- Settore: Oil & gas
- Number of terms: 8814
- Number of blossaries: 0
- Company Profile:
A type of nonreactive, easily differentiated material placed in a small portion of a circulating mud system at a certain time to be identified when it later returns to the surface from downhole. Mud tracers are used to determine mud cycle time (circulation time). Dyes, paints, beans, oats, chips, glitter or any material that will follow the mud and not be lost or destroyed can be used as a tracer. Care must be taken to use materials that do not dissolve, disperse or plug the bit or downhole motor. Mud tracers are distinct from mud-filtrate tracers.
Industry:Oil & gas
A type of organic acid derived from animal and vegetable fats and oils. Fatty acids are the raw materials used in the manufacture of many drilling-fluid additives, such as emulsifiers, oil-wetting agents and lubricants. Tall-oil fatty acids are distilled from conifer trees. Animal and vegetable fats and oils are triglycerides, which are hydrolyzed to give fatty acids (and glycerol). Fatty acids from animals are mostly saturated acids, having single bonds between carbon atoms. Tall oils and vegetable oils yield both saturated and unsaturated (double- and triple-bond) fatty acids.
Industry:Oil & gas
A type of mud that contains the three components that form a chemical buffer, whether by design or by coincidence. Buffering results from components that react with the added OH<sup>-</sup> ions (or added H<sup>+</sup> ions) forming slightly soluble or slightly ionized compounds. Water is one component of a buffer and various ions are the other components, such as bicarbonates, carbonates, lignite, lignosulfonate, silicate and sulfide. Clay solids are buffers because of their ability to accept or donate H<sup>+</sup> ions on their surface. The pH of a buffered mud will not increase as fast as expected after addition of caustic soda, for example.
Industry:Oil & gas
A type of lost circulation material that is long, slender and flexible and occurs in various sizes and lengths of fiber. Fiber LCM is added to mud and placed downhole to help retard mud loss into fractures or highly permeable zones. Ideally, fiber LCM should be insoluble and inert to the mud system in which it is used. Examples are cedar bark, shredded cane stalks, mineral fiber and hair. Often, granular, flake and fiber LCM are mixed together into an LCM pill and pumped into the well next to the zone of fluid loss to seal the formation that is taking mud from the system.
Industry:Oil & gas
A type of lost-circulation material that is thin and flat in shape, with a large surface area. Flake LCM can be prepared in various sizes. It should be insoluble and inert to the mud system in which it is used. Its purpose is to seal off fluid loss zones in a well and help stop lost circulation. Mica flakes and pieces of plastic (cellophane) sheeting are commonly used. Often, granular, flake and fiber LCMs will be mixed into one LCM pill and pumped into the zone where losses are occurring.
Industry:Oil & gas
A type of lost-circulation material that is chunky in shape and prepared in a range of particle sizes. Granular LCM is added to mud and placed downhole to help retard the loss of mud into fractures or highly permeable formations. Ideally, granular LCM should be insoluble and inert to the mud system in which it is used. Examples are ground and sized limestone or marble, wood, nut hulls, Formica, corncobs and cotton hulls. Often, granular, flake and fiber LCMs are mixed together into an LCM pill and pumped into the well next to the loss zone to seal the formation into which circulation is lost.
Industry:Oil & gas
A type of financing arrangement for the drilling of a wellbore that places considerable risk and potential reward on the drilling contractor. Under such an arrangement, the drilling contractor assumes full responsibility for the well to some predetermined milestone such as the successful running of logs at the end of the well, the successful cementing of casing in the well or even the completion of the well. Until this milestone is reached, the operator owes nothing to the contractor. The contractor bears all risk of trouble in the well, and in extreme cases, may have to abandon the well entirely and start over. In return for assuming such risk, the price of the well is usually a little higher than the well would cost if relatively trouble free. Therefore, if the contractor succeeds in drilling a trouble-free well, the fee added as contingency becomes profit. Some operators, however, have been required by regulatory agencies to remedy problem wells, such as blowouts, if the turnkey contractor does not.
Industry:Oil & gas
A type of gas detector tube that quantitatively measures a gas that is passed through the tube by the length of the stain it generates chemically in the tube. Drdger tubes are used in Garrett Gas Train tests for sulfides and carbonates.
Industry:Oil & gas
A type of drilling-fluid solid having a lower density than the barite or hematite that is used to weight up a drilling fluid, including drill solids plus the added bentonite clay. The mud engineer calculates the concentration of these and other types of solids on the basis of mud weight, retort analysis, chloride titrations and other information. Solids are reported as lbm/bbl or vol. %. Water is 1. 0, barite 4. 20, and hematite 5. 505 g/cm<sup>3</sup>. Low-gravity solids are normally assumed to have a density of 2. 60 g/cm<sup>3</sup>.
Industry:Oil & gas
A type of drillpipe whose walls are thicker and collars are longer than conventional drillpipe. HWDP tends to be stronger and has higher tensile strength than conventional drillpipe, so it is placed near the top of a long drillstring for additional support.
Industry:Oil & gas
