Reasonable selection of tool materials

Select tool materials based on the hardness, toughness, and other characteristics of the workpiece material. For example, when processing alloy steel with high hardness, hard alloy cutting tools can be used, which have high hardness and good wear resistance; For materials that are prone to adhesive wear, such as aluminum alloys, diamond coated cutting tools with good adhesion resistance can be used.

New tool materials such as ceramic tools and cubic boron nitride (CBN) tools can also effectively reduce wear under certain specific working conditions. Ceramic cutting tools have high hardness, high wear resistance, and good chemical stability, making them suitable for high-speed cutting of high hardness cast iron and quenched steel; CBN cutting tools have a hardness second only to diamond, good thermal stability, and can significantly reduce wear when cutting black metals.

Optimize cutting parameters

Cutting speed: Excessive cutting speed can cause a sharp increase in tool temperature, accelerating tool wear. Generally speaking, the appropriate cutting speed should be determined based on the matching situation between the tool material and the workpiece material. For example, when using high-speed steel cutting tools to process medium carbon steel, the cutting speed is usually between 20-30m/min; When using hard alloy cutting tools to process the same material, the cutting speed can be appropriately increased to 80-120m/min. But this is only a rough range, and adjustments need to be made through experimentation and experience in practical applications.

Feed rate: Excessive feed rate can increase cutting force, leading to increased mechanical wear of the tool. The reasonable feed rate should be determined based on factors such as the diameter of the tool and the material of the workpiece. In deep hole drilling, the feed rate of small diameter tools (such as those with a diameter less than 10mm) may be around 0.05-0.15mm/r, while the feed rate of large diameter tools (such as those with a diameter greater than 20mm) can be around 0.15-0.3mm/r.

Cutting depth: The selection of cutting depth should consider the strength of the tool and the allowance of the workpiece. Excessive cutting depth may result in excessive cutting force on the tool, causing chipping or excessive wear. In the rough machining stage of deep hole machining, the cutting depth can be appropriately increased to improve machining efficiency, but in the precision machining stage, the cutting depth should be reduced to ensure machining accuracy and reduce tool wear.

Ensure a good supply of cutting fluid

Selection of cutting fluid type: Choose the appropriate cutting fluid based on the machining material and tool material. For example, when processing steel parts, using emulsion containing extreme pressure additives can effectively reduce cutting temperature and friction; For non-ferrous metals such as aluminum alloys, using cutting oil can prevent oxidation and corrosion.

Cutting fluid pressure and flow control: Ensure that the cutting fluid has sufficient pressure and flow to smoothly enter the cutting area, playing a role in cooling and lubrication. In deep hole drilling, the pressure of cutting fluid generally needs to reach 2-5 MPa, and the flow rate should be determined according to factors such as tool diameter and machining depth. For example, for a deep hole with a tool diameter of 10mm and a machining depth of 500mm, the cutting fluid flow rate may need to reach 10-15 L/min to ensure that chips can be effectively washed away while reducing tool temperature.

Proper installation and use of cutting tools

Tool installation accuracy: When installing the tool, ensure the coaxiality between the tool and the machine spindle. If the coaxiality error is too large, it will cause eccentric cutting of the tool during the machining process, leading to increased unilateral wear of the tool. Professional tool centering devices can be used to adjust the tool position, ensuring coaxiality within the allowable tolerance range (generally less than 0.02mm).

Control of tool overhang: If the tool overhang is too long, the rigidity of the tool will decrease, and it is easy to produce vibration under the action of cutting force, thereby accelerating tool wear. In deep hole drilling, the tool overhang should be minimized as much as possible. According to the tool diameter and processing requirements, the overhang is generally controlled within 3-5 times the tool diameter. For example, if the tool diameter is 10mm, the overhang should ideally not exceed 50mm.

Regularly inspect and maintain cutting tools

Tool wear monitoring: During the machining process, timely detection of tool wear is achieved by observing changes in machining parameters (such as cutting force, cutting power, etc.) or using a tool wear monitoring system. For example, when the cutting force increases beyond a certain threshold, it may be caused by tool wear; Some advanced CNC systems can monitor the wear status of cutting tools through built-in sensors and issue timely alerts.

Tool grinding and replacement: Regularly grind the tool to restore its geometric shape and sharp edge. When the tool wear reaches a certain level (such as 0.3-0.5mm wear on the back cutting surface), it is necessary to replace the tool in a timely manner to avoid excessive wear affecting the machining quality and efficiency.