Modern turbine wheels have been the subject of the most careful investigation by able engineers, and there is no lack of mathematical data to be referred to and studied after the general principles are understood. The subject, as said, is one of great complicity if followed to detail, and perhaps less useful to a mechanical engineer who does not intend to confine his practice to water-wheels, than other subjects that may be studied with greater advantage. The subject of water-wheels may, indeed, be called an exhausted one that can promise but little return for labour spent upon it—with a view to improvements, at least. The efforts of the ablest hydraulic engineers have not added much to the percentage of useful effect realised by turbine wheels during many years past.
At this point will occur one of those mechanical problems which requires what may be called logical solution. The valve must be moved by the drop; there is no other moving mechanism available; the valve and drop must besides be connected, to insure coincident action, yet the valve requires to move when the drop is still. Proceeding inductively, it is clear that a third agent must be introduced, some part moved by the drop, which will in turn move the valve, but this intermediate agent so arranged that it may continue to move after the hammer-drop has stopped.
A peculiarity of forging is that it is a kind of hand process, where the judgment must continually direct the operations, one blow determining the next, and while pieces forged may be duplicates, there is a lack of uniformity in the manner of producing them. Pieces may be shaped at a white welding heat or at a low red heat, by one or two strong blows or by a dozen lighter blows, the whole being governed by the circumstances of the work as it progresses. A smith may not throughout a whole day repeat an operation precisely in the same manner, nor can he, at the beginning of an operation, tell the length of time required to execute it, nor even the precise manner in which he will perform it. Such conditions are peculiar, and apply to forging alone.
One of the problems connected with the handling of material is to determine where hand-power should stop and motive-power begin—what conditions will justify the erection of cranes, hoists, or tramways, and what conditions will not. Frequent mistakes are made in the application of power when it is not required, especially for handling material; the too common tendency of the present day being to apply power to every purpose where it is possible, without estimating the actual saving that, may be effected. A common impression is that motive power, wherever applied to supplant hand labour in handling material, produces a gain; but in many cases the  fallacy of this will be apparent, when all the conditions are taken into account.Seventh.—There is no waste of power by slipping belts or other frictional contrivances to graduate motion; and finally, there is no machinery to be kept in motion when the hammer is not at work.
Besides this want or difference of facilities which establishments may afford, there is the farther distinction to be made between an engineering establishment and one that is directed to the manufacture of staple articles. This distinction between engineering-works and manufacturing is quite plain to engineers themselves, but in many cases is not so to those who are to enter as apprentices, nor to their friends who advise them. In every case where engagements are made there should be the fullest possible investigation as to the character of the works, not only to protect the learner, but to guard regular engineering establishments in the advantages to be gained by apprentice labour. A machinist or a manufacturer who employs only the muscular strength and the ordinary faculties of workmen in his operations, can afford to pay an apprentice from the beginning a fair share of his earnings; but an engineering-work that projects original plans, generates designs, and assumes risks based upon skill and special knowledge, is very different from a manufactory. To manufacture is to carry on regular processes for converting material; such processes being constantly the same, or approximately so, and such as do not demand much mechanical knowledge on the part of workmen.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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