Applications of PCD grinding machine

What is PCD grinder?

A PCD grinder is a machine tool used for grinding Polycrystalline Diamond (PCD) cutting tools. PCD is a synthetic diamond product used in various cutting applications due to its exceptional hardness and wear resistance. PCD tools are commonly used in the machining of non-ferrous metals, wood, plastics, and composites.

PCD grinders are designed specifically to sharpen and recondition PCD cutting edges, ensuring they maintain their sharpness and effectiveness over multiple uses. These grinders typically feature high-precision grinding wheels and specialized tool holding mechanisms to accurately sharpen the complex geometries of PCD cutting tools.

Why do you need PCD grinding machine?

1.Material properties of PCD

PCD is made of specially treated diamond and a small amount of binder sintered under high temperature and ultra-high pressure. The disordered arrangement of diamond grains gives PCD uniform, extremely high hardness and wear resistance. PCD can be used in cutting tools, grinding wheel dressing, geological drilling, measuring tool probes, drawing dies, sandblasting dies, etc. However, the high hardness and high wear resistance of PCD also bring great difficulties to its processing.

2.Grinding characteristics of PCD materials

(1) The grinding force is very large Diamond is the substance with the highest hardness among known minerals. The amount of wear caused by friction with various metal and non-metal materials is only 1/50 to 1/800 of cemented carbide; the hardness (HV) of PCD is 80 to 120KN/mm2 , second only to single crystal diamond, much higher than cemented carbide. When using a diamond grinding wheel to grind PCD, the initial cutting intensity is very high, about 10 times more than that of cemented carbide (0.4MPa); the specific grinding energy can reach 1.2×104 ~ 1.4×105J/mm3; therefore, the grinding force is much higher For grinding cemented carbide.

(2) The grinding ratio is very small Due to the high hardness and wear resistance of PCD (the relative wear resistance is 16 to 199 times that of cemented carbide), the grinding ratio when grinding PCD is only 0.005 to 0.033, which is about 1/1000 to 1/1000 of cemented carbide. 1/100000; grinding efficiency is only 0.4~4.8mm3/min. Therefore, in order to ensure the edge quality and removal amount of cutting tools, the grinding time is very long and the processing efficiency is very low. In addition, when the hardness, content, and particle size of PCD are different, the grinding time will also vary greatly.

(3) Granularity has a great influence PCD materials used in cutting tools are mainly divided into three categories according to their particle size: coarse-grained (20-50μm), medium-grained (about 10μm) and fine-grained (-5μm). The grinding force and grinding ratio differ by several to several times. ten times. Coarse-grained PCD has the highest grinding ratio and is the most difficult to grind. After grinding, the cutting edge is the most jagged and has the worst quality, but it has the strongest wear resistance. Fine-grained PCD has the lowest grinding ratio and is easier to grind. The edge quality is the best after grinding.

3.PCD cutting tool sharpening requirements for PCD grinders

(1) Grinder has good process system rigidity Due to the high hardness of PCD material, grinding machines must have high resistance to deformation, especially the spindle system and tool clamping system. The grinding force when sharpening PCD cutting tools generally reaches 100~500N. Therefore, the machine tool is required to have a large shaft diameter and high axial rigidity and strength of the bearing.

(2) PCD grinder has a short-range swing mechanism with adjustable stroke and adjustable speed. The grinding ratio of PCD is extremely low. The grinding mechanism of PCD is mainly the result of mechanical effects such as micro-crushing, wear, shedding, and cleavage caused by the continuous impact of the diamond grinding wheel on the PCD material, and the thermochemical effects of oxidation and graphitization. . Therefore, the use of short-range swing mechanism is beneficial to improve grinding efficiency and improve the quality of the tool edge. Generally, the swing distance is 0~50mm, and the swing speed is 20~60 times/min.

(3) The tool holder of the grinder has a high-precision rotation function and an online detection device Since PCD material is hard, brittle and wear-resistant, its tool tip is usually designed in an arc shape to help reduce the amplitude of relative vibration between the tool and the workpiece. In order to process the tool tip arc, the tool holder of the grinder should have a high-precision rotation function and an online detection device for the tool tip arc radius size and quality. This can avoid positioning errors caused by multiple clampings and double the processing efficiency.

M50 CNC PCD grinding machine

 M50 CNC PCD grinder is equipped with three CNC axes and has three-axis three-linkage CNC functions. It is suitable for processing PCD and PCBN tools such as machine clamp blades and non-standard turning tools. It can be used for both the manufacturing of finished tools and regrinding of tools. 

Feature of M50 cnc PCD grinding machine

1.The main basic parts are made of optimized wear-resistant gray cast iron material, with compact structure and stable performance. After the tool is clamped, the straight edge and arc edge processing are automatically completed without manual intervention. The grinding efficiency is high and the edge quality is good.

2.Adopting a transmission structure that combines AC servo motors, precision ball screws, high-strength rolling guide rails, and harmonic reducers, it can realize CNC movement/oscillation of the spindle, CNC rotation of the vertical axis, and CNC feed of the tool holder. and other automatic processing functions. ·

3.Equipped with high-definition imaging system, tool cleaning air blowing nozzle, fully sealed industrial visual backlight, automatic lens protection cover, pneumatic rotating support for dressing grinding wheel and other devices. .

4.Adopt the "PCD/PCBN tool automatic processing control system based on image recognition" with independent intellectual property rights.

Applications of PCD grinding machine

1.PCD tool production: PCD tool grinders are used to manufacture various types of PCD tools, including drill bits, milling cutters, turning tools, cutting knives, etc. These tools are commonly used for machining non-metallic materials such as aluminum alloys, composites, plastics and wood.

2. PCD tools regrinding and repair: With use, the cutting edges of PCD knives gradually wear out and require regular grinding and repair to restore their cutting performance. The PCD tool grinder can precisely grind and repair the cutting edge of PCD tools to regain a sharp cutting edge.

3.Custom tool production: PCD tool grinders can customize PCD tools according to specific machining requirements, including specific cutting geometries, dimensions and cutting parameters. This type of custom tool is often used for high-precision machining and special material processing.

4.High-precision machining applications: Because PCD cutting tools have excellent hardness and wear resistance, they are often used in high-precision machining applications, such as aerospace, automobile manufacturing, mold manufacturing, and other fields. PCD tool grinders ensure that these tools maintain high precision and stable performance.