《【独胆预测】》The direct application of steam to forging-hammers is without doubt the greatest improvement that has ever been made in forging machinery; not only has it simplified operations that were carried on before this invention, but has added many branches, and extended the art of forging to purposes which could never have been attained except for the steam-hammer.
Shrinkage, or the contraction of castings in cooling, is provided for by adding from one-tenth to one-eighth of an inch to each foot in the dimensions of patterns. This is a simple matter, and is accomplished by employing a shrink rule in laying down pattern-drawings  from the figured dimensions of the finished work; such rules are about one-hundredth part longer than the standard scale.A carriage moving on angular ways always moves steadily and easily, without play in any direction until lifted from its bearing, which rarely happens, and its lifting is easily opposed by adjustable gibs. A carriage on a flat shear is apt to have play in a horizontal direction because of the freedom which must exist to secure easy movement. In the case of tracks, it may also be mentioned that the weight of a carriage acts as a constant force to hold it steady, while with a flat shear the weight of a carriage is in a sense opposed to the ways, and has no useful effect in steadying or guiding. The rigidity and steadiness of tool movement is notoriously in favour of triangular tracks, so much so that nearly all American machine tool-makers construct lathes in this manner, although it adds no inconsiderable cost in fitting.
The adaptation, endurance, and cost of machines in designing become resolved into problems of movements, the arrangement of parts, and proportions.
Some hints will now be given relating to apprentice experience in a workshop, such matters being selected as are most likely to be of interest and use to a learner.
3. The saving from condensation, to which steam is exposed, avoidance of heat, and the consequent contraction and expansion of long conducting pipes.
Fourth. Pressure wheels, acting in every respect upon the principle of a rotary steam-engine, except in the differences that arise from operating with an elastic and a non-elastic fluid; the pressure of the water resting continually against the vanes and "abutment," without means of escape except by the rotation of the wheel.
One not accustomed to manual labour will, after commencing, find his limbs aching, his hands sore; he will feel exhausted both at the beginning and at the end of a day's work. These are not dangerous symptoms. He has only to wait until his system is built up so as to sustain this new draught upon its resources, and until nature furnishes a power of endurance, which will in the end be a source of pride, and add a score of years to life. Have plenty of sleep, plenty of plain, substantial food, keep the skin clean and active, laugh at privations, and cultivate a spirit of self-sacrifice and a pride in endurance that will court the hardest and longest efforts. An apprentice who has not the spirit and firmness to endure physical labour, and adapt himself to the conditions of a workshop, should select some pursuit of a nature less aggressive than mechanical engineering.
CHAPTER XXXV. MILLING.
2. The percussive force of spouting water can be fully utilised if its motion is altogether arrested by the vanes of a wheel.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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