Various Types Of Machines Research Articles

Design of Extrusion Augers and the Characteristic Equation of Ceramic Extrusion Machines

Since the invention of the auger‐type extrusion machine, there has developed a large business devoted to the production of extrusion machines of various types and sizes for the ceramic industry. During this time, a vast body of empirical knowledge concerning the design of augers, dies, and machines to do particular jobs has grown. As of today, no method has been proposed by which values may be assigned to the design parameters of an auger so that there may be reasonable assurance that it will extrude a material, the plastic properties of which may be known. This paper proposes a model for the operation of an auger on a material and adapts the theory of the screw conveying of solids in organic thermoplastic extrusion machines to the study of this model. The concept of the characteristic function, which describes the action of a particular extruder on a plastic material, is discussed.

Mechanics of self-reproduction.

SummaryThe construction of various types of machines which can be automatically self‐reproducing, in a sense derived from von Neumann, has been outlined. The features, which any such machine must possess, have been discussed and their possible significance in the understanding of DNA replication has been indicated.I am much indebted to Dr C. A. B. Smith for his valuable suggestions in the interest of making this paper comprehensible, and to Mr A. J. Lee for his admirable drawings.

Resistance-Welding Machine and Power Supply

The final selection of welding equipment must have the following considerations: 1. The ability of the equipment to weld the specified material. 2. The cost of the equipment. 3. The voltage regulation imposed on the supply system by various types of machines. 4. The cost of reinforcement of the present supply system versus the cost of the machines and their correction devices. 5. The total of machines involved and their diversity factor. 6. The rate of production of one system versus another keeping in mind the limitations of each system and the number of machines involved. The a-c single-phase machine is generally found the most economical if the power supply is adequate, if not, a complete study must be made of the total installation and the power system before recommendation of any certain type of machine and its correction device versus power-system reinforcement.

Mechanization of Foundries

The paper describes the principal operations in mechanical moulding plants and makes special reference to the various types of machines for different classes of work; the preparation, reconditioning, and transportation of sand, mould conveying, pouring, and knocking-out; and means for the return of the empty boxes to the moulding machines. The author gives information derived from his practical experience in connexion with mechanized foundry plant. He discusses in detail the respective merits of various methods of mechanical moulding, and contrasts the jolting method with ordinary “straight pressure” moulding. Under-sand frame ramming is also described. Reference is made to the improvements in working conditions which can be effected by mechanization and by proper ventilation at the knocking-out station. Finally, the author describes a number of examples of mechanized or semi-mechanized foundries, and shows how mechanization can be applied even to quite small plants.

Problems and Trends in Centrifugal-Machine Applications

Abstract The paper deals with the factors that govern the design and choice of a centrifugal machine for some specific application so that a prospective user or purchaser may appreciate the scope of the problems involved in the construction of a machine that would meet his requirements. The article describes the various types of machines that are available and specifically calls attention to the newer types of development not generally known. The author surveys the trends in centrifugal-machine development and endeavors to indicate to manufacturers, prospective inventors, developers, and users of these machines the direction in which the art may be extended and expanded by the judicious choice and application of new materials, drives, and methods of construction, as a means of securing maximum production with required safety.

Textile Machinery for the Production of Worsted Yarn

The paper reviews the following operations in worsted yarn production: wool combing and its evolution, with descriptions of the Lister, Noble, and Heilmann machines; worsted drawing on the Bradford, Continental, and Anglo-Continental systems; gilling, with an account of the various types of machine in use; spinning and its evolution, with descriptions of worsted, flyer cap, and ring frames, and of the mule; and the evolution of automatic doffers.

Relation between Theory, Experiment, and Practice in Journal Bearing Design

The first section of the paper is devoted to the correlation of experimental and theoretical research on journal bearings embracing the angles of 360 deg., 180 deg., and 120 deg., and attempts to combine hitherto isolated experimental data by making use of the results of Kingsbury's experiments based upon an electrical analogy. The possible causes of divergence in the results obtained by different workers are enumerated and their effect on the general agreement explained. There is considerable experimental evidence to support the basic principles of the method of design derived in the preceding paper by Dr. Swift.The second section analyses current methods of design in the light of these principles, and explains the reasons for departure from the theoretical method in some cases. Particulars relating to journal bearings used in various types of machines are tabulated, and values of the dimensionless criteria used in actual practice are compared with those suggested by theory. Design examples are worked out, and results tabulated, in order to explain the methods which may be employed in order to secure optimum running conditions in various circumstances, and their resultant effect on performance.A summary is given in the last section of the existing state of knowledge relating to journal bearings, considered from the point of view of the designer. Further data still necessary are enumerated and the avenues of research yet to be explored in order to obtain this knowledge are explained.

