The design of coal drill bits has evolved over time, mirroring advancements in technology and materials science. Modern bits incorporate sophisticated geometries, innovative cutting structures, and advanced coatings to enhance drilling efficiency, reduce wear, and prolong service life Modern bits incorporate sophisticated geometries, innovative cutting structures, and advanced coatings to enhance drilling efficiency, reduce wear, and prolong service life Modern bits incorporate sophisticated geometries, innovative cutting structures, and advanced coatings to enhance drilling efficiency, reduce wear, and prolong service life Modern bits incorporate sophisticated geometries, innovative cutting structures, and advanced coatings to enhance drilling efficiency, reduce wear, and prolong service lifecoal drill bits. The use of polycrystalline diamond compact (PDC) and hard-faced bits has significantly increased productivity and reduced drilling costs in recent years.