PDF Publication Title:
Text from PDF Page: 006
Drilling Technology and Costs structure hardness or heel row (the outer row of cutters on a rock bit) protection for geothermal drilling applications. The hard, abrasive rocks encountered in geothermal drilling causes severe wear on the heel row and the rest of the cutting structure. This sometimes results in problems with maintenance of the hole diameter and protection of the bearing seals. In some instances, mining insert bits have been used (especially in air drilling applications) because they were often manufactured with harder and tougher insert material. Problems with drilling through hard formations has been greatly improved by new bearings, improved design of the heel row, better carbides, and polycrystalline diamond coatings. Bit manufacturing companies have made good progress in improving the performance of hard formation drill bits through research on the metallurgy of tungsten carbide used in the insert bits and through innovative design of the bit geometry. Journal bearing roller cone bits are also proving to be quite effective. However, cutting structure wearrates in fractured, abrasive formations can still be a problem, and bitlife in deep geothermal drilling is still limited to less than 50 hours in many applications. When crystalline rocks (such as granite) are encountered, the rate of advance can be quite slow, and impregnated diamond bits may be required. Polycrystalline diamond compact (PDC) bits have had a major impact on oil and gas drilling since their introduction in the late 1970s, but did not have a similar effect on geothermal drilling. Although PDC bits and downhole mud motors, when combined, have made tremendous progress in drilling sedimentary formations, PDCbased small element drag bits are not used in hard fractured rock. Lost circulation. Lost circulation is a drilling problem that arises when the circulation of the drilling fluid is interrupted and it does not return to the surface. The return flow in the annulus is laden with cuttings cleaned from the well. The sudden loss of fluid return causes the cuttings to be suspended in the annulus and/or to fall back down the well, clogging the drill pipe. With a total loss of fluid return, the drilling fluid must be mixed and pumped fast enough to sustain flow and keep the bit clean, which can be an expensive process. Lost circulation exists in oil and gas drilling, mining, and in waterwell drilling as well, but is much more prevalent in geothermal well drilling. Lost circulation can be quite severe in the top 300 to 500 m (1,000 to 1,600 ft) of formations where subhydrostatic conditions exist, leading to standing fluid levels substantially below the surface. Top sections are often weathered and disturbed and may allow leakage into the formation. Lost circulation in geothermal projects tends to be near the surface, while lost circulation generally occurs at greater depths in oil and gas drilling, which can have a greater impact on overall drilling costs. Fluid flow from the hole into the loss zone may also remove cement, preventing completion of a sheath around the casing from the shoe to the surface, or from the shoe to the liner hanger. Problems with lost circulation during drilling have been reduced somewhat by the greater use of aerated drilling fluids or air drilling. Air drilling is another technology that has been adapted from the oil/gas and mining industries. Geothermal reservoirs are quite often underpressured and prone to lost circulation, which can make for very difficult casing and cementing procedures. Air or aerated drilling fluids reduce the effective density of the fluid column and therefore may permit drilling without loss of circulation. Aerated drilling fluids are most common, but there are various ways in which air is introduced to affect density reduction. One form of air drilling, utilizing dualtube 67 Chapter 6PDF Image | Drilling Technology and Costs
PDF Search Title:
Drilling Technology and CostsOriginal File Name Searched:
egs_chapter_6.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |