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Coiled Tubing Drilling
Coiled Tubing Drilling (CTD) is a drilling method that combines coiled tubing and directional drilling. Drilling Market Focus: Coiled Tubing Use Growing Faster than Drilling Industry, The Oil and Gas Journal, 19 Sept 2005, Retrieved 30 July 2014 It uses a mud motor to create a system for reservoirs. Niobrara Wells Prove BHA for Coiled Tubing, Drilling Contractor, 15 Mar 2012, Retrieved 30 July 2014 , Introduction to Coiled T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coiled Tubing
In the oil and gas industries, coiled tubing refers to a very long metal pipe, normally in diameter which is supplied spooled on a large reel. It is used for interventions in oil and gas wells and sometimes as production tubing in depleted gas wells. Coiled tubing is often used to carry out operations similar to wirelining. The main benefits over wireline are the ability to pump chemicals through the coil and the ability to push it into the hole rather than relying on gravity. Pumping can be fairly self-contained, almost a closed system, since the tube is continuous instead of jointed pipe. For offshore operations, the 'footprint' for a coiled tubing operation is generally larger than a wireline spread, which can limit the number of installations where coiled tubing can be performed and make the operation more costly. A coiled tubing operation is normally performed through the drilling derrick on the oil platform, which is used to support the surface equipment, although on p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Directional Drilling
Directional drilling (or slant drilling) is the practice of drilling non-vertical bores. It can be broken down into four main groups: oilfield directional drilling, utility installation directional drilling, directional boring (horizontal directional drilling - HDD), and surface in seam (SIS), which horizontally intersects a vertical bore target to extract coal bed methane. History Many prerequisites enabled this suite of technologies to become productive. Probably, the first requirement was the realization that oil wells, or water wells, do not necessarily need to be vertical. This realization was quite slow, and did not really grasp the attention of the oil industry until the late 1920s when there were several lawsuits alleging that wells drilled from a rig on one property had crossed the boundary and were penetrating a reservoir on an adjacent property. Initially, proxy evidence such as production changes in other wells was accepted, but such cases fueled the development of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unconventional Gas
Unconventional gas is natural gas obtained from sources of production that are, in a given era and location, considered to be new and different when compared with conventional gas. Sources that are at times considered to be unconventional include the following: * Coalbed methane * Methane clathrate (gas hydrate) * Shale gas * Synthetic natural gas, such as oil shale gas * Tight gas Tight gas is natural gas produced from reservoir rocks with such low permeability that massive hydraulic fracturing is necessary to produce the well at economic rates. This natural gas is trapped within rocks with very low permeability, in other ... As noted by the International Energy Agency (IEA) in 2013 regarding unconventional oil, what is conventional vs. unconventional changes over time as technologies and economies change. (see alsIEA 2013 Certainly, this applies to unconventional gas as well. Natural gas, whether conventionally produced or not, has been considered to be an unconventiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Gasification
Coal gasification is the process of producing syngas—a mixture consisting primarily of carbon monoxide (CO), hydrogen (H2), carbon dioxide (CO2), methane (CH4), and water vapour (H2O)—from coal and water, air and/or oxygen. Historically, coal was gasified to produce coal gas, also known as "town gas". Coal gas is combustible and was used for heating and municipal lighting, before the advent of large-scale extraction of natural gas from oil wells. In current practice, large-scale coal gasification installations are primarily for electricity generation (both in conventional thermal power stations and molten carbonate fuel cell power stations), or for production of chemical feedstocks. The hydrogen obtained from coal gasification can be used for various purposes such as making ammonia, powering a hydrogen economy, or upgrading fossil fuels. Alternatively, coal-derived syngas can be converted into transportation fuels such as gasoline and diesel through additional treatment, or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coal Bed Methane
Coalbed methane (CBM or coal-bed methane), coalbed gas, coal seam gas (CSG), or coal-mine methane (CMM) is a form of natural gas extracted from coal beds. In recent decades it has become an important source of energy in United States, Canada, Australia, and other countries. The term refers to methane absorbed into the solid matrix of the coal. It is called 'sweet gas' because of its lack of hydrogen sulfide. The presence of this gas is well known from its occurrence in underground coal mining, where it presents a serious safety risk. Coalbed methane is distinct from a typical sandstone or other conventional gas reservoir, as the methane is stored within the coal by a process called adsorption. The methane is in a near-liquid state, lining the inside of pores within the coal (called the matrix). The open fractures in the coal (called the cleats) can also contain free gas or can be saturated with water. Unlike much natural gas from conventional reservoirs, coalbed methane cont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bottom Hole Assembly
A bottom hole assembly (BHA) is a component of a drilling rig. It is the lowest part of the drill string, extending from the bit to the drill pipe. The assembly can consist of drill collars, subs such as stabilisers, reamers, shocks, hole-openers, and the bit sub and bit. The BHA design is based upon the requirements of having enough weight transfer to the bit (WOB) to be able to drill and achieve a sufficient Rate of Penetration (ROP), giving the Driller or Directional Driller directional control to drill as per the planned trajectory and to also include whatever Logging While Drilling (LWD) / Measurement While Drilling (MWD) tools for formation evaluation. As such BHA design can vary greatly from simple vertical wells with little or no LWD requirements to complex directional wells which must run multi-combo LWD suites. Prior to running a BHA most oilfield service providers have software to model the BHA behaviour such as the maximum WOB achievable, the directional tendencies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Underbalanced Drilling
Underbalanced drilling, or UBD, is a procedure used to drill oil and gas wells where the pressure in the wellbore is kept lower than the static pressure of the formation being drilled. As the well is being drilled, formation fluid flows into the wellbore and up to the surface. This is the opposite of the usual situation, where the wellbore is kept at a pressure above the formation to prevent formation fluid entering the well. In such a conventional "overbalanced" well, the invasion of fluid is considered a kick, and if the well is not shut-in it can lead to a blowout, a dangerous situation. In underbalanced drilling, however, there is a " rotating head" at the surface - essentially a seal that diverts produced fluids to a separator while allowing the drill string to continue rotating. If the formation pressure is relatively high, using a lower density mud will reduce the well bore pressure below the pore pressure of the formation. Sometimes an inert gas is injected into the dril ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
