US3667271A

US3667271A - Rolling mills

Info

Publication number: US3667271A
Application number: US44489A
Authority: US
Inventors: Stanley Fereday; William Harry Smelt
Original assignee: Davy Loewy Ltd
Current assignee: Davy Loewy Ltd
Priority date: 1969-06-03
Filing date: 1970-06-08
Publication date: 1972-06-06
Anticipated expiration: 1989-06-06
Also published as: GB1241639A; DE2026833A1

Abstract

A cover for a pit comprises two parts which when arranged in side-by-side relation are together of sufficient size and shape to cover the mouth of the pit. One part of the cover is secureable in the mouth of the pit and the second part is supported on inclined surfaces so that the second part can be displaced from the position where it is side-by-side with the first part with their upper surfaces coplanar to a position in which it is beneath the first part. The cover is particularly suitable for covering a pit adjacent a rolling mill. The movable part of the cover may be connected to a sledge in the mill and carrying the rolls so that on withdrawing the rolls the cover is automatically opened.

Description

United States Patent Fereday et al.

[ 1 June 6, 1972 [54] ROLLING MILLS [72] Inventors: Stanley Fereday, Nottingham; William Harry Smelt, Yorkshire, both of England [73] Assignee: Davy and United Engineering Company FOREIGN PATENTS OR APPLICATIONS Primary ExaminerCharles W. Lanham Assistant Examiner-Michael .l. Keenan Att0mey-Henry C. Westin [57] ABSTRACT A cover for a pit comprises two parts which when arranged in side-by-side relation are together of sufficient size and shape [52] US. Cl ..72/238, 49/22] to cover the mouth of the pit. One part of the cover is securea- [51] Int. Cl.... ..B2lb 31/08 ble in the mouth of the pit and the second part is supported on [58] Field of Search ..72/237, 238, 239; 49/33, 234, inclined surfaces so that the second part can be displaced from 49/235 209 210, 221 360 the position where it is side-by-side with the first part with their upper surfaces coplanar to a position in which it is [56] References Cited beneath the first part. The cover is particularly suitable for covering a pit adjacent a rolling mill. The movable part of the UNITED STATES PATENTS cover may be connected to a sledge in the mill and carrying the rolls so that on withdrawing the rolls the cover is automati- 3,45l,244 6/1969 Stover et al ..72/239 Cally opened 3,4l7,509 12/1968 Sherron ...49/209 3,090,264 5/ 1963 Stone et a1. ..72/84 4 Claims, 3 Drawing Figures 4A 2 92) 7b 37 2.9, 22 /Z\ 4 40 11 JO 1] 9/4 Jl l x 4; U 2 31/ 92 27 w .2;

I? Z ta- 2:; .1 m .r'. 1 s v 5 21 Z .L J5 Z6 '20 Great Britain ..49/22 I PATENTEDJUM 61972 venlo STANLEY FEREDAY AM HARRY SMELT HENRY C WESUN Q RN 0 mm N Mm m 5 Q mm mm mm QM an Aw QM Q Ev Q N m K ax i PKVM... NR

D III" II In! 1/ Z M S Attorn y j ROLLING MILLS This invention relates to a cover for a pit. Although the word pit" is usually understood to mean a hole or a trench in the ground, it is intended that in this specification the word pit should be contrued to include a sunken area beneath, or a hole in, a floor of a building. A particular, but not sole, application of the invention is to a cover for a pit in the floor of a workshop in which metals are rolled, the pit being on the roll change side of a rolling mill. When the mill rolls are periodically removed from the mill they are withdrawn into the pit, but when the mill is in use the pit has to be covered.

In U.S. Pat. No. 3,204,443 a pit at the roll change side of a rolling mill has a two-part cover with the parts arranged sideby-side. When the pit is to be exposed, the part of the cover adjacent the mill is slid horizontally to a position underneath the other part of the cover. This arrangement however suffers from the serious disadvantage that when both parts are positioned side-by-side the upper surfaces of the two parts are not co-planar and there is a step between the levels of the two parts. Serious accidents can occur if a mill operator trips on the step between the two parts of the pit cover. This is particularly likely to happen if a cobble occurs when the mill is in use and it is necessary for the mill operators to run away from the vicinity of the mill to positions of safety.

It is an object of the present invention to provide a two-part pit cover which can readily be moved to open the pit and which, when the pit is covered, provides a flat surface without a step between the two parts.