Jute and Jute Spinning. Part 1: Production of Fibre; Cultivation, Batching, Preparing and Carding

THESE two volumes form a very welcome addition to textile literature. The authors have a thorough grasp of their subject and a sympathetic understanding of the needs of students. As text-books, the student of jute spinning will find them most comprehensive. Very few text-books on textile subjects cover the ground so completely. The practical man will also have a most reliable source of reference, as the various types of machines and workings have been described and discussed in detail. The subject matter is well arranged and the wealth of detail is presented in a manner that makes the reading of it most interesting. This latter is in itself no mean accomplishment. The line drawings are very clear, and the value of the work has been enhanced by the inclusion of photographs that in many cases were taken in the mills. Practically everything possible has been done to explain the principles underlying the various operations. Jute and Jute Spinning. Part 1: Production of Fibre; Cultivation, Batching, Preparing and Carding. By Thomas Woodhouse Peter Kilgour. Second edition. Pp. xx + 301 + 21 plates. 20s. net. Part 2: Drawing and Roving Frames. By Thomas Woodhouse and Peter Kilgour. Pp. xxiv + 350 + 19 plates. (London: Macmillan and Co., Ltd., 1929.) 20s. net.

A Machine for Making Creep Tests at High Temperatures

Abstract The demand for materials suitable for operation under stress at high temperatures has made it necessary to investigate the properties of various alloys with regard to their resistance to creep. Various types of machines have been developed for this purpose. This paper describes the apparatus developed by the Union Carbide and Carbon Research Laboratories. Its principal features are a compound lever system of applying the load, similar to that used in regular tensile machines, and a simplified method of measuring the extension of the specimens. The compound lever system makes it possible to determine the load accurately and to use standard 0.505-in. diameter specimens without employing excessive weights, even at relatively low temperatures. The system used for measuring extension is such that the construction of the machine is simplified and the convenience of operation improved. The accuracy is ample for all creep tests except those in which extremely small creeps over long periods of time must be measured.

Automatic Control of Edison Systems As Applied in the St. Charles Street Substation of the Union Electric Light and Power Company

A brief description of the Edison System at St. Louis is given, and power supply, service restoration, and system balance are discussed. The history of the application of automatic control equipment to the system and a brief resume of operating experiences are also given. The relation of the St. Charles St. Substation to the remainder of the system is pointed out and certain features of its design explained. The scheme of loading the machines and the method of load shifting between machines is given in detail, and a table is given to show the ``set-up'' for any load. The distinctive features of the various types of machines at this station are discussed, particular attention being given to the control of the converter with transformer taps and high-voltage revolving field booster. The scheme of automatically changing taps under load is described fully. A brief summary of the protective features on this machine is also given. The operating experience with the automatic equipment at the St. Charles St. Station is related.

Abridgment of automatic control of Edison systems: As applied in the St. Charles street substation of the Union Electric Light and Power company

A brief description of the Edison System at St. Louis is given, and power supply, service restoration, and system balance are discussed. The relation of the St. Charles St. Substation to the remainder of the system is pointed out and certain features of its design explained. The scheme of loading the machines and the method of load shifting between machines is given in detail. The distinctive features of the various types of machines at this station are discussed, particular attention being given to the control of the converter with transformer taps and high-voltage revolving field booster. The scheme of automatically changing taps under load is described fully. A brief summary of the protective features on this machine is also given. The operating experience with the automatic equipment at the St. Charles St. Station is related.

Application of electricity to the ore handling industry

The paper gives a general description of the typical method of handling ore from the mine to the blast furnace, describing in a general way the machinery used in the different steps of the process. The general principles underlying the application of electric motors to these various types of machines are discussed, as well as the class of motors best adapted to the work and the considerations in regard to the power installation. The essential points to be considered are; 1, the determination of the shortest path over which the ore is to travel; 2, the determination of the characteristics of the loads in moving ore through this path; 3, the designing of the electrical equipment to carry these loads with minimum peak and maximum reliability, and 4, installation of a substation that will handle the load satisfactorily and most economically, considering both demand charges and the total kilowatt-hours used.

Application of Electricity to the Ore Handling Industry

The paper gives a general description of the typical method of handling ore from the mine to the blast furnace, describing in a general way the machinery used in the different steps of the process. The general principles underlying the application of electric motors to these various types of machines are discussed, as well as the class of motors best adapted to the work and the considerations in regard to the power installation. The essential points to be considered are: 1, the determination of the shortest path over which the ore is to travel; 2, the determination of the characteristics of the loads in moving ore through this path; 3, the designing of the electrical equipment to carry these loads with minimum peak and maximum reliability, and 4, installation of a substation that will handle the load satisfactorily and most economically, considering both demand charges and the total kilowatt-hours used.