Hitachi, Ltd.

Shinichi Kaga

Yasutsugu Yoshimura

Yoshio Takakura

Takao Sakanaka

Toshiyuki Kajiwara

Kenjiro Narita

Ken-ichi Yasuda

Tokuji Sugiyama

Takashi Kamoshita

Mitsuo Nihei

Yukio Hirama

Kouji Satou

Takehiko Saito

Toshiyasu Shinmura

Tadashi Nishino

Kenichi Yasuda

Shinichi Yasunari

Yasutsuga Yoshimura

Yukio Nakajima

Ken-ichi Yoshimoto

A rolling mill, a gap-removing apparatus for roll bearing boxes, a rolling method, a modifying method for a rolling mill, and hot finish tandem rolling equipment are provided with roll bearing boxes for rotatably supporting work rolls in a housing, a first pushing device for applying a vertical balancing force or bender force to the work rolls through the roll bearing boxes, and a second pushing device for applying a pushing force in a direction orthogonal to the work roll axis in a horizontal plane to the roll bearing boxes. The first pushing device and the second pushing device are disposed to be offset from each other in the work roll axis direction. In certain arrangements, the second pushing device is disposed between a plurality of the first pushing devices in the work roll axis direction. Gaps at the roll bearing boxes in the rolling mill can be removed without enlarging the equipment in size.

Rolling mill, looseness eliminating device of roll bearing housing, rolling method, method of modifying rolling mill, and hot finishing tandem rolling equipment

There are disclosed a rolling mill capable of keeping a uniform plate of thickness distribution and manufacturing a good-quality plate, and a rolling method. The rolling mill comprises working rolls movable in roll axis directions, profile-measuring means for measuring the profile of each of the working rolls, profile-estimating means for estimating the profile thereof, and a grinder for grinding each of the working rolls. The rolling mill also comprises instructing means for sending a command of grinding to the grinder at a time when the measured profile value or the estimated profile value regarding each of the working rolls reaches a given value.

Rolling mill and rolling method

There are disclosed a rolling mill capable of keeping a uniform plate thickness distribution and manufacturing a good-quality plate, and a rolling method. The rolling mill comprises working rolls movable in roll axis directions, profile-measuring means for measuring the profile of each of the working rolls, profile-estimating means for estimating the profile thereof, and a grinder for grinding each of the working rolls. The rolling mill also comprises instructing means for sending a command of grinding to the grinder at a time when the measured profile value or the estimated profile value regarding each of the working rolls reaches a given value.

A work roll crossing type rolling mill has back-up rolls arranged in such a manner that their axes are not inclined in a horizontal plane. Work rolls are constructed in such a manner that their axes can be inclined in a horizontal plane relative to the backup rolls such that the axes of the work rolls cross the axes of the back-up rolls and such that the axes of the work rolls cross each other. A lubricant supply device is provided for supplying a lubricant between each work roll and each back-up roll combination to greatly reduce the thrust exerted to the work rolls, whereby the rolling mill is given an excellent ability of controlling the crown of the material to be rolled.

Rolling mill, hot rolling system, rolling method and rolling mill

A work roll cross type rolling mill comprises a pair of work rolls and a pair of back-up rolls for backing up the work rolls. The back-up rolls are so arranged that their axes can be inclined within horizontal planes only to three or four specific angular positions. The work rolls are allowed to be inclined within horizontal planes with respect to the back-up rolls such that the axes of the work rolls cross the axes of the associated back-up rolls and cross each other. The nip between each the work roll and the associated back-up roll is lubricated so as to reduce axial thrust generated therebetween due to the crossing of the rolls. The cross angle between the work rolls is set and controlled during rolling operation only when the roll peripheral speed or the rolling speed is 50 m/min or higher. Advantages of work roll cross type rolling mill are fully extended to realize stable rolling without trouble so as to ensure high quality of the rolled product while achieving higher rate of operation of the mill with facilitated operation.

Rolling mill and method of using the same

In a tandem mill system, at least one first type rolling mill is arranged in the upstream side and at least one second type rolling mill is arranged in the downstream side. The first type rolling mill is of the so-called work roll crossing mill in which a pair of work rolls are inclined with respect to a pair of back-up rolls supporting the work rolls and simultaneously crossed each other in a horizontal plane to control transverse thickness distribution of a strip. The second type rolling mill is of the so-called HC mill which controls the strip crown and shape by a combination of axial movement of intermediate rolls and work roll bending. Such an arrangement makes it possible to increase a capability of controlling the strip crown and shape, particularly, a capability of correcting the quarter buckle, and eliminate a fear of causing scratches on the strip and roll surfaces, with the result of improved production efficiency. Plural lines of lubricant supply device are also provided to stop supply of a lubricant immediately before biting of the strip into the work roll crossing mill and start the supply again after the biting. A system of lubricating the work roll crossing mill is thereby improved.

Tandem mill system and work roll crossing mill

In a system and method for manufacturing thin plate by hot-working, a splicing machine for continuously splicing the front edge of a following plate and the rear edge of a precedent plate is provided in the process precedent to a set of rolling mill stands having non-driven small diameter working rollers. By continuously splicing the plates, most portions of the rolled plates can be rolled under a steady state rolling condition, that is, an after-engaged rolling condition, and the thickness reducing amount of the plates in most portions of the rolled material is substantially increased, which substantially improves the rolling efficiency. Thereby, the diameter of the working rollers can be decreased smaller than the diameter of working roller used in a conventional rolling mill, rolling mill strands can be made small, and it can be realized to attain a small-scale system for manufacturing thin plate by hot working.

System and method for manufacturing thin plate by hot working

A lubricant is supplied from headers of lubricant supply units onto surfaces of back-up rolls at locations spaced from contact positions between a pair of work rolls and a pair of back-up rolls. The headers each include a lubricant spray nozzle for spraying the lubricant under a pressure not lower than 3 kg/cm.sup.2, a header cover for confining the lubricant sprayed from the lubricant spray nozzle, an oil return line for returning the surplus lubricant, and seal members made of flexible material such as rubber. The work rolls are provided with water wiping plates, and the back-up rolls are also provided with water wiping plates. In a work rolls crossing type mill thus arranged, water films of cooling water deposited on the roll surfaces are removed to prevent the cooling water from mixing into the lubricant. Even if the water films are not totally removed, it is possible to surely plate out the lubricant for reliably lubricating between the work rolls and the back-up rolls. Raw lubricant oil of the lubricant meets the following requirements; (a) the coefficient of friction between said work rolls and said back-up rolls is in the range of 0.04 to 0.1, (b) the viscosity is not larger than 80 Cst. at 40.degree. C., (c) mineral oil and synthetic ester not less than 5% are contained as base oil, (d) a fatty acid in the range of 0.03 to 0.5% is contained as an oiliness enhancer, (e) an extreme pressure additive not less than 0.1% is contained, and preferably, (f) a surface active agent not larger than 0.5% is contained as emulsifier.

Growing community of inventors

Hitachi, Japan

Shinichi Kaga