Izicelo Zokumbiwa/Ubunjiniyela be-Dome PDC kanye ne-Conical PDC

Njengoba kuboniswe esithombeni esingezansi kwesokudla, i-dome PDC kanye ne-carbide inserts zifakwe nge-percussion bit efanayo. Ngemva kokuhlola, i-carbide inserts iyaguga.