Abstract: A pure steam-related apparatus, which is one of apparatus in the group of pure steam generators generating pure steam from purified water, pipelines for pure steam and sterilizers using pure steam, is protected from discoloration, so-called "fouling", to red or black caused by contact with the pure steam. The apparatus is manufactured by using an austenitic stainless steel sheet as the material, by taking the blanks from the material which received no mechanical surface polishing, by deforming and welding, without electrolytic polishing customarily done, and by passivating the surface to contact pure water to increase Cr-content in the passivation film to such extent as 45 atomic % or higher, preferably 55 atomic % or higher. Better results will be obtained by ensuring Cr/Fe ratio in the passivation film at the level of 1.45 or higher, preferably, 1.70 or higher.

Abstract: A precision machining system for machining a workpiece into a desired surface with two tool driving units. A first drive unit moves the tool along at least two axes to shape the workpiece similar to a desired surface. A second drive unit moves the tool along one of the axes in a very finely controlled manner. A measuring unit measures the tool position with an accuracy higher than that to which the first drive unit can respond. A signal producing unit is responsive to the measuring unit for producing a control signal for controlling the operation of the second drive unit while the first drive unit is operating.