JP2822109B2 - Variable width horizontal roll for hot rolling of H-section steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a horizontal roll having a variable width structure used for hot rolling an H-section steel.

[0002]

2. Description of the Related Art FIG. 4 shows hot rolling of an H-section steel. Reference numerals 10 and 10 denote horizontal rolls which are vertically opposed to each other with the web a of the rolled material w interposed therebetween.
Vertical rolls 20, 20 are arranged to lower the flange b of the roll. Each of the horizontal rolls 10, 10 is a rolled material w.
As shown in the figure, the roll a is divided into two right and left divided rolls 10 1 and 10 1 so that rolling control with respect to a change in the width dimension of the web a can be performed. It has a variable width structure that is close to or separated from each other while maintaining a symmetrical positional relationship. Conventionally, as the horizontal roll 10, a Nickel Glen cast iron roll (C:
3.1-3.5%, Si: 0.5-1.5%, Mn:
0.2-1%, Ni: 3.5-4.5%, Cr: 1-2
%, Mo: 0.2 to 0.7%, Fe: Bal) or an adamite cast iron roll (C: 1.7 to 2.2%, Si:
0.5-0.9%, Mn: 0.7-1.1%, Ni:
1.5-2%, Cr: 0.8-1.2%, Mo: 0.6
１．０1.0%, Fe: Bal) and the like. Nickel Glen cast iron roll has high hardness (Hs: about 75),
The adamite cast iron roll has excellent toughness (Shearpy impact value (no notch): about 1.3 kg)
fm / cm ² ).

[0003]

Each of the roll segments 10, 1 and 10 of the horizontal roll 10 has an outer end face on which the rolling load of the flange b of the rolled material w is parallel to the roll axis. Acts to produce shear and bending stresses. Conventionally, adamite cast iron rolls and nickel-glen cast iron rolls that have been used as horizontal rolls do not have sufficient toughness to withstand the above-mentioned load applied to the end faces, and breakage occurs when the roll wall thickness is reduced. There is a problem that it easily occurs. Moreover, since the adamite cast iron roll is relatively soft (Hs: about 60), under the use conditions in which the sliding contact friction of the flange b of the rolled material w is strongly applied to the body end face,
Nickel-glen cast iron rolls have the disadvantages that wear reduction of the end face is easy to progress and seizure easily occurs due to friction. On the other hand, nickel rolls have excellent wear resistance and seizure resistance. Value (no notch): about 0.27
kgf ・ m / cm ² )
Alternatively, in the case where cooling failure occurs, a fine crack is formed on the roll body, particularly on the corner portion thereof (a circumferential ridge pressed at the corner where the web a and the flange b of the rolled material w intersect). There is a disadvantage that chipping easily occurs.

[0004] The roll segment 10 · 1, 1 of the horizontal roll 10
If a breakage occurs in 0.1 or 0.1, the rolling operation must be interrupted, and even if the breakage does not occur, smooth running of the rolling operation will occur if thinning of the side walls or chipping of the corners occurs. And impairs the quality of the rolled product obtained. The present invention provides an improved horizontal roll for solving the above-mentioned problems relating to the variable width horizontal roll used for hot rolling of an H-section steel.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a variable-width horizontal roll used for hot rolling of an H-section steel, comprising left and right roll segments separated from each other by an axial shift drive. Each of the roll body portions of the right and left roll segments is a hollow cylindrical body 1 made of a tough material.
2. A cylindrical member 13 or a donut-shaped plate member 13 'made of a hard and wear-resistant material forming a roll end surface serving as a receiving surface of a rolled material flange, and a cylindrical member 14 formed of a tough material forming a roll peripheral surface And has a composite laminated structure in which the superposed surfaces of the members are joined by solid-phase bonding.

[0006]

The variable width horizontal roll according to the present invention uses a hollow cylindrical body made of a tough material as a base material of the roll body, so that it is capable of withstanding a load in the roll axis direction acting on each roll segment at the time of die steel rolling. Having a roll end face made of hard abrasion-resistant material that has breakage resistance, so that it has abrasion resistance to the pressure sliding contact of the rolled material flange and that the roll peripheral surface is formed of a ductile material. It has good corner chipping resistance.

