DEVICE FOR ADJUSTING THE POSITION OF THE FORGING ROLLS IN A FORMING LINE

Abstract: A device for adjusting the position of the forging rolls in a forming line comprising a forging head (2) housing at least two rolls (8) each supported by a support (4), characterised in that said support is mounted on a slide (10) provided with a partition (14) slidable within a hydraulic system in such a manner as to define two separate chambers (16, 16') connected via ducts to a servovalve (22) controlled by a computer.

Description: DEVICE FOR ADJUSTING THE POSITION OF THE FORGING ROLLS IN A FORMING LINE This invention relates to a device for adjusting the position of the forging rolls in a forming line. In forming lines for rolled sections or electrowelded tubes, a known production method comprises the use of a head provided with rolls which act on the section being worked in order to deform, construct, guide or clamp it, depending on the operation to be carried out. The rolls are currently adjusted using screw and nut systems operated by wrenches which can be very large in the case of tubes of large diameter and/or thickness. These known heads have however certain drawbacks, and in particular: - it is difficult to adjust the roll position because of the considerable forces in play, - the time required to equip the head is lengthy precisely because of the difficulty of making this adjustment and/or replacing the rolls. An object of the invention is to eliminate these drawbacks by providing a device which enables the roll position to be easily adjusted using little force. This and further objects which will be apparent from the ensuing description are attained according to the invention by a device for adjusting the position of the forging rolls in a forming line as claimed in claim 1. A preferred embodiment of the invention is described in detail hereinafter with reference to the accompanying drawings, on which: Figure 1 is a front view of a welding head on which the adjustment device of the invention is mounted, Figure 2 is a side view thereof, Figure 3 is an enlarged lateral section therethrough on the line Ill-Ill of Figure 1 , Figure 4 shows the roll support bracket in its assembled state, and Figure 5 shows it in plan view. As can be seen from the figures the adjustment device of the invention is applied to a traditional welding head shown in front view in Figure 1. Although the invention is described hereinafter with reference to said welding head 2, the adjustment device can also be applied to the rolls provided for operations downstream of said welding head, for example those in "straightening heads". The adjustment device of the invention comprises, for a forming roll 6, substantially a support 4 provided with a pin 8 for removable engagement in a corresponding slide slidable within a slide carrier 12 mounted on the welding head frame 13. The slide 10 is rigid with a partition 14 housed in a cylindrical chamber, to form two chambers 16,16' provided with feed ducts 18,20 from both sides of the partition 14. The two ducts 18,20 are connected to a single servovalve 22 controlled by a computer (not shown on the drawings). The pin 8 is engaged in the slide 10 by insertion into a corresponding cylindrical seat 24, and is maintained stable in this condition by operating a latch 26 having a rack portion 28 engagable by a pinion 30 engaged with a rack piston 32. The adjustment device of the invention operates in the following manner: Having determined the diameter of the tube to be formed and chosen the appropriate rolls 6 to form this diameter, these are mounted on the support 4 which is then engaged via the pin 8 in the seat 24, this then being closed by the latch 26 by feeding oil into the cylindrical chamber 34 of the rack piston 32. To position the roll in the correct position for guiding the tube to be welded, oil is fed into the chamber 16 by means of a computer-controlled hydraulic system while at the same time oil is withdrawn from the chamber 16' so that the partition 14 and consequently the slide 10 rigid with it move until the roll 6 reaches the position set on the computer. This position is maintained stable by the action of the servovalve 22 which intervenes each time the partition tends to move from said set position. As the lower end of the support 4 is substantially in contact with the piston of a cylindrical chamber 36 at predetermined pressure, it is apparent that the rotating action due to the passage of the tube between the rolls results in a slight rotation of the support 4, which compresses said piston to cause the pressure within the chamber to vary. A suitable electrical pressure transducer therefore enables the forces in play to be measured. From the aforegoing it is apparent that the adjustment device of the invention presents numerous advantages, and in particular: - it enables the roll position to be adjusted without requiring the use of unwieldy and heavy wrenches, and hence with an ease and rapidity which enables this to be done even during welding, with no risk to the operator (accident prevention), - it enables welding to be carried out with total precision because of the ability to effect micrometric displacements of the rolls and to memorize these displacements in the computer, and use the data for future applications, - it enables the welding pressure variation to be known at every moment because of the provision of pressure gauges, - it can be controlled by a computer program, hence enabling data to be memorized for repetition in subsequent operations, - it enables the roll supports to be automatically locked.

Claims: C L A I M S 1. A device for adjusting the position of the forging rolls in a forming line comprising a forging head (2) housing at least two rolls (8) each supported by a support (4), characterised in that said support is mounted on a slide (10) provided with a partition (14) slidable within a hydraulic system in such a manner as to define two separate chambers (16, 16') connected via ducts to a servovalve (22) controlled by a computer. 2. A device as claimed in claim 1 , characterised in that said support (4) is provided with a pin (8) removably enegagable in said slide and lockable thereto by the action of a latch (26). 3. A device as claimed in claim 2, characterised in that the movement of the latch (26) is achieved by operating a pinion (30) cooperating with a rack (26) rigid with the latch structure. 4. A device as claimed in claim 3, characterised in that said pinion (30) is operated by a rack piston (32). 5. A device as claimed in claim 1 , characterised in that the end of the support (4) interacts with a pressurized chamber (36) provided with a transducer which indicates the forces in play.

Inventors: TOFFANIN ANDREA, TOFFANIN, ANDREA
Applicants: TOFFANIN ANDREA, TOFFANIN, ANDREA
Application year: 2000
Main classification: B21C37
IPC codes: B21B13, B21B31, B21B38, B21C37, B21D5