The present invention discloses an annular cooling device for large-scale cylindrical shell, which comprises a plurality of inner jet devices and outer jet devices; the inner jet devices are arranged inside the cylindrical shell along the inner periphery; the outer jet devices are arranged outside the cylindrical shell along the outer periphery; each inner jet device and each outer jet device are oppositely arranged; the inner jet devices are used for spraying cooling medium to the inner wall of the cylindrical shell; the outer jet devices are used for spraying the cooling medium to the outer wall of the cylindrical shell; and the spray ranges of each inner jet device and each outer jet device in the axial direction of the cylindrical shell are both greater than the length of the cylindrical shell.

A piercing machine includes a plurality of skewed rolls, a plug, a mandrel bar and an outer surface cooling mechanism. The outer surface cooling mechanism is disposed around the mandrel bar at a position that is rearward of the plug, and with respect to an outer surface of a hollow shell advancing through a cooling zone which has a specific length in an axial direction of the mandrel bar and which is located rearward of the plug, as seen from an advancing direction of the hollow shell, the outer surface cooling mechanism ejects a cooling fluid toward an upper part of the outer surface, a lower part of the outer surface, a left part of the outer surface and a right part of the outer surface of the hollow shell to cool the hollow shell inside the cooling zone.

A device for cooling a metal rolling stock (1) rolled in a rolling train, having multiple cooling devices (4), to which water (5) is supplied via a respective branch line (7) and by means of which the water (5) is applied to the rolling stock (1). The branch lines (7) are equipped with a respective valve (8), by means of which the water flow flowing through the respective branch line (7) is adjusted. Each of the valves (8) is paired with a drive (9), via which the respective valve (8) is actuated. The cooling devices (4) form multiple groups, each of which is paired with a dedicated pressure vessel (10) in a proprietary manner. Each pressure vessel (10) is connected to a respective feed line (12) at a respective connection point (11), and the water (5) is supplied to the branch lines (7) of the cooling devices (4) of the corresponding group via said feed line. When viewed in the flow direction of the water (5), each connection point (11) is arranged upstream of the valves (8) of the respective group of cooling devices (4).

A hot and cold composite formed square and rectangular steel tube and a production method for the same are provided. The radius of an outer corner of the square and rectangular steel tube meets the following conditions: when t is less than or equal to 6 mm, R is greater than 0 and less than 2.0 t; when t is greater than 6 mm and less than or equal to 10 mm, R is greater than 0 and less than 2.5 t; when t is greater than 10 mm, R is greater than 0 and less than 3.0 t, wherein t is the wall thickness of a straight tube part of the square and rectangular steel tube; R is the radius of each of the outer corners of the four corners of the square and rectangular steel tube; and the wall thickness of each corner of the square and rectangular steel tube is between 1.0 t and 1.8 t.

A liquid coolant (6) is fed into a header line (4) by means of a pump assembly (5). Branch lines (9a to 9d), in which control valves (11a to 11d) are arranged, branch off from the header line (4) to application units (10a to 10d). The coolant (6) is applied to a hot rolled material (2) made of metal by means of the application units (10a to 10d), and the rolled material (2) is thus cooled. For limit modulation values (kLim) of the control valves (11a to 11d), a control unit (12) of the cooling unit (3) uses setpoint flows (Ka* to Kd) of the application units (10a to 10d) to determine individual working pressures (pAa to pAd) which must prevail in the header line (4) for the setpoint flows(Ka* to Kd*) to flow in the branch lines (9a to 9d).

An apparatus line for manufacturing seamless steel pipes and tubes includes: a heating apparatus for heating a steel raw material; a piercing apparatus for piercing the heated steel raw material thus forming a hollow material; and a rolling apparatus for applying working to the hollow material to form a seamless steel pipe having a predetermined shape. A cooling apparatus is arranged on an exit side of the rolling apparatus. A heated steel raw material is worked by the rolling apparatus after being pierced by the piercing apparatus, and thereafter, using a surface temperature of a hollow piece before being cooled by the cooling apparatus as a cooling start temperature, the hollow piece is cooled to a cooling stop temperature differing by 50° C. or more from the cooling start temperature and being equal to or above 600° C. at an average cooling speed of 1.0° C./s or more in terms of an outer surface temperature.

The invention relates to a method and a rolling device for rolling a rolled material. The rolled material is guided through a roll gap between two working rollers of a reversing roll stand, alternatingly in two opposing rolling directions. A lubricant for lubricating a contact zone is introduced into the contact zone in which the rolled material is in contact with the working rollers, and a coolant is applied to the rolled material and/or the working rollers. In a mixture with a carrier gas, the lubricant is sprayed onto the working rollers and/or onto the rolled material exclusively on an outlet side of a pass. The coolant is applied to the working rollers and/or to the rolled material exclusively on an inlet side of a pass.

The invention relates to a method and a rolling device for rolling a rolled material. The rolled material is guided through a roll gap between two working rollers of a reversing roll stand, alternatingly in two opposing rolling directions. A lubricant for lubricating a contact zone is introduced into the contact zone in which the rolled material is in contact with the working rollers, and a coolant is applied to the rolled material and/or the working rollers. In a mixture with a carrier gas, the lubricant is sprayed onto the working rollers and/or onto the rolled material exclusively on an outlet side of a pass. The coolant is applied to the working rollers and/or to the rolled material exclusively on an inlet side of a pass.

An apparatus line for manufacturing seamless steel pipes and tubes includes: a heating apparatus for heating a steel raw material; a piercing apparatus for piercing the heated steel raw material thus forming a hollow material; and a rolling apparatus for applying working to the hollow material to form a seamless steel pipe having a predetermined shape. A cooling apparatus is arranged on an exit side of the rolling apparatus. A heated steel raw material is worked by the rolling apparatus after being pierced by the piercing apparatus, and thereafter, using a surface temperature of a hollow piece before being cooled by the cooling apparatus as a cooling start temperature, the hollow piece is cooled to a cooling stop temperature differing by 50° C. or more from the cooling start temperature and being equal to or above 600° C. at an average cooling speed of 1.0° C./s or more in terms of an outer surface temperature.

The invention is intended to provide a method for quenching a steel pipe, equipment for quenching a steel pipe, and a method of manufacturing a steel pipe that enable a steel pipe to be conveyed at high speed. The method for quenching a steel pipe includes the steps of: conveying a steel pipe onto a rotatable supporting member using a walking-arm type revolving conveyance apparatus; and rapidly cooling the steel pipe with first spray nozzles disposed above the pipe while the steel pipe is being rotated about a pipe axis of the steel pipe on the rotatable supporting member in a state where movements of the steel pipe in a direction parallel to and in a direction perpendicular to the pipe axis are stopped.