Surface cutting apparatus for hotrolled steel products

Abstract: The present invention relates to a surface cutting apparatus for hot-rolled steel products for cutting the top and bottom surfaces of a hot-rolled steel product continuously or intermittently by passing said steel product between a pair of rotary drums (82a,82b) rotating in the direction reverse to each other, said apparatus having a movable sheet passing guide (100) for holding the hot-rolled steel product during the period of time when the steel product advances from the input side to the output side of the rotary drum pair.

Description: TECHNICAL FIELD The present invention relates to a surface cutting apparatus according to the preamble of claim 1. Such apparatus is known from EP-0 430 070. It is an object of the present invention to provide an apparatus which can advance a preceding sheet from an input-side to an output-side without dropping during loading of the apparatus. For solving the above object, the present invention provides a surface cutting apparatus as defined in claim 1. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view showing a state in which the leading edge of steel product hangs down; Fig. 2 is a view showing a configuration of the side of the cutting apparatus in accordance with the present invention; Fig. 3 is a view taken along the line III-III of Fig. 2; BEST MODE FOR CARRYING OUT THE INVENTION The following is a description of a case where surface cutting is achieved while a sheet is conveyed stably by preventing deformation of hot sheet, especially downward deformation of leading edge. Fig. 1 is a side view of a sheet surface cutting apparatus. In the apparatus thus configured the heights of the rotary drums 82a and 82b are adjusted, the leading edge of preceding sheet S 1 is passed through the opposing section of a pair of rotary drums 82a and 82b, and the rotary drums 82a and 82b are moved close to each other while being rotated at a high speed just before the joint portion with the following sheet S 2 reaches the opposing section of the pair of rotary drums 82a and 82b, by which the projections at the joint portion L of sheet is cut. At this time, the preceding sheet S 1 passing between the pair of rotary drums 82a and 82b is at a temperature of about 800 to 900°C, so that the strength thereof is decreased. Therefore, there is a possibility that the leading edge of preceding sheet S 1 passing through an input-side apron 83 hangs down, as indicated by the two-dot chain line in the figure. Since a fixing apron cannot be installed between the pair of rotary drums 82a and 82b, if the leading edge of following sheet S 2 hangs down, it comes in contact with an output-side apron 84 or the cutting edge of lower rotary drum, so that there is fear of damage to cutting edge of rotary drum or incapability of passing of sheet. According to the present invention, in the apparatus for cutting the top and bottom surfaces continuously or intermittently by passing a hot sheet between the pair of rotary drums rotating in the direction reverse to each other, a movable sheet passing guide for holding the hot sheet for the period during which the leading edge of preceding sheet advances from the input side to the output side of the rotary drum. Until the leading edge of preceding sheet passes between the rotary drums and reaches the output-side apron, the sheet passing guide is inserted between the input-side apron and the output-side apron to guide the leading edge of preceding sheet by using the sheet passing guide. Therefore, the deformation of sheet, especially of the leading edge thereof, can be prevented, and the incapability of passing of sheet does not occur, so that the joint portion of sheet can be cut to a predetermined depth by setting a predetermined gap between the upper and lower rotary drums before the joint portion between the preceding and following sheets reaches the rotary drum. Figs. 2 and 3 show a configuration of cutting apparatus in accordance with the present invention. A pair of rotary drums 85a and 85b of the cutting apparatus is formed with cutting edges 86a and 86b with a width larger than the maximum sheet width on the outer peripheral surface. A roll chock 89 is supported by a housing 87 of the cutting apparatus via a screw down cylinder 88 so as to movable vertically, and the upper rotary drum 85a is rotatably supported by the roll chocks 89. Also, a roll chock 91 is supported by the housing 87 via a height adjusting cylinder 90 so as to be movable vertically, and the lower rotary drum 85b is rotatably supported by the roll chocks 91. The roll chocks 89 and 91 are supported by balance cylinders 92 respectively, so that the heights of the rotary drums 85a and 85b are adjusted. On the sheet pass line, an apron 93, a table roller 94, an input-side apron 95, an output-side apron 96, a table roller 94, and apron 93 are installed from the upstream side. The preceding sheet S 1 is carried from the input-side apron 95 to between the pair of rotary drums 85a and 85b by being guided by the input-side apron 93 and the table roller 94, and carried out by passing through the output-side apron 96 by being guided by the output-side apron 93 and the table roller 94. As shown in Figs. 2 and 3, at the lower part of the housing 87 is provided a center shaft 97 extending in parallel with the rotating shafts for the rotary drums 85a and 85b, and the base end of an arm 98 is rotatably supported by the center shaft 97. A plurality of rows of arms 98 