Internal wire guide for GTAW welding

A welding torch for gas tungsten arc welding apparatus has a filler metal wire guide positioned within the torch, and within the shielding gas nozzle. The wire guide is adjacent to the tungsten electrode and has a ceramic liner through which the wire is fed. This reduces the size of the torch and eliminates the outside clearance problems that exit with external wire guides. Additionally, since the wire is always within the shielding gas, oxidizing of the wire is eliminated

Electrode carrying wire for GTAW welding

A welding torch for gas tungsten arc welding apparatus has a hollow tungsten electrode including a ceramic liner and forms the filler metal wire guide. The wire is fed through the tungsten electrode thereby reducing the size of the torch to eliminate clearance problems which exist with external wire guides. Since the wire is preheated from the tungsten more wire may be fed into the weld puddle, and the wire will not oxidize because it is always within the shielding gas

Dropping Out in Southeast Kansas: Why Students Leave School Early

This qualitative study takes a deeper look into the lived experiences of students in southeast Kansas who have dropped out of high school. As a result, school and community leaders are better informed to create effective strategy, policy, and practice in dropout prevention. Framed as a phenomenology, data was collected by conducting in-depth, face-to-face interviews with 12 participants and a focus-group interview with four participants. The researcher administered a survey/questionnaire to an additional 15 participants. Utilizing the Streamlined Codes-To-Theory Model (Saldana, 2009); organizational, structural, and elaborative coding techniques were implemented to reduce the data into categories, which led to the establishment of common themes and conclusions for the study. The findings indicate the most common reasons participants share for their decision to drop out relates to negative school experiences, followed closely by life-events occurring outside of the school culture. Many participants stated that there was nothing anyone could have said or done to keep them in school; however, almost half said they might have been persuaded to stay in school if conditions were different. The overriding conclusion was that students who dropped out lacked the appropriate motivation to finish or complete the desired goal, to graduate. This was explained by applying the Expectancy-Value Theory of Achievement Motivation (Keller, 1987) to the study. This study concludes that dropout can be reduced by increasing the value a student places in having an education or being connected to the school. Further, chances of completing the diploma requirements can be greatly enhanced by increasing students\u27 confidence in their own ability to be successful

Automatic reel controls filler wire in welding machines

Automatic reel on automatic welding equipment takes up slack in the reel-fed filler wire when welding operation is terminated. The reel maintains constant, adjustable tension on the wire during the welding operation and rewinds the wire from the wire feed unit when the welding is completed

Even-odd parity effects in conductance and shot noise of metal-atomic wire-metal(superconducting) junctions

In this paper, we study the conductance and shot noise in transport through a multi-site system in a two terminal configuration. The dependence of the transport on the number of atoms in the atomic wire is investigated using a tight-binding Hamiltonian and the nonequilibrium Green's function method. In addition to reproducing the even-odd behavior in the transmission probability at the Fermi energy or the linear response conductance in the normal-atomic wire-normal metallic(NAN) junctions, we find the following: (i) The shot noise is larger in the even-numbered atomic wire than in the odd-numbered wire. (ii) The Andreev conductance displays the same even-odd parity effects in the normal-atomic wire-superconducting(NAS) junctions. In general, the conductance is higher in the odd-numbered atomic wire than in the even-numbered wire. When the number of sites ($N$) is odd and the atomic wire is mirror symmetric with respect to the center of the atomic wire, the conductance does not depend on the details of the hopping matrices in the atomic wire, but is solely determined by the coupling strength to the two leads. When $N$ is even, the conductance is sensitive to the values of the hopping matrices.Comment: 12 pages, 9 figure

Self inductance of a wire loop as a curve integral

It is shown that the self inductance of a wire loop may be written as a curve integral akin to the Neumann formula for the mutual inductance of two wire loops. The only difference is that contributions where the two integration variables get too close to each other must be excluded from the curve integral and evaluated in detail. The contributions of these excluded segments depend on the distribution of the current in the cross section of the wire. They add to a simple constant proportional to the wire length. The error of the new expression is of first order in the wire radius if there are sharp corners and of second order in the wire radius for smooth wire loops.Comment: 3 figure

The response of hot wires in high Reynolds-number turbulent pipe flow

Issues concerning the accuracy of hot-wire measurements in turbulent pipe flow are addressed for pipe Reynolds numbers up to 6 × 106 and hot-wire Reynolds numbers up to Rew ap 250. These include the optimization of spatial and temporal resolution and the associated feature of signal-to-noise ratio. Very high wire Reynolds numbers enable the use of wires with reduced length-to-diameter ratios compared to those typical of atmospheric conditions owing to increased wire Nusselt numbers. Simulation of the steady-state heat balance for the wire and the unetched portion of wire are used to assess static end-conduction effects: they are used to calculate wire Biot numbers, \sqrt{c_0}l , and fractional end-conduction losses, σ, which confirm the 'conduction-only' theory described by Corrsin. They show that, at Rew ap 250, the wire length-to-diameter ratio can be reduced to about 50, while keeping \sqrt{c_0}l\gt3 and σ < 7% in common with accepted limits at Rew ap 3. It is shown that these limits depend additionally on the choice of wire material and the length of unetched wire. The dynamic effects of end-cooling are also assessed using the conduction-only theory

Analysis of non uniform surface current distribution on thick and thin wire antenna

When wires are closely parallel, the surface current distribution becomes non uniform. Normal mode helical antenna is choosing in particular in order to study the effect of surface current distribution along its segmentation from the excitation segments towards the end of the antenna length. Antenna of different wire geometries such as wire thickness, and number of turn is designed to analyze anticipated results. The frequency operating in UHF band frequency spectrum is choose as a contribution towards widely application nowadays. The surface current distribution of thin wire antenna is not uniform as well for thick wire antennas. The difference is that thicker wire antennas results higher amount of current comparing to thin wire antennas. Higher amount of current of the surface wire antenna produce better gain and higher magnetic field strength value