Finishing Monoblock with Optimised Transmission Ratio for a Billet Rolling Plant
A finishing monoblock with optimised transmission ratio for a billet rolling plant comprises a plurality of rolling stands (G 1 -Gn) arranged in sequence suitable for forming a rolling line and actuated by a pair of mechanical transmissions ( 11, 12 ) in which bevel gear pairs are foreseen for the variation of ratio in the stands of the rotation speed of rolling cylinders ( 18 ). According to the invention, such a variation of the ratio in the stands is carried out through the combination of a first type (A, B) of bevel gear pairs with a second type of bevel gear pairs (C, D) and there is a set of four of cylindrical gears suitable for making four stands (C, D) with the same transmission bevel gear pair.
1 . Finishing monoblock with optimised transmission ratio for a billet rolling plant of the type comprising a plurality of rolling stands (G 1 -Gn) arranged in sequence suitable for forming a rolling line and actuated by a pair of mechanical transmissions ( 11 , 12 ) in which bevel gear pairs are foreseen for the variation of ratio in the stands of the rotation speed of rolling cylinders ( 18 ), characterised in that such a variation of the ratio in the stands is carried out through the combination of a first type (A, B) of bevel gear pairs with a second type of bevel gear pairs (C, D) and in that there is a set of four of cylindrical gears suitable for making four stands (C, D) with the same transmission bevel gear pair.
2 . Finishing monoblock with optimised transmission ratio according to claim 1 , characterised in that the total transmission ratio for a monoblock of ten stands (G 1 -G 10 ) is equal to 5.6907497 from which one takes a ratio given by the difference between the ratios of the sets of four and equal to 1.5454545 so that a ratio of just 3.6822498 remains to be distributed.
3 . Finishing monoblock with optimised transmission ratio according to claim 1 , characterised in that the differentiation of the set of four provides for a group of two stands, having optimised the intermediate stands with a ratio very close to 1:1, preferably close to 1.244898 and close to 0.8032786.
4 . Finishing monoblock according to claim 1 , characterised in that the total transmission ratio for a monoblock of eight stands (G 1 -G 8 ) is close to 682249 from which a ratio given by the sets of four close to 1.5454545 is taken, with it remaining for the bevel gear pairs to distribute just a ratio close to 2.965602.
5 . Finishing monoblock according to claim 4 , characterised in that the bevel gear pairs remain identical for the second and third group of two stands obtaining the use of just two types of bevel gear pairs for all eight stands, instead of the four types of bevel gear pairs of the old solution.
6 . Finishing monoblock according to claim 1 , characterised in that it requires just the transmission of a single cage with two sets of bearings with bevel gear pairs, of two types, as stock.