Anode Length Research Articles

パルスアーク溶接に関する研究 ＩＩＩ パルスＭＩＧ溶接におけるワイヤの溶融速度

Melting characteristics of mild steel, stainless steel and copper alloy wires, are investigated for pulsed or constant current MIG arc using transistor controlled power supply.Results obtained are summarized as follows;(1) Wire melting rate in MIG welding is affected by many factors; effective anode melting potential, length and resistance of the electrode wire extension, heat contents of metal droplets and electric current applied.(2) Wire melting rate in pulsed MIG welding is found to be independent of pulse frequency, and is expressed as a function of average value and effective value of pulsive current applied. Even if the average current is kept constant, melting rate of electrode wire is possible to increase as the effective value of pulsed current becomes higher.(3) Heat conteut of metal droplets depends on an anode heating of MIG arc and joule's heating in a segment of the electrode wire travelling from the contact tip to the arc.

Position Sensitive Proportional Counter for Measurement of Tritium Labelled Gas Movement

A position sensitive proportional counter of a charge division type with a single resistive anode wire was constructed for the measurement of the movement of 3H labelled gas which is flowing or diffusing in a pipe. The introduction of resistors between the anode wire and pre-amplifiers brought a uniform detection efficiency for 3H β-rays throughout the counter. The position resolution was 3.1mm FWHM. Detection efficiency was almost 100% uniformly over about 700 mm in the total anode length of 740 mm. The movement of 3H labelled gas. could be measured effectively.

Position sensitive proportional counter for measurement of tritium labelled gas movement.

A position sensitive proportional counter of a charge division type with a single resistive anode wire was constructed for the measurement of the movement of 3H labelled gas which is flowing or diffusing in a pipe. The introduction of resistors between the anode wire and pre-amplifiers brought a uniform detection efficiency for 3H β-rays throughout the counter. The position resolution was 3.1mm FWHM. Detection efficiency was almost 100% uniformly over about 700 mm in the total anode length of 740 mm. The movement of 3H labelled gas. could be measured effectively.

Über die Strukturänderung der Söderberg-Anode im Laufe der Elektrolyse

Transformation of the anode structure during the electrolysis process was studied by means of thermal analysis and microscopy. The DTA method was found to be a good complement to traditional microscopic analysis. The autors succeeded in differentiating the formation and development of a secondary coke structure. The secondary coke is formed over half the anode length in the direction of the melt.

A Modified Version of the Grimm's Glow Discharge Lamp for Use as a Demountable Hollow Cathode Emission Source. III. Blackening as a Function of Discharge Parameters

Abstract The influence of anode distance from hollow cathode on the blackening∗ of spectral lines excited by means of the modified Grimm's lamp was investigated for three representative cathodic materials, i.e. aluminium, copper and graphite using argon as the carrier gas. On the basis of the experimental results as well as voltage-current characteristic curves at distances of 7, 15, 20, 25 and 33 mm, it was possible to conclude that the optimal sets of discharge parameters for all the materials investigated are based on an electrode distance of 20-25 mm. In the case of copper a distance of 33 mm was also found to be highly suitable. An increase in the emission of copper lines at the largest anodic length with increasing pressure of the noble gas was also observed, in contrast with the behavior of the same element at shorter distances. A tentative interpretation of the phenomenon is given.

The lateral spread of short glow discharges

A weakly abnormal glow discharge, started at one end of a pair of long coaxial electrodes, spreads laterally over the whole length of anode and cathode. In helium and neon at 10 Torr and for short interelectrode distances, the lateral velocity is independent of position and gas pressure when the applied voltage is kept constant. When the voltage approaches the normal cathode fall, the speed tends to zero and it rises with voltage in excess of the normal cathode fall. The spreading mechanism is assumed due to positive ions emerging from the boundary between cathode fall or negative glow and the virgin gas. Discharge expansion rate calculations are based on a model representing the boundary by an edge normal to the cathode.

Arc Duration in the Anodic Case

The anode arc is a source of erosion in electrical contacts. The erosion is thought to be proportional to the arc duration. This paper investigates the anodic arc length. A new experimental technique is described to measure arc duration. This method provided better statistics and better time resolution. By applying this technique to different metals, the experimental fact that these arcs are a succession of bursts of fixed duration became evident, The distribution of the number of arcs versus their length can be discussed in terms of the average number of bursts per unit time. Only two parameters for a given metal are sufficient to calculate the average arc length in any given circumstance. A classification o': different metals versus their tendency to sustain long anode arcs is presented.

Anode surface area and ageing of self-quenching (argon-methylal) GM counters

The effect of ageing is studied for self-quenching GM counters of differently combined electrode diameters. The results obtained show that: 1) the basic factor contributing to the ageing of a counter is the change of the anode surface area; 2) this change appears in the discharge zone and is developed in three consecutive stages; (a) appearance of a fine powder, (b) appearance of spikes and flakes, and (c) formation of granules situated almost evenly along the anode length. 3) The anode surface could be brought to a state corresponding to a given stage, either through a definite number of recorded pulses, or by a certain intensity of the field, i.e., the change is dependent on the momentum of the products attacking the anode. The investigations are carried out with the purpose of confirming the role of the anode found in our previous papers - this role is basic for the operation of the counter.

2.—The Proportional Counter as a Position-Sensitive Device.

SynopsisThe location of the trajectory of a charged nuclear particle can be determined by a number of devices whose operation depends on characteristics of gas counters operated in the region of proportional energy response. Such devices have advantages in precision, speed or available size over other types of position-sensitive counters. The events may be located by observing pulses on one of a set of closely spaced anode wires in a common gas volume, by measuring the drift time of primary electrons to a particular anode wire, or by determining the location of an electron avalanche along the length of a single anode. The operation of the different types of systems and the factors affecting their precision are described. Precision to less than 1 mm can be obtained in a number of ways,

Fatigue effects on the cathode of self-quenching GM counters

The work functions of Cu and Ni cathode tubes and the plateau length and slope of Geiger-Mueller tubes after prolonged operation were studied. The tubes used were of identical geometry with a cathode diameter of 20 mm, a sensitive anode length of 80 mm, and a gas volume of about 25 cc. All tubes contained a gas mixture of the same composition and pressure throughout the measurements. In the course of fatigue operation the work function of the Ni cathode increases rapidly at first and then gradually the rate of increase becomes slower. The plateau length also shows a sharp increase, but the plateau slope shows a strong decrease. Similar results were obtained for the Cu cathode tubes. (J.S.R.)

A new design of high-power S-band magnetron

A radically new design of S-band magnetron rated at 2.5 MW peak and 3.75 kW mean power is described. This rating is most conservative since twice these powers can usually be obtained. Two important novel features are a long anode and a symmetrical end output. The anode length of 4in, i.e. two to three times the usual length, ensures low cathode loading but introduces additional higher-order axial modes of oscillation. The properties of long anodes are discussed and it is shown that the additional modes may be well separated from the normal modes. The use of a symmetrical output and strict maintenance of mechanical, and hence electrical, symmetry enables strapping to be eliminated, resulting in a magnetron of very simple construction.

A Magnetron-Resonator System

The present exposition deals with the fundamental multiplet spectrum of a multi-sectorial cavity or vane-type magnetron and specific applications involving the evaluation of the π-mode wave-length thereof. The consequence of mutual coupling between the sectorial cavities through the interaction space of an infinitely long anode is evaluated for the linear case and subsequently applied to the cylindrical case. Although both the qualitative and quantitative results are reasonable in the limit for relatively very long anodes, in practice the latter are relatively short and since the mode separation, order thereof, and hence the component wave-lengths are more or less influenced by the actual relative anode and end cavity lengths at each end of the anode, the results naturally differ from ``cold'' test data. Predictions of π-mode wave-length have been obtained to about 10 percent, depending upon the degree to which the parameters of the actual vane magnetron approximate the assumptions on which the present treatment is based. With the aid of ``cold'' test data the preliminary theoretically derived resonator geometry may be appropriately ``trimmed'' to produce the exact π-mode wave-length desired. Included in this article is a discussion of the need and function of straps of the resonator system and dimensional scaling, which preserve certain desirable properties of the prototype at the new wave-length, or operating point, in terms of magnetron performance-chart parameters. Finally, in Part III, a brief consideration is allotted to the derivation of the rectangular cavity or slot-type resonator system from the more general relation for the sectorial cavity in this article.