Determination of Drill String Weigh-in Highly Inclined Holes Using Finite Element - Term Paper Example

Running head: Drilling String Drilling string Name Institution Instructor’s name Subject Drilling string Drilling string definition A drilling sting is a combination the components including the drill pipe, the bottom hole assembly plus the other components that make the system. It is a functional plant bringing different parts together to function as one. The Drill String, this system is combination of drill pipes, drilling tools, and the drill bit. The system's design is such that the interior section is void and spacious. This is to allow liquid substances to flow back and forth (drilling fluid) during the process. The pipes also create room for other tools that make up the system to operate within the hollow part. The parts of a drilling string A drilling string is made up of the drill pipe, the bottom hole assembly and a bit. However, other smaller parts of the drilling sting form the major sections above. Drilling process is a time consuming exercise, thus, all components in the system experiences a lot of stress. Additionally, such stress may be extreme depending on the site, this can at times subject the components much stress. If the stress goes beyond their limit, some components succumb leading to a serious breakdown. Therefore, the materials making the system should be of high quality, this is to prevent breakdown while at work and sustain continuous production. Lastly the parts that make up the drilling string include 1. The bottom hole assembly 2. Drill collars 3. Transition pipes 4. Drill pipes and 5. Drill system   Looking at each part in detail will enhance our understanding of this system how to assemble and manage the drilling processes. To start with, we shall analyze the bottom hole assembly BHA. The bottom hole assembly The bottom hole assembly comprise of a drill bit and drilling stabilizers. This part is quite involving because the materials making this part are tough and heavy to avoid breakage. Such materials help to enhance drilling because the drilling may take place through hard rock; this explains why the section requires extra weights. Similarly, this section has the down hole motor, and rotary steerable system and measurement tools incorporated into the system. The extra gadgets enhance the weight of the drill stabilizing the section. The transition pipes The next part is the transition pipes, the pipe section acts as the link between drill collars and drill pipes, these pipes are of definite length. Just like the bottom hole, the material making is heavy and tough material to enhance drilling, avoid breakage during the process, and increase stability while drilling. Transition pipes small section, which after assembly make a whole part. The stem subs play the main role joining them. Drill pipe In simpler term drill pipes make the whole system complete, these so because what we usually see at a drilling site are the drill pipes. They play a major role in linking all parts of the string. Therefore, the largest part of the drilling string constitutes the drill pipes. The whole system of the drill comprise of hollow pipes that are interconnect to the various components. The other materials operate inside the pipes. These pipes are spacious in diameter so that a lot of material can flow through. Drill stem sub system During the manufacturing process, all components are usually in small sections that require assembling before they can begins to function. Drilling stem subs make allow this assembly to take place. Actually, the stem subs enable different parts to connect and function in the proper way. The stem subs ensure that all parts remain intact during the process.  Connecting a drilling string   Connecting a drill string requires expertise to avoid making errors that may cause break down. The stem comprises the following parts Kelly, subs , stabilizers, reamers, shook absorbing tools, drilling jars, junk baskets, directional tools, information gathering tools, nonmagnetic tools , non metallic tools, mud motors Lyons and Prisga (2005). To start with, drill system sub help to connect one part to another, the rotary box connection and the tool joint box member link to drill pipe, then to the rotary pin connection with tool joint pin member. This is latter connected to the drill collar via the cross bar sub. This latter links to the bit using through the stem subs The functions of the drilling fluid as a component in drilling involves first in help in 1. Extracting waste materials from the well such material include cuttings. 2. It also helps in distribution of pressure 3. Minimizing damages to the well 4. Minimizing rusting on the components 5. Transmitting force from one point to another 6. It very useful in enhancing repair Materials for making string drill components The materials preferable in the case of different types this is because different components are undergo varied stressing conditions. In addition, some component may rust leading to failure therefore such parts will require coatings or rust resistance material. The materials are both metallic and non-metallic. Furthermore, the material making a drill will also depend on type of ground; if the ground is tough then tougher materials should make the drill. Some parts of the drill in particular the joint require non-metallic materials such as rubber. Metallic materials include industrial grade diamond, brass, and steel. The design   The design and features of drill string include large internal diameter. A large diameter enhances the drill’s flexibility. It also creates room for because of the hollow part that allows the flow of other implement through the string. Additionally, the string made of high strength pipes, research show that steel makes the pipes. Steel can withstand a lot of stress. Tensile strength at 140,000 psi allows the pipes to carry heavy material as well as convey enough force throughout the system in case complication within the pipes. Furthermore, the pipes lengths are of a special design for proper storage. Some pipes are about 9.6m; this enhances the speed during drilling and minimizes wear and tear to the pipe threads. Additionally, the system operates on two elevators; this enhances support thereby controlling stress on the pipe. Another issue to consider is that, the pipes should have a coating made from a rust free material to control corrosion and avoid interfering with the threads on the pipes. Similarly, the threads on the pipes are of a special design to enhance connection and finally the pipes call for constant checkup to establish any spoilt part.pdf. The types of stress in the string drill Drilling causes stress to the string drill components these stress include torque, tension, compression, heat, friction and wear. To start with, torque is because of rotation that is the turning effect of a force. In drilling, the components rotate at certain a certain speed the force in turn cause stress on the string drill parts. Tension refers to the ability of a beam to resist breakage. Drilling prefers metals