GB1385644A - Pipe bending machine - Google Patents

Abstract

1385644 Pipe bending die CRC-CROSE INTERNATIONAL Inc 13 Feb 1973 [22 March 1972] 7068/73 Heading B3E A bending die 10 of a pipe bending machine comprises a support member 20 including a first bearing surface 31, Fig. 4, providing main external support for the pipe 12 in the direction of the bend and a second bearing surface 32 for supporting externally the sides of the pipe against outward bulging during the bending with the respective bearing surfaces presenting conjunctively a continuous external support of preselected shape to the pipe, and a bending device 14, Fig. 1, for bending the pipe longitudinally around the die. The support member has a transversely concave and longitudinally convex inwardly facing surface. Bearing surface 31 comprises a plurality of strips 34 of hard material, e.g. brass, steel, and the second surface 32 comprises strips 34 with bands 35 of compressible material of low coefficient of friction, e.g. polurethane solid elastomer, bonded thereto. The region between planes (29), (30), (Fig. 3, not shown), which does not support the pipe during bending is constructed as bearing surface 32 to prevent damage to the pipe during bending. In an alternative embodiment, Fig. 7, a plurality of strips are secured longitudinally along surface 24 of member 20, each strip comprising an underlying ribbon 44 of hard material, e.g. brass, steel, with bands 48 of compressible material bonded thereto to form the second bearing surface 32. Secured to ribbons 44 throughout surface 31 are metallic ribbons 50 to give a combined thickness of ribbons 44, 50 slightly less than ribbon 44 and band 48. Compressible inserts 52 are secured in cavities 54 of ribbons 50 to form surface 31.