EP4035796A1

EP4035796A1 - Mould for vertically casting aluminium ingots

Info

Publication number: EP4035796A1
Application number: EP20869592.4A
Authority: EP
Inventors: Viktor Khrist'yanovich MANN; Aleksandr Yur'evich SIDOROV; Oleg Viktorovich VERBITSKIJ; Aleksandr Gennad'evich PELEVIN; Sergej Viktorovich SOLDATOV; Vyacheslav Gennad'evich VASILENKO
Original assignee: Rusal Engineering and Technological Center LLC
Current assignee: Rusal Engineering and Technological Center LLC
Priority date: 2019-09-24
Filing date: 2020-09-18
Publication date: 2022-08-03
Also published as: CN114450101A; CA3154702A1; WO2021061017A1; RU2742553C1; EP4035796A4

Abstract

A mould for vertical casting in the production of aluminium ingots comprises a body having an upper flange and a lower flange. Moreover, the mould body is in the form of a prefabricated structure comprising a casting frame and at least one water supply unit fastened to the frame. In addition, the mould can comprise at least one of the following systems: a system for controlling the cooling of the mould and ingots; a system for controlling the lubrication of the ingots, including supplying and retaining lubricant; and a system for positioning the mould on the casting table relative to the bottom plate. The invention makes it possible to prolong the service life of a mould, with the overall effect being a decrease in the time spent preparing for the casting and an increase in the productivity of the mould.

Description

Field of the invention

The invention relates to the field of foundry production and can be used for vertical casting of metal ingots, in particular, ingots made of aluminium and its alloys.

Background of the invention

For the production of aluminium ingots, the method of vertical semi-continuous casting with direct cooling of ingots is widely used. The essence of the method consists in the continuous supply of liquid metal to a special water-cooled crystallising mould, with a movable bottom, the role of which is performed by a movable bottom plate moving in a vertical direction. Casting machines for semi-continuous casting of ingots consist of two main components: a crystallising mould and a bottom plate movement mechanism. The crystallising mould body is usually made of copper or a solid aluminium alloy. The speed of lowering the bottom plate is selected so that the ingot does not freeze over the entire cross-section, but a surface crust is formed. Further crystallising of the ingot occurs when its surface is cooled with water. Casting stops when the ingot reaches the specified length, and then the process is repeated again. For example, see Odintsov M.V. Analysis of the Aluminium Casting Process in a Crystallising Mould with a Movable Bottom. // Engineering Sciences: Problems and Prospects: Materials of the International Scientific Conference (St. Petersburg, March 2011). - St. Petersburg: Renome, 2011. - pp. 126-129.
To explain the equipment used for the implementation of vertical semi-continuous casting with direct cooling of ingots, the attached drawings show typical configurations of the equipment, discussed in detail below.

Fig. 1 - diagram of equipment for vertical casting with direct cooling of the ingot;
Figs. 2 and 3 - design option of the vertical casting machine;
Fig. 4 - general view of the casting bottom plate;
Figs. 5 and 6 - general view of the crystallising mould;
Figs. 7 and 8 - cross section of the crystallising mould body;
Fig. 9 - segment of the upper flange longitudinal section;
Fig. 10 - cross-section of the crystallising mould body with the upper flange installed;
Fig. 11 - cross section of the crystallising mould body with the lower flange and alignment system cylinder installed;
Fig. 12 - bottom view of the crystallising mould with the bottom plate during positioning.

Fig. 1 shows a typical configuration of equipment for vertical casting with direct cooling of the ingot. Liquid metal 1 is fed through a sleeve 2 into a water-cooled crystallising mould 3 (direction A) with a movable bottom, the role of which is performed by a bottom plate 4 moving in the vertical direction B on a platform 5 with a drive. Cooling water is supplied to the internal water chamber 6 of the crystallising mould to maintain the necessary temperature of the walls that come into contact with liquid metal 1. The cooling intensity can be changed by regulating the water flow. Due to this primary cooling, the initial solidified shell of an ingot 7 is formed near the wall of the crystallising mould 3. The water chamber 6 of the crystallising mould 3 is provided with a set of holes for water. When passing through the holes in the chambers 6, water jets 8 are formed, washing the directly formed surface of the ingot 7, and thereby provide further crystallising. The platform 5 with the bottom plate 4 installed on it is lowered at a given speed, the hardened metal exits the cavity of the crystallising mould 3, forming an ingot. Casting is stopped when the ingot reaches the required length. The finished ingot is removed from the platform and the casting of a new ingot continues.
Figs. 2 and 3 show one of the many design options of a vertical casting machine that allows four ingots to be cast simultaneously. The platform 5 with a drive is installed in a casting pit 9 below the floor level of the casthouse. A transition plate 10 with the bottom plates 4 is installed on the platform 5. The crystallising moulds 3 are installed on a table 11 of the casting machine and are connected to the water supply system through hoses 13 with detachable connections. To remove the obtained ingots from the platform after the casting is completed, the casting machine has a drive 12 that allows to lift the table 11 from the horizontal position A to the vertical position B.
Fig. 4 shows a general view of one of the many design options for the bottom plate. The bottom plate is a mechanically processed metal mould with a flat or hemispherical bottom and edge contours that repeat the profile of the working cavity of the crystallising mould. The dimensions of the bottom plate allow to bring it to a certain distance into the working cavity of the crystallising mould. Thus, the crystallising mould and the bottom plate form a single casting mould.
Modern crystallising moulds are equipped with auxiliary systems that allow to improve the quality of ingots, reduce the time of preparatory operations.
These systems are:

