A New Method of Backup-Cutter Layout To Extend Bit Life Without Sacrificing Rate of Penetration

A corehead was designed, manufactured and tested to reduce fluid invasion of the core. This is obtained by minimizing the exposure time of the core to the drilling fluid in increasing the rate of penetration (ROP). The design incorporates a medium heavyset polycrystalline diamond compact (PDC) cutting structure developed in accordance with cutting models and balancing methods used for drill bits. The highest ROP is achieved by a particular hydraulic design: flow ports shape and positioning to clean the cutting structure enhance the drilled cuttings removal while preventing drilling fluid in the throat of the corehead. Moreover, an internal lip works with a special inner barrel shoe to effectively seal off mud flow from the throat. All the design features have been subjected to laboratory tests, including measurement of pressure drop across the corehead and flow visualization studies. Flow visualization tests include high-speed filming of the flow and paint tracing to indicate the special flow pattern. In conjunction with lab tests, a numerical simulation was performed using fluid dynamics software to optimize hydraulic parameters. The low invasion core bit has been used in numerous applications. The performance achieved was significantly better than the average achieved over a period of years using various PDC coreheads. The rate of penetration was increased by a factor of 4.8 and bit life by 2.3 (often with reusable condition).

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COMPRESSIVE CAPACITY OF HELICAL PILE FOUNDATION ON PEAT WITH VARIATION OF HELICAL PLATE DIAMETER

ASTONJADRO ◽

10.32832/astonjadro.v11i1.5708 ◽

2021 ◽

Vol 11 (1) ◽

pp. 76

Author(s):

Sapria Adi ◽

Ferry Fatnanta ◽

Syawal Satibi

Keyword(s):

Bearing Capacity ◽

Axial Compression ◽

Pile Foundation ◽

Peat Soil ◽

New Method ◽

Support Structures ◽

Rate Of Penetration ◽

Constant Rate ◽

Helical Plate

<p>The use of helical foundations to support structures on peat soil is still a new method. Research is needed to develop this foundation. There are 6 types of helical foundation tested on peat soil. To study the effect of helical plate diameter, plate diameters were varied with sizes 25 cm (M), 35 cm (L), and 45 cm (G). Plate positions (1, 2, 3 plates) are designed at 300 mm spacing. The axial compression bearing capacity test is carried out based on the constant rate of penetration procedure. At the beginning of loading, the load increases significantly. At a certain descent, the load begins to decrease slowly. The load-settlement curve shows that the larger the plate diameter, the greater the load it can withstand. The largest bearing capacity is produced by the GGG 30 foundation (3 plates dia.45 cm), which is 10.83 kN. LLL 30 helical foundation (3 plates dia.30 cm) provides a bearing capacity of 7.14 kN. These results clearly explain that the increase in plate diameter is directly proportional to the increase in the axial compression bearing capacity.</p>

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New and Advanced PDC Bit Design with Innovative Backup Layout Cutters Helps Extend Bit Life without Sacrificing Rate of Penetration During a Heterogeneous Application, Northwest Kuwait

10.2523/iptc-20030-ms ◽

2020 ◽

Author(s):

Hocine Boussahaba ◽

Jayaram Sugumar ◽

Kyle Vrnak ◽

Lyes Benyoucef ◽

Ashish Fadtare ◽

...

Keyword(s):

Rate Of Penetration ◽

Pdc Bit ◽

Bit Life

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Selective Sampling and Orientation of Non-Homogeneous Tissues

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100238 ◽

1968 ◽

Vol 26 ◽

pp. 98-99

Author(s):

C. C. Clawson ◽

L. W. Anderson ◽

R. A. Good

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Light Microscopy ◽

Random Sampling ◽

New Method ◽

Microscope Examination ◽

Small Areas ◽

Selective Sampling ◽

Large Numbers ◽

Specific Orientation

Investigations which require electron microscope examination of a few specific areas of non-homogeneous tissues make random sampling of small blocks an inefficient and unrewarding procedure. Therefore, several investigators have devised methods which allow obtaining sample blocks for electron microscopy from region of tissue previously identified by light microscopy of present here techniques which make possible: 1) sampling tissue for electron microscopy from selected areas previously identified by light microscopy of relatively large pieces of tissue; 2) dehydration and embedding large numbers of individually identified blocks while keeping each one separate; 3) a new method of maintaining specific orientation of blocks during embedding; 4) special light microscopic staining or fluorescent procedures and electron microscopy on immediately adjacent small areas of tissue.

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