摘要:
At the outlet of a hot rolling mill the temperature of a hot rolled rail is reduced to a value not lower than that at which the pearlitic transformation begins in the rail head. The continuously moving rail is then rapidly cooled to below 650.degree. C. so that at least 80% of the austenite-pearlite transformation has occurred at the end of rapid cooling. The rail is then cooled to ambient temperature.
摘要:
At the exit from the hot rolling mill the rail temperature is reduced to a value not less than that at which the pearlite transformation begins in the rail head. From this temperature the continuously advancing rail is subjected to rapid cooling in a rapid cooling line. Subsequently the rail is cooled to ambient temperature. For a given rail head temperature at the extreme to the rapid cooling line, the length of the line, the speed of advance of the rail, and the average thermal flux density applied to the head, flange, and web of the rail are controlled so that the final mechanical properties of the rail head are obtained, although less then 60% of the cross-section of the head has undergone the austenite-pearlite transformation upon leaving the rapid cooling line, and differences in elongation between the head and the web and between the head and the flange are minimized.
摘要:
This invention relates to an offset printing apparatus, which comprises a frame and a removable cassette comprising a plate cylinder and a blanket cylinder, with parallel transverse axes, tangential to each other and adapted to be engaged in the frame of the apparatus so that the plate cylinder is in contact, under pressure, with each inking roller with a predetermined touch, i.e. a predetermined crushing of the peripheral layer, of supple material, of the inking roller. This touch is determined by a first bearing element or touch way, associated with each bearing of an inking roller and, on each removable cassette, a second bearing element or touch way. In order automatically to obtain the correct touch when a cassette is changed, the second touch way of the cassette is constituted by a fixed disc bearing a covering, forming a coating of thickness equal to that of the covering associated with the plate.
摘要:
Steel concrete-reinforcing rod is manufactured on a high speed rod rollingill including a finisher followed by a cooling device for superficial quenching. The traction applied to the product leaving the finisher and approaching the cooling device is arranged to be appropriate to the correct advancement of the rod, by increasing the drive force of the rod and/or reducing the braking forces produced in the cooling device. Braking force in the cooling device can be reduced by introducing air into the cooling water.
摘要:
The invention relates to a variable printing machine which is embodied in the form of at least two offset printing apparatus (1) and comprises a frame bearing an opposite cylinder against which a blanket (11) to be printed is pressed by a blanket drum. Printing ink is supplied to a printing cylinder which contacts the blanket drum by means of inking rollers. The inventive printing machine is characterized in the following: the opposite cylinder of each apparatus (1) is devoid of all rotatable transmissions; a levelling between two adjacent units which print one and the same blanket face (11) is embodied in such a way that said blanket is in contact with the blanket drums only.
摘要:
6-Methyl-3,4-diphenyl-3,4,5,6-tetrahydro-2-pyrone or derivatives thereof are psychostimulants which can be administered orally, parenterally and rectally. An effective oral dose for an adult is 100-1000 mg/day.
摘要:
The assembly is of the type in which the disc has a braking surface for cooperation with a brake pad and the wheel has a radially-extending web and an axial annular surface. A centering device centers the disc relative to the axial annular surface. The disc has on the side thereof opposed to the braking surface a second surface which frictionally engages a third surface defined by the wheel of the web. The second or third surface is constituted by a material having a coefficient of friction on the third or second surface which is higher than that of the braking surface of the disc on the brake pad so that, upon braking, the disc does not slip relative to the wheel.
摘要:
A device for removably fixing a sleeve (5) to a cylindrical support shaft (3) of a printing machine. The inventive device is characterised in that: the inner face (5b) of the sleeve (5) includes at least one cylindrical stiffened area (24); and the support shaft/sleeve assembly is equipped with (i) elements which, in the operating position and under the action of members that supply a clamping force (21, 32, 32′), apply at least one pressing member (15, 30, 40) against the stiffened area (24) in order to render same solidly connected to the sleeve (5), and (ii) elements which, in the mounting/disassembly position and under the action of members that supply a releasing force, release the pressing member (15, 30, 40).
摘要:
An apparatus for shaping a flexible web (2) includes, between an entry roller (5) and a forming roller (3), a regulating module (7) provided with a starting roller (13) designed to control the movement and the speed of the web upstream of the shaping roller (3) and at least one mobile guide element (9) designed to exert, at least on one buffer loop (8) of the web (2) formed between the rollers (5, 3), a positive guiding thereof, in accordance with a law of displacement which is a function of the length of the buffer loop (8) in operation.
摘要:
A variable printing machine is embodied in the form of at least two offset printing apparatus (1) and includes a frame bearing an opposite cylinder against which a blanket (11) to be printed is pressed by a blanket drum. Printing ink is supplied to a printing cylinder which contacts the blanket drum with inking rollers. The printing machine is characterized in the following: the opposite cylinder of each apparatus (1) is devoid of all rotatable transmissions; a leveling between two adjacent units which print one and the same blanket face (11) is embodied in such a way that the blanket is in contact with the blanket drums only.