Note: Descriptions are shown in the official language in which they were submitted.
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PARTING ADJUSTMENT SYSTE:M FOR HOUSINGLBSS ROLL STAND
BACKGROUNI~ C)F THE 1~1VI~I~T~ON
1. Ficld ~f ~he Invcntion
This invention rela~es generally to rolling mills. and is concerned in particular wi~h an
improved systcm for adjllsting the roll parting between rolls in so-called "housingless st~nds".
2. Description ot` the Prior Art
In the convcntional housingless sta~nd, the ends of a pair of rolls arc journallcd for
rotation in bearings containcd in chock assemblics, and the chock assemblies on ~ach sidc of the
roll st~nd are interconnected by pairs of screw shafts which take up the roll scp~rating forces
during rolling. The screw shafts have opposite hand ~hreaded sections and arc contra-rotatcd
to effect parting adjustmcnts between the rolls.
One problem encountcred with known housingless stands is that two differently
configured screw shafts are required to make up the pairs on each side of the roll stand. For
example, in a horizontal mill, one screw shaft will typically have lett and right hand thrc~ded
sections engaged respectively with the uppcr and lower chocl; assemblies, whcrc~s ~he o~her
screw shaft will be oppositely configurcd with right and left hand threaded sections engaged
respectively with the same chock assemblics. The need to provide differently contigured screw
shaRs unnecessarily complicates maintenance procedures, and also adds significantly to spare
parts inventory expenditures.
A further problem with conventional designs is that the screw shafts are powered by
unnecesc~rily complicated drive mech~nisrns including large gear boxes which impede ready
access to the roll stand and which also interfere with close stand sp~ring along the mill pass line.
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An objecl of the present invention is provide an improv~d l~ousingless stand where roll
partin~ is controlled by pairs o~ iden(icall~ configured ~crew shaf~s on each side of ~he mill pass
line.
A companion objec~i-e of ~he present invention is to simplify ;md reduce ~he physic~l size
of ~he drive mech~nisms used ~o power the screw shafts.
SVMMARY OF THE lNVENTlON
According to the present invention, a llousingless roll stand has parallel llrst and second
rolls extending transversely with respect to the mill pass line. The roll ends of the first roll are
joumalled for rotation in bearings contained in first chock assemblies. and the roll ends of the
second roll are similarly journalled for rotation in bearings contained in second chock
assemblies. Each of the first chock assemblies is arranged adjacent to a second chock assembly
on a réspeetive side of the mill pass line. Identically configured screw shafts interconnect ~he
adjacent first and seeond chock assemblies. The screw shafts each have a first ~hreaded ~ec~ion
thrcadedly engaged wi~h a respectivé first chock assembly and ~n opposite hand second ~hreaded
sec~ion ~hre~dedly engaged with the respective second chock assembly. A drive sys~em
simultaneously rotates ~he screw shatts of each pair in a common direction in order to effect roll
parting adjustments.
Preferably, the screw shafts of each pair are rotatably supported by and axially fixed with
respect to shelf members interposed between the adjacent first and second chock assemblies.
The shelf members are supported on and removably secured to pedest~ls located on opposite
sides of the rolling line.
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The drive system used to etf~ct roll parting adjustments preferably comprises pinion gears
carried on each of the screw ~h~fts. The pinion ge~rs of e~ch pair of screw shafts are in meshed
relationship with third pinion gears interposed therebetween, and ~ worm gear is arranged
coaxially with ~nd rotationallv fixed with respeet to each of the third pinion gears. Each of the
worm ge~rs is in meshed rel~tionship wi~h a worm carried on a common rota~ble drive shaft.
I~RIF:F DF:SCRII~ION ~F THF: I)RAWIN('.S
Figure I is a front view of a housin~less roll stand embodying the concepts of the present
invention.
Figure 2 is a side view of the roll stand shown in Figure 1, with portions of the facing
support pedestal, chock assemblies and shelf member broken away in order to better illustrate
internal components;
Figure 3 is a top plan view of the roll stand shown in Figures I and 2;
Figure 4 is a seetional view taken along line 4-4 of Figure 3, with the chock assemblies
shown in broken line outline form;
Figure 5 is a seetional view taken along line 5-5 of Figure ~; and
Figure 6 is a diagrammatic three dimensional view of the serew shafts and the associated
drive rneehanisms.
DETAILED DESCRIPT10~1 OF PREFERRED EMBOD~ME!~T
Referring now to the drawings, a housingless roll stand aeeording to the present invention
is shown at 10. The roll stand includes parallel first and seeond rolls 12, 14 extending
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transversely with respecl to the mill pass line "P". rhe roll ends of the first roll 12 are
joumalled for ro~tion in bearings 16 con~ined in first choek ~ssemblies 18, ~nd ~he roll ends
of the seeond roll 14 ~re similarly journalled for ro~tion in bearings 16 con~ined in second
choel; assemblies 20.
Eaeh of the first choek assemblies 18 is arranged adjacent to a second chocli assembly
20 on a ~s~eetive side of the pass line P. The adjacen~ first and seeond chock ~ssemblies are
intereonneeted by pairs of identically configured screw shafts 2 Each screw shat't ineludes ~n
upper left hand thrc~ded section 22a, an intermediate cylindrical section ''b, ~nd a lower right
hand threaded seetion 22c.
The upper left hand threaded seetions are threadedly eng~ged with let`t hand nuts 4
housed within the first choek assemblies 18, and the right hand thrcaded seetions are likewise
threadedly engaged in right hand nuts 26 housed wlthin the seeond choek assemblies '0. The
intermediate eylindrieal seetions 22b are axially fixed with respeet to and journalled for rotation
in shelf members 28. The shelf members are in turn carried on support pedestals 30 to which
they are removably seeured by swivel bolts 32.
Any baeklash between the threaded serew shat't seetions .a, '2e and their respective nu~s
24, 26 is taken up by hydraulie piston-cylinder units 34 extending be~ween and connected at their
opposite ends to the first and seeond chock assemblies 18, 20.
Eaeh serew shaft 22 protrudes upwardly into one of two gear boxes 36 where it is
provided with a pinion gear 38. The pinion gears 38 of eaeh pair of serew shafts are in meshed
rela~ionship with a third pinion gear 40 interposed therebetween and earried on an interme~i~t~
stub shaft 42. A worm gear 44 overlies each third pinion gear 40 and is keyed or otherwise
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connected to the stub shaft 42 for rotation therewith.
The worm gears ~4 on ~ch sidc of the mill pass line P mesh with worms ~6 carried on
a drive shaft ~8 extcnding betwcen the ge~r boxes 36 in a direction transversc ~o ~he mill pass
linc P. The drive shaft ~8 may be powcred by any convenient means, including tor cxample an
electric drive motor 50 carricd on one of the gear boxes 36.
The parting between rolls 12, 14 is adjusted by rotating drive shaft ~8 in either a
clocliwise or counterclockwise direction, depending on whether the rolls arc to be opencd or
closcd. The separating forccs excrtcd by the hydraulic piston-cylinder units 34 arc ovcrriddcn
by the forccs generated by the screw shafts 22 on the chock assemblics 18, 20.
Since the screw shafts ' are all rotated in a common direction, they can bc idcntically
configured, i.e., provided with the same arrangement of opposite hand threaded sections. This
simplifies maintenance and minimizes inventory costs.
The gearing arrangement driving the screw shafts 22 enables the size of the gear boxes
36 to be minimized, thereby facilitating a close spacing of roll stands along the mill pass line.
More panicularly, as shown in Figure 6, using the distance "C" between the axcs of thc screw
shaft pairs as a base measurement, the gear boxes 36 can have a width "W" of approximately
C/2 and a length "L" of approximately 3C12. This compact arrangement is further beneficial
in that it also facilitates maintenance by allowing the area overlying the rolls to remain
uncluttered and thus readily accessible to operating personnel.
I claim:
