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The writer invented the improved Vat for a cylinder paper machine for making paper with high speed. The construction and the method is as follows : in front of the cylinder moved, a head-box is fitted higher, with a nozzle at the outlet over the width of cylinder face, whose lip is capable to adjust in opening. With a suitable high speed, made by the hydraulic head standing in the head-box, the stuff stream rushes into the stuff pool and agitates uniformly the stuff before the eylinder mould. And at the instant, the cylinder picks the fibres from the stuff on its surfaee, making good even paper web. (Pat, applied in Japan)

THE HISTORY of the paper industry and the history of paper machine drives is a story of continued progress; progress in improved performance, increased reliability, and operator convenience.

The basic criteria for development of a suitable per cent moisture gauge for paper are discussed and the paper industry requirements analysed. The theory of operation for the infra-red gauge is explained and the various components of the system described at length. Installation methods for fixed point and traversing mechanisms are set forth. The significance of the calibration technique being used is discussed. A wide range of current installations is described and the extension of applications on the paper machine suggested.

THE requirements for electric power-in modern pulp and paper mills are increasing at greater rates than the requirements for thermal power. In consequence, the electric power that can be generated by the normal flow rate of process steam is becoming inadequate. Low-cost hogged fuel and mill waste are also no longer available in abundant quantities to generate the increasing unbalance in electric load with condensing steam. Therefore, mill operators are finding it more economical to purchase a portion of their electric energy from utility power systems rather than to operate their own generating equipment on more expensive fuels and with consequent heat loss to the condensing water.

A method has been developed for economically manufacturing insulated wire for telephone exchange area cable by making the paper on the wire. Further, this method has made it possible to increase the number of wires in a full sized cable by 175% over the number in use in 1914. Developments now under way indicate that suitable insulation can be made to replace certain textiles in some classes of wire and that the use of this process may therefore be still further extended in the not so distant future.

This paper describes the design, manufacture and tests on a 500/550 kV cable and joint. The cable successfully withstood 1550 kV impulse and 1290 kV switching surge established by Electric Research Council for the Waltz Mill field tests. The 60 Hz tests demonstrated the cable with either a splice, insulated to 2 times the insulation O.D. or 1.5 times the insulation O.D. had adequate ac dielectric strength.

ONE of the most pressing problems in modern life is the construction and maintenance of an adequate system of highways. It is evident that the need is great for more new highways and, equally important, they must be constructed in the most durable manner possible.

Chipper drive is one of the most exacting applications to which motors are applied. The size of the motor is determined primarily by the high peak loads which occur intermittently when large logs are fed. Motors for this application must be made mechanically stronger than standard to withstand the shock loads and vibration imposed by the chipper.

The Hot-Wire Anemometer Paper Tape Reader was conceived as a relatively simple apparatus to serve as a high reliability device such as required in peripheral computation equipment. The hot-wire anemometer principle has been employed extensively in the past for the study of transient air flow phenomena in compressors and turbines. The principle of operation concerns an electrically heated wire used to detect a change in air velocity in its immediate vicinity by observing its change in temperature and consequent change in resistance. Using this principle to read perforated members such as punched paper tape at high speeds offers a number of distinct advantages over conventional reading methods.

The Paper-Tape-to-Magnetic-Tape Converter consists of two racks of electronic equipment whose function is to transcribe seven-channel digital code on punched paper tape to seven-digital code on magnetic tape in a form compatible with the input requirements of the IBM 704 and 709 computers. Recording is accomplished by electronically controlling the "read" and "stop" modes of the paper tape reader while the magnetic tape continuously advances. The converter also checks for certain types of error in the structure of the coded information on the paper tape and indicates their presence. The encoded magnetic tape is used as the information input to a properly programmed IBM computer. (auth)

Insulation paper is primarily used in electric motors as slot cells, coil separators and phase insulation in integral horsepower equipment. The slot cell being defined as the basic ground insulation that provides mechanical and dielectric barriers from the magnet wire to the stator core. This definition emphasizes that the insulation paper forming the slot cell is mainly ground insulation.

Publisher Summary This chapter presents experiments on deformations of paper in stacks, in which sheets were conditioned at a fixed humidity and then printed with a screen line plate by means of a Vandercook proof press. The prints were stacked progressively during printing. The stack was exposed to another humidity for a time and then, a second color was printed upon the first one, from the same plate. From the interference of the two line patterns, it was possible to measure deformation of the paper. Every sheet was measured and the results for an offset paper, a conventional coated paper, and a machine-coated paper are presented in the chapter. The change in dimension is given on the abscissa in units of 0.1 mm/m. The trials were made on three papers: (1) an offset paper, (2) a conventional coated paper, and (3) a machine-coated paper. The results show that the deformation was greater in the transverse direction than in the longitudinal direction and the deformations were not the same whether the transverse direction or the longitudinal direction was parallel to the cylinder axis; this effect shows that the press has a laminating action.

This document constitutes the final in a series covering the development of a continuous carbon paper facsimile recorder. The recorder, is designed for fixed station use in the reception of both weather and message type information and is capable of reproducing copy sent from a remote point by accepting facsimile signals over wire or radio hook-up. For the latter mode of operation, a receiver-converter is used. Operation is directly from a 115-volt, 60-cp power line.

Consideration is directed toward electromagnetic compatibility as viewed from the control aspect. Emphasis is placed upon an inter-system approach to the improvement of the over-all electromagnetic environment.

During the past five or six years, practically all of the American cable manufacturers have made some changes in their impregnating compound so as to produce cable having a low dielectric loss. In a number of cases, these compounds were not well chosen. During the same period, some of the operating companies have reduced the thickness of their insulation, resulting in increased dielectric stresses. In a number of cases, the compounds and perhaps also the paper that was used developed faults that were more serious than high dielectric loss. Some cables have been very deficient in dielectric strength and others have developed a new type of trouble which has been termed ``ionization'' and, after a comparatively short time, the operating voltage of such cable had to be materially reduced in order to keep the lines in service or the cable had to be replaced. The cable manufactured during this period has generally passed, with a wide margin, the high voltage tests required by the specification. Occasionally a lot of cable which passes these tests by a narrow margin will be shipped by a manufacturer and, in such cases, the service record of the cable is unsatisfactory. The investigations which form the basis of this paper consist of: (a) Laboratory tests to determine what high-voltage tests cable known to be of good quality will withstand as well as the similar tests on other grades of cable.

For many years shellac or synthetic-resin-coated paper has been used in winding condenser bushings. Two years ago work on the development of oil-impregnated-paper condenser bushings was undertaken. When a shortage of shellac was imminent because of the war, effort to complete the development was greatly increased, resulting in its being completed well ahead of the date originally set. Manufacturing processes and impregnating treatments were developed and bushings built and tested. The processes and treatments are described, and the data obtained from tests on representative bushings are given. Complete interchangeability for transformer and circuit-breaker bushings has been obtained for current apparatus designs in the voltage ratings in which the bushings are produced. To a large extent, the new bushings are also interchangeable with bushings of older design in the same voltage rating. The entire insulating portion of the bushing is enclosed in porcelain and metal and this enables the bushing to be held in storage without special provisions for keeping it dry. The oil-impregnated-paper condenser bushings, built for voltage ratings 92 kv to 230 kv, are susceptible to careful control of quality in the processing operations. Exceptionally consistent performance and high dielectric strength are obtained. Consistently low power-factor readings on both hot and cold bushings were obtained. Radio-influence voltage measurements were below proposed standards.

The ever increasing speeds of paper-making machines has made necessary the replacement of the inadequate mechanical drive with electrical sectional drive, and the perfection acquired in modern electrical sectional paper-machine drive has made possible unlimited paper speed in so far as the drive and control is concerned. Not only is electrical sectional drive necessary for high speed machines but it is highly economical for even the slowest speed machines on account of the saving in power over mechanical drive, the great saving in maintenance, and the greater precision with which the section speeds can be maintained thereby greatly reducing the number of paper breaks and increasing production. This paper outlines the several trends of development in an historical sketch of progress in the art up to the present time, devoting special attention to a unique system of direct current drive in which the section driving motors through a differential electrical field control means, cause the several section driving motors to operate in synchronous relation at any desired relative speed values, which speed relations are at the same time adjustable at the will of the operator.

This paper deals with the effect of errors in the measurement of power factor upon the usefulness of impregnated paper-insulated cables. It points to error in the knowledge of the thermal properties of the cable and the cable duct. The latter error affects the usefulness of a cable to such an extent as to permit a limited error in the power factor without materially reducing the efficiency of the cable. This limited error defines the required power-factor accuracy. The required power-factor accuracy in general is found to vary directly with the frequency and the specific inductive capacity of the insulation, and to increase with the number of cables in a duct bank and the ratio of E2/G, where E is the operating voltage of the cable in kilovolts and G is the geometric factor. For very high-voltage single-conductor cables the power-factor accuracy should be within the order of 0.002.

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A new technique of cable examination has been developed. Incipient faults have been studied before actual breakdown with the aid of a microscope, the papers having been freed from oil and dyed to show up the waxing. The types of waxing observed are classified, and their part in breakdown is discussed. The deterioration is always found to be in connection with the conductor, generally through the gap of the first paper. The occurrence of the maximum deterioration at a distance from the conductor is explained, and a diagram showing the path of failure in an actual case is given. The conclusion reached is that failure originates from the ionization in a void in contact with the conductor, but that subsequent breakdown takes place by carbonization of the compound. Such carbonization requires time for its completion and is the chief factor in the voltage/time-to-breakdown curve. It takes place both longitudinally, over the surface of the paper, and perpendicularly through it. The results obtained in the laboratory are compared with those in service, and the types of failure are described. The effect of d. c. stress on cables is discussed and the advantages of routine d. c. testing of feeders are explained on this basis.

In 1924 two papers were presented before the A. I.E. E. on Turbo Alternator Ventilation. In one of the papers tests on two models for two methods of ventilation were described, and data from the tests were given. The other paper contained a mathematical treatment for one system of ventilation, which was based upon the data obtained from the tests. It was recognized that the tests were not sufficiently accurate to evaluate the loss coefficients, nor was it possible to obtain data on the distribution of volumes for the intake vents. For that system, (see Fig. 1), it was found that the influence of rotation upon total volumes and their distribution could be neglected; consequently the investigation could be continued on stationary models. Those tests, the methods of determining the losses and the equations derived therefrom are given in this paper. Since the effect of rotation could be neglected, the test could be reduced to a model which represented only one axial row of vent ducts. On this model the stator vent ducts were imitated by square brass tubes with a plaster of paris restriction cast in one end to imitate the vent duct restriction so that the pressure drop obtained for either direction of flow was approximately the same as in a stator vent. A long steel channel or duct represented the section of the air-gap. Some of these brass tubes, representing intake vents, lead from a large sheet metal box to the gap channel. Other tubes, representing discharge vents, lead from the gap channel to the atmosphere. The gap channels could be inter-changed readily to represent various sizes of air-gaps. Any desired number of intake and discharge tubes could be used so as to represent any desired layout of the machine. The volumes in individual intake tubes were measured by reading on a manometer the drop in pressure from the intake chamber to a point a little ways down the tube. For the discharge tubes small impact tubes were employed. Each tube was carefully calibrated before making any other tests; a thermal volume meter was used for calibrating an orifice, and the orifice was used for the lube calibrations. Various difficulties arose, and the means of overcoming them are given. Tests were made with a group of intake vents, and the losses were separated into (1) those in the tubes; (2) those accompanying a right angle turn; (3) those due to a stream of one velocity impinging upon a stream of another velocity; (4) those due to sudden increase in velocity; (5) those due to surface frictions. Similar tests on the discharge side showed that the losses there could be separated into (1) those in the tubes; (2) those accompanying a right angle turn; (3) those due to sudden decrease in velocity; (4) those due to surface friction. The losses were put, for the most part, into comparatively simple expressions. They were then combined in order to obtain final solutions. There was no difficulty on the intake side in obtaining a differential equation which admitted of ready integration. On the discharge side, however, it was necessary to use approximations. With the aid of the final equations the total volumes and their distribution can be calculated for a given pressure drop. One difficulty is that the equations include trigonometric and hyperbolic functions of quantities involving the distance between the point where the gap velocity is maximum to the points where the gap velocity is zero. The latter point, called the “balance point” is not known, and a simultaneous solution of the transcendental equations needed for its determination, is impossible. Suggestions for a direct simple approximate solution are given, which may be followed by trial and error methods. In most of the applications, only one or two trials were required. The equations were checked for accuracy by comparison with tests made on the tubes, on the turbo model of 1922 and 1923, and with those on an actual machine. The agreement in total volumes was very close, and is considered to be quite good for distribution also.

