Problems and developing direction of anti-collision technology in the dense well pattern area

An investigation of electromagnetic anti-collision real-time measurement for drilling cluster wells

“…If not handled properly, this type of collision may cause severe environmental pollution, human injury, or death . To this effect, study regarding the prevention of wellbore collisions is of massive practical significance to the drilling industry (Guan et al, 2010;Oskarsen et al, 2009;Sharma et al, 2009;McNair et al, 2005).…”

“…Enhancing the accuracy of instrument measurements and reducing wellbore trajectory error are the two primary methods of wellbore collision avoidance (Guan et al, 2010;Oskarsen et al, 2009). However, these methods are solely preventative e they do not measure the distance between drilling wellbores and offset wellbores in real time (Wang and Gao, 2008;Diao et al, 2011); thus, they largely fail to avoid wellbore collisions completely or effectively.…”

“…Vibration monitoring is a series of methods which prevents wellbore collisions, mainly divided into two categories: casing vibration monitoring, and Measurement While Drilling (MWD) vibration monitoring (Guan et al, 2010;Liu et al, 2012Liu et al, , 2013. The casing vibration monitoring method measures the vibration signal of the well casing head on the ground.…”

“…The MWD vibration monitoring method places an acoustic sensor in the completed target well. By monitoring the variation of vibration, the distance between the drill bit and the sensor is approximately determined in effort to prevent collision (Guan et al, 2010). Because of certain limits, such as minimum distance can only be determined when the sensor moves according to the drill bit, vibration caused by the drill bit or drill rod colliding with the wellbore will interfere with the vibration as monitored and transmission of vibration damps quickly and is subject to formation, the MWD vibration monitoring method only has with a small range and a considerably lower accuracy (Guan et al, 2010).…”

“…The devices currently in use to detect the distance between a drilling well and target well are the Single Wire Guidance (SWG) system (Guan et al, 2010;Oskarsen et al, 2009;Kuckes, 1996a), and the Rotating Magnet Ranging Service (RMRS) system (Oskarsen et al, 2009;Wang and Gao, 2008;Kuckes, 1996b). RMRS is an assistant system applied in Steam Assisted Gravity Drainage (SAGD) that guides the drilling of an injection well to ensure it is parallel to the production well (Oskarsen et al, 2009;Wang and Gao, 2008;Kuckes, 1996b;Liu and Wang, 2011;Gao et al, 2013;Al-Bahlani and Babadagli, 2009;Tu et al, 2010).…”