Boring Diameter Research Articles

Design and Studying the Effect of Inner Bore Diameter of Unipolar Lens

This work investigated the development of magnetic and optical properties and the invention of a previously unused lens. Many new designs have been suggested for a unipolar magnetic lens based on changing the width of the inner bore and fixing the other geometrical parameters of the lens to improve the performance of unipolar magnetic lenses. The investigation of a study of each design included the calculation of its axial magnetic field the magnetization of the lens in addition to the magnetic flux density using Finite Element Method (FEM). it was found that the best magnetizing properties, the highest value of magnetic flux and the lowest value of band width of the axial magnetic field strength have been obtained when the width of the inner cavity was (55 mm). The effect of current density on the optical properties has been also studied, and it was found that the optical properties have been improved also, and the chromatic and spherical aberration values have decreased significantly. Thus, the lens (55 mm) was chosen as the best design among the proposed designs.

Investigation of the Mixture Formation in Gasoline Engines with Small Bore Diameter

Investigation of the Mixture Formation in Gasoline Engines with Small Bore Diameter

Computational Investigation of Compression Ratio and Bore Diameter Influence on Engine Performance and Knock Intensity

Computational Investigation of Compression Ratio and Bore Diameter Influence on Engine Performance and Knock Intensity

Development of Physical Pretreatment Method for Wood Fire Retardant Impregnation

To achieve a deeper and more uniform impregnation of water-soluble phosphorous-based fire retardants (WPFRs), in this work several physical pretreatment methods were developed including kerfing, boring, and the combination of both for structural square-wood posts in wooden buildings. Research was performed on three wood species, sugi (Cryptomeria japonica), larch (Larix olgensis), and Douglas fir (Pseudotsuga menziesii Franco), which are generally recognized as refractory wood species. The effects of pretreatment method on chemical uptake, chemical penetration, and mechanical properties were evaluated. The methods were compared with the incising method, a traditional method used for wood preservation. The results indicated that the pretreatments effectively increased the chemical uptake and penetration, especially in larch wood. Although the traditional incising method also increased the chemical uptake, it decreased the modulus of rupture (MOR) and compressive strength. The boring and combined method with a boring diameter less than 12 mm are recommended for WPFR wood impregnation.

Numerical and experimental method to determine the boring diameters of a two-stage TBM cutterhead to prevent rock burst

A two-stage tunnel boring machine (TBM) cutterhead with a pilot-enlargement boring method was presented to reduce the risk of rock bursts resulting from boring with a TBM with a large flat-face cutterhead. A reduced scale similarity experiment was designed on rock tunnel boring to determine the boring diameters of the two stages, and numerical simulation models were built. A micron X-ray computerized tomography system was adopted to examine the failure area of the excavated testing piece and validate the numerical models. Stress distribution and energy release rate (ERR) were used in the numerical simulations to evaluate the rock burst risk of the boring process. Experimental and numerical results show that rock burst is prone to occur in the upper, lower, and side areas of the surrounding rock around the tunnel, and risk increases with the lateral pressure coefficient and boring diameter. The optimal boring diameter ratio of stages 1 to 2 was determined between 0.55 and 0.59. Meanwhile, the ERR of the designed two-stage cutterhead is approximately 60% smaller than that of the flat-face cutterhead.

Study on the Relation between Bore Diameter of the Hollow Screw and Static Stiffness of the Dual-Drive System

The size of bore diameter of hollow screw, to some extent, will affect the dual-drive feed system's static stiffness, and then affect the machining accuracy of the workpiece. This paper takes the dual-drive feed system as the research object and builds its finite element model. Use the model to make static analysis in Workbench. After that, we can get the relation between bore diameter of hollow screw and static deformation of the dual-drive system. The results demonstrate that: with the bore diameter of hollow screw increases, the maximum static deformation volume of the dual-drive system gradually becomes larger. This article suggests that the appropriate design size of the diameter should be 4~10 mm. Because the corresponding static deformation of the dual-drive system changes little in magnitude within this range. These advised parameters can provide certain principles for the improvements of a hollow screw shape and size and its parametric design.

