A microwave heating system heats a hermetic container loaded with a heated object. The hermetic container is accommodated and given pressure by a microwave transparent and pressure resistant module, and is fixed onto a transporting device in a cyclic course. Microwave is generated by a microwave heating device to perform heating. The hermetic container is stirred while the transport device carries and moves the hermetic container. The temperature of the hermetic container or the heated object is measured by a temperature measuring module. The number of times to stir and repeatedly heat the heated object are appropriately determined in the design of the system. The output power and heating time of the microwave heating device and the transmission speed of the transporting device are adjustable during operations of the system, hence forming a closed-loop temperature control system.

Guide roller including a bearing journal at each of two ends. Each bearing journal is provided with a plain bearing designed as a hollow journal, and can be connected to the coolant supply line to conduct coolant through the hollow journal into or out of the coolant channel. The plain bearing is lubricated by coolant conducted through the bearing journal. A roller assembly for a strand casting system is provided with a plurality of guide rollers. The guide rollers are arranged at an axial distance from each other along a strand produced by the strand casting system and are each rotatably supported in a respective bearing mount. Each bearing mount is arranged on at least one frame part in a preloaded manner The bearing mounts are supported on the frame parts so as to be self-setting by elastically pliable connecting structure.

The present invention relates to a water-cooled handling roll (100) for handling a load (50), in particular a thin slab, in a furnace for temperature heating, maintaining and for buffering, arranged between casting and roughing, in a continuous casting and rolling process for thin carbon steel slabs. The roll (100) comprises a first internally hollow shaft (110), which is coated by an insulating and/or refractory material and a plurality of wheels (25) connected in stably fixed manner to an outermost surface (111) of the first shaft (110) to handle and support the load (50). According to the invention, the roll (100) also comprises a second shaft (120) arranged within an inner cavity of the first shaft (110) in position coaxial to the first shaft (110) and so as to define a gap (30) between the first shaft (110) and said second shaft (120). The roll (100) further comprises cooling water circulation means housed at least in part within said second shaft (120).

A method of heat-treating tubing is disclosed which obtains desired performance characteristics, and more particularly to a method of heat-treating tubing which minimizes undesirable tinting and oxidation of the interior surfaces of tubing during heat-treatment by controlling the atmosphere within the tubing. This is achieved by purging the interior of the tubing with an inert gas, or a like protective atmosphere, as the tubing is advanced into an associated heat-treatment furnace. Notably, the purging is effected via the trailing ends of the tubing as it introduced into the heat-treatment furnace. Additionally, the method contemplates that a vacuum can be applied to the interior of the tubes during treatment in order to draw the protective atmosphere within the furnace into the leading ends of the tubing.

A hot rolled steel sheet with a yield stress greater than 690 MPa and less than or equal to 840 MPa, with strength between 780 MPa and 950 MPa, elongation at failure greater than 10% and a hole expansion ratio (Ac) greater than or equal to 50% is described. Methods for the fabrication of the sheet are also described.