Hereinafter, a body structure of a horizontal roll according to the present invention will be described with reference to the drawings showing an embodiment. In FIG. 1, reference numeral 12 denotes a substrate made of a tough material (11 is a shaft hole), and 13 denotes hard wear resistance for imparting wear resistance to a roll end surface on which a flange b of a rolled material w presses and slides. The cylindrical member 14 made of a material is a cylindrical member made of a ductile material for imparting corner-break resistance to the peripheral surface of the roll.
Each of the roll segments 10 1, 10 1 has a concentric laminated structure of a base material 12, a wear-resistant member 13, and a tough member 14, and each member is made of a hot isostatic press (HIP). 2) The superposed surfaces are firmly bonded to each other by the solid-phase bonding in the treatment to form a composite having the necessary rigidity for the roll.

The tough material, which is the base material 12 for imparting breakage resistance to the roll body, is, for example, a Cr-Mo alloy steel (JIS G4105 or the like) or ductile cast iron (C: 3.1 to 3). 0.7%, Si: 1.2 to 2.3%, M
n: 0.2 to 0.8%, Ni: 1.5% or less, Cr:
0.5% or less, Mo: 0.1 to 0.4%, Fe: Ba
l) and the like are preferably used. The Cr-Mo alloy steel, which is an alloy steel for machine structure, has a tensile strength of about 70 kgf / mm.
² and an elongation of about 10% or more. The ductile cast iron has a tensile strength of about 50 kgf / mm ² and an elongation of about 1.3.
% Or more, and the conventional high-hardness adamite cast iron as a horizontal roll material (tensile strength: about 66 kgf / mm ² , elongation: about 0.
9%) or Nickel Glen cast iron (tensile strength: about 45 kgf)
/ Mm ² , elongation: about 0.3%). The horizontal roll of the present invention has better breakage resistance than conventional horizontal rolls due to the toughness of the substrate.

Hard wear-resistant member 13 laminated on substrate 12
Is a nickel-grain cast iron, for example, and a ductile member 14 which is layered on the outer periphery to form a peripheral surface is, for example, adamite cast iron. The layer thickness of the ductile member 14 forming the peripheral surface layer is, for example, 5 to 20 mm. Needless to say, the wear-resistant member 13 has a layer thickness (radial thickness) sufficient to be a receiving surface for the entire projection width of the flange b of the rolled material w. The breakage due to the rolling load of the flange b of the rolled material w acting on the roll body in the axial direction of the roll is determined by the fact that the maximum part of the combined shear and bending stress generated by the cantilever beam is the material of that part of the roll. Occurs when the strength is greater than the strength. The radially thick portion serving as the receiving surface of the flange b of the rolled material w has almost no effect of the combined stress of shearing and bending. Therefore, as shown in FIG. Even in the case of a laminated structure in which the thick portion is formed of a material having relatively low toughness, such as nickel-glen cast iron, over the entirety in the axial direction, there is no possibility that the thick portion will be broken. Of course, since the lamination interface between the member 13 and the base material 12 is firmly bonded by the solid-phase bonding in the HIP process, there is no occurrence of damage such as peeling at the lamination interface.

Abrasion-resistant member 1 in horizontal roll of the present invention
Numeral 3 is a member for protecting the end face of the roll body from abrasion caused by the sliding contact of the flange b of the rolled material with the flange b, so that the axial direction between the base material 12 and the tough member 14 is not necessarily required as shown in FIG. It is not necessary to intervene over the entire length, and as a matter of course, as shown in FIG. The wear-resistant member 13 'is a donut-shaped plate member that makes a round around the body end face, and has a plate thickness of, for example, 10 to 30 mm.
It is.