Distribution, settlement, and growth of first-year individuals of the shipworm Teredo navalis L. (Bivalvia: Teredinidae) in the Port of Rotterdam area, the Netherlands

During the period 2004–2008 the distribution, settlement, and growth of first-year shipworms ( Teredo navalis L., 1758) was studied by exposing fir and oak panels in the Port of Rotterdam area, which is situated in the Rhine-Meuse estuary in the Netherlands and covers the complete salinity gradient. Shipworms were found yearly in the western large polyhaline harbours. On only a few occasions were they were found in harbours that showed large seasonal and daily fluctuations in salinity. In 2006 the shipworm was found in fir panels 20 km upstream from the polyhaline harbours, demonstrating their ability to travel with the tidal currents over considerable distances and to settle once the abiotic conditions become favourable. Although the water temperatures allowed them to breed from April until November, infestations were not found before September, and from the size of the animals in the panels it was concluded that in the Port of Rotterdam area they spawned from August until the end of November. The settlement height was negatively correlated with the distance of the panels to the sea floor. In the first season after settlement they showed a substantial growth rate of 0.18 cm day −1. The longest shipworm found measured 36.8 cm after 4–5 months of growth after settlement. Infestations and growth were lower in oak than in fir wood. In 2006 the maximum consumption of wood by individuals settled in the same year in panels at the bottom accounted for 12.4%. Shell size and body length of the animal after the first season of growth showed a significant positive logarithmic relation. In both 2006 and 2007 a similar relation between the average boring tube diameter and the length of the animals was found. Lower river discharges leading to salinisation of the eastern part of the Port of Rotterdam area create conditions favourable for the shipworm, with serious consequences for the piles upon which the quays are built.

A Short History of Large Gas Engines

In the nineteenth century large volumes of low-energy gas were wasted from blast furnaces, despite improvements such as Neilson's hot blast process, and this prompted B. H. Thwaite, in 1894, to experiment with it as a source of fuel for gas engines. His experiments were successful and gas engines, despite the low energy content of blast furnace gas, produced almost the same power as with coal gas. However, the available engines were too small to make use of the huge quantities being wasted and consequently new and much larger engines were developed very quickly, particularly in Belgium and Germany. Bore diameter increased from about 10 inches to over 60 inches in about twenty years and water-cooled, double-acting, tandem horizontal engines were adopted. Britain and the United States were content, initially, to manufacture such large engines under licence. Still larger engines would have been made except that high piston temperatures and high thermal stresses caused failures and placed an upper limit on the bore diameter and the power per unit area of piston. British manufactures solved the problem by using large numbers of smaller cylinders, arranged vertically in tandem. Modern gas engines use up to twenty-four smaller cylinders, usually arranged in vee rather than tandem formation.

The Research of Conical Bore Diameter Measuring Method and Tool Based on Incomplete Iron Hinges

It is difficult to measuring conical bore edge sizes (especially big-end)because of its special structure , so the paper put forward a measuring method and a measuring tool based on imaginary crossing point which measure by transforming the point-contact between foot rulers measuring plane and conical bore end plane into imaginary crossing point and installed digital display device . It can measure the conical bore edge sizes directly in field-working and read the value with digital display device directly and used convenience .Its structure is simple and has certain practical value.

The Needle Bore Diameter for In Ovo Amino Acid Injection Has no Effect on Hatching Performance in Broiler Breeder Eggs.

The objective of this study was to determine if the bore diameter of needles used for in ovo injection of amino acids (AA) would affect subsequent chick hatchability. In Experiment 1, needles of different bore diameter were inserted into the egg. In Experiment 2, needles of different bore diameter were used to administer an AA solution that is identical to the AA pattern of the whole egg protein. In both experiments, 27, 24, 22, 20, and 18 gauge needles were tested. Needles were inserted to a depth of 13 mm in both experiments. Non-injected eggs were served as control in each experiment. Needle bore diameter did not affect (P<0.05) hatchability or body weight (BW) of hatched chicks in either experiment.

