertight, hygienic plugs, the FIT7A offers optimum preconditions for these requirements.

Digital weighing technology is the key to greater productivity

Companies in the food and packaging industries can benefit disproportionately from IIOT and the digitization of weighing technology it offers as demonstrated by practical applications. Digital SG-based load cells are now comparable in precision to EFC load cells and they are cheaper, more rugged, easier to install and more durable.

A uniform, intuitively operable digital platform not only simplifies the configuring of digital load cells, it also makes it possible to digitize analog load cells (as required for sensitive hygienic areas) via transducer electronics.

That makes it possible to use digital weighing technology for almost any application in the food industry within or at the end of the filling process, and to readjust the process if necessary. Compared to EFC technology, SG-based weighing technology offers significantly greater efficiency and productivity with considerably lower costs.

“Saving time, effort and real money”

Considering how rugged, hygienic and precise digital SG-based weighing technology has now become, it is not only an alternative to EFC load cells it already holds a considerable advantage in many applications. One thing is very clear: Digital SG-based weighing technology saves companies time, effort and real money.

International Product Manager for Weighing Technology and OEM Sensors, HBM