Definition - What does Radial Drilling mean?
Radial Drilling is an innovative, economic and a very environment-friendly technique of drilling multiple micro diameter lateral horizontal wells at various levels of depths from an existing well. This type of drilling is considered to be unconventional drilling method in which the micro diameter holes are drilled by utilizing coil tubing conveyed drilling method and pumping high velocity jet fluids.
Petropedia explains Radial Drilling
In radial drilling technique, high velocity hydraulic jet fluids are injected to drill the lateral holes inside the reservoir. Here multiple lateral holes are drilled in different directions at different levels or depths from an existing well also called mother well. The depth and the direction of the micro diameter holes to be drilled are based on the economically viable volume of hydrocarbons present in the reservoir which can breakeven the cost of radial drilling.
Radial drilling can be opted by any E&P organization when the existing well is showing depleting production levels or getting exhausted. It bypasses the damaged or depleted skin zone & extracts crude oil from the regions which are untouched. RD operations are favorable for Brown fields as these fields are considered to be getting exhausted or reached their maximum production levels. RD operations need to be performed before any tertiary recovery process such as Enhanced Oil Recovery processes. The diameters of the holes are in the range of 30 to 50 mm, and the bit size is about 1.75 inches. The maximum working depth is 10000 ft., having 248 degree F temperature. Radial drilling consists of three parts: Milling; Jetting and Washing.