DPM time management analysis for drilling a 200 m deep hole in ground investigation

Abstract

This paper applies the drilling process monitoring (DPM) method to record and analyse the digital real-time data for the full process of the hydraulic rotary coring project along a 200 m deep drillhole. According to the DPM data, the whole drill project is divided into four periods. The working period (or the full drilling process) consists of a total of 88 roundtrips and costs a total of 76.71 hours. Each roundtrip can be classified into four sections: inserting, drilling, retrieving, and extracting processes. The time distribution of each individual process along the 200 m deep drillhole is obtained by DPM data. As the drillhole depth increases, the time of the total roundtrip, the inserting process, and the retrieving process for one roundtrip increases linearly. The ground strata, the drill machine condition, and the operators’ effectiveness determine the variations in the elapsed time of the drilling process. Furthermore, four types of malfunctions and associated time distribution can be identified by the abnormal DPM data. The factual data and results presented in the paper can quantitatively describe the time distribution of individual drilling processes and provide a digital field management method for drilling information.