such as diamond, steel, and brass. These metals can withstand stress, for example, steel, and diamond have greater tensile strengths and they can operate underground they carry a lot of weight. Additionally, at times when stuck a lot force it calls for great force to pull the pipes out. Similarly, the components in the system undergo compression forces form the weight that they have to support. Furthermore, the rotation speed and friction as the drill find its way deep into the well; the process generates a lot of heat. Therefore, drill components should withstand such conditions. The effects of drilling on human life and the environment Drilling as process can be harmful to the environment and human being as well. There is a possibility of contaminating water this can cause death if the chemicals are consumed. Additionally, harmful gases may escape into the environment and threaten humanity. Drilling may also become a health hazard because empty pits left open can cause deaths due to drowning. Furthermore, such pits hold water, this turns into breeding grounds for parasite causing diseases like malaria. Drilling may also affect the normal flow of water thus interfering with river courses. This may become problematic as it can cause landslides killing people. Similarly, the lives of drill personnel are at time put at risk, occurrence of accidents during drilling can result to loss of lives. Such incidence will have negative effects on the dependants thus interrupting the social setting of the family. Drilling affects, the environment differently for example it once water is contaminated this will cause poisoning to the fish. Death may result or mass migration of the marine life, this is common in deep sea drilling. Spilling the well products into the sea limits the amount of oxygen in the water; this will pose great danger to animals that depend on water for their livelihood. Additionally, drilling in on dry land any uncontrolled spill over will adversely affect plants. Finally, people tend to migrates into prospects areas to secure job this in turn attracts other vices such as social evils into the region. Thus, drilling may cause degradation of an area which again negative effect. In other occasions, people tend to migrate from their areas of residence to the areas that show prospects in order to secure jobs in those areas. This in turn leads to the attraction of evil therefore giving rise to the crime rate in the prospective areas. This shows that drilling in one way or another may lead to moral degradation of a given area which adds up to drilling affects on the human life. Types of wells There are different methods of classifying wells they include. These methods largely depend on the product from the well; a well may adopt a name oil or gas well if it produces them. These classifications are; 1. Either by land or offshore well. 2. Classification by looking at their purpose e.g. production well, appraisal well, exploration well, and wildcat well. 3. Wells that are already producing could have a different classification as oil producers, gas producers, and water producers. 4. Wells classification can also according to the nature of the drilling for example direction. Direction wells for example horizontal wells are inclined at an angle unlike vertical wells. These types of wells are preferable because they are easily accessible. Additionally, such wells may have more than one outlet or even a tunnel to allow free flow of materials as well as entry for personnel.  Finite element magnetic FEM While drilling a well some events are difficult to anticipate, this makes it difficult to prevent breakdowns form occurring. However, with modern technological advancement new designs have come strongly solving this myth. Such discoveries include the finite element machines. The finite element is a designs meant to calculate facilitate calculations of complex differential equations by creating similar ones and providing solutions. The analysis attempts to simulate events in the drilling system which are complex such static or dynamic in string drills. The machine seek to simplify calculations when determining the effects of rough terrain in drilling wells as well as alleviating failure caused by bending of strings and metal fatigue. Benefits of the FEM Through simulations, finite element is able to provide visible situations particularly where the items are bending. It is able to show the distribution of stress within the object, thus, providing vital information to manufacturers who in turn enhance their products. Furthermore, FEM helps in calculating the maximum load we can apply to drill string by determining on and enhancing on the weak points. The knowledge of these properties has lead to greater improvements. According to Hasting, Juds and Breuer, FEM has facilitated production. Additionally, it has led development if quality designs and improving on production rates, it has led to reduction design making, it facilitates accuracy and returns. All this advantages affect the drilling industry positively because more tools that are reliable are in the market at lower prices. Additionally drilling industries are recording fewer cases of breakdowns. In conclusion, the process of extracting minerals is quite involving in terms of work force and time. It requires a lot of monitoring so that any change that can lead to breakdown does not progress to critical levels. A string drill has many components such as the bottom hole assembly, drill pipes and many other, this sections work together and a failure in one would mean that the system is down. Different parts of the drill encounter challenges during drilling and could breaks down. However, with the finite element magnetic analysis challenges during drilling are minimal. Moreover, the FEM is the main source of technological success today because solutions to possible challenges no longer disturb humanity. It has lead to a decline in the cost of production as well as reducing chances of halting drilling. However, as man advances in technology there are challenges the development pose to him and his environment. Some of these challenges include environmental pollution, degrading certain areas and global warming. On the other hand, not all drilling effects are negative some are positive. They include economic development brought about by the returns from the drilling process. Finally, manufacturing drilling parts, assembly and operating the drilling process today is successful even though some incidences do occur. Bibliography Lyons, W.C., Plisga, G.J. (2005). Standard hand book of petroleum gas engineering. Essvier. Hasting, J.K., Juds, M.A., & Breuer, J.R. (1985). Accuracy and Economy of finite Element magnetic. Mohammed, A.M. (1992). Petroleum engineering handbook for the practicing engineers, Tulsa, okla: pennwell. ADAM T. BOURGOYNE, J. L. (2002, September). Study of Drill String Safety Valves. Retrieved November 29, 2010, from http://www.boemre.gov/tarprojects/008/008DP.pdf Program, O. D. (2008). Drill String. Retrieved November 29, 2010, from Ocean Drilling: www.oceandrilling.org Read More