• One preparation before drilling
1, Check whether there is a drill bit on the drill body damage, Diaodai, etc., to determine the bottom clean, no falling objects.
2, Take care of the drill bit and place the drill on the rubber pad or board. The drill bit is not placed directly on the iron plate.
3, Check whether the drill tooth is damaged, whether there is a foreign object in the drill bit, whether the nozzle has O type sealing ring, and install the nozzle according to the need.
• Two buckle
1, Clean the drill male buckle or a female buckle and apply the thread compound.
2, The shackle card on the drill bit, drill string assured and make the male buckle or a female buckle buckle contact.
3, The drill and shackle together into the rotary bushing, and then follow the recommended torque value of screw thread.
• Three down
1, Lower the bit slowly, through the turntable, BOP, casing hanger, especially slow, in order to protect the cutting teeth.
2, Note that the last play difficult wells drilled when the neck and leg should be met in the process of drilling bit slowly through.
3, When it is about 1 single holes at the bottom of the well, it begins to rotate at a speed of 50 ~ 60rpm, and opens a pump with a rated displacement to flush the bottom hole.
4, Observe the fingers and torque to make the drill contact the bottom well.
• Four backreaming
1, Diamond bit is not recommended for well section reaming.
2, If the need for reaming, with rated displacement, W:10 ~ 20kN, N:50 ~ 60rpm, slow low torque reaming.
• Five modelling
1, Maintain the rated displacement and lower the bit to the bottom hole.
2, Using W:10 ~ 20kN, N:50 ~ 60rpm slow drilling at least 1m, in order to establish the bottom hole model.
3, The drilling pressure is increased to the optimum value of normal drilling by increasing the amount of 10kN every time, and the pressure is too heavy to cause the initial damage of diamond bit.
4, Keep drilling pressure constant and adjust drilling speed so as to get the best combination of drilling parameters.
• Six normal drilling
1, In case of abrasive or hard sand mudstone, the drilling speed is reduced so as to prolong the bit life.
2, Drilling speed and drilling pressure are adjusted to maintain the best drilling efficiency when formation change or interlayer is encountered.
3, Pay attention to the following points every time: 3.1 restore the number of pumps and check the standpipe pressure. 3.2 start the pump before the bit contacts the bottom of the well and slowly drill the bit to the bottom hole with a drilling speed of 50 to 60rpm. 3.3 slowly restore pressure to the original drilling pressure, and then increase the drilling speed to the original drilling speed.