What are the drilling methods?

  1. Jet drilling
    The high-pressure mud transported by the mud pump forms a high-speed impact jet (usually above m/s) through the drill bit nozzle, which directly acts on the bottom of the well, making full use of hydraulic energy (generally more than 50% of the pump water power acts on the bottom of the well), so that The cuttings are washed away from the bottom of the well in time or the formation is directly broken, which can greatly increase the drilling speed. A reasonable way to work is to use higher pump pressure, lower displacement and smaller drill nozzle diameter. Optimized parameter drilling is based on the analysis of drilling data, using electronic computers as a means, and using optimization methods to combine various controllable factors that affect the drilling speed (such as drill bit type, bit weight, rotation speed, mud performance, hydraulic factors, etc. ), establish a mathematical model and compile a calculation program based on the lowest cost principle. Optimal cooperation is carried out to achieve high-quality, fast and low-cost drilling work.
  2. Formation pore pressure prediction and balanced pressure drilling
    Use seismic, logging and drilling data (mechanical penetration rate, shale density, mud gravity, temperature, etc.) to conduct comprehensive analysis to predict formation pore pressure and determine possible abnormal pressure formations, and take timely measures to prevent sudden occurrences Complex underground situations such as blowout, lost circulation and well collapse. Based on the known formation pore pressure and formation fracture pressure, determine reasonable mud specific gravity and casing procedures. Drilling under conditions where the mud column pressure and formation pore pressure in the well are approximately balanced is called balanced pressure drilling. It can significantly increase the drilling rate and is also beneficial to the discovery of oil and gas reservoirs. Well control technology: When drilling into abnormally high-pressure formations and mud gas invasion or well kick occurs, calculation methods and appropriate technical measures are used to adjust the mud proportion and flow characteristics, and use hydraulic high-pressure blowout prevention equipment to control and eliminate well overflow. , to prevent blowouts.
  3. Core taking technology
    According to the design requirements, rock samples (cores) of the required layers are drilled from underground to obtain primary data for the exploration and development of oil and gas reservoirs. Commonly used coring tools are mainly composed of core drill bits, core barrels, core grabs, joints and other components. During coring drilling, the drill bit continuously cuts the rock at the bottom of the well in an annular shape, so that the drilled columnar core continuously enters the core barrel. In order to meet special needs, there are also closed coring, pressure maintaining coring and coring tools (rubber sleeve coring tools) for extremely loose and broken formations.