摘要:
Provided is a method for producing a double-wall tube with braided wires at its interface in which the braided wires are interposed between an outer-wall and inner-wall blank tubes and then a drawing process is applied so as for the braided wires to be brought into close contact with the inner surface of the outer-wall tube and the outer surface of the inner-wall tube, the method comprising: polishing the inner surface of the outer-wall blank tube and the outer surface of the inner-wall blank tube so that a surface roughness thereof satisfies Ra
摘要:
Provided is a method for producing a double-wall tube with braided wires at its interface in which the braided wires are interposed between an outer-wall and inner-wall blank tubes and then a drawing process is applied so as for the braided wires to be brought into close contact with the inner surface of the outer-wall tube and the outer surface of the inner-wall tube, the method comprising: polishing the inner surface of the outer-wall blank tube and the outer surface of the inner-wall blank tube so that a surface roughness thereof satisfies Ra
摘要:
A plug 1 includes a first columnar portion 20, a tapered portion 30, and a second columnar portion 40. The first columnar portion 20 has an outside diameter D1. The second columnar portion 40 has an outside diameter D2 which is larger than the outside diameter D1. The tapered portion 30 is formed between the first columnar portion 20 and the second columnar portion 40. The tapered portion 30 has a tapered surface 31 provided with an outside diameter which is gradually increased from the first columnar portion 20 to the second columnar portion 40, and an axial direction length L. The outside diameters D1 and D2, and the axial direction length L meet the following expressions (1) to (4): 0.25≦ρ≦2.00 (1), 0.06≦L/D2≦0.8 (2), L/D2≦0.3×ρ+0.575 (3), and L/D2≧0.1×ρ (4) where ρ=(D2−D1)/D1×100. Therefore, the cold drawing plug according to the present invention can reduce the tensile residual stress on the outer surface of a metal pipe after the cold drawing.
摘要:
The present invention provides a mechanical pipe-end expander comprising a cone and a die having tapered wedge bodies whose outer radius is larger towards a flangeless end direction from a flange end, wherein a pipe-end zone is expanded by a wedge effect of the die, which results from a procedure that the cone and the die are inserted together into the pipe-end zone to be expanded, and that then only the cone is axially drawn outwards leaving the die within the pipe-end zone. A seamless steel pipe with an expanded pipe-end zone is manufactured by applying a mechanical pipe-end expander comprising a die having tapered wedge bodies whose outer radius is larger towards a flangeless end direction from a flange end. The resulting seamless steel pipe has satisfactory pipe-end dimensional accuracy, and exhibits characteristics with excellent field welding workability.
摘要:
A plug 1 includes a first columnar portion 20, a tapered portion 30, and a second columnar portion 40. The first columnar portion 20 has an outside diameter D1. The second columnar portion 40 has an outside diameter D2 which is larger than the outside diameter D1. The tapered portion 30 is formed between the first columnar portion 20 and the second columnar portion 40. The tapered portion 30 has a tapered surface 31 provided with an outside diameter which is gradually increased from the first columnar portion 20 to the second columnar portion 40, and an axial direction length L. The outside diameters D1 and D2, and the axial direction length L meet the following expressions (1) to (4): 0.25≦ρ≦2.00 (1), 0.06≦L/D2≦0.8 (2), L/D2≦0.3×ρ+0.575 (3), and L/D2≧0.1×ρ (4) where ρ=(D2−D1)/D1×100. Therefore, the cold drawing plug according to the present invention can reduce the tensile residual stress on the outer surface of a metal pipe after the cold drawing.
摘要:
An apparatus for sizing a pipe end comprising: a plug 3 for sizing the pipe end; a chuck 2 for clamping the pipe; and shifting means for shifting the position of the plug 3 and/the chuck 2, which are placed successively from the end of the pipe 2, and the plug 3 has a circular cross section, and is constituted by a taper portion 31 and a diameter equivalent portion 32 continuously formed from the tip of the plug in succession. The outer diameter of the taper portion 31 is gradually expanding from the tip toward the rear end while satisfying the following formulas (1) and (2). The chuck 2 is capable of changing clamping position of the pipe 1. This apparatus makes it possible to size the inner diameter of a pipe end with superior dimensional precision. 22≦LR/(D1×0.01/2)≦115 (1) R2≧R1 (2)
摘要:
The present invention provides a mechanical pipe-end expander comprising a cone and a die having tapered wedge bodies whose outer radius is larger towards a flangeless end direction from a flange end, wherein a pipe-end zone is expanded by a wedge effect of the die, which results from a procedure that the cone and the die are inserted together into the pipe-end zone to be expanded, and that then only the cone is axially drawn outwards leaving the die within the pipe-end zone. A seamless steel pipe with an expanded pipe-end zone is manufactured by applying a mechanical pipe-end expander comprising a die having tapered wedge bodies whose outer radius is larger towards a flangeless end direction from a flange end. The resulting seamless steel pipe has satisfactory pipe-end dimensional accuracy, and exhibits characteristics with excellent field welding workability.
摘要:
An apparatus for sizing a pipe end comprising: a plug 3 for sizing the pipe end; a chuck 2 for clamping the pipe; and shifting means for shifting the position of the plug 3 and/the chuck 2, which are placed successively from the end of the pipe 2, and the plug 3 has a circular cross section, and is constituted by a taper portion 31 and a diameter equivalent portion 32 continuously formed from the tip of the plug in succession. The outer diameter of the taper portion 31 is gradually expanding from the tip toward the rear end while satisfying the following formulas (1) and (2). The chuck 2 is capable of changing clamping position of the pipe 1. This apparatus makes it possible to size the inner diameter of a pipe end with superior dimensional precision 22≦LR/(D1×0.01/2)≦115 (1) R2≧R1 (2).
摘要:
A steel tube hot-finished by the Mannesmann tube-making method is subjected to a simple grinding process for the inner surface, and thereafter to a cold drawing, so that the depth d of the concave portion in the concavo-convex profile forming the inner surface of the steel tube, the surface roughness Ra and the width w of the entrance in the concave portion are specified, or similarly the depth d of the concave portion in the concavo-convex profile, the Vickers hardness Hv of the inner surface layer and the width w of the entrance in the concave portion are specified, hollow parts for a drive shaft, which have an excellent fatigue strength and which is optimal to reduce the weight of a car body, can be produced. Accordingly, the application of the manufacturing method according to the present invention allows drive shafts for automobiles to be efficiently produced in a reduced manufacturing cost, thereby providing a significant advantage in the industry.
摘要:
The through hole of a die has an inside surface including a bell portion, an approach portion, and a bearing portion from the entrance side formed in a continuous manner. The diameter of the approach portion is D1 on the entrance side of the approach portion and D2 on the exit side of the approach portion and gradually decreases from the entrance side to the exit side. The diameter satisfies Equation (1): 0.7≦D2/D1
摘要翻译:模具的通孔具有包括钟形部分,接近部分和从连续形成的入口侧的轴承部分的内表面。 接近部分的直径在接近部分的入口侧为D 1,而在接近部分的出口侧的直径为D 2,并从入口侧到出口侧逐渐减小。 直径满足公式(1):0.7 <= D 2 / D 1 <0.97。 直径D 3为D 2 /0.97的内表面的模半角不小于直径为D的内表面的靠近接近部分的出射侧的内表面的模具半角R 2 3,从直径为D 3的内表面到直径为D 2的内表面的轴向距离LR满足式(2):20 <= LR /((D 3 -D 2)/ 2) = 115。 轴承部分的通孔的直径固定为D 2,长度为LB,满足公式(3):0.3 <= LB / D 2 <= 10。