Shock pressure:
The higher the pressure, the higher the piston speed and the greater the energy generated. When the bit is in good contact with the intact hard rock, the maximum utilization of shock wave energy can be achieved. Conversely, when the bit is in poor contact with the rock, energy cannot leave the drill and transfer to the rock. Instead, it is reflected back into the drill chain as tension waves. Only when drilling into hard enough rock can the energy of each impact be harnessed. To reduce energy reflection when drilling into soft rock, the impact pressure or energy must be reduced. The greater any given impact pressure, the greater the stress on the drill pipe section. In order to make the service life of bit rod and bit tail as long as possible, it is necessary to ensure that the working pressure at any time should be matched with the drill chain.
Propulsive pressure:
The purpose of propulsive is to keep the bit in close contact with the rock while allowing the bit to turn. The propulsive force must be reasonably matched to the impact pressure. Low propulsive pressure will reduce the penetration rate and loosen the thread connection of the drill. The coupling sleeve overheats and produces gurgling noise indicating a low propulsive pressure setting; If you continue drilling after the connection part is loose, the energy loss will increase, the temperature of the connecting sleeve is too high, resulting in the joint part of the drill thread ablation and fracture; If the thrust is too large, the speed will be reduced, the penetration will be reduced and the risk of sticking will be presented. There is also a risk that the hole will skew because too much propulsive force will cause the string to bend.
Turning speed:
The purpose of turning is to move the bit to a new position for the next impact. When using a cylindrical bit, the perimeter between the two impacts is about 10mm. Therefore, the speed must be adjusted according to the impact frequency and bit diameter changes. The larger the drill diameter, the lower the rotational speed. Excessive speed will cause excessive wear of bit edge teeth.
The above is the relationship between drill drilling parameters and drilling effect, hoping to help you.
