摘要:
A method and apparatus for torque equalization on the drive of a rolling stand, having a linear oscillatory movement driven via a crank drive, of a Pilger step-by-step rolling mill, particularly a cold Pilger rolling mill. In order to avoid the inefficient and/or expensive drive and to create a torque equalization system which avoids generator operation of the motor of the drive device of the mill and therefore torques acting in the direction of rotation of the motor on the motor, the variation of speed of rotation of the crank drive, determined mathematically from the kinematic parameters of the system, the masses moved and the external loads, is imparted to the crank drive as a desired variation of speed of rotation.
摘要:
A cold pilger rolling mill includes a reciprocating roll stand and a crank drive connected to the roll stand through connecting rods. The crank drive includes three shafts arranged parallel to each other and spaced apart at equal distances. The middle shaft is a crank shaft connected through crank pins with the connecting rod. A main weight for balancing half of the inertia forces of the roll stand is arranged eccentrically relative to the axis of rotation on the crank of the crank pin offset by 180.degree. from the pivot point of the connecting rod. On the two other shafts are arranged two additional weights of equal size which balance the other half of the inertia forces of the roll stand. For a synchronous rotation of the shafts and their weights, the shafts are connected by spur gears meshing with each other in such a manner that the additional weights rotate in opposite directions to the main weight with the same rate of rotation and, at the dead centers of the roll stand, the sum of the main weight and the additional weights acting on the roll stand corresponds to the inertia forces of the roll stand and of any other weights moved with the roll stand.
摘要:
A bearing construction for a crankshaft of a cold Pilger rolling mill for the rolling of tubes wherein the connecting rod is attached to the mill and in which case friction is created between an abrasion bushing made from surface-hardened steel and a bearing box made of high-load or strength synthetic material. For the lubrication of the friction surfaces, the cooling fluid employed for rolling is used. For better removal of heat, the abrasion bushings are provided with means such as cooling fins or similar surface-enlarging profiles and/or materials with high thermal conductivity.
摘要:
A spur gear assembly for axially mounting and supporting an end of a feed screw for each carriage and is driven from the main drive, since these feed screws of each carriage are arranged coaxially along a line parallel to a passline of the pilger mill. This spur gear allows relative rotation of the feed screws in this gear assembly mounting and a similar mounting is provided for the other screws of the pair of screws for each carriage. A first gear unit connected to the main drive causes a reciprocation of the stand along with the two feed carriages, and a second gear unit including a shaft clutch assembly is selectively brought into engagement and disengagement with the spur gear assemblies and the first gear unit to impart rotation to the screws to separately and independently advance and return the feed carriages to their starting position while one of the feed carriages continues to advance the shell through the mill.
摘要:
The disclosure relates to a workpiece feed apparatus for cold pilger rolling mills having at least one feed spindle for at least one feed carriage, and having a feed transmission which is connected to the main drive and comprises two branches or lines of drive, of which the first line of drive is connected with a gear wheel secured on the feed spindle for producing a continuous rotational movement of the feed spindle, and the second line of drive is connected by way of an intermittently moved lever with the feed spindle for the purpose of producing an intermittent axial movement of the feed spindle.
摘要:
An arrangement for securing and easily releasing a mandrel from a mandrel rod upon their advancement and return movements during the piercing operation of a seamless tube. Between the mandrel and rod is an intermediate piece having one or more openings for receiving a hook with a nose extending into an opening of the mandrel. The hook is biased into position by a spring mounted around its one end and at its other end beneath a nose is a tapered surface for contacting a corresponding surface of the mandrel to pivot the hook away from the interior of the mandrel to release the mandrel from the intermediate piece and mandrel rod.
摘要:
A forward feed gear mechanism for a cold pilger rolling mill having at least one forward feed slide, whose advancing movement can be derived from at least one forward feed spindle which is driven in continuous rotation, and an oscillating axial movement can be superimposed on the rotational movement of the forward feed spindle so that the gear mechanism is flexible and adaptable to different settings and provides high acceleration values with a simplified gear unit design. A planetary rolling spindle is provided for generating the axial movement of the forward feed spindles and is coaxially connected with one end of the forward feed spindle so as to be independently rotatable. The housing of the rolling spindle is rigidly arranged in the forward feed gear mechanism housing and the planetary rolling spindle can be driven in rotation in a translatory manner by a separate drive via a spur gear unit stage.
摘要:
The disclosure of the present invention relates to a compensating counterweight system used in a cold pilger step-by-step type seamless tube rolling mill reciprocated by a crank assembly. The crank assembly includes first and second compensating mass devices which are arranged to rotate coaxially on a single crank shaft in opposite directions relative to each other. The two mass devices are kinetically connected through a bevel gear drive set which causes the second compensating mass device to rotate in an opposite directon to the first compensating mass device.
摘要:
The disclosure of the present invention concerns a piercing rolling mill with a mandrel changing device which has at least two groove-like recesses which can be positioned alternately in the rolling line in order to hold the mandrels, and a retractable mandrel stripper, and where the mandrel rod carries at its front end a pin on which the mandrel is attached in such a way that it is detachable against the effect of expanding springs or similar means.