... ESSF Tungsten carbide button drill bit Φ51 Φ76 Φ100 Φ120 ESD Cast/hardened button drill bit Φ115 ESSD Tungsten carbide button drill bit Φ115 Φ115 ... . The types of steel tubes include 10#, 20#, 35#, 45#, 160Mn, 20GrMo, 35GrMo, 40Gr. The products have the characteristics ... of small-sized, heavy-wall thickness, high precision, inner or outer special shaped profiles. They are widely adept in ...