| 摘要 |
A method and apparatus for making a true butt-welded cylindrical printing screen for a rotary screen printing press, wherein the screen material is rigidized woven metal screen. The method of making the cylindrical screen of the invention includes the steps of cutting a rectangular piece of rigidized woven metal screen material of a size to form a screen of a predetermined size, forming the piece into a cylindrical shape so that two edges are abutting each other to form a butt seam such that sufficient metal will be present to provide a proper weld, mounting the screen on a support bar so that the abutting edges line up with a stationary electrode carried by the support bar, where the electrode includes a tip of narrow width in the range of 0.010 to 0.040 inches, and running an upper electrode along the other side of the butt seam to resistance weld the two edges of the screen material together and form a butt weld. The apparatus includes a support bar for holding the stationary electrode, means for mounting and holding the screen material edges together on the support bar in alignment with a thin elongated electrode carried by the support bar, and means for driving an upper electrode along the butt seam to effect the welding of the edges together.
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