Anterior chamber stability during bimanual irrigation and aspiration: Theoretical and experimental analysis

Purpose: To determine the requirements for maintaining a stable anterior chamber during bimanual irrigation and aspiration (I/A) using side-port cannulas. Setting: Cole Eye Institute, The Cleveland Clinic Foundation, Cleveland, Ohio, USA. Methods: A theoretical fluid dynamic model of the closed I/A system was developed. Model predictions were compared with experimental flow measurements made on the Alcon Legacy 20000 system using a number of commercial and custom I/A cannulas. Results: Bore diameter, length, and orifice size determine the pressure-flow relationship of cannulas. Four of 18 tested irrigation cannulas were able to maintain anterior chamber stability when used with a 23-gauge/0.3 mm orifice aspiration cannula and maximum aspiration settings. All 4 had a 21-gauge lumen diameter. A shorter cannula length also contributed to higher flow. Conclusions: Anterior chamber stability during bimanual I/A required the irrigation system to have lower flow resistance than the aspiration system, which can be provided by using cannulas with larger lumen diameters and shorter lengths. Special cannula designs can provide these characteristics without requiring larger side-port incisions.

先進ボーリングの応力解放効果に関する模型実験

The advanced borings are used in many countries to prevent the gas outburst in the coal mines and their effects are widely proved. But the site experiments are not so easy, for they require a lot of time and funds.The author made a model experimental study to investigate the effect of the advanced borings on the stress relief. A three-dimensional model experimental apparatus of about 1: 80 geometrical scale was used. The boring diameter, the number of borings, the spacing of borings and the strength of model coal seam were selected as the parameters of the experiments. As the model rock mass, the gypsum plate was used and as the model coal seam, artificial seam composed of the mixture of water, gypsum and diatomite. The scale of the stress and the strength was 1: 40.The effect of the stress relief was measured by the degree of stress relief defined by the author. The relationship between this degree and the above mentioned experimental parameteres are reported. The strength of the coal seam and the boring diameter are the most important parameters which determine the effect of stress relief.

A computer-aided tunneling system (CATS) aids in planning and building an urban underground reservoir project

Abstract The Hirano River underground stormwater detention reservoir was planned as a first phase of an ambitious municipal plan to prevent flooding in the southeastern district of Osaka, Japan. The reservoir has been under construction since 1981. The concept involved in the design of the reservoir is stormwater detention through temporary storage of rainwater during heavy rainfalls in order to prevent flooding in the vicinity. The underground reservoir is a 1880-m-long tunnel with a storage capacity of 140,000 m 3 and a finished diameter of 10 m. The tunnel is being bored by the world's largest slurry shield (11.22-m boring diameter). This paper is primarily concerned with Phase I tunnel construction, in which the latest computer monitoring and data processing technology CATS (Computer-Aided Tunneling System) was applied to provide complete environmental protection. Some aspects of project planning are also discussed. The Phase I tunnel reservoir construction was completed on schedule, in time to prevent possible flooding of the area by intercepting 29,000 m 3 (approx. 29 million l) of stormwater in 40 min when a heavy rainfall poured down on July 21, 1986.

Raise boring 2oft diameter shafts : Rutherford, H E Min Congr J, V65, N8, Aug 1979, P21–23, 69

Raise boring 2oft diameter shafts : Rutherford, H E Min Congr J, V65, N8, Aug 1979, P21–23, 69

Superconducting Saddle Shaped Magnet

The research work on manufacturing and testing a superconducting saddle shaped magnet for MHD power generator has been in progress since 1966 at the Electrotechnical Laboratory. So far we have succeeded in making 29cm bore, 2.3 Tesla fully stabilized magnet. It has the following characteristics: Bore diameter 29cm, Outer diameter 76cm, Length 91cm, Number of winding layers 11, Max. central flux density B0=2.3T (at 460Amp) Fully stabilized to at least B0=2.5T (to 500Amp) Max. flux density in magnet windings 3.5T (at 460Amp) Superconductor AVCO SG-500 (4×0.25 in dia. Nb-33% Zr) Weight 1, 120kgThe magnet was precooled to about 48°K in about 16hours by helium gas refrigerator, which supplies the cooled helium gas of 42°K to the dewar in a closed loop. Then liquid helium was poured into the dewar to cool down the magnet to 4.2°K. The magnet has the energy of about 370kJ at the critical current of 460A. The transfer of the magnet energy to the parallel resistor outside the dewar was also successfully tested, that is, about 90% of the magnet energy could be transfered.

