GB2117689A

GB2117689A - Cold rolling stands

Info

Publication number: GB2117689A
Application number: GB08209467A
Authority: GB
Inventors: Michael Anthony Baldwin; Stephen Howard Cadney; Peter Joseph Vivian
Original assignee: Individual
Current assignee: Individual
Priority date: 1981-04-01
Filing date: 1982-03-31
Publication date: 1983-10-19
Also published as: GB2117689B

Abstract

A cold roll mill stand has rolls 3 supported in blocks 4 slidably engaging on support pillars 5. The position of the lower roll is adjusted vertically, either by means of collars 13 of various lengths, or by lock nuts 11. The position of the upper roll is adjusted by means of lock nuts 10. Springs 9 hold the blocks 4 in their working position when there is no material in the nip. <IMAGE>

Description

SPECIFICATION Cold rolling stands The present invention relates to cold roll forming mills, and in particular to roll pair supports and their adjustment.

A comprehensive background to the invention is provided by two publications and the bibliographies contained in them: "Cold Forming", W.G. Kirkland, Iron and Steel Engineer, November 1959.

"A Survey of Sheet Metal Cold Roll Form ing", M.A. Wallis, British Steel Corporation Corporate Laboratories Paper Number MW/36/71.

Existing designs of Cold Roll Forming machines generally have a fixed bottom roll (see reference 1, page 137) with a movable upper roll. This means that the bed plate of the machine and the roll pair supports have to be manufactured to fine tolerances to ensure that the bottom roll centres are all at the same height. The present invention allows the use of a light structure in the rolling mill whilst maintaining accurate positioning of the roll pair supports, thus removing the need for a heavy cast baseframe and large amounts of accurate maching on the roll pair support frames.

Furthermore the present invention allows vertical movement for both of the rolls in the pair as a whole (to adjust the relative vertical positions between adjacent roll pairs), and for each of the rolls individually (to adjust the distance between the rolls).

The present invention also allows the opposite ends of a given roll to be at different relative heights. These adjustments can be used for removing residual axial and longitudinal stresses in the rolled section which are imparted into the section during the rolling process. In contrast, known designs of Cold Roll Forming machines require some form of straightening mechanism at the end of the machine to correct any distortion in the section due to these stresses.

According to one aspect of the present invention, there is provided a roll stand, suitable for inclusion in a multi-stand cold rolling mill, said stand comprising four roll supporting members, characterized in that the relative positions of the four roll supporting members are individually adjustable. Preferably, the four roll supporting members are mounted on at least two elongate members which extend such that their principal axes are perpendicular to the roll axes.

According to a further aspect of the present invention, the four roll supporting members may be arranged in pairs, each pair being slidably engaged on one of the two elongate members. The elongate members may have adjustable stops adjacent to their ends, said stops being engageable with said roll supporting members.

The four roll supporting members may be in the form of blocks, each having at its' centre portion support means for the end of a roll, and each having at both of its' end portions a hole for engagement with one of the elongate members, there being in this case four elongate members arranged in parallel pairs adjacent to the ends of the rolls, roll supporting members engaging the pairs of elongate members for slidable movement thereon.

The elongate members may be of cylindrical form and have threaded end portions upon which engage lockable threaded means which limit axial movement thereon of the roll support members. Alternatively, the elongate members may have spacers on them to limit axial movement of the associated roll support means.

An embodiment of the present invention will now be described with reference to the accompanying drawing which shows an end elevation of a pair of roll supports for a cold roll forming machine.

The machine includes main structural members 1, 2 between which are mounted at least one and probably around four pairs of rolls 3.

Each roll 3 is supported at its ends in self aligning bearings by a roll support block 4, supported in turn by a pair of vertical cylindrical support pillars 5.

In order to minimize machining and assembly costs and still maintain the accuracy required, the following assembly procedure is adopted. Two plates 6 (four per roll pair, sixteen in a four pair mill) have accurately machined bores through them, thus ensuring that the pitch of each associated pair of support pillars 5 is closely controlled. Plates 6 are accurately aligned in the machine frame and their positions then fixed by means of dowels 7. Bolts 7a lock the pillars in place in the machine frame.

