Drilling Efficiency and Cost for Different Drill Technology in Loose Stratum Ying Chen Doctoral student, Faculty of Engineering, China University of Geosciences, Wuhan, 430074, China e-mail:
[email protected] Longchen Duan* Professor, Faculty of Engineering, China University of Geosciences, Wuhan, 430074, China *Corresponding Author, e-mail:
[email protected] Yubei Lu Professor of engineering, Henan Engineering Research Center of Deep Exploration, Zhengzhou, 450053, China e-mail:
[email protected] Ye Wu Professor, Henan Institute of Engineering, Zhengzhou, 451191, China e-mail:
[email protected] ABSTRACT This study aims to analyze the drilling efficiency and cost in loosen stratum. Drilling technology includes mud positive circulation, pump-suction reverse circulation, and air downhole hammer. Drilling efficiency and cost data of 75 drilling projects in loosen stratum in Henan Province, China, were analyzed. Result shows the air downhole hammer has the highest drilling efficiency among drilling technologies in this study, and the average drilling efficiency is 3.76 and 2.17 times compared with mud positive and mud reverse circulation drilling technologies, respectively. The pump-suction reverse circulation drilling technology has the lowest cost in this study. The field study shows air downhole hammer drilling technology can be used in loosen stratum, and the cost still has reducing space. KEYWORDS: Drilling efficiency, drilling cost, mud positive circulation, pump- suction reverse circulation, air downhole hammer INTRODUCTION Drilling technology is widely used in geology exploration and engineering field, such as geotechnical engineering investigation, geological exploration, hydrological well, and water well drilling. Since drilling technology was invented, nowadays different types of drilling technology are being used in the drilling field.