| 摘要 |
The tube (10) comprises a downstream part (14), and an upstream part (16) that is defined as a part of the tube lying between an upper transverse plane, which is tangent to an upper end of the tube and a lower transverse plane located at a threshold distance from the upper transverse plane. The tube defines a runner (12) having a casting axis and an outlet diameter. The threshold distance has a dimension, which is five times greater than the outlet diameter. The upstream part is flared so that its upper end has a general convex form in an axial direction. The tube (10) comprises a downstream part (14), and an upstream part (16) that is defined as a part of the tube lying between an upper transverse plane, which is tangent to an upper end of the tube and a lower transverse plane located at a threshold distance from the upper transverse plane. The tube defines a runner (12) having a casting axis and an outlet diameter. The threshold distance has a dimension, which is five times greater than the outlet diameter. The upstream part is flared so that its upper end has a general convex form in an axial direction and has a surface of intersection with the upper transverse plane of which a width in a radial direction is less than the half of the outlet diameter. The upstream part is included within: a first volume corresponding to a complementary part of a rotating tapered volume having casting axis, where a generator of the complementary part forms an alpha angle (alpha ) of 7[deg] with the casting axis; and a second volume, which is bounded by a rotating surface generated by an isosceles trapeze rotating around the casting axis. A small base (22) of the tapered volume corresponds to the surface of intersection of the transverse plane with the runner. A small base of the trapeze is present in the upper transverse plane. A center of the upper end of the tube and a width for dimension are equal to half of the outlet diameter. A large base of the trapeze is located in the lower transverse plane, and the two non-parallel sides of the trapeze form assembly at a beta angle (beta ) of 20[deg] . Independent claims are included for: (1) an assembly including a tube and a metal frame for receiving an upper end of a tube; and (2) a metal frame. |
