《新运飞艇是否准确》The auxiliary departments, if disposed about an erecting shop in the centre, should be so arranged that material which has to pass through two or more departments can do so in the order of the processes, and without having to cross the erecting shop. Casting, boring, planing, drilling, and fitting, for example, should follow each other, and the different departments be arranged accordingly; whenever a casting is moved twice over the same course, it shows fault of arrangement and useless expense. The same rule applies to all kinds of material.
A great share of the alleged improvements in machinery, when investigated will be found to consist in nothing more than the combination of several functions in one machine, the novelty of their arrangement leading to an impression of utility and increased effect.CHAPTER XLI. WORKSHOP EXPERIENCE.
These remarks upon hammers are not introduced here as a matter of curiosity, nor with any intention of following mechanical principles beyond where they will explain actual manipulation, but as a means of directing attention to percussive acting machines generally, with which forging processes, as before explained, have an intimate connection.
(1.) What analogy may be found between steam and water power?—(2.) What is the derivation of the name turbine?—(3.) To what class of water-wheels is this name applicable?—(4.) How may water-wheels be classified?—(5.) Upon what principle does a reaction water-wheel operate?—(6.) Can ponderable weight and pressure be independently considered in the case?—(7.) Why cannot radial running joints be maintained in machines?—(8.) Describe the mechanism in common use for sustaining the weight of turbine wheels, and the thrust of propeller shafts.Ordinary machinery, on the reverse, is stationary, generally consumes a regular amount of power, is not subjected to such uncertain strains, and as a rule acts without its operation being controlled by the will of attendants.
Presuming an engineering establishment to consist of one-storey buildings, and the main operations to be conducted on the ground level, the only vertical lifting to be performed will be in the erecting room, where the parts of machines are assembled. This room should be reached in every part by over-head travelling cranes, that cannot only be used in turning, moving, and placing the work, but in loading it upon cars or waggons. One result of the employment of over-head travelling cranes, often overlooked, is a saving of floor-room; in ordinary fitting, from one-third more to twice the number of workmen will find room in an erecting shop if a travelling-crane is employed, the difference being that, in moving pieces they may pass over the top of other pieces instead of requiring long open passages on the floor. So marked is this saving of room effected by over-head cranes, that in England, where they are generally employed, handling is not only less expensive and quicker, but the area of erecting floors is usually one-half as much as in America, where travelling-cranes are not employed.
Besides the machine tools named, there are special machines to be found in most works, machines directed to the performance of certain work; by a particular adaptation such machines are rendered more effective, but they are by such adaptation unfitted for general purposes.
Civil engineering, in the meaning assumed for the term, has become almost a pure mathematical science. Constants are proved and established for nearly every computation; the strength and durability of materials, from long and repeated tests, has come to be well understood; and as in the case of machine tools, the uniformity of practice among civil engineers, and the perfection of their works, attest how far civil engineering has become a true science, and proves that the principles involved in the construction of permanent works are well understood.
To master the various details of machine manufacture, including draughting, founding, forging, and fitting, is of itself a work equal to most professional pursuits, to say nothing of manual skill; and when we come to add machine functions and their application, generating and transmitting power, with other things that will necessarily be included in practice, the task assumes proportions that makes it appear a hopeless one. Besides, the work of keeping progress with the mechanic arts calls for a continual accretion of knowledge; and it is no small labour to keep informed of the continual changes and improvements that are going on in all parts of the world, which may at any time modify and change both machines and processes. But few men, even under the most favourable conditions, have been able to qualify themselves as competent mechanical engineers sooner than at forty years of age.To point out some of the leading points or conditions to be taken into account in pattern-making, and which must be understood in order to manage this department, I will refer to them in consecutive order.Institute of Plasma Physics, Hefei Institutes of Physical Science (ASIPP, HFIPS) undertakes the procurement package of superconducting conductors, correction coil, superconducting feeder, power supply and diagnosis, accounting for nearly 80% of China's ITER procurement package.
"I am so proud of our team and it’s a great pleasure for me working here," said BAO Liman, an engineer from ASIPP, HFIPS, who was invited to sit near Chinese National flay on the podium at the kick-off ceremony to represent Chinese team. BAO, with some 30 ASIPP engineers, has been working in ITER Tokamak department for more than ten years. Due to the suspended international traveling by COVID-19, most of the Chinese people who are engaged in ITER construction celebrated this important moment at home through live broadcasting.
One of ASIPP’s undertakes, the number 6 poloidal field superconducting coil (or PF6 coil) , the heaviest superconducting coil in the world, was completed last year, and arrived at ITER site this June. PF6 timely manufacturing and delivery made a solid foundation for ITER sub-assembly, it will be installed at the bottom of the ITER cryostat.
Last year, a China-France Consortium in which ASIPP takes a part has won the bid of the first ITER Tokamak Assembly task, TAC-1, a core and important part of the ITER Tokamak assembly.
Exactly as Bernard BIGOT, Director-General of ITER Organization, commented at a press conference after the ceremony, Chinese team was highly regarded for what they have done to ITER project with excellent completion of procurement package.
The kick-off ceremony for ITER assembly (Image by Pierre Genevier-Tarel-ITER Organization)
the number 6 poloidal field superconducting coil (Image by ASIPP, HFIPS)
ITER-TAC1 Contract Signing Ceremony (Image by ASIPP, HFIPS)
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