According to the present invention a cover for a pit (as hereinbefore defined) comprises first and second parts which when arranged in side-by-side relation are together of sufficient size and shape to close the mouth of the pit, the first part of the cover being fixedly securable in the mouth of the pit and the second part being supported on surfaces which include inclined portions, the surfaces permitting the second part of the cover to be displaceable between a first position in which the parts are in side-by-side relation with their upper surfaces co-planar and a second position in which the second part is beneath the first.

Preferably the surfaces which include inclined portions are provided by tracks positionable in the pit beneath the cover. Wheels or rollers are conveniently provided on the second part of the cover with the wheels or rollers associated with the tracks.

Although the second part of the pit cover could be moved manually between the first and second positions, it is preferable for the part of the cover to be moved by means of a fluid operated piston and cylinder device coupled thereto and positionable in the pit beneath the cover.

In order that the invention may be more readily understood, it will now be described, by way of example only with reference to the drawings filed with the provisional specification, in which:

FIG. 1 is a sectional side elevation of a cover associated with a pit on the floor at the roll-change side of a rolling mill,

FIG. 2 is a section on the line II-II of FIG. 1,

FIG. 3 is an enlarged view in section of a portion of the cover illustrated in FIG. 1.

In FIG. 1, a rolling mill stand is indicated by reference numeral 12. The stand comprises a pair of identical spaced-apart housings, one of which is shown at 13, and each housing defines a window 14. The mill rolls (not shown) are supported at their ends in bearing chock assemblies which are positioned in the housing windows. During roll changing the chocks are supported on a sledge which is positioned in the bottom of the housings and extends between the windows.

An elongate pit is provided in the mill foundations 21, on the roll change side. The pit 20 extends normal to the pass-line of the mill. The pit 20 is covered at mill floor level, represented at 22 in the drawing, by a cover having a first fixed floor plate 23 and a second movable floor plate 24. The fixed plate 23 is supported at its edges on the foundations 21 in the mouth of the pit in a position remote from the mill stand 12.

In the bottom of the pit 20 a sliding bed 25 is provided which extends along approximately half the length of the pit from the roll stand end and at a height level with the bottom of the housing window 14. A double-acting fluid operated piston and cylinder unit 26 is supported in the pit 20 below the fixed plate 23. A piston rod 27 of the unit 26 is coupled by way of a coupling block 28 to the sledge 15. By operating the unit 26 the sledge 15 is movable relative to the mill stand 12 along the sliding bed 25.

Two pairs of spaced-apart flanged

wheels

30, 31 are mounted on brackets attached to the underside of the movable floor plate 24. Each pair of

wheels

30, 31 is supported on a respective pair of tracks 32, 33. The ends of the rails 32, 33 nearest the mill stand 12 are inclined upwards to form ramps 34, 35 which terminate in flat tops. The height of the ramps 34, 35 is such that when the

wheels

30, 31 are on the flat tops thereof the upper surface of the movable floor plate 24 is level with that of the fixed floor plate 23. The angle of inclination of the ramps 34, 35 is such that when the movable plate 24 is moved to the right in FIG 1, it moves under the fixed floor plate 23 to a position shown in chain lines. To facilitate this operation a portion 36 of the fixed floor plate 23 which is adjacent the plate 24 is hinged at 37. A roller 38 is provided on the underside of the hinged portion 36. When the movable plate 24 is moved to the right in FIG. 1, the roller 38 engages a cam surface 39 provided on the plate 24 which causes the portion 36 to swing upwards clear of the plate 24.

The movable floor plate 24 follows simultaneously the movements of the sledge 15 by means of a link 40 pivotally attached to brackets 41, 42 secured to the block 28 and the plate 24 respectively.

FIG. 2 shows the cross-sectional layout of the various parts of the described apparatus on the line II-II of FIG. 1. The central portion of the bottom of the pit 20 is occupied by the sliding bed 25 so that the sledge 15 can be withdrawn from the window 14 without fouling any fittings. The rails 32, 33 and the ramps 34, 35 are supported along the bottom edges of the pit 20. It is to be noted that the pair of rails 32 and their associated ramps 34 are located inboard of the other pair of rails 33 and the ramps 35. This is because the wheels 30 have to roll pass the ramps 35 when the movable plate 24 is displaced to the right in FIG. 1 and if the wheels of each

pair

30, 31 were spaced equally apart then this would not be possible.

