Sharif Digital Repository

In order to prevent a blow out, cooling the bit, displacement of drilling particle, etc., it is necessary to use a suitable fluid called drilling mud. The construction of drilling mud, especially the oil base, has a high cost and covers more than 20% of drilling costs, so maintaining and proper use of it is important, as well as drilling the reservoir layer due to the higher permeability of this layer than Other layers allow the drilling mud to influx into the formation, which in addition to the cost of fluid loss, damage to the reservoir, reduce its permeability and many problems during production. Therefore, in order to investigate the phenomenon of fluid loss, measure its size and... 

Currently, one of the most important problems in the field of drilling is the issue of drilling fluid loss in different formations. The problem of mud loss has been evident since the beginning of oil and gas well drilling operations, so that oil companies spend millions of dollars annually to solve the problem of mud loss. Problems such as pipe jamming, loss of rig production time, well blowout, loss of a large volume of drilling mud and damage to reservoir formations due to loss of drilling fluid are caused. Regarding the drilling variables, many factors cause the decrease or increase of the loss, the most important of which are the weight on the drill bit, drilling speed, the rate of... 

Since the early 90s, nanotechnology has contributed to several developments in a wide range of Science and industry such as medicine, Physics, Chemistry, Aerospace, electronics and Biology. In recent years, nanotechnology has also made development in the oil and gas industry. The drilling fluid is already one of the most important parts in drilling operation.The physical properties of a mud, rheological properties and minimize fluid invasion into the formation with perfect mudcake are important to assist in optimizing results. Nano-materials as one of the achievements of recent years are effective in achieving these purposes. To obtain the above properties, a variety of polymers as... 

During the over balanced drilling operation in high permeability or fractured formations, drilling fluid loss and in more severe occasions fluid lost occurs which causes many problems and dangers and delayed the drilling operation until it was repaired. On the one hand, because of the high value of this material, and on the other hand, due to the increase in rig/day costs resulting from lost circulation control, leads to a significant increase in drilling costs. In this research, polymer-fiber composites have been designed and manufactured using extrusion method and have been investigated as fluid lost control agent in the laboratory scale for the first time in Iran. The effective parameters... 

The aim of this project is designing Suitable drilling fluid applicable in deep drilling. This aim will be reached by adding a temperature-resistant polymers or nanomaterials in water-based drilling fluid, Rheological properties of drilling fluid checked. Stability of rheological properties of drilling fluids not constant in HT state. Chain of cause and effect will happen, While the temperature increases, the viscosity and yield point of the fluids decreases. cuttings transportation and removal efficiency will be decreased due to reduction in yield point and viscosity. Evaluation of The effect of these cases conclude that these effects will also impact on filtration loss. The reason is that... 

The mud loss and its impact on the formation play a vital role in the productivity of the formation and the near wellbore area. Despite the importance of the use of mud during the drilling process, one cannot overlook the issues that may be caused by losing mud into the formation. In addition to the formation damage caused by mud loss, the cost associated with such phenomenon and drilling operational issues and challenges has motivated the industry to look into different avenues to resolve the mud loss issue or reduce its impact. Evaluating the impact of such a phenomenon on these issues requires accurate modeling. In this study different models have been developed to evaluate the impact of... 

Nowadays, one of the most major problems in drilling industry is Lost Circulation in different formations. Lost Circulation increases non-productive time, expenditures and environmental damages. Lost Circulation can happen in natural or induced fractures, cavernous formations and high permeable rocks and it can be subcategorized in seepage, medium, severe or complete type based on the severity of the problem. For addressing this issue, different methods are suggested. One of the most considered of these methods is using Lost Circulation Materials (LCM). In this thesis, it was tried to manage the situation with Designing and engineering of lost circulation materials for different lost... 

Drilling of low pressure layers is one of the major problems in petroleum industry, in which requires a lightweight drilling fluid for drilling of these layers. Use of lightweight Colloidal Gas Aphron (CGA) leads to loss reduction of drilling fluid, decreases formation damage and finally, well stimulation costs will be reduced. Use of nanoparticles can improve the aphron drilling fluid performance. But there is little information in the literature about the role of natural surfactant in the presence of nanoparticles on the CGA based fluid properties. Especially, micro bubbles behavior in the presence of nanoparticles in pore scale is less considered. This study consists of two parts, in the... 

Given that the mean of the cost of drilling operation related to the required martials and preparation of the drilling fluids, therefore, the design and construction drilling fluid which omit has to be a proper rheology is essential in drilling operations and oil industry. A desirable property of the drilling fluid is the minimum fluid loss volume which can be achieved by formation of a low permeability filter cake on the wellbore. Drilling fluid filtrating invasion into the formation can cause formation damage and reduction in the productivity of the well. In drilling fluids, a series of natural synthetic and polymers may be used as fluid (filtration) loss control additives. However, high...