Metal deforming – By three or more coacting relatively movable tools – Concurrently actuated tools
Patent
1991-04-15
1992-09-29
Crane, Daniel C.
Metal deforming
By three or more coacting relatively movable tools
Concurrently actuated tools
72407, 72206, 72416, B21J 1302, B21B 1500
Patent
active
051505991
DESCRIPTION:
BRIEF SUMMARY
This invention relates to apparatus for reducing the width of a hot metal slab.
For the manufacture of metal strip, such as strip steel, it is becoming increasingly common to continuously cast a workpiece in the form of a slab, to cut the slab into lengths and to roll each length into strip. Because strips of different width are required, it is desirable that slabs of different width should be available. If these slabs are to be cast in a continuous casting machine, it is not convenient to have a number of moulds, each representing a slab of different width. It is desirable, therefore, to cast slabs of a limited number of widths and, where necessary, to reduce the width of the slab to a predetermined value and to subsequently roll the slab into strip.
In a method of reducing the width of a hot metal slab, which initially has a width dimension greater than its thickness dimension, the hot slab moving in the direction of its length is presented to a pressing machine by which forces are applied to the opposite edges of the slab to reduce the width dimension of the slab along its length.
Normally the slab will be of a much greater length than the region over which the forces are applied by the platens. For this reason, the slab is incremented through the pressing machine so that its width dimension is reduced stepwise along its length by repeated application of the forces. Thickening of the slab which accompanies each width reduction by the forces can produce a non-uniform cross-section if the increment is too long. This is undesirable and can be alleviated by reducing the increment to less than the length of the slab regions affected by each application of the forces. After the reduction in the width dimension of the slab, it is convenient to roll the slab between a pair of horizontal rolls of a rolling mill.
One of the disadvantages with this method of reducing the width dimension of a slab is that, if the width to thickness ratio of the slab is greater than about 3:1, the slab will tend to buckle rather than to deform when the pressure is applied to the opposite edges of the slab.
It is known to provide an anti-buckling restraint adjacent a face of a hot metal slab which is being pressed between a pair of platens of a pressing machine. The restraint is of a fixed size and is satisfactory for slabs of a particular size but, if a slab of a different size is pressed, the restraint has to be replaced with an appropriately sized restraint.
It is an object of the present invention to provide pressing apparatus in which this difficulty can be overcome.
According to the present invention, a pressing machine for reducing the width of a hot elongate metal slab comprises first and second platens engageable with respective opposite edges of a slab to apply forces thereto to reduce the width dimension of the slab and a restraint which, in use, is adjacent a face of the portion of the slab which is between the platens so as to control the buckling of the slab in the direction towards the restraint, characterised in that the platens are positioned one above the other and, in use, are engageable with respective upper and lower edges of the slab which is arranged with its width dimension substantially vertical and the dimension of the restraint in the vertical direction is variable so as to accommodate slabs which, before pressing, are of different width dimensions.
The slab may buckle sideways in one or other or both horizontal directions when the pressing forces are applied to the opposite edges. Steps are taken to either try to prevent buckling of the slab in both sideways directions, in which case a restraint is positionable adjacent each of the faces of the slab, or steps can be taken to encourage the slab to buckle in one sideways direction only and, in this case, a restraint is required adjacent that face of the slab which is facing the direction in which buckling is encouraged to take place. The restraint serves to control the amount of buckling.
In use, the or each restraint is of sufficiently rigid construction an
REFERENCES:
patent: 2947344 (1960-08-01), Springer
patent: 3597958 (1971-08-01), Gross
patent: 5000026 (1991-03-01), Pahnke
Bradshaw Timothy J.
Lawson Kenneth T.
Wilson Geoffrey
Crane Daniel C.
Davy McKee (Sheffield) Limited
LandOfFree
Treatment of metal slabs does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Treatment of metal slabs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Treatment of metal slabs will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1962418