Pilot drilling

The holding power of screws can be affected by the size of the pilot drill-hole, the depth of screw engagement, the outside diameter of the screw, and quality of the bone [Cochran, 1982 DeCoster et al., 1990], Therefore, the selection of the screw type should be based on the assessment of the quality of the bone at the time of insertion. Under identical conditions, self-tapping screws provide a slightly greater holding power than non-self-tapping screws [Tencer et al., 1993]. 

Holes drilled in most thermoplastics and some thermosets are generally 0.002- to 0.004-in. undersized because of thermal expansion effects. To alleviate this effect, drilling could be accomphshed in two stages. A small pilot drill should be used first, followed by the required size drill. The drill should be lifted frequently to prevent overheating. Thermoplastics may require external cooling to reduce frictional heat and gumming. Compressed air blown into the hole will help remove chips and provide some cooling effect. 

Switch the combination cutting tool from the pilot drilling mode to the cutting mode by applying air pressure to a fitting on the combination tool and observing the position of a 1-in. steel pin (refer to manufacturer s instructions). 

One operator reported that the combination head reduced the cutting time (time from completion of pilot drilling to the time the jet pump is stopped) from 2.5 hours using another bit design, to about 1.6 hours with the combination bit. 

Combination spiral reamer with pilot drill... 

The initial series of datings was carried out at the Radiocarbon Laboratory of the Institute of Physics, Silesian University of Technology (A. Pazdur). The samples from individual depressions were of very diverse age. The earliest dates are 2.7 ka and 3.4 ka BP (see Fig. 1 -craters B and E). The samples were taken from the pilot drilling with light hand equipment in winter and posed the starting point for further specialized research. 

The Athabasca deposits have been known since the early 1800s. The first scientific iaterest ia tar sands was taken by the Canadian government ia 1890, and ia 1897—1898, the sands were first drilled at PeHcan Rapids on the Athabasca River. Up until 1960, many small-scale commercial enterprises were attempted but not sustained. Between 1957 and 1967, three extensive pilot-plant operations were conducted ia the Athabasca region, each leading to a proposal for a commercial venture, eg, Suncor and Syncmde. 

Pilot Light. This is a small continuously operated flame at the end of the blooey line, and it will ignite any natural gas encountered while drilling. 

Burn Pit. This pit is at the end of the blooey line and provides a location for the cutting returns, foam and for natural gas or oil products from the subsurface to be ignited by the pilot light and burned off. The burn pit should be located away from the standard mud drilling reserve pit. 

Washing experiments have been conducted on a pilot-scale rayon washing line that employs the rain-pan technique of gravity-flow wetting. In this system, precision-drilled, stainless-steel pans are used to "rain" measured quantities of solutions onto a batt of cotton. The batt is conveyed by a perforated stainless-... 

The eqnipment feet shall be drilled with pilot holes that are accessible for nse in final doweling. 

Costs stated to include drilling, 270,000 reagents, labor, and pilot testing... 

According to the vendor, the effective treatment of 20 of diesel-based drilling muds during a pilot-scale field demonstration in 1993-1994 cost an estimated 35.00/yd (D13880R). 

Fig. 15.8. Substructure mapping, highlighting, and drill-down. Based on on-the-fly substructure query and mapping capability within SciTegic Pipeline Pilot, PGVL Hub allows user to perform substructure queries into a set of target molecules. In the example shown, a set of substructure queries globally collected and validated as undesirable substructure features to be avoided are mapped into target molecules (41b).

Apart from firearms ammunition other propellant-activated devices have numerous uses, for example, to drive turbines, to move pistons, to eject pilots from jet planes, to shear bolts and wires, to operate vanes in rockets, to act as sources of heat in special operations, to operate pumps in missiles, to clear blocked drill bits underground, to start aircraft engines, to jettison stores from aircraft, and generally for systems that require well-controlled sources of high force applied over relatively short periods of time. Propellants are also used in some blank cartridges. 

Liu F., Xu Z., Katayama 1., Yang J. S., Maruyama S., and Liou J. G. (2001a) Mineral inclusions in zircons of para-and orthogneiss from pre-pilot drillhole CCSD-PPl, Chinese Continental Scientific Drilling Project. Lithos 59, 199-215. 

Eodemann M. and Wbhrl Th. (1994) Technical performance of the pumping test 1991 in the KTB pilot-borehole. Sci. Drill. 

Unhead and decoke by drilling a 4 ft pilot hole and cutting—5 hr. 

The main tunnel has a diameter of about 11m, and was preceded by two smaller tunnels, a service tunnel 4 to 5 m in diameter, and a pilot tunnel 3.5 to 5m in diameter, placed first as shown in Figure 19.17a. The pilot tunnel was used to assess the geology to be traversed. All three tunnels were preceded by exploratory drill holes. 

Remove the template, and then drill pilot holes for the gas inlet and outlet with a small size drill then drill the final holes with the correct size drills. The pilot holes are not necessary, but they can help your drilling to be more accurate. Also, do not drill the final hole too big. 

A pilot pattern should be chosen so that the injected fluid is well controlled within the pattern. Otherwise, the fluid may be lost through directional flow channels. Then any interpretation or evaluation of the pilot performance would be difficult. When evaluation wells are drilled, cores should be taken in a closed-loop method so that reservoir conditions are maintained. These cores are used to evaluate alkaline consumption, measure relative permeabilities, and so on. Formation evaluation tests are conducted at evaluation wells. Finally, simulation models (sector models) are built to integrate all the data taken to evaluate the alkaline flooding performance. 

The location of this ASP pilot test is marked X2-X in Figure 13.37. The target layers were PBs, and there were 9 producers and 4 injectors drilled in five-spot patterns in the pilot area, as shown in Figure 13.42. The distance between... 

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