Data are presented on impulse-voltage breakdown values obtained on oil-treated paper-insulated cables over the insulation thickness range from 0.187 inch to 0.600 inch. The average stress at breakdown approximates 1,600–1,700 volts per mil. High-density papers show some superiority over ordinary-density papers. Cathode-ray oscillograms of the testing wave (1½x40 impulse wave — positive polarity) before and at breakdown are included for a typical test.

This paper reviews the installation of automatic transmissions into vehicles, and the matching calibration of the transmission and converters to various types of engines and vehicles. Bench and field acceptance testing, with some reference to transmission manufacturers' approval of fluid and materials, are also discussed, and unorthodox automatic transmissions such as transaxle in-line and transverse, are reviewed. The paper finally examines volume production techniques of today's automatic transmissions and presents some remarks on future trends and requirements.

Measurement of air permeability of paper less than a few seconds is unavoidablly subject to a great deal of error so far as the use of hand-operated stop watch. So we developed an automatic permeability tester using a electric second-watch and a light-relay device. It is confirmed that using the device described, which enables one to test on one-sheet basis instead of using as test proof numerous sheets put together in layer, the exactitude in time of measurement for papers of high air permeability can be improved to a great extent.

In summary, there has been described an Outscriber which, using a modified Western Union 3-stylus Teledeltos recorder in conjunction with the required accessory electronic and mechanical equipment, is capable of printing, in a binary presentation, 80,000 bits per minute. The record is in the form of two 40-bit words per line, and 1000 lines per minute. Each line of data may, if desired, be reprinted up to 8 consecutive times in order to give immunity against statistical fluctuations in the paper characteristics and in the operation of the device. A record containing 1,024 words, where each of the 512 lines has been printed one time, is included on a piece of Teledeltos paper 8-1/4'' by 19''. After there is deducted from this area of paper the 1-5/8'' of width for the edge and center margins, the figure of merit for this device is found to be 320 bits per square inch per unit time.

A significant and interesting difference between American and European practice in the manufacture of mass-impregnated paper-insulated cables for low and medium voltage is that, while in Europe oil-rosin compounds are widely used as the saturant, in the United States straight oils or hydrocarbon blends with oils find the widest application, and rosin compounds are not favored. The author considers this difference in techniques to be of sufficient interest to warrant investigation, and the European viewpoint supporting the use of oil and rosin blends is presented in this paper. In recent years wax-bearing compounds have been developed for the mass impregnation of cables required to be nondraining in service. These cables are finding ever-increasing markets for voltages up to 11 kv. Oilostatic cables, which are favored in the United States, are not widely used in Europe for operation at the higher voltages, for which hollow-core or gas pressure designs are preferred. The characteristics of oils for these applications are discussed. Much of the material supports and corroborates the work of previous investigators (see the list of references).

In this paper discussed neccessity of paper thickness measurements and introduced several electric thickness meters, static capacity method, electromagnetic method.In the next place, described the principle, construction and characteristics of ETL type meter by electromagnetic induction method.By practical experiment this method are discoverd that can be continuous recording and nondestructive indication.