When changing the back-up rolls in the mill stand 12, the work rolls (not shown) are first removed and then either the lower back-up roll or the upper back-up roll (not shown) supported on the chocks 16 of the lower back-up roll so as to form a unit, is removed from the mill stand 12 by actuating the piston and cylinder unit 26. Simultaneously the movable floor plate 24 is pulled down the ramps 34, 35 and along the rails 32, 33 until the plate 24 is in the position shown in the chain lines in FIG. 1. By this time the sledge 15 with its load is positioned in the pit 20 below the opening left by the plate 24. A crane then removes the old roll or rolls with their chocks from the sledge and replaces them on the sledge with a new roll or rolls. The sledge 15 and the movable plate 24 are returned to the position shown in full lines in FIG. 1.

If desired the pairs of

wheels

30, 31 may be replaced by roller or skids.

In accordance with the provisions of the patent statutes, we have explained the principles and operation of our invention and have illustrated and described what we consider to represent the best embodiment thereof.

We claim:

1. A cover for a pit, the cover comprising first and second parts which when arranged in side-by-side relation are together of sufiicient size and shape to close the mouth of the pit, the first part of the cover being fixedly securable in the mouth of the pit and the edge of the first part which is adjacent the second part when the two parts are in side-by-side relation being defined by a member separate from the remainder of the first part and hinged thereto, said second part having wheels provided on the underside at the opposite ends thereof which are adjacent and away from the first part respectively when the two parts are in side-by-side relation, said wheels at one end of the second part being associated with first track means which include inclined portions and which are positionable in the pit beneath the cover and the wheels at the other end of the second part being associated with further track means which includeinclined portions and which are positionable in the pit laterally with respect to said first track means, said inclined portions of the track means permitting the second part of the cover to be displaceable between a first position in which the parts are in side-by-side relation with their upper surfaces coplanar and a second position in which the second part is beneath the first part, cooperating means carried by said hinged member of the first part of the cover and said second part of the cover which cause said hinged member to pivot away from the second part when the second part is displaced from the first position to the second position and a fluid operated piston-cylinder device operatively coupled to said second part and locatable in said pit and which serves to displace said second part between the first and second positions.

2. A pit cover as claimed in claim 1 in which said-CO-Operating means comprise a roller on said hinged part and a cam surface on the second part.

3. A pit cover as claimed in claim 1 in which the cover is associated with a pit at the roll change side of a rolling mill, the cover is positionable at floor level with the second part of the cover adjacent the rolling mill. 7

4. Apit cover as claimed in claim 1 in which a sledge is positioned in the mill to support the rolls during roll changing and the sledge is coupled to said piston and cylinder device, whereby displacement of the second part of the cover to the second position causes the sledge to be displaced into the pit.

Claims

1. A cover for a pit, the cover comprising first and second parts which when arranged in side-by-side relation are together of sufficient size and shape to close the mouth of the pit, the first part of the cover being fixedly securable in the mouth of the pit and the edge of the first part which is adjacent the second part when the two parts are in side-by-side relation being defined by a member separate from the remainder of the first part and hinged thereto, said second part having wheels provided on the underside at the opposite ends thereof which are adjacent and away from the first part respectively when the two parts are in side-by-side relation, said wheels at one end of the second part being associated with first track means which include inclined portions and which are positionable in the pit beneath the cover and the wheels at the other end of the second part being associated with further track means which include inclined portions and which are positionable in the pit laterally with respect to said first track means, said inclined portions of the track means permitting the second part of the cover to be displaceable between a first position in which the parts are in side-by-side relation with their upper surfaces coplanar and a second position in which the second part is beneath the first part, cooperating means carried by said hinged member of the first part of the cover and said second part of the cover which cause said hinged member to pivot away from the second part when the second part is displaced from the first position to the second position and a fluid operated piston-cylinder device operatively coupled to said second part and locatable in said pit and which serves to displace said second part between the first and second positions.

2. A pit cover as claimed in claim 1 in which said co-operating means comprise a roller on said hinged part and a cam surface on the second part.

3. A pit cover as claimed in claim 1 in which the cover is associated with a pit at the roll change side of a rolling mill, the cover is positionable at floor level with the second part of the cover adjacent the rolling mill.

4. A pit cover as claimed in claim 1 in which a sledge is positioned in the mill to support the rolls during roll changing and the sledge is coupled to said piston and cylinder device, whereby displacement of the second part of the cover to the second position causes the sledge to be displaced into the pit.