US3344643A

US3344643A - Rolling mills

Info

Publication number: US3344643A
Application number: US321951A
Authority: US
Inventors: Howard David Robert; Stubbs Dennis; Swallow Reginald Dennis
Original assignee: Davy Loewy Ltd
Current assignee: Davy Loewy Ltd
Priority date: 1961-11-08
Filing date: 1963-11-06
Publication date: 1967-10-03
Anticipated expiration: 1984-10-03
Also published as: DE1269981B; BE639627A; FR1354831A; NL285161A

Description

Filed Nov. 6, 1963 5 Sheets-sheaf 1 Hal. I!

4 INVENTOQS DAVID R-HOWARD DENNIS STUBBS 8 REGINALD D.SWALLOW THEIR Oct 1967 D. R. HOWARD ETAL 3,344,643-

ROLLING MILLS Filed Nov. 6. 1963 I. 5 Sheets-Sheet 2- \IENTOR-S In DAVID R. HOWARD DENNIS s'russs REGINALD D. SWALLOW ElR ATTQRNEY 06L 1967 D. R. HOWARD ETAL 3,

ROLLING MILLS 5 Sheets-Sheet 3 Filed Nov. 6, 1965 FIG. 3.

INVENTOQ DAVID R HOWARD DENNIS STUBBS 8. REGINALD D. SWALLOW Oct. 3, 1967 D. R. HOWARD ETAL 3,344,643

ROLLING MILLS Filed Nov. 6, 1963 I 5 Sheets-Sheef 4 INVENTORS DAVID R. HOWARD, DENNIS STUBBS 8 REGINALD D. SWALLOW Oc 1967 D. R. HOWARD ETAL 3, 4, 43

ROLLING MILLS Filed Nov. 6, 1963 5 Sheets-Sheet 5 lNvEN'roRS DAVID R-HOWARD, DENNIS STUBBS 8: REGINALD D.SWALLOW n HEIR ATTORNEY United States Patent 3,344,643 ROLLING MILLS David Robert Howard and Dennis Stubbs, Sheffield, and Reginald Dennis Swallow, Todwick, near Sheflield, England, assignors to Davy and United Engineering Company, Limited, Shefl'ield, England Filed Nov. 6, 1963, Ser. No. 321,951

Claims priority, application Great Britain, Feb. 7, 1963,

13 Claims. (Cl. 72-237) This invention relates to rolling mills and in particular to means for allowing self-alignment of the roll-neck bearing assemblies which are supported by the housing structure of the rolling mill.

Consider a rolling mill having at least two parallel rolls. Certain of these rolls, which are for convenience herein referred to as load-transferring rolls, are designed to transfer the rolling load, to which the mill rolls are subjected when the mill is in use, to the housing structures of the mill. In the case of a Z-high mill, each of the two rolls acts as a load-transferring roll; in the case of a rolling mill with more than two parallel rolls, the outermost rolls are commonly arranged to act as load-transferring rolls.

Each load-transferring roll is commonly provided with a pair of roll-neck bearing assemblies, by which is meant the necks of each such rolls together with the associated radial-type bearing assemblies. The roll-neck bearing assemblies are mounted within the housing structure of the rolling mill, and it is through these roll-neck bearing assemblies that the rolling load is transferred from the rolls of the mill to the housing structure.

When a rolling mill is in use, the rolling load tends to cause the load-transferring rolls to bow. Unless provision is made for the roll-neck bearing assemblies of the loadtransferring rolls to self-align, that is to undergo suitable rotational movement in accordance with the bowing of the load-transferring rolls, bending moments are set up in the roll-neck bearing assemblies and the housings. Such bending moments produce a lead distribution on the roll-neck bearing assemblies which is non-uniform in an axial direction and which will tend to lead to premature failure of the bearing assemblies. In extreme cases they might also produce fracture of the roll-necks of the loadtransferring rolls.

The invention provides a rolling mill having a housing comprising first and second members, each arranged to support a roll neck bearing assembly, means for prestressing the housing members together, hinging devices between the housing members, each hinging device including at least one member having curved upper and lower surfaces held in compression between curved surfaces between the housing members, so as to allow the housing members to pivot relative to one another about an axis parallel with the pass line of the mill.

Each hinging device may include a roller held in compression between, and cooperating with, curved recesses in plates. Each hinging device may further include a resilient sealing member which is located between the plates and arranged around the rollers.

Each hinging device may be made as a separate unit, the two halves of which are secured together, and to the lower housing member, by bolts. Coil springs may be located in recesses in the upper surface of the upper plate, and abutting the head of the bolts, to hold the various integers of the hinging device together, so that the hinging device can be transported as a unit.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings of which:

FIGURE 1 is an end elevation of a 2-high prestressed rolling mill with the drive arrangement omitted,

3,344,643 Patented Oct. 3, 1967 FIGURE 3 is an enlarged sectional elevation along the line III-III of FIGURE 2,

FIGURE 4 is a sectional elevation along the line IV IV of FIGURE 3,

FIGURE 5 is an enlarged isometric view of the seal shown in FIGURE 4.