extending toward the output-side direction are arranged in the axial direction of the rotary drum 85a, 85b, and a connection plate 99 is mounted at the tip end of the arm 98. The connection plate 99 is provided with arcuate sheet passing guides 100. A plurality of rows of sheet passing guides 100 are arranged in the axial direction of the rotary drum 85a, 85b. By turning the arms 98 around the center shaft 97, the sheet passing guides 100 are attached from or detached to the output side to or from between the pair of rotary drums 85a and 85b between the input-side apron 95 and the output-side apron 96, that is, between the lower rotary drum 85b and the sheet passing plane. A connection plate 101 is installed at the intermediate part of the arm 98, and an operating rod 103 of a turning cylinder 102 is pivotally mounted to the connection plate 101. Thus, by extending/contracting the operating rod 103 by the drive of the turning cylinder, the arms 98 are turned around the center shaft 97, so that the sheet passing guides 100 are attached to or detached from between the lower rotary drum 85b and the sheet passing plane. Before a preceding sheet S 1 and a following sheet S 2 are joined, the upper and lower rotary drums 85a and 85b are apart from each other, and after the preceding sheet Si and the following sheet S 2 are joined, the operating rod 48 is extended by the drive of the turning cylinder 102 before the leading edge of preceding sheet S 1 reaches the cutting apparatus. By the extension of the operating rod 103, the arms 98 are turned around the center shaft 97, by which the sheet passing guides 100 are inserted between the lower rotary drum 85b and the sheet passing plane from the output direction (the state indicated by the two-dot chain line in Fig. 2). In this state, the leading edge of preceding sheet S 1 advances from the input-side apron 95 to the output-side apron 96 by being guided by the sheet passing guides 100 without dropping. When the leading edge of preceding sheet S 1 reaches the output-side table roller 94 and the apron 93, the operating rod 103 is contracted by the drive of the turning cylinder 102 to return the plate passing guides 100 to the original positions (the state indicated by the solid line in Fig. 2). After the plate passing guides 100 are returned to the original positions, the heights of rotary drums are adjusted by the adjustments of the screw down cylinder 104 and the height adjusting cylinder 90. Just before the joint portion L of the preceding sheet S 1 and the following sheet S 2 reaches between the rotary drums 85a and 85b, the upper and lower rotary drums are rotated at a high speed in the direction reverse to the sheet advance direction. In cutting, the upper and lower rotary drums 85a and 85b are moved close to each other by the screw down cylinder 104 and the height adjusting cylinder 90, respectively, to cut the top and bottom surfaces at the same time while removing the projections M at the joint portion L. In this example, the rotary drums 85a and 85b are rotated in the direction reverse to the sheet advance direction. However, they may be rotated in the sheet advance direction. Also, the sheet passing guides 100 are formed into an arcuate shape, and the sheet passing guides 100 are attached or detached by turning the arms 98 in this example. However, plate-shaped sheet passing guides may be attached to or detached from between the rotary drums by being slid. Thus, in the present invention, movable sheet passing guides 100 are provided between the rotary drum and the sheet passing plane in the cutting apparatus, and the sheet passing guides 100 are inserted between the upper and lower rotary drums to guide the leading edge of preceding sheet S 1 when the leading edge of preceding sheet S 1 passes between the rotary drums. Therefore, the leading edge of preceding sheet does not come in contact with the output-side apron by high-temperature deformation etc. INDUSTRIAL APPLICABILITY According to the present invention, the following effects can be expected. In the case where continuous rolling is performed by installing the joining device for joining the tail edge of preceding hot-rolled steel product to the leading edge of following hot-rolled steel product between the rough rolling mill group and the finish rolling mill group, the rotary drums having a width larger than the maximum sheet width of rolled product are arranged above and below the steel product between the joining device and the finish rolling mill group, and the sheet passing guides are installed detachably between the lower rotary drum and the sheet passing plane for the steel product, so that the sheet passing guides are inserted between the upper and lower rotary drums when the preceding steel product passes between the rotary drums, and the leading edge of preceding steel product is passed to the output side by being guided by the sheet passing guides. After the leading edge thereof reaches the output side, the sheet passing guides are removed from between the upper and lower rotary drums, and before the joint portion between the preceding steel product and following steel product reaches the rotary drums, the upper and lower rotary drums are rotated and moved close to each other, by which the joint portion can be cut to a predetermined depth. As a result, the leading edge of preceding steel product can be prevented from hanging down or contacting with the apron etc., and the incapability of sheet passing can be eliminated completely.

