Using of surface back pressure with water based mud in managed pressure drilling technique to solve lost circulation problem in Southern Iraqi Oil Fields

Many drilling problems are encountered continuously while drilling oil wells in the southern Iraqi oil fields. Many of these problems are ineffectively handled resulting in a longer non-productive time. This study aims to identify the formations such as Dammam, and Hartha formations،diagnose potential problems and provide the solution for lost circulation problem. After conducting a comprehensive study on the subject and based on available data, previous studies and some information, the managed pressure drilling (MPD) method was the best technique to solve this problem. This process may use various techniques including control of back pressures .Thus, reducing the risk and control the costs of drilled wells, which have narrow pressure window by managing the wellbore pressure profile. The well plan software program provided by Halliburton Company was used, this software is based on a database and data structure common to many of Landmark’s drilling applications. Mud used with various injection rates to choose the rate that provides the conditions to achieve the best drilling process, as it using mud weights of (8.8 -8.7 ) ppg and applied a surface back pressure (50 psi). Depending on specifications of second hole the optimal injection rate was chosen using the (hydraulics) program. As a results, rate of water injection (850) gpm, is the best which it provides a good efficient cutting transport ratio (CTR), which means high stability and preventing formation damage in addition to controlling in mud losses

Investigation on moist silica sand’s circulation for sand mold printing with line-forming

Purpose This paper aims to investigate the circulation of moist silica sand to provide appropriate feeding modes and references for designing the coating device when printing sand mold with line-forming. Design/methodology/approach First, this paper briefly introduces sand mold printing with line-forming and the circulation problem brought by moist silica sand. The outlet may be choked due to poor flowability and solidification characteristic, resulting in poor dimensional tolerance and even production failure. Then, based on circulation modeling, a series of feeding modes is proposed to guarantee adequate feeding, avoid solidification and ensure successful fabrication. Finally, the GUI of control software is developed, including slicing, path planning and the function of virtual printing. Findings Several feeding modes of moist silica sand are put forward to avoid the choke. Research limitations/implications The authors will further investigate the flowability of furan no-bake sand based on experiments. Originality/value This paper is going to provide references for the novel design of nozzle, prototype and sand mold printing, influencing significantly on mold manufacturing and the casting industry. This research applies equally to equipment having the circulation of high moist particles with solidification features.

ANALISIS LOST CIRCULATION PEMOMPAAN GRAVEL SLURRY PADA SUMUR X BERDASARKAN WAKTU TUNGGU

Unconsolidated formations tend to have sand problem that can lead to decline of production in Oil and Gas Well. There are some methods can be used to resolve sand problem like liner completion, meshrite liner, perforated liner completion, and gravel pack completion. Rock type of Well X is unconsolidated stone and the method which used in that well to surmount sand problem that occurred is gravel pack method. However, during pumping of gravel slurry there are some problems, partial or complete loss of the gravel slurry into the formation (lost circulation), waiting on sand sattle is one method that has developed to resolve loss circulation. This method is done by stopping pumping slurry after the amount of incoming sand has reached teoritical and more than 50%. The aim of this research to determine volume of gravel slurry that is needed and total of lost gravel sand. Gravel slurry needed to overcome sand problem in Well X consists of 109 sacks of gravel sand, 259.5 bbl of water, and 1834 lb (18 sacks) of KCL. Analysis of pressure test line chart to find out lost circulation problem. There are 147 sacks gravel sand missing as a result of lost circulation problem from 256 sacks of gravel sand that is pumped.