WO1998003285A1

WO1998003285A1 - Continuous casting mould

Info

Publication number: WO1998003285A1
Application number: PCT/GB1997/001945
Authority: WO
Inventors: Ian Cassels; James Nicholas Cooper
Original assignee: Davy Distington Limited
Priority date: 1996-07-23
Filing date: 1997-07-17
Publication date: 1998-01-29
Also published as: GB9615446D0; AU3553897A; GB2315443A

Abstract

A mould for use in the continuous casting of a metal strand, the mould having a fixed part, a movable part (1) which includes means defining the mould passage, and means for oscillating the movable part relative to the fixed part in a direction which is substantially in the direction of casting, wherein the movable part is supported on a plurality of elongate rods (2), and each rod extends substantially in the direction of casting and is associated with a separate fluid operable oscillatable ram (3).

Description

CONTINUOUS CASTING MOULD

This invention relates to a mould for use in the continuous casting of a metal strand and in particular to such a mould having a fixed part, a movable part which includes means defining

the mould passage, and means for oscillating the movable part relative to the fixed part in a direction which is substantially in the direction of casting

It is proposed in accordance with the present invention to support the movable part on a plurality of elongate rods and for each rod to extend substantiallv in the direction of casting and

to be associated with a separate fluid operable oscillatable ram

The rods act as slender struts and bend well within their modulus of elasticity The rods allow lateral misalignment between the oscillatable rams and the movable part of the mould This misalignment can come about during installation or be due to deflection of the support structure

or to thermal expansion

It is desirable for each rod to be connected at its opposite ends to the movable part of the mould and to a ram respectively by way of spring-loaded coupling means which bias the ends of the rod into engagement with the movable part and the ram respectively Fixed stop means are

also provided for limiting the distance of travel of the movable part of the mould in the direction of the length of each rod

Each rod or strut is designed to accommodate up to say 2 5mm of misalignment It is

convenient for each end of the rod to be of part spherical form and to mate with a spherical

seating on the mould or ram

In order that the invention may be more readily understood it will now be described, by

way of example only, with reference to the accompanying drawings in which

Figure 1 is a diagrammatic side elevation of a mould in accordance with the invention, and

Figure 2 is a part-sectional side elevation of a support rod and part of the mould ->

A continuous casting mould for the casting of a metal strand such as a steel billet

comprises a movable part 1 which includes parts which define the mould passage (not shown) The axis of the mould passage is either vertical or if the passage is curved, the axis is substantially vertical The movable part is supported relative to a fixed mould part (not shown) and is oscillated vertically with respect to the fixed part As shown in Figure 1 , the movable part 1 is

mounted on elongate, vertically extending, rods 2 of which two are shown in Figure 1 Each rod is mounted at its upper end to the movable part 1 and is mounted at its lower end on a separate fluid operated ram 3 which is conveniently a hydraulic ram having a fixed cylinder and a vertically movable piston 4 Each ram is operated cychcallv and the forces are transmitted from the rams

through the rods to the movable part I of the mould in order to oscillate the movable part in the direction which is substantially in the direction of casting

Referring to Figure 2, a rod 2 has enlarged end portions 5 and the outer end surface of each end portion is of part-spherical form The upper end of the rod is coupled to the movable

part 1 by way of a quick lelease coupling indicated generally bv reference number 7 Surrounding the upper end 5 of the rod there is a collar 8 which has two slots 9 formed in opposite sides thereof The slots extend at right angles to the axial length of the rod The collar fits withm a

recess in the part 1 and the side wails of the recess which correspond to the slots 9 in the collar

are provided with slots 10 which extend parallel to the slots 9 but are elongated vertically Cylindrical pins 1 project into slots 9 and the corresponding slots 10 in the wall of the recess

The part-spherical end of the rod 5 mates with a spherical seating 19 in the recess and a spring

13 acts between the underside of the enlarged portion 5 and a lower ledge on the collar 8 to bias

the collar downwardly in the recess This biassing action forces the pins to the bottom of the

elongate slots 10

The lower enlarged end portion 5 of the rod 2 has a part spherical portion which bears -> against a seating 1 5 mounted on the top of the piston 4 of the ram 3

Surrounding the piston 4 there is a cylindrical housing 16 and a spring 17 acts between the upper side of the enlarged portion 5 and an upper ledge on the housing

Surrounding a central part of the rod 2 there is an outer tube 18 of a predetermined length

and which is held in fixed relation (by means not shown) A predetermined gap A is formed between the upper end of the tube 18 and the collar 8 and a gap B is formed between the lower end of the tube 18 and the upper ledge on the housing 16

The springs 1 and 17 serve to take up any clearances which may be present between the ram and the rod and the rod and the movable part of the mould

The coupling 7 can quickly be disengaged The cylinders 3 are reduced in pressure to allow the pistons 4 to lower to their lowest position and this causes the mould to be lowered until

the underside of the collar 8 bears against the upper end of the tube 18, i e to close the gap A Further lowering causes the springs 13 to be compressed and the pins 12 move to the centre of the slots 10 thereby allowing the pins to be withdrawn axiallv Similarly to replace the pins, the pistons of the rams are lowered to close gap A and then the pins can be easily entered into the

respective slots When the piston of the ram moves to the operational position the spring is decompressed and the pins locked in position

The springs can absorb some overload

The hydraulic rams have a greater operating stroke than the displacement of the movable

part of the mould There is cushioning at both ends of the working stroke of the piston The spring loaded couplings slacken off when the pistons of the rams are forced into the top and

bottom cushioning This allows the rods to re-set on their spherical ends thus removing any bending which has occurred in the rod

During the normal working stroke the pistons raise and lower the rods, without the gap B being closed, and consequently the movable part 1 of the mould is raised and lowered

The dimension of gaps A and B are different because the hydraulic cushioning within the cylinders is greater on the down stroke

When the cylinders are driven to their top positions to close gap B, the springs are compressed and coupling item 16 can be removed

Claims

1 A mould for use in the continuous casting of a metal strand, the mould having a fixed part, a movable part ( 1 ) which includes means defining the mould passage, and means for oscillating the movable part relative to the fixed part in a direction which is substantially in the

direction of casting, wherein the movable part is supported on a plurality of elongate rods (2), and each rod extends substantially in the direction of casting and is associated with a separate fluid operable oscillatable ram (3 )

2 A mould as in Claim 1 w herein each rod (2) is connected at its opposite ends to the

movable part ( 1 ) of the mould and to a ram ( 3 ) respectively bv wav of spring-loaded coupling means (8, 13 or 16 1 7) which bias the ends (5) of the rod into engagement with the movable part and the ram respectively

3 A mould as in Claim 1 or Claim 2 wherein fixed stop means ( I S) are provided for

limiting the distance of travel of the movable pan ( I ) of the mould in the direction of the length of each rod (2)

4 A mould as in anv one of Claims I to 3 w herein each rod ( 2) is designed to

accommodate up to 2 5 mm of misalignment

5 A mould as in Claim 4, wherein each end (5) of the rod (2) is of part spherical form and mates with a spherical seating ( 1 5 19) on the movable mould part ( 1 ) or ram (3)

6 A mould as in any one of Claims I to 5, whei ein the upper end (5) of each rod (2) is

coupled to the movable part ( I ) of the mould by way of a quick release coupling (7) AMENDED CLAIMS

[received by the International Bureau on 24 November 1997 (24.11.97); original claims 1-6 replaced by amended claims 1-5 (1 page)]

1 A mould for use in the continuous casting of a metal stiand, the mould having a fixed

part, a movable pan (1) which includes means defining the mould passage, and means for oscillating the movable part relative to the fixed part in a direction which is substantially in the

direction of casting, wherein the movable part is supported on a plurality of elongate rods (2), and

each rod extends substantially in the diiection of casting and is associated with a separate fluid

operable oscillatable lam 1 ), chaiactenzed in that each lod (2) is connected at its opposite ends to the movable pan ( I ) of the mould and to a lam (3) lespectivelv bv wav of spring-loaded coupling means (8 13 or 16 I 7) which bias the ends (^) of the lod into engagement with the

movable part and the ram respectively

2 A mould as in Claim 1, wherein fixed stop means ( 18) are provided for limiting the distance of travel of the movable part ( 1) of the mould in the diiection of the length of each rod

(2)

3 A mould as m Claim I ot Claim 2, wheiein each rod (2) is designed to accommodate

up to 25 mm of misalignment

4 A mould as m Claim 3 wheiein each end (>) of the rod (2) is of pan spherical form

and mates witl- a spheucal seating ( 1 \ 1 ) on the mov ble mould pan ( I ) or lam (3)

5 A mould as in anv one of Claims I to 4 wheiein the upper end (5) of each rod (2) is

coupled to the mo able pan ( 1 ) of the mould by wav of a quick telease coupling (7)