Optimizing Carbide Tobacco Circular Cutting Blade Regrinding

Customer Issues:

• Blade Edge 6° Chamfer: The customer faced issues with edge chipping or tool breakage when using a 15mm thick grinding wheel due to the 6° chamfer on the blade.
• Low Grinding Efficiency: The fine-grain grinding process was slow, resulting in extended processing times and reduced efficiency.
• Tool Breakage with 0.005mm Infeed: At a 0.005mm infeed, tool breakage occurred frequently during finishing operations.
• Device Speed Limitation: The customer’s equipment had a maximum spindle speed of 4500rpm, which needed to be factored into the wheel and speed selection for optimal performance.

Current Grinding Method:

Rough Grinding: The customer used a 200×31.75mm 1A1 resin-bonded diamond wheel with a grain size of D46. The material removal was set at 0.5mm per pass, removing a total of 1mm around the circumference.

Finishing: A 250×31.75mm 1A1 resin-bonded diamond wheel with a grain size of 2000# was used. It took around 3-4 minutes to grind each side of the blade, with a total finishing time of about 10 minutes for both sides.

Recommended Solutions:

1. Wheel Thickness Optimization: To address the chamfer issue, we recommended using a thinner grinding wheel (around 6mm thick). This reduces the risk of edge chipping or tool breakage. If the budget allows, we suggested considering the use of custom-formed wheels for better grinding precision and efficiency.
2. Coarser Grain Size for Finishing: For hard alloy finishing, a grain size of 800# is sufficient. We advised using a coarser grain size to increase grinding speed while still achieving a high-quality surface finish. A finer grain size would lead to longer grinding times and lower efficiency.
3. Infeed Adjustment for Finishing: To prevent tool breakage, we recommended testing an infeed of 0.001mm for finishing operations. By gradually increasing the infeed by 0.001mm, the customer could improve grinding efficiency without compromising tool integrity.
4. Device Speed Adjustment: Given the 4500rpm spindle speed limit of the customer’s machine, we recommended setting the grinding wheel speed as follows: for the 200mm wheel, 2000rpm; for the 250mm wheel, 2500rpm. The customer should monitor the results and adjust the speed settings accordingly to find the optimal balance between speed and precision.

Conclusion:

By optimizing grinding wheel thickness, grain size, infeed, and spindle speed, our customer in Lithuania was able to enhance the efficiency of their hard alloy tobacco cutting blade regrinding process. These adjustments not only resolved existing issues such as tool breakage and chipping but also improved overall production efficiency. With these recommendations, the customer is well-equipped to meet future production demands with higher precision and faster turnaround times.

At Moresuperhard, we continually strive to provide innovative solutions to improve the grinding processes of our customers. If you are facing similar challenges, don’t hesitate to contact us for expert advice and tailored solutions.