Application of RFID technology in the whole life cycle management of milling tools—taking end mills, face mills, and ball end mills as examples

Giving Milling Cutting Tools "Digital Sensing": The Application of RFID Technology Throughout the Lifecycle of End Mills, Face Mills, and Ball End Mills

On the stage of precision manufacturing, end mills, face mills, and ball end mills are the core "dancers" shaping modern industrial parts. They respectively undertake the crucial tasks of contour milling, planar machining, and complex surface forming, making them indispensable tools in mold, aerospace, and automotive parts manufacturing. However, the management of these high-precision, high-value tools has long been hampered by pain points such as error-prone manual registration, reliance on experience for lifespan control, and time-consuming inventory checks. The introduction of RFID technology is infusing these milling tools with a digital soul, achieving a leap from "consumables" to "data Assets."

### I. Giving Unique "Digital Identity" to Adapt to Complex Tool Structures

The first step in implementing RFID management is to establish an unforgeable digital proFile for each milling cutter. For the different structures of end mills, face mills, and ball end mills, engineers have designed flexible tag attachment solutions:

- **Embedded Tag Holder:** For end mills and face mills with standard shanks, industrial-grade anti-metal RFID tags are often embedded in non-machined areas of the shank (such as pre-drilled grooves) or fixed to the end of the shank with screws. This design ensures that the tag will not fall off during high-speed rotation and does not affect the dynamic balance of the cutting edge.

- **Clamp-mounted:** For smaller diameter ball end mills or precision tools that cannot be slotted, a dedicated anti-drop clamp is used to attach the micro-tag to the tool shank. A visible code is simultaneously laser-engraved on the tag surface for easy manual verification.

- **Intelligent Tool Holder Integration:** Some high-end solutions integrate secondary units (including RFID chips) into the tool holder, or even install the sensing unit directly near the cutting edge to monitor cutting force and temperature in real time.

During the coding process, the tool's unique code and **static information** (model, specifications, material, number of cutting edges, supplier, preset lifespan) are encrypted and written into the tag. From then on, every end mill, every face milling cutter, and every ball end mill possessed a lifelong "digital ID Card."

### II. Intelligent Management Throughout the Entire Process

Leveraging the **non-contact identification** and **batch reading** characteristics of RFID, the management of milling tools permeates the following core aspects:

#### 1. Warehousing and Issuance: From "Manual Searching" to "Second-Level Response"

RFID Readers are deployed in intelligent tool cabinets or automated shelving systems. When an operator needs a **ball end mill with a **specific radius**, the system quickly locates it using an electronic location map. Upon issuance, the operator swipes their work badge on the RFID Terminal for authentication, retrieves the tool, and the reader automatically records the issuing personnel, time, and corresponding processing order. The tool status is updated in real-time to "in use." Upon return, the system automatically checks the tool's wear and remaining life, completing an electronic ledger, improving efficiency by over 70%.

#### 2. Tool Setting and Assembly: Eliminating Parameter Errors

At the tool setting station, equipment with RFID reading and writing capabilities automatically reads the tool tag and retrieves the preset tool compensation parameters. After the operator completes the tool setting, the new **actual dimension data** can be directly written to the tag or transmitted to the machine tool's CNC system via a wireless network. For example, the integration solution of the Siemens 828D system and Balluff RFID equipment can achieve automatic conversion of tool data between the external tool setting device and the machine tool's tool table, completely eliminating manual input errors.

#### 3. Machining Process: Real-time Monitoring and Lifespan Warning

This is the most valuable aspect of RFID application. Small embedded readers are installed near the spindle or at the tool magazine entrance of the machining center.

- **Error Prevention Verification**: When the operator loads a **face milling cutter** into the spindle, the system automatically reads the tool specifications from the tag and compares them with the tool required by the machining program. If the model does not match (e.g., a roughing cutter is installed instead of a finishing cutter), the system immediately alarms or prevents startup.

- **Precise Lifespan Management:** The system accumulates the actual cutting time or number of machining operations in real time. For expensive solid carbide end mills or indexable face milling inserts, when the remaining lifespan reaches a warning threshold (e.g., 10% remaining), the system sends a replacement reminder. If the tool is used beyond its lifespan, it can even trigger machine tool shutdown to prevent workpiece scrap due to excessive tool wear. A company in Ningbo saved over 3 million yuan in tool costs annually after implementing a full-process tool management system.

#### 4. Regrinding and Scrap: Data-Driven Decision Making

Milling tools often require multiple regrindings. When a ball end mill is sent for repair due to ball end wear, the regrinding center retrieves its regrinding history via RFID to avoid over-regrinding affecting tool performance. After regrinding, new parameters (such as remaining diameter and new cutting edge status) are updated to the tag. When the tool reaches its total lifespan threshold, the system automatically marks it as "scrap" and generates a scrap list, providing accurate data for procurement planning.

### III. Intelligent Milling for the Future

RFID technology is driving milling cutters from "passive use" to "active sensing." Taking the intelligent milling cutter system developed by Huazhong University of Science and Technology as an example, by integrating sensing units near the cutting edge and utilizing RFID channels to simultaneously transmit energy and data wirelessly, the system can sense physical quantities such as temperature and vibration in real time during the cutting process. This means that future end mills will not only tell managers "who I am" and "how long I've been used," but also report in real time "how hot I am now" and "whether my vibration is abnormal."

### Conclusion

From contour milling with end mills to large-plane machining with face mills, and curved surface forming with ball end mills, RFID technology is building a digital closed loop covering the entire lifecycle of these precision milling tools, encompassing procurement, warehousing, assembly, machining, regrinding, and disposal. It is not only the key to solving pain points such as "unclear tool inventory, uncontrollable lifespan, and incorrect tool replacement," but also a crucial infrastructure for enterprises to move towards lean manufacturing and achieve data-driven operations. When every milling cutter has a "speaking" digital identity, the future of intelligent manufacturing will become clearer.