GB1067905A - Improvements in and relating to a machine for welding finned tubes - Google Patents

Abstract

1,067,905. Welding by fusion. WALTHER & CIE A.G. June 2, 1965 [June 5, 1964], No. 23498/65. Heading B3R. In a machine for welding finned tubes to form tube sheets, the tubes are guided by pairs of profiled guide rollers, the distance between the rollers of each pair is adjustable and at least one roller of each pair is driven. The machine comprises three sets of guide rollers, each set comprising two pairs of rollers. The lower rollers 9, 10, 11 of each set are mounted on bearings in slideways 6, 7, 8 and are vertically adjustable by a hand wheel 13. The upper rollers 23, 24, 25 of each set are mounted in slideways 14, 15, 16 and are moved vertically by hydraulic rams 20, 21, 22 whose action is modified by air cushions to provide a resilient loading. A fully adjustable submerged arc welding head 30 is mounted from the machine frame by linkage 34 having vertical pivots and is aligned with the seam by a seam engaging guide wheel 32. A used flux extractor 39 follows the head 30. A resiliently mounted backing wheel 40 of copper or silver-plated is located under the head 30 and dips into a cooling bath 41. Motor driven wire brushes may be provided to clean the fins prior to welding. A carbon dioxide shielded welding head 42 leading the welding head 30 and acting on the underside of the seam is guided by a seam engaging guide wheel 43. The earth return includes weighted braided wire loops 45 engaging the spindles of the lower rollers 9, 11. Spacers may be inserted between the pairs of rollers to cater for different tube spacings. In a modification, the machine has welding heads mounted side-by-side to join three finned tubes by two welds.