The effect of electrode dimensions on spectral line intensity in the carbon arc

Results for the spectrographic determination of trace elements in an alumina matrix, obtained by carbon arc excitation, are given for the variations in both trace element and internal standard line intensities and in the intensity ratios caused by relatively small variations of the cathode dimensions from the normal size of 2·8 mm outside diameter and a boring 8 mm deep and of 0·8 mm diameter. The elements considered are Co, Zr, Zn, Ti, V, Mo, Sn and Pb, with Fe as the internal standard, and also Zn with Cd, and Pb with Bi as internal standards. The dimensions altered, firstly with constant sample weights in the electrode include outside diameter, depth of placement of the sample in the boring and variation of the sample to carbon ratio in the boring; and secondly, with variable weights of sample in the boring, depth and boring diameter. It is shown that variation of the electrode dimensions can alter not only the line intensities but also the intensity ratios. The excitation of the elements would appear to be most seriously affected by any variable, such as the depth of the boring, which changes the relative rates of evaporation of the elements. Other factors, such as change in the electrical characteristics of the arc by increased sample weight, appear in general to have much less effect. Accurate determinations of trace elements will only be obtained if the electrode dimensions and especially that of the electrode boring depth are kept constant. On énumère les résultats obtenus à l'occasion de la détermination spectrographique d'éléments mineurs incorporés dans une base d'oxyde d'aluminium et excités dans l'arc au carbone. On considère les variations d'intensité des raies des éléments mineurs et de l'étalon interne ainsi que celles de l'intensité relative en fonction de petites variations des dimensions de la cathode. Les éléments étudiés sont Co, Zr, Zn, Ti, V, Mo, Sn et Pb, avec Fe comme étalon interne ainsi que Zn avec Cd et Pb avec Bi comme étalons internes. Il est montré que la variation des dimensions des électrodes peut modifier non seulement l'intensité absolue mais aussi les intensités relatives des raies. On ne peut espérer obtenir une détermination précise de traces qu'à la condition de maintenir constantes les dimensions d'électrode et la profondeur de la cavité y creusée. In den Tabellen der Arbeit sind die Ergebnisse systematischer Versuche wiedergegeben, die zeigen, welchen Einfluss Änderungen in den Dimensionen der Kathode bei der Kohlebogenmethode auf die Intensitäten und auf die Intensitätsverhältnisse der Analysenlinien haben. Das wird untersucht an Proben, die AI als Hauptbestandteil enthalten für die Elemente Co, Zr, Zn, Ti, V, Mo, Sn und Pb mit Fe als Bezugselement, ferner für Zn mit Cd und Pb mit Bi als Bezugselement. Es zeigt sich, dass die Intensitätsverhältnisse schon durch kleine Änderungen der Dimensionen der Kathode, besonders von deren Bohrung, beeinflusst werden, so dass hohe Anforderungen an die Gleichmässigkeit der Elektroden gestellt werden müssen.

Inerteen power capacitors : R. E. Marbury(Electric Journal, Vol. 33, No. 2

During the period 2004–2008 the distribution, settlement, and growth of first-year shipworms (Teredo navalis L., 1758) was studied by exposing fir and oak panels in the Port of Rotterdam area, which is situated in the Rhine-Meuse estuary in the Netherlands and covers the complete salinity gradient. Shipworms were found yearly in the western large polyhaline harbours. On only a few occasions were they were found in harbours that showed large seasonal and daily fluctuations in salinity. In 2006 the shipworm was found in fir panels 20 km upstream from the polyhaline harbours, demonstrating their ability to travel with the tidal currents over considerable distances and to settle once the abiotic conditions become favourable. Although the water temperatures allowed them to breed from April until November, infestations were not found before September, and from the size of the animals in the panels it was concluded that in the Port of Rotterdam area they spawned from August until the end of November. The settlement height was negatively correlated with the distance of the panels to the sea floor. In the first season after settlement they showed a substantial growth rate of 0.18 cm day−1. The longest shipworm found measured 36.8 cm after 4–5 months of growth after settlement. Infestations and growth were lower in oak than in fir wood. In 2006 the maximum consumption of wood by individuals settled in the same year in panels at the bottom accounted for 12.4%. Shell size and body length of the animal after the first season of growth showed a significant positive logarithmic relation. In both 2006 and 2007 a similar relation between the average boring tube diameter and the length of the animals was found. Lower river discharges leading to salinisation of the eastern part of the Port of Rotterdam area create conditions favourable for the shipworm, with serious consequences for the piles upon which the quays are built.