CNC machine tools have become the mainstream equipment in machining workshops. In typical small CNC machining shops, the tool inventory can exceed one thousand tools, and when including associated components, the total number surpasses ten thousand, with over a hundred different types. As the quantity and variety of tools increase rapidly, production workshops now house both standard and non-standard tools of various types and specifications, leading to frequent movement and exchange of large numbers of tools between the tool storage area and the machine tools. Currently, most domestic machining shops rely on manual methods and paper-based barcode systems for tool management. However, paper barcodes are easily damaged in oily or contaminated environments, and tool life can only be estimated based on experience. Tool shortages often result in the suspension of numerous machining operations, forcing machine operators to spend considerable time searching for the required tools. With the growing diversity of CNC machine tools and new product offerings, existing tool-management solutions can no longer meet current needs; therefore, radio-frequency identification (RFID) technology has been introduced.

　　RFID is a non-contact automatic identification technology that emerged in the 1990s. It features rapid scanning, compact size, strong resistance to contamination and durability, reusability, penetration and barrier-free reading, large data storage capacity, and high security, making it highly promising for applications in production data acquisition, monitoring, and data transmission. This paper, based on radio frequency technology, mounts RFID chips on tool shanks to enable the collection and management of tool information, thereby reducing overall production costs.

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　　1 Current Status and Demand in the Cutting Tool Management Industry

　　Experts at home and abroad engaged in tool management research have developed numerous tool-management software solutions; however, none of these solutions can fully meet all the requirements of tool management. As a result, current tool-management practices face the following challenges:

　　① It is impossible to analyze the records and data throughout the entire tool life cycle; tool information is only collected and monitored at discrete time points, and data from the uncut state cannot be obtained.

　　② Traditional tool management lacks M2M (Machine-to-Machine) information exchange, making integrated management impossible;

　　③ Current tool management schemes are designed solely to meet production needs and do not take into account the total lifecycle costs of tools.

　　To address the aforementioned challenges and achieve the goal of greater intelligence and automation in manufacturing, there is an urgent need to introduce new technological solutions for managing tool information. Balluff offers intelligent tool management tailored to tool usage in machine tools, enabling tool parameters to be transmitted to the machine tool and integrating tools into the machine’s tool magazine for retrieval by machining programs. Upon completion of a machining operation, the tool’s production time is written to its RFID tag, thereby enabling real-time data collection and continuous tracking of tool status.

2 Parameter Acquisition and Configuration for the Cutting Tool Information Management System

　　A tool information management system refers to a solution that, based on communication between machine tools within a manufacturing cell—such as CNC machines and tool setters—and RFID readers, leverages wireless radio-frequency technology and serial-port communication between CNC systems and RFID readers to achieve real-time monitoring and comprehensive management of tool information throughout the tool’s lifecycle. The typical tool lifecycle encompasses planning, procurement, identification, warehousing, lending, assembly, use, return, regrinding, and disposal.

　　The prerequisite for machine tool cutting-tool management is that the tools have been grouped and indexed using a tool-setting instrument. To enable the corresponding tool functions, the machine tool must perform tool magazine initialization and write the tool machining time into the tool-holder RFID tag. Given the relatively short read/write range of high-frequency RFID, the antenna must be brought close to the RFID tag via a pneumatic actuator when reading from or writing to the tool-holder RFID.

　　(1) Machine tool tool magazine initialization

　　To achieve intelligent transmission of CNC tool information, it is first necessary to rely on the CNC machine tool. To ensure that tools are automatically loaded into the tool magazine upon installation and that tool parameters are read from the RFID tag into the machine tool’s tool magazine, the tool magazine must be initialized. The specific procedure is as follows:

　　① When tool changes occur on the machine tool, the machine tool must rotate the tool turret one full revolution (see Figure 2) to reinitialize all tools in the machine tool’s tool magazine.

　　②The following operations must be performed for each tool: The CNC system, via command, actuates the pneumatic cylinder to raise the RFID reader; once the cylinder reaches its designated position, the CNC system reads the status of the proximity switch and then activates the RFID reader; the cylinder remains in this position for 500 ms, during which the CNC system uses serial communication to instruct the RFID reader to read the RFID chip on the tool holder; subsequently, the cylinder is retracted, and after the CNC system confirms that the cylinder’s magnetic proximity switch has detected the end-of-travel position, the tool continues to operate.

　　③ Functions to be controlled: A button shall be added to the CNC operator interface; each press of the button shall automatically rotate the tool turret by one full revolution, ensuring that the turret rotates one complete turn with every tool change and initializing the machine tool’s tool magazine. Direct mounting of tools onto the machine tool’s tool holder in the tool magazine is prohibited.

　　(2) Tool Production Time Records

　　When a tool is unloaded (or a tool set is removed), its production output (machining time) is recorded in the tool management system. The procedure for writing the machine tool’s machining time into the RFID tag on the tool holder is as follows:

　　① Before tool unloading or after tool setup on the machine tool, the machine records the tools in use and rotates the tool turret to log the machining time for each tool individually;

　　② The cylinder remains in its current state for 500 ms, during which the CNC system drives the RFID reader via serial communication and writes data to the tool holder’s RFID chip.

　　③ Retract the cylinder; after the CNC system verifies that the cylinder’s magnetic inductive switch has reached its designated position, the cutterhead continues to rotate.

　　To ensure the smooth execution of the aforementioned scheme, a button shall be added to the CNC control interface. Before tool unloading or after tool setup, pressing this button once will cause the machine tool to rotate one full revolution and record the tool’s cumulative operating time, thereby completing tool-life management. During the implementation of the scheme’s procedures, operators must adhere to established operating standards.

　　(3) Tool Data Storage in RFID Chips

　　Tool identification codes are critical for uniquely identifying each tool, and these codes are encoded in RFID tags to enable individual tool management. When developing the corresponding machining programs, the nominal diameter and nominal length of the tool can be determined based on its specifications and model, and the appropriate program can then be selected. Subsequently, diameter and length compensation can be applied as needed to account for actual conditions. Since the same tool may be mounted on different machine tools, and the same machine tool may process different workpieces, abnormal conditions can also arise during machining; therefore, it is essential to display the relevant machining information throughout the process. Through program control, real-time reports can dynamically present data such as the tool identification code, the workpiece being machined, the quantity produced, and any anomaly alerts, as well as additional information stored in the RFID tag, including the tool’s identification code, remaining tool life, and cumulative usage time.

　 　3 Hardware System Architecture and Software Development

　　The hardware consists of RFID tags, antennas, readers, and associated data interfaces. An RFID tag serves as the data carrier, comprising a chip and coupling elements; each RFID tag is assigned a unique electronic identifier. The RFID tag antenna functions as the transponder antenna for the RFID tag, enabling wireless radio-frequency communication between the tag and the reader through electromagnetic induction. A reader is the device used to read from or write to RFID tag information.

　　 Summary

　　By equipping cutting tools with RFID tags for full-lifecycle identification and bidirectional data exchange, and by installing RFID readers on machine tools and other equipment hosts to serve as the interface for information interaction between the RFID tags and the primary control systems, this approach leverages RFID tags as information carriers to enable communication among tools, between tools and hosts, and between hosts themselves, thereby facilitating tool-life prediction. The new solution enables comprehensive tool lifecycle management, reducing tool inventory by 20%, cutting tool costs by 10%, shortening setup time by 15%, improving equipment utilization by 10%, accelerating delivery schedules by 10%, and lowering overall costs by more than 15%.