Claims: A surface cutting apparatus for hot-rolled steel products for cutting the top and bottom surfaces of a hot-rolled steel product continuously or intermittently by passing said steel product between a pair of rotary drums (85a, 85b) rotating in the direction reverse to each other, characterized in that said apparatus having a movable sheet passing guide (100) for holding the hot-rolled steel product during the period of time when the steel product advances from the input side to the output side of the rotary drum pair in a state where upper and lower rotary drums (85a, 85b) are apart from each other, wherein said sheet passing guide (100) is inserted between the lower rotary drum (85b) and the sheet passing plane.

Inventors: AMAGASA TOSHIAKI, HAYASHI KANJI, HIRABAYASHI TAKESHI, ICHIKIZAKI TETSUO, ISOYAMA SHIGERU, KATSURA SHIGEFUMI, KURODA MOTOFUMI, NAKAGAWA TADASHI, NIKAIDO HIDEYUKI, SHIMIZU MASUTO, TAKAGI MITSUHIRO, TASHIRO SHOZO, YUKI ATSUSHI, AMAGASA, TOSHIAKI, HAYASHI, KANJI, HIRABAYASHI, TAKESHI, ICHIKIZAKI, TETSUO, ISOYAMA, SHIGERU, KATSURA, SHIGEFUMI, KURODA, MOTOFUMI, NAKAGAWA, TADASHI, NIKAIDO, HIDEYUKI, SHIMIZU, MASUTO, TAKAGI, MITSUHIRO, TASHIRO, SHOZO, YUKI, ATSUSHI, AMAGASA, Toshiaki, Kawasaki Steel Corporation, Hayashi, Kanji, Mitsubishi Jukogyo Kabushiki K., HIRABAYASHI, Takeshi, Kawasaki Steel Corporation, Ichikizaki, Tetsuo, Mitsubishi Jukogyo K. K., ISOYAMA, Shigeru, Kawasaki Steel Corporation, KATSURA, Shigefumi, Kawasaki Steel Corporation, Kuroda, Motofumi, Mitsubishi Jukogyo Kabushiki K., Nakagawa, Tadashi, Mitsubishi Jukogyo Kabushiki K., NIKAIDO, Hideyuki, Kawasaki Steel Corporation, SHIMIZU, Masuto, Kawasaki Steel Corporation, Takagi, Mitsuhiro, Mitsubishi Jukogyo Kabushiki K., Tashiro, Shozo, Mitsubishi Jukogyo Kabushiki K., YUKI, Atsushi, Kawasaki Steel Corporation
Applicants: JFE STEEL CORP, MITSUBISHI HEAVY IND LTD, JFE STEEL CORPORATION, MITSUBISHI JUKOGYO KABUSHIKI KAISHA
Application year: 1996
Main classification: B23C3
IPC codes: B23Q11, B21B15, B23C3