Reasonable Selection And Use Of Drill Bit

1. Reasonable selection of drill bits

In order to obtain the best drilling effect and technical and economic indexes, the drill bit must be selected reasonably. Improper selection can lead to early wear of the drill bit and affect the service life of the drill bit, therefore, based on a full understanding of the structure and working principle of the drill bit, the drill bit should be selected reasonably from the production reality, taking into account the drilling process, stratigraphic conditions, drilling equipment and other factors on the requirements of the use of the drill bit. As a reliable PDC bit company, we would like to give you instructions.

Underground coal mine with drilling measurement directional drilling supporting the use of the bottom of the hole motor, drilling depth is large, but also need to carry out branch hole drilling. Therefore, it should choose the tire body type PDC directional drill bit with fast drilling speed, long life and good slant making and slant stabilization performance. Due to the strong wear resistance of its bit body, the PDC performance chosen is excellent and the best applicable stratum is the complete rock layer of 1~8 (f≤10) level, and some soft and hard interlayer and a small amount of fissure development stratum can also be used normally.

The selection of drill bit diameter should be fully considered to make the combination of drilling tools meet the requirements of stable drilling of the bit. When drilling in the soft coal seam, you should use the plastron type PDC directional drill bit with lower tooth density, narrower diameter preservation width and receding anti-cutting teeth; when drilling in the hard coal seam and rock layer, you should use the plastron type PDC directional drill bit with medium tooth density and better diameter preservation effect. PDC directional drill bit. And a different PDC cutter may lead to different results.

2. Reasonable use of drill bits

How to use the drill bit well is the key to achieve the best drilling effect. We have types of drilling bits used in mining industry and etc. In actual production, there are often cases where the drill bit is scrapped in advance due to improper use, so in order to ensure the normal use of PDC drill bit, the following requirements must be strictly followed:

1) A reasonable drilling tool grade should be selected to ensure that the drill bit works smoothly and that the cutting teeth are not damaged by uneven forces.

2) The cutting teeth of PDC drill bits have poor impact resistance, so they should be lightly loaded and placed during transportation and handling, and it is strictly prohibited to smash, touch or throw the drill bits. The drill bit should be stored in a dry and ventilated environment.

3) When taking out the drill bit from the packing box, it should be well padded with soft material first. It is not allowed to bump or roll the drill bit on steel or other hard materials to prevent damage to the cutting teeth and threads.

4) The drill should be inspected on site before use, including whether the diameter of the drill meets the requirements, whether the connection thread is intact, whether there is damage to the cutting teeth, whether there are foreign objects in the bore of the drill, and whether the water eye and sink are smooth.

5) When installing and dismantling the drill bit, do not hit the drill bit with a hammer to avoid damage to the cutting teeth and the diameter-preserving parts, and apply grease to the threaded parts before installation.

6) Before opening the hole, trim the opening point into a pit to avoid damage caused by too much swinging of the drill bit when opening the hole. When opening the hole or after the second down-drilling, you should first drill 0.2~0.3m with light pressure, slow rotation and proper pump volume (absolutely no dry drilling is allowed), and after completing the bottom of the hole modeling, then increase the drilling pressure, rotation speed and pump volume gently and evenly, and then drill according to the normal drilling protocol.

7) Drill down slowly to prevent rock probes and dislodged rocks from touching the cutting teeth of the drill bit. Before the drill bit approaches the bottom of the hole, the pump should be turned on to fully flush the bottom of the hole and observe whether the water comes out normally to prevent the water eye of the drill bit from blocking.

8) Make sure the bottom of the hole is clean when drilling, if there are foreign objects such as dislodged cutting teeth, diameter-preserving carbide and steel parts in the hole, it will easily lead to early damage of the PDC directional drill bit.

9) Since the PDC composite piece is welded to the drill body with low temperature solder, the working drill bit must have sufficient circulating flushing fluid to ensure cooling and cleaning to it. It is strictly forbidden to cut off the water during the drilling process to avoid the occurrence of burning drill accidents and to prevent the repeated crushing of dropped pieces and rock chips, which will affect the service life of the drill bit.

10) During the drilling process, you should operate carefully and pay attention to the working conditions at the bottom of the hole at all times. If you find any abnormal vibration or no advancement, obvious increase or decrease in pump pressure, sudden decrease in mechanical drilling speed, increase in torque, etc., you should promptly investigate and lift the drill for inspection if necessary, and do not forcibly pressurize the drill.