The roll support blocks 4 are movable verti cally on support pillars 5 but must of course be restrained from any significant movement in a horizontal plane (i.e. perpendicular to the longitudinal axes of the support pillars 5). This restraint may be achieved in one of three ways. Firstly, the vertical bores in roll support blocks 4 may be accurately machined to give the required fit to the support pillars 5; secondly, anciliary bushes, of a different material to the blocks, may be secured in the blocks and have the required fit to the pillars; thirdly, the vertical holes in the roll support blocks 4 may be machined to a clearance size relative to the pillars (i.e. machined to a larger tolerance) and any excess slackness in the mating be taken up by means of lockable bolts 8, whose ends contact the pillars 5.Note that these bolts take up slack, they do not lock the blocks to the pillars.

When there is no material to be rolled in the nip, roll support blocks 4 are urged apart by means of springs 9. During rolling, opening of the nip is prevented by means of a pair of lock nuts 10 threadedly engaged with the upper portions of the support pillars 5, and by either of two means at the bottoms of the support pillars.

In the first bottom adjustment illustrated in the right hand side of the drawing, downward movement of the lower support block 4 is limited by a pair of lock nuts 11, as in the upper arrangement. As an alternative, iliustrated in the left hand side of the drawing, one or more spacers 12, chosen as a set to make up a required distance (in the manner of slip gauges) are placed on the pillar 5. To facilitate changes of height without the need to disassemble the stand, spacers 12 are preferably split into two axially, and held in position by a clamping device 13.

There is thus provided a roll stand in which the nip may be varied, the height of the nip relative to other stands in the mill may be varied, and the end of a given roll or pair of rolls may be set at different heights, this being facilitated by the self aligning bearings to which reference was made earlier.

The facilities for adjustment, in addition to allowing a wider range of roll sizes to be used on a given machine, also give great scope to provision for removing residual and axial stresses in a rolled section, thus probably eliminating the need for auxiliary section straightening mechanisms.

It will also be noted that, whereas in previous cold rolling mills it has been necessary to machine accurately the bottom bed plate and the roll pair supports in order to accurately align the centres of the bottom rolls in a mill (when the rolling operation so requires), in the present invention such accuracy is not required, since when such alignment is necessary, it can be achieved by adjustment of each set of bottom roll support stops.

Although, as described, it is preferred to carry each roll supporting block on a pair of supporting pillars, it will be apparent that it is within the scope of the present invention to use a single more massive pillar, of any suitable cross section, to carry the two support blocks for each end of a pair of rolls.

These and other modifications to the embodiments described will be apparent to those skilled in the art as falling within the scope of the present invention.

Claims

1. A roll stand, suitable for inclusion in a multi-stand cold rolling mill, said stand comprising four roll supporting members, characterized in that the relative positions of the four roll supporting members are individually ad adjustable.

2. A roll stand in accordance with claim 1, in which the four roll supporting members are mounted on at least two elongate members which extend such that their principal axes are perpendicular to the roll axes.

3. A roll stand in accordance with claim 2, in which the four roll supporting members are arranged in pairs, each pair being slidably engaged on one of the two elongate members.

4. A roll stand in accordance with claim 2, in which the elongate members have adjustable stops adjacent to their ends, said stops being engageable with said roll supporting members.

5. A roll stand in accordance with claim 1, in which the four roll supporting members are in the form of blocks each having at its' centre portion support means for the end of a roll, and each having at both of its' end portions a hole for engagement with one of the elongate members.

6. A roll stand in accordance with claim 2, in which there are four elongate members arranged in parallel pairs adjacent to the ends of the rolls.

7. A roll stand in accordance with claims 5 and 6 in which at each end of a pair of rolls forming a roll stand there is a pair of roll supporting members which engage upon a pair of elongate members for slidable movement thereon.

8. A roll stand in accordance with claim 4 in which the elongate members are of cylindrical form and have threaded end portions upon which engage lockable threaded means which limit axial movement thereon of the roll support members.

9. A roll stand in accordance with claim 4, in which the elongate members are of cylindrical form and have spacers associated therewith which are engageable with the elongate members at their end portions such as to limit axial movement of the associated roll support means.

10. A cold rolling mill comprising one or more roll stands in accordance with any preceding claim.

11. A roll substantially as described in the accompanying specification.

12. A cold rolling mill substantially as described in the accompanying specification.

13. Any major component knowingly manufactured with the intention of it being used in conjunction with a roll stand in accordance with any preceding claim.