CLAIMS
1. A rolling mill (1) for tubular bodies comprising a first section (10) for rolling on
mandrel defined by a first plurality of rolling stands (15', 15, 15") arranged in
sequence along a rolling axis (100), characterized in that it comprises a second
5 section (20) for extracting said mandrel and calibrating the diameter of said
tubular bodies, said second section being downstream of said first section (10), whereby said tubular bodies exiting from said first section (10) directly enter said second section (20), said second section (20) comprising a second plurality of rolling stands (25', 25, 26, 27, 26', 27') without mandrel, arranged in sequence
10 along said rolling axis (100), wherein each stand (25', 25, 26, 27, 26', 27') of said
second section (20) comprises three rollers, the rotation axes of which are arranged at 120 ° relative to one another and wherein, for each stand (25', 25, 26, 27, 26', 27'), said rotation axes are rotated by 180° relative to corresponding rotation axes of an adjacent stand, said position of said rotation axes being
15 assessed with respect to a vertical reference direction, and wherein at least one
stand of said second section (20) comprises a motorized roller having a vertical rotation axis.
2. A rolling mill (1) according to claim 1, wherein said second section (20) comprises
at least one fixed rollers stand (25', 25).
20 3. A rolling mill (1) according to claim 1, wherein said second section (20) comprises at least one adjustable rollers stand (26, 27, 26', 27').
4. A rolling mill (1) according to claim 1 or 2, wherein said second section (20)
comprises a first series of fixed rollers stands (25', 25) arranged in sequence
along said rolling axis (100) starting from an inlet side (20') of said second section
25 (20), at least one of said fixed rollers stands (25', 25) comprising mechanical drive
means configured to transmit the motion from said motorized roller having vertical rotation axis to the other rollers of the same stand.
5. A rolling mill (1) according to claim 1, wherein said second section (20) comprises
at least one dummy stand (28) comprising at least one guide roller.
30 6. A rolling mill (1) according to any one of claims from 1 to 5, wherein each stand (15', 15, 15") of said first section (10) comprises three rollers, the rotation axes of which are arranged at 120° relative to one another and wherein the rotation
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axes of the rollers of an outlet stand (15") of said first section (10) are rotated by 180° with respect to the rotation axes of the rollers of an inlet stand (25') of said second section (20).
7. A rolling mill (1) according to any one of claims from 1 to 6, wherein said second
5 section (20) comprises a first stretch (21) which defines a first plurality of lodging
positions each of which configured for accommodating a fixed rollers stand or a
dummy stand, said second section (20) comprising a second stretch (22),
downstream of said first stretch (21), which defines a second plurality of lodging
positions each of which configured for accommodating a fixed rollers stand or a
10 dummy stand or an adjustable rollers stand.
8. A rolling mill (1) according to any one of claims from 3 to 7, wherein said second
section (20) comprises a group (60, 62) of adjustable rollers stands, said group
(60, 62) comprising:
- a first stand (26, 26') and a second stand (27, 27') adjacent to said first stand
15 (26, 26'), wherein said first stand (26, 26') comprises at least one roller motorized
by an actuating means;
- a transmission device (91) which operatively connects said at least one roller
(34, 35, 36) of said first stand (26, 26') to at least one roller (34', 35', 36') of said
second stand (27, 27') so that both the rollers are actuated by said actuating
20 means.
9. A rolling mill (1) according to claim 8 when depending on claim 7, wherein said
second stretch (22) of said second section (20) defines three lodging positions
and wherein said group (62) of adjustable rollers stands is configured to occupy
the first lodging position and the second lodging position downstream of said first
25 stretch (21).
10. A rolling mill (1) according to claim 8 when depending on claim 7, wherein said
second stretch (22) of said second section (20) defines three lodging positions
and wherein said group (60) of adjustable rollers stands is configured to occupy
the second lodging position and the third lodging position downstream of said first
30 stretch (21).
11. A rolling mill (1) according to any one of claims from 8 to 10, wherein said group
(60, 62) comprises at least a first transmission device (91) which operatively
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connects a first vertical axis roller (34) of said first stand (26, 26') to a first vertical axis roller (34') of said second stand (27, 27').
12. A rolling mill (1) according to any one of claims from 8 to 11, wherein said first
stand (26, 26') and said second stand (27, 27') of said group (60, 62) are
5 integrated in a single body (60') defining an operating recess inside which the
rollers (34, 35, 36) of said first stand (26, 26') and the rollers (34', 35', 36') of said second stand (27, 27') are accommodated.
13. A rolling mill (1) according to any one of claims 8 to 12, wherein said first stand
(26, 26') and said second stand (27, 27') of said group (60, 62) each comprise:
10 - a first roller (34, 34') having a vertical rotation axis (111, 111');
- a second roller (35, 35') having a rotation axis (112, 112') inclined by 120°
with respect to said vertical rotation axis (111, 111') of said first roller (34, 34'),
said second roller (35, 35') being operatively positioned above a horizontal
reference plane (105) on which said rolling axis (100) lies;
15 - a third roller (36, 36') having a rotation axis (113, 113') inclined by 120° with
respect to said rotation axes of said first roller (34, 34') and of said second roller
(35, 35'), said third roller (36, 36') being operatively positioned below said
horizontal reference plane (105),
and wherein said group (60, 62) comprises a second transmission device which
20 operatively connects said third roller (36) of said first stand (26) to said second
roller (35') of said second stand (27, 26'), said third roller (36) of said first stand
(26, 27') being actuated by an actuating means.
14. A rolling mill (1) according to claim 13, wherein said group (60, 62) comprises a
further transmission device which operatively connects said second roller (35)
25 of said first stand (26, 26') to said third roller (36') of said second stand (27, 27'),
said third roller (36') of said second stand (27, 27') being actuated by a further actuating means.
Dated this 18 day of May 2018
M. Gowthaman
REG.NO: IN/PA-1846
of Cantwell & Co.
Agent for the Applicants
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