Abstract: A pad printing system for applying high quality multicolor images to curved objects is provided. The pad printing system includes a substantially flat release substrate having an ink receiving surface and a digital printer having a plurality of print heads. The print heads of the digital printer are arranged to discharge ink in a plurality of colors onto the ink receiving surface of the release media substrate. The print heads and release substrate are movable relative to each other such that the discharge of ink from the print heads prints a multicolor ink image on the ink receiving surface of the release substrate. The pad printing system further includes a deformable ink transfer pad which is movable into pressure contact with the release substrate for receiving a multicolor ink image therefrom and movable into pressure contact with a curved object to be printed for transferring a multicolor ink image from the transfer pad to the curved object.

Abstract: For increasing the resistance of steel pipes or tubes against acidic medium, by a combination of a heat treatment and the use of an alloyed steel, a compressure stress is built up on the side of the tubes or pipes facing the acidic medium, of up to 30% of the yield limit.