Abstract: There is described multi-stand rolling mill with stands having four motorized rolls and provided with controls outside the stand and retractile spindles, which comprises a central body with said stands; a first platform (41) on a side charge position carrying the substitution stands; a second platform (42) on a side discharge position, opposite to said side charge position; a transversal translation device (43, 44) adapted to push the substitution stands against the corresponding stands to be substituted on the central body. The stands to be substituted translate on the second platform, and the substitution stands substitute the stands to be substituted in the central body.

Abstract: There is described multi-stand rolling mill with stands having four motorized rolls and provided with controls outside the stand and retractile spindles, which comprises a central body with said stands; a first platform (41) on a side charge position carrying the substitution stands; a second platform (42) on a side discharge position, opposite to said side charge position; a transversal translation device (43, 44) adapted to push the substitution stands against the corresponding stands to be substituted on the central body. The stands to be substituted translate on the second platform, and the substitution stands substitute the stands to be substituted in the central body.

Abstract: A process for producing a hollow billet for producing tubing for antifriction bearings includes massively reducing a bloom in a three-roll rotary piercing mill and subsequently piercing the reduced bloom in a three-roll rotary piercing mill. The reducing and piercing may be performed in one-pass through the three-roll rotary piercing mill. The reducing and piercing steps may also be performed in separate passes through the same mill or through two separate mills.

Abstract: A multi-stand roll train for longitudinally rolling seamless steel tubes in a continuous rolling process around an internal die using integrated two-high stands staggered by 90.degree. with correspondingly grooved rollers. The rollers are radially adjustable relative to one another, and at least the rollers of the final roll stand in the direction of rolling are divided along a central plane which vertically intersects the axis of the roller to form two halves. The two halves of the divided roller are axially adjustable relative to one another.

Abstract: For the inhalation of agglomeratable pulverulent medicaments and the like, there is disclosed a multi-chamber inhalator containing a storage chamber having an agglomerate comminutor and a porous distributor plate at one end (about 5-100 micron pore size) so that only desired particle size powder may pass through; an atomization chamber having a porous retention screen (the mesh being smaller than that of the distributor plate) for receiving the desired particle size powder; and a mouthpiece for inhaling powder from the atomization chamber.