Opencast Mining - Study Mode

[#141] The purpose of placing the oil bottle between drill and the receiver, when drill is working.
Correct Answer

(B) Librication

[#142] The rotational speed of drill rods by down the hole hammer drills.
Correct Answer

(D) 15 - 25 rpm

[#143] Well hole drill mast length ranges from . . . . . . . .
Correct Answer

(B) 3 - 6 m

[#144] Pore water pressure affects
Correct Answer

(B) Pit slope

[#145] The width of bench floor in mechanised quarries is usually . . . . . . . .
Correct Answer

(B) 15 m