The outer shape of the roll body of the present invention is not limited to those shown in the above-mentioned drawings, and corresponds to a rolling schedule such as rough rolling, intermediate rolling, finish rolling in a rolling process of a wide flange type steel material, or Depending on the product shape, the shape may be designed to have a tapered side surface as shown in FIG. 3, for example.

The roll body of the horizontal roll of the present invention comprises a base material 12 and members (13, 13 ', 14) which are composited therewith.
And vacuum sealing (for example, 1 × 10 ⁻¹ Torr) using a steel capsule or the like as a canning material, and then performing a HIP process to solid-phase join the superposed surfaces of the members. The HIP processing conditions are as follows:
By holding at 1500 kgf / cm ² , at a temperature of about 800 to 1200 ° C., and holding for an appropriate period of time (about 1 to 4 hr), solid joining of the members can be successfully achieved to form a firmly bonded laminated composite. it can.

After the HIP processing is completed and the canning material is removed by machining, a heat treatment for refining is performed. The heat pattern of the heat treatment is appropriately set according to the combination of the material types of each member of the composite laminate. For example, the substrate 12
Is Cr-Mo alloy steel or ductile cast iron, member 1
In the case of a combination of grades in which 3 is nickel-glen cast iron and the member 14 is adamite cast iron, it is preferable to perform heat treatment in a temperature pattern of performing tempering at 500 to 600 ° C. after cooling from 900 to 1000 ° C.

[0014]

The horizontal roll of the present invention has excellent resistance to cracking, and has abrasion resistance of the end face and chipping resistance of the peripheral surface corner, so that it is stable in hot rolling of H-shaped steel materials. It can contribute to the improvement and stabilization of the quality of rolled products, such as improvement of service life, reduction of roll maintenance, and efficiency of rolling operation.

[Brief description of the drawings]

FIG. 1 is a partial axial sectional view showing an example of a laminated composite structure of a horizontal roll according to the present invention.

FIG. 2 is a partial sectional view in the axial direction showing an example of a laminated composite structure of a horizontal roll according to the present invention.

FIG. 3 is an axial sectional view showing another example of the outer shape of the body of the horizontal roll of the present invention.

FIG. 4 is a schematic front view showing hot rolling of an H-section steel by a variable width horizontal roll.

[Explanation of symbols]

10: horizontal roll, 10: 1: horizontal roll split, 12:
Substrate, 13 (13 ') 14: laminated member, 20: vertical roll, w: rolled material, a: web, b: flange.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yutaka Nakai 64 Nishimujimajima-cho, Amagasaki City, Hyogo Prefecture Inside Kubota Amagasaki Plant Co., Ltd. 72) Inventor Hironori Miura 313-5 Fukushima, Kurashiki City, Okayama Prefecture (56) References JP-A-54-99759 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B21B 27 / 00-27/05 B23K 20/00 B22F 3 / 14,5 / 00

Claims (2)

(57) [Claims] 1. A horizontal roll composed of left and right roll segments having a variable width structure which is moved close to or separated from each other by an axial shift drive, wherein each roll body of the left and right roll segments is made of a tough material. A hollow cylindrical body made of a hard abrasion-resistant material whose end face is a receiving surface of a rolled material flange, which is fitted to the peripheral surface of the substrate, and a peripheral surface of the cylindrical member The H-shaped steel is characterized in that it is a fitted cylindrical member made of a tough material that forms a roll peripheral surface, and a superposed surface of each member is a composite laminate joined by solid-phase bonding. Variable width horizontal roll for hot rolling. 2. A horizontal roll composed of left and right roll segments having a variable width structure which is close to or separated from each other by an axial shift drive, wherein each roll body of the left and right roll segments is made of a tough material. A hollow cylindrical body, a donut-shaped plate member made of a hard wear-resistant material, which is a flange receiving surface member applied to an end face of the base material facing a rolled material flange, and the base material A cylindrical member made of a tough material forming a roll peripheral surface, which is fitted to the peripheral surface of the roll, and a superposed surface of each member is a composite laminate bonded by solid-phase bonding. Variable width horizontal roll for hot rolling of H-section steel.