Referring first to FIGURES 1 and 2, the rolling mill has at each side a housing structure formed in two principal parts, an upper housing member 10 and a substantially U-sha-ped lower housing member 11. The lower housing member 11 is provided with arms 12 which rest upon projecting portions 13 of a platform 14 secured to a foundation structure by bolts, the axis of which are indicated at 15. The arms 13 of the housing member 11 are secured to the platform 14 by bolts 16 having a slot 17 through which is passed a wedge 18 engaging a collar 20. The projecting portions 13 of the platform 14 also constitute a slideway so that the rolling mill may be moved transversely of the rolling path in order to align the rolls with the rolls of an adjacent mill stand. This transverse movement is accomplished by providing the lower housing member 11 with a coupling 21 which is engaged by a similar coupling 22 arranged on the end of a piston rod 23 of a piston and cylinder arrangement (not shown).

The housing members ltl and 11 are prestressed together by means of bolts 24 which extend through bores in the housing members. Each bolt 24- is provided with a nut 26 at its upper end and a nut 27 at its lower end. Each of the bolts 24 passes through two bushing members 28 (FIGURE 3) one of which is located above and below a hinging device 30. The bushing members 28 are provided to locate the bolt 24 in a substantially vertical position and are made of softer material than the bolts 24 in order that the threads on the bolts will not become damaged when placed in position within the housing members. Sufiicient clearance is provided between the bolts 24 and the bushing members 28 so as not to hinder the pivotal movement of the upper housing member 10 relative to the lower housing member 11 when a rolling load is applied.

remove the upper housing member 10 the nuts 26 are removed from the bolts 24, Whereafter the housing member 10 may be withdrawn by inserting crane hooks in the links 33.

The upper housing members 10 support roll neck bearing assemblies 29 of an upper roll 34, whereas the lower housing member 11 are provided with separate chocks 35 to support roll neck bearing assemblies 39 of a lower roll 36. To adjust the roll gap of the rolling mill, the chocks 35 may be moved vertically by rotation of a shaft 37 having oppositely threaded portions 38 upon which are mounted a pair of threaded wedges 40, arranged to engage with the lower surfaces of a second pair of wedges 41. Between each wedge 41 and the lower surface of each chock 35 is a segmental pad 42 which bears upon a suitably hardened member 43 arranged in the upper surface of the wedge 41. This allows the chock 35 to pivot relative to the lower housing member 11.

The

rolls

34, 36 may be adjusted axially relative to each other, by rotation of a double ended screw 44 into which are threaded

arms

45 and 46, which arms have at their opposite ends link

members

47 and 48. The

link members

47 and 48 are pivotally mounted near their ends remote from the double ended screw 44 on a common pivot pin (not shown) arranged in lugs 50 extending from the housing member 11. The ends of the

link members

47 and 48 are arranged to engage an extension 51 provided on the chock 35. By rotation of the double ended screw 44 the

link members

47 and 48 will pivot about the pin and will act upon the extension 51 of the chock 35, thus axially adjusting the lower roll 36 relative to the upper roll 34.

The lower ends of the limbs of the upper housing member 10 has projections 52, and the upper end of the limbs of the lower housing member 11 has projections 53, which projections extend near to the centre line of the upper roll 34.

Between the

extensions

52, 53 are arranged the hinging devices 36, which may best be seen in FIGURES 3 and 4 of the drawings.

Each hinging device comprises a pair of rollers 54 situated one at each side of their associated bolt 24. The rollers 54 are held in compression between cylindrical recesses 55 of

plates

56, 57. Plate 56 bears against the projection 52 of the upper housing through a packer 58, while the plate 57 bears directly against the lower housing member 11. Flanges 6t), 61 are formed on the

plates

56, 57 respectively which engage their respective housing members.

Between the

plates

56 and 57 is provided a resilient seal 62 which is arranged around the rollers 54. The seal 62 (see FIGURE has a central bore 63 into which is blended, at each side, a longitudinal slot 64; the bore 63 is provided for a passage of the bolt 24, whilst the longitudinal slot 64 are provided for the rollers 54. Two segmental members 65, of the same material as the seal, are secured to one end of the seal by a suitable adhesive. Cover plates 66 (FIGURE 3) are arranged at each side of the housing members, and these cover plates are secured to the

adjacent plates

56, 57 by bolts (not shown).

Each hinging device 30 is secured to the lower housing member 11 by means of bolts 67 (FIGURE 4) extending through the plate 56, the seal 62 and the plate 57. The bolts 67 have a head 63 at their upper ends, and at their lower ends threaded portions which are screwed into similarly threaded portions 70 of the housing member 11. The bolts 67 are provided, above their threaded portions, with a circlip 71 which retain the various parts of the hinging devices to the bolts 67 so that the hinging devices can be removed as a unit. Located in recesses 72 of the plates 56 are coil springs 73 upon which bear spring retainers 74, the springs 73 being provided to hold the integers of the hinging device together while the device is being transported.

Tapped holes 75 are provided in the upper surface of the plates 56 to facilitate lifting of the hinging devices.

Lubricant may be supplied to the rollers 54 via the

bores

76, 77 which extend through the

plates

56, 57 to the recesses 55.

In operation, the

rolls

34, 36 are subjected to the rolling load and consequently these rolls tend to bow in the direction of the arrows 70, (FIGURE 2). The roll neck bearing assemblies transmit the rolling load to the upper housing member and the chock 35 respectively and, 'because of the bowing of the

rolls

34 and 36, the roll neck bearing assemblies will tend to undergo pivotal movement in the direction of the arrows 71.

Because of the hinging devices 30 situated between the limbs of the housing members 10 and 11, the upper housing members 10 are permitted to undergo pivotal movement about axes parallel to the pass line of the mill relative to the lower housing members 11, about the hinging devices. This relative movement permits a degree of self alignment to the upper roll neck bearing assemblies.

Furthermore because of the arcuate under surfaces on the supports 42 the chock 35 can undergo pivotal movement relative to the lower housing member 11 allowing a degree of self alignment to the lower roll neck bearing assemblies.

It will be appreciated that with the above-described arrangement, the load on the hinging devices decreases as the rolling load increases.

In accordance with the provisions of the patent statutes, we have explained the principle and operation of our invention and have illustrated and described what we consider to represent the best embodiment thereof. However, we desire to have it understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

1. A rolling mill having first and second roll neck bearing assemblies, a first housing member constituting a support for said first bearing assembly, a second housing member arranged to support said second bearing assembly, hinging devices interposed between said housing members located at a position along the axis of said first bearing assembly, and means for prestressing together said housing members, each said hinging device including at least one hinge member having curved upper and lower surfaces held in compression between curved surfaces between said housing members, so as to allow said housing members to pivot relative to one another about an axis parallel with the passline of the mill.

2. A rolling mill according to claim 1 in which each hinge member having curved upper and lower surfaces comprises a roller held in compression between part cylindrical recesses.

3. A rolling mill according to claim 1 in which each hinging device includes two rollers, arranged on either side of a prestressing bolt and held in compression between part-cylindrical recesses.

4. A rolling mill according to claim 1 in which each hinging device further includes two plates held in compression between the housing members and being formed with curved recesses with surfaces complementary to said curved surfaces of said hinge member.

5. A rolling mill according to claim 4 in which each hinging device includes sealing means between the two plates.

6. A rolling mill according to claim 1 in which each hinging device is removable from the mill as a unit.

7. A rolling mill according to claim 4 in which the two plates are held in compression by a bolt, coil springs being included to hold the plates together for transportation, such that the hinging device may be removed from the mill as a unit.

8. A rolling mill according to claim 6 including means for securing each hinging device to one of the housing members.

9. A rolling mill according to claim 8 in which each hinging device is formed with flanges which engage with projections on the other housing member.

10. A rolling mill according to claim 4 in which each plate is provided with flanges which engage with projections on its associated housing member.

11. A rolling mill according to claim 1 in which said second bearing assembly is carried in a second chock vertically adjustable relative to said second housing member, and including means for allowing the lower chock to pivot about an axis parallel to the pass line, relative to the second housing member.

12. A rolling mill having first and second roll neck bearing assemblies, a housing comprising a first housing member constituting a support for said first bearing assembly, a second housing member arranged to support said second bearing assembly, means for prestressing together the first and second housing members, and hinging devices between said housing members and located at a position along the axis of said first roll neck bearing assembly, permitting relative hinging of said housing members about an axis parallel to the pass-line of the mill.

13. A rolling mill having first and second roll neck bearing assemblies, a first housing member constituting a support for said first bearing assembly and formed with shoulders, a U-shaped second housing member hav- 5 6 ing a pair of arms and supporting said second hearing as- 1,741,405 12/ 1929 Coe i 72237 sembly, hinging devices, and means for prestressing to- 2,123,754 7/1938 Talbot 72,237 gether said first and second housing members with said 2,312,648 3/1943 Jones 72-237 hinging devices interposed between said arms and said 2,601,793 7/ 195 Wood 72245 shoulders, said hinging devices being located at a position 5 3,217,525 11/ 1965 Howard 72-237 along the axis of said first bearing assembly and permitting relative hinging of said housing members about an O EIGN PATENTS axis parallel to the pass-line of the mill. 940,583 3/1956 Germany.

References Cited UNITED STATES PATENTS 1,054,920 3/ 1913 Johnson 72 -246 10 CHARLES W. LANHAM, Primary Examiner.

G. P. CROSBY, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,344,643 October 3, 1967 David Robert Howard et a1.

It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, line 39, "lead" should read load Column 4, line 58, "the lower" shouldread said second Signed and sealed this 4th day of November 1969.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer