Common specifications: φ65, φ75, φ 94, φ 113, φ 120, φ 133, φ 153, φ173, etc. Other specifications and special requirements can be customized according to specific requirements.

The concave drill bit is a drill bit for small ordinary drilling rigs. It has a concave design. The number and size of the water holes are configured according to the number of cutter blades, providing a large slag discharge space and good stability. The model can be customized according to customer requirements, and the hardness can be customized according to the Protodyakonov hardness coefficient of the coal and rock formation.