The narrow operating window between pore pressure and fracture pressure makes drilling difficult in some operations. A feasibility study of managed pressure drilling (MPD) is carried out on Iran Darquain oil field. The previous wells drilled in this field showed that mud returns were lost during drilling Gadvan formation. The present work addresses this problem by means of surface back pressure...

background: low back pain caused by work, ranked the second after cardiovascular diseases, are among the most common reasons of patients’ referral to the physicians in iran. this study aimed to determine the changes in back compressive force when measuring maximum acceptable weight of lift in iranian male students. methods: this experimental study was conducted in 2015 on 15 young male students...