Nippon Kokan Kabushiki Kaisha

Yushiro Chemical Industry Co., Ltd.

Shinji Akita

Masayuki Hatanaka

Masachika Numano

Akira Uemura

Minoru Morita

Noboru Kanda

Megumu Tanaka

Tatsuharu Oda

Haruyuki Nakanishi

Kenzou Yokoyama

Ken-ichi Aoki

A lubricant for the production of seamless tubes comprising water-insoluble fine synthetic resin particles, fine gilsonite and graphite, in which about 30 parts by weight of water-insoluble fine synthetic resin particles, from about 15 to about 30 parts by weight of fine gilsonite particles and from about 40 to about 55 parts by weight of fine graphite powder are contained.

Lubricant for the production of seamless tubes

An inlet table for a restrained mandrel mill includes a plurality of roll units arranged in the pass line direction and the roll units are mechanically swung in synchronism with the forward and backward movements of a mandrel bar, thereby supporting the mandrel bar and/or a shell to be rolled on the pass line and preventing the roll units from striking against a restrained bar for moving the mandrel bar.

Restrained mandrel mill inlet table

A quenching method and apparatus for quenching a steel pipe heated throughout the length thereof to a given quenching temperature in which during cooling of the steel pipe, the pipe is rotated or the pipe is moved axially while rotating it thereby uniformly cooling the entire pipe. The apparatus is incorporated as an in-line equipment in a steel pipe production line whereby a steel pipe introduced from the preceding processing stage is quenched by the said quenching method and is then delivered automatically to the following processing stage thereby uniformly cooling the steel pipe in the lengthwise direction thereof and reducing the quenching time.

Quenching apparatus for steel pipes

Disclosed is a high-efficiency manufacturing installation in which seamless steel pipe rolling and finishing lines are matched in capacity with each other and are formed into a single continuous lines. The high-speed rolling line extends to a straightening machine via a cooling equipment for as-rolled pipes and a heat treating equipment for pipes to be heat-treated and is further connected to a single-line finishing line via a nondestructive inspection machine and a cutting machine. The finishing line comprises each plurality of different finishing machines arranged along a variable feed pitch transverse transfer line, the plural number being selected in correspondence to the capacity of the rolling line. The cooling equipment and the heat treating equipment are designed so that each of them requires the same transfer time and thus there is no danger of causing any blank in the feed pitch spacing during the change-over between the as-rolled pipes and the pipes to be heat-treated.

Seamless steel pipe manufacturing installation

In an apparatus for changing the rolling mill rolls and/or disk shoes of a steel pipe rolling mill, the top and bottom rolls vertically movably mounted in the housing are individually placed on a supporting bed positioned below the bottom rolling roll and moved in and out of the mill by way of rails laid in the lower part of the housing, and each of the disk shoes is mounted on a supporting arm which is movable vertically and rotatable thereby making it possible to change the disk shoes even during the operation.

Steel pipe rolling mill

In a three-roll Assel mill capable of automatically and rapidly changing the rolls, rails are arranged on an inner housing mounted within each of a fixed housing and a rotary housing to be rotatable along the inner wall thereof, and cradles having rolls mounted therein are placed on the rails, whereby during roll changing the housing proper is shifted and the inner housings are rotated in such a manner that the rails provided on the inner housings are successively aligned with rails laid externally and the rolls are moved in or out of the rolling mill.

A conditioning line for steel pipes in which steel pipes are transversely transferred to effect the end processing thread cutting, thread inspection, hydrostatic testing, etc., on the steel pipes. With a view to increasing the efficiency of the conditioning operations, a reprocessing line is arranged to run parallel to a main line such that the steel pipes rejected on the main line are automatically transferred to the reprocessing line where the rejected steel pipes are reprocessed and automatically transferred back to the main line.

Conditioning line for steel pipes

A roll changing apparatus for rolling mills which is adapted for use in the manufacture of seamless steel pipes. The apparatus comprises a pair of sliding bases each mounted on a base block and movable parallel to each other, a plurality of roll carriages each containing a set of rolls, and means for moving the roll carriages, wherein two or more of the roll carriages are placed on each of the sliding bases and at least one of the roll carriages on each sliding base is moved forward to form a roll mill. When the roll carriages are to be changed, the forwardly moved roll carriages are moved back onto the sliding bases and then the other roll carriages are moved forward, thus automatically accomplishing the roll carriage changing in a short period of time.

Roll changing apparatus for rolling mills

An apparatus for straightening the bend in steel pipes, round bars and the like (hereinafter simply referred to as steel pipes). The apparatus includes a first straightener comprising a combination of concave rolls and a second straightener comprising a combination of a concave roll and a convex roll and arranged at least at the entry side or the exit side of the first straightener and the top rolls or the bottom rolls of the first and second straighteners are adapted to be moved vertically, whereby when one or the other of the first and second straighteners presses a steel pipe, the pressure application of the other straightener is released so that the bend extending practically over the entire length of the steel pipe is straightened and the bend in the end portions of the steel pipe is straightened by the second straightener, thus straightening the steel pipe in a short period of time with a high degree of accuracy.

Straightening apparatus for steel pipes and the like

The present invention relates to an apparatus for changing the rolling-mill rolls and disk shoes of steel pipe rolling mills. The apparatus comprises mechanisms for raising and lowering a top and bottom cradle each holding a roll of a rolling mill and a carriage disposed below the bottom cradle and movable transversely, whereby the cradles are moved in and out of the rolling mill housing transversely by the carriage, and a plurality of holding devices each rotatable about a fixed shaft are selectively positioned opposite to a pair of chocks holding a pair of disk shoes for movement in parallel motion thereby changing the disk shoes.

Disclosed is a walking beam and more particularly its driving mechanisms whereby a material placed on a plurality of stationary beams for transfer, e.g., a steel product such as a steel pipe or round bar is raised from below, moved forward and lowered again onto the stationary beams by a plurality of transfer beams and this process is repeated to effect the transfer of the material. Each of the driving mechanisms includes a first link for causing the transfer beam to make a circular motion and the first link is rotatable about a supporting shaft with a radius of rotation l. The supporting shaft is fitted in the forward end of a second link and is rotatable about a main rotating shaft with a radius of rotation 2l. Mounted also on the supporting shaft is a first gear which is rotatable along with the first link and the first gear is in mesh with a second gear mounted on the main rotating shaft. The driving of the second gear and the second link is controlled selectively such that one of them is driven and the other is locked or both of them are driven and in this way the feed length of the transfer stroke of the transfer beam is changed to 2l, 4l or 6l.

Growing community of inventors

Yokohama, Japan

Shinji Akita