First, diamond drill before drilling preparation
1. Check whether there is damage to the last diamond bit body, tooth loss, etc., to ensure that the bottom of the well is clean and no falling objects.
2. Handle the diamond bit carefully and place the diamond bit on the rubber pad or wood. Do not place the diamond bit directly on the iron plate.
3, check whether there is damage to the diamond bit cutter, whether there is foreign body in the diamond bit, whether there is o-type sealing ring in the nozzle hole, according to the need to install the nozzle.
two The diamond bit snaps on
1. Clean the male or female diamond bit buckle and apply the silk buckle oil.
2. Clamp the shackle on the diamond bit and lower the drill string to make it contact with the male or female buckle.
3. Put the diamond bit and the shackler together into the center of the rotary table, and then screw the screw according to the recommended torque value of the buckle.
3. Drill down
1. Run the diamond bit slowly, especially through the rotary table, BLOWout preventer, and casing hanger, to protect the cutter.
2. Pay attention to the obstructed well section in the last drilling trip. In the process of drilling, the bit should pass slowly when the diameter is reduced.
3. When it is about 1 piece away from the bottom of the well, it starts to rotate at the drilling rate of 50~60rpm and turn on a rated displacement pump to flush the bottom of the well.
4. Observe the weight indicator and torque to make the diamond bit contact the bottom smoothly.
Four. Drilling with diamond bit
1. It is not recommended to use diamond bits for section reaming.
2. If necessary, the rated displacement and low torque should be used.
Five. Diamond bit molding
1. Keep the rated displacement and lower the diamond bit to the bottom of the well.
2. Drill slowly at least 1m to establish bottom hole model.
3. Increase the bit pressure to the best value of normal drilling with an increase of 10kN each time. Excessive pressure is strictly prohibited to cause the early damage of diamond bit.
4. Adjust the roP by maintaining constant bit weight to obtain the best combination of drilling parameters.
Six. Diamond bit drilling normally
1. When encountering abrasive or hard sand and mudstone, reduce the drilling rate to extend the life of diamond bit.
2. Adjust roP and diamond bit to maintain optimal drilling performance when encountering formation changes or intersections.
3, each time the single root note the following points:
3.1 Restore the pump stroke number and check the riser pressure.
3.2 Turn on the pump before the diamond bit touches the bottom of the hole, and slowly lower the diamond bit to the bottom of the hole at an drilling rate of 50-60rpm.
3.3 Slowly restore pressure to original diamond bit and then increase ROP to original ROP.
Field application has proved that diamond bit has the advantages of fast speed, more footage, long life, stable operation, less underground accidents and good well quality when drilling in soft and medium hard strata. Diamond bits not only last longer, but also can be reused. Returning diamond bits for repair can greatly save drilling costs.
Post time: Dec-27-2021