Drill Pipe

Drill pipes are divided into two types: friction-type and self-locking type;
Friction-type drill pipes are generally used for drilling in softer strata, and can drill through silt layers, soil, (mud) sand layers, pebble layers, strongly weathered rock layers, etc.
Self-locking drill pipes can be used not only for drilling in softer strata, but also for drilling in harder strata.
They can drill through strongly weathered rock layers, moderately weathered rock layers, slightly weathered rock layers, etc.