FOR many years engineers have been concerned to find what the factors are that bear on and control the dielectric strength of electric cable insulating papers. Among the well-known factors investigated is the paper's density which, in most instances, has been inextricably intertwined with the paper's air resistance. As far as the authors of this article are aware, no serious attempt has been made yet to separate the influence of air resistance as a single factor. It is the belief of the authors that they have succeeded in making this separation.

Design and performance of a low-noise down converter and a high-efficiency up converter for transmitter-receiver applications in the frequency range of 60-86 GHz are described in this short paper. The receiver and the transmitter are used in a guided millimeter-wave transmission system "W-40G" A wafer-type GaAs Schottky-barrier diode is used in both units. The diode mount consists of a semiconductor wafer and a whisker which are mounted in a waveguide circuit. The IF terminal is a coaxial line section which is connected to the whisker. The conversion loss of the up and down converters using the new wafer is 7.5 and 5.5 dB, respectively. The bandwidth of the frequency converters is approximately /spl plusmn/10 percent in the frequency region of 60-86 GHz.

Mr Lines opened his address by introducing the Aerodist and explaining briefly some later modifications not mentioned in his paper. He said that the Division of National Mapping had recently acquired another Master Station and one more remote station making a total of three Masters and six Remotes. A brief mention was made of a remote station now being modified for dual frequency operation.

Careful analysis of the characteristics of a power system has been found to be necessary before applying Petersen coils to a system which has been operating either with the neutral isolated or grounded. In these two companion papers on Petersen coils, accent has been placed on the analysis of system characteristics in order to determine whether or not the application of Petersen coils will be satisfactory.

This paper covers General Cable Corporation's development and testing of a 500 KV high pressure pipe type oil filled cable. It also covers the installation of a sample length of this cable at the Edison Electric Institute test site at Waltz Mill, Pennsylvania.

The usual methods of testing alternating-current high-voltage paper-insulated cables are based upon the ability of the insulating material to withstand excessive potentials in order to determine its condition. Accordingly, these methods are not suitable for routine tests imposed for the purpose of determining the degree of deterioration existing in any particular cable. In an effort to develop a routine test, which will serve to detect an impending fault, use has been made of the kenotron as the source of high-potential direct-current. By means of it a large volume of data has been secured concerning the input-current, for a cable, as a function of time after complete electrification at a constant high potential. These data when plotted, as curves, show by their shape the condition of the cable insulation. Curves showing a sharp decrease in the magnitude of input-current during the first minute and a gradual but persistent rate of decay for the succeeding six or seven minutes indicate that the insulation is in an acceptable condition from the operating point of view. Curves showing little, if any, decrease or a persistent tendency to increase during the time interval of the test indicate that the insulation has deteriorated to such a point that the cable may be expected to fail at an early date if retained in service. The degree of deterioration is indicated first: by the time which has elapsed since complete electrification before the increase occurrs, and second: by the sharpness of the upward trend of the curve in any instance. The value of this method of testing has been demonstrated by its actually having detected a considerable number of impending cable faults before they became a menace in operation. Additional refinements in the methods of measuring the input-current for different classes of cables may be desirable. Further investigations are being carried on to determine this necessity. Investigations of certain theoretical features are also being carried on. These include, among other things, oscillographic studies of the input-current and voltage under test conditions.

The noise produced by the circulating water pump motors at Blyth ‘B’ power station contained a pure tone and this led to complaints both from the public and from the plant attendants. It was established that the noise was principally magnetic in origin, attributable to an unfavourable combination of numbers of stator and rotor slots, and the noise level was reduced by modifying the design of the rotor to obtain a better slot ratio. The noise level was still undesirably high, however, and an experimental silencer for the cooling air inlets and outlets was designed and a mock-up constructed of timber, hardboard, and mineral wool slab. These combined measures reduced the noise inside the pumphouse to well within the ISO noise rating number 85, which has been taken as the hearing damage risk criterion, and abated the public annoyance outside the pumphouse. This paper describes the basic origin of magnetic noise in squirrel-cage motors and methods for controlling noise levels both by design of motor and silencers within the limits set by electrical and economic design parameters.

This report deals with an investigation of eddy-current losses in multi-core circular-conductor and shaped-conductor paper-insulated wire-armoured cables, and the development of formulae by means of which the losses can be computed. The experimental work covers tests with balanced three-phase currents at frequencies from 25 to 300 cycles per second. The eddy-current losses are divided into four parts, namely, skin effect, proximity effect, lead-sheath effect, and armouring effect. The ratio of a.c. to d.c. resistance of the conductors, calculated by the appropriate formula, is, with one exception, within 5% of the measured value under all the conditions covered by the investigation, the average difference between calculation and measurement being only 1%.

A. E. Kennelly: Turning to the paper by Dawes and Hoover, it seems to me that the great force of that contribution lies in the fact that a bridge has been developed which employs a vibration galvanometer, with all the delicacy and precision that the vibration galvanometer affords, so that instead of having to employ a relatively great length of cable dielectric for test, it is sufficient to have only, say, a couple of meters, provided that the particular couple of meters shall represent fairly well, the whole length of a cable under consideration.

The purpose of this short paper is to give an exact theory of quarter-wave coupled circulators with Chebyshev characteristics. The synthesis starts by replacing the lumped-element equivalent shunt resonator of the circulator by a distributed one that has the same susceptance slope parameter as the original circuit. In this way the overall network involves commensurate transmission lines only. The bandwidth over which the assumed form of the equivalent circuit applies is carefully discussed in terms of the two split frequencies of the magnetized junction. Tables for the required circulator parameters and transformer admittances for one and two transformer sections as a function of VSWR and bandwidth are included. The realizable solution for the latter arrangement is severely restricted by the equivalent circuit of the basic junction. Experimental results on an octave-band stripline circulator, with a two-section transformer, are also included.

THE capital investment in the underground cable system of any large metropolitan utility is so great that any means of increasing its usefulness is of great and immediate interest. The operation of paper-insulated cables at higher copper temperatures than are accepted as normal, offers one obvious means of increasing the usefulness of the cable system where voltage regulation does not limit load.

Shortage of independent control signals limits the ‘cleverness’ of externally powered limbs. Surface methods of sensing muscle activity give very crude reproduction. Implanted sensors ought to extract some of the untapped skill of muscles, and help establish how it may be applied. The Emgor is a sensor for myoelectric signals which is intended to be permanently implantable, with this aim in view. The paper describes the sensor and its associated electronics, and gives details of its performance.

Over the last 15 years the synchronous drive belt has become an established part of the power transmission scene. It is not a direct substitute for any of the more traditional transmission media; the unique properties of the belt make it complementary to them. This paper describes the current state of the art mainly from an industrial application point of view. This approach necessarily includes certain production information and the background to the power rating table.

Experiments have been undertaken at selected electrical loads on a self-contained turbo-alternator set comprising a 350-kW 60-c/s alternator driven by means of double helical parallel shaft gearing by a high-speed (15 000 rev/min) steam turbine. The turbo-alternator was erected on flexible mountings with all steam, water, and other service connections arranged in such a manner that they placed no constraint on the machine. In addition to the turbine and alternator rotors several auxiliary drives each contribute to the total noise output. These include the d.c. exciter, pilot exciter, and metadyne unit which are driven directly, or by belts, from the alternator shaft and the oil pumps, governor, etc., which are driven from the turbine shaft by way of spur and bevel gears. The paper describes the manner in which the separate effects of each of the major sources of structural vibration and airborne noise were isolated and measured. In-place balancing techniques were employed to aid an investigation of the variation of vibration level with rotor out-of-balance. In the process experimental information was obtained about the damping effects of journal bearing oil films, vibration amplitudes of the bearing housing being as much as 25 dB below the equivalent shaft amplitudes.

This paper discusses briefly the concept of a highly rated steam turbine, making use of the well-known laws of dynamic similarity, and demonstrates the economic advantages of using highly rated machines in appropriate circumstances. A number of design and constructional features of highly rated modern turbines are described and illustrated, together with examples of complete machines. Operational and control aspects and solutions to a number of special problems are discussed.