a control system for cooling ingots, which allows to change the cooling intensity, thereby affecting the structure of the metal and the amount of its shrinkage;
a system of feeding and retaining lubricant in the crystallising mould, distributing lubricant over the working surface of the crystallising mould, in order to obtain a smooth surface of the ingot, and preventing the leakage of lubricant from the crystallising mould when lifting the casting table to a vertical position;
the crystallising mould positioning system on the casting table relative to the bottom plate, which allows to automatically align the working cavity of the mould with the contours of the edges of the bottom plate before casting, thereby reducing the preparation time for casting.

Figs. 5 and 6 show a general view of one of the many design options of the crystallising mould. The crystallising mould contains a body 14, the walls of which form a working cavity A, an upper flange 15, side walls 17, a lower flange 16 with pneumatic cylinders 18 mounted on it for positioning the mould on the casting table relative to the bottom plate. A bottom plate is inserted into the working cavity before casting, and liquid metal is fed during the casting process.
Figs. 7 and 8 show a view of cross section of the crystallising mould body. A body 14 together with side walls 17 form two internal cooling chambers. A primary cooling chamber 19 and a secondary cooling chamber 20 are separated by a partition containing a connecting channel 21. A water flow control valve 22 is installed on the body. The water supply to the primary cooling chamber 19 is carried out through a supply channel 23. The water supply to the secondary cooling chamber 20 is carried out from the primary chamber 19 through the connecting channel 21. Several outlet channels 24 are coming out from each chamber 19 and 20, designed to supply water to the surface of the ingot being formed.
During the casting process, a circulation pump operates, ensuring the presence of a constant pressure and the flow of water into the crystallising mould through the supply channels 23. At the initial stage of casting, pressurised air is fed through the pipelines of the water flow control system into a valve 22. A shut-off element 25 of the valve extends and closes the connecting channel 21, preventing water from entering the secondary cooling chamber 20. Water passing through the supply channel 23 fills the cavity of the primary cooling chamber 19 and from there is supplied on the ingot surface through the outlet channels 24. The use of only the primary cooling chamber and one row of outlet channels at the initial stage of casting reduces the intensity of cooling of the ingot. When switching to the casting operating mode, the air pressure inside the valve 22 is removed. The shut-off element 25 of the valve opens the connecting channel 21, allowing the flow of water to pass into the secondary chamber 20. From the secondary cooling chamber 20, water flows through the outlet channels 24 to the surface of the ingot. The intensity of cooling of the ingot increases.
The upper flange 15 of the crystallising mould contains a lubricant supply system. Fig. 9 shows a view of the segment of the upper flange longitudinal section. Fig. 10 shows a cross-section view of the crystallising mould body with the upper flange installed. The upper flange 15 contains a groove 26 connected to an inlet fitting 27 and outlet holes 28. The outlet holes 28 are located on the surface of the inner contour of the flange with a certain pitch, and ensure an even distribution of lubricant over the working surface of the crystallising mould body 14. During the casting process, a discharge pump ensures the presence of excess pressure and the flow of lubricant from the feed tank to the lubrication supply device through the inlet fitting 27. The lubricant fills the groove 26 and flows out through the outlet holes 28, lubricating the working surface of the crystallising mould body 14. Also, the outlet holes can contain shut-off elements retaining lubricant inside the flange when lifting the casting machine table to a vertical position at the end of the casting process.
The lower flange 16 of the mould contains a mould positioning system relative to the bottom plate. Fig. 11 shows a cross-section view of the crystallising mould body with the lower flange 16 and the cylinder 18 of the alignment system installed. Fig. 12 shows a bottom view of the mould with the bottom plate at the time of positioning (the cylinder pistons are extended). Before casting, the bottom plate 4 attached to the movable platform of the casting machine, is brought to the working cavity of the crystallising mould body 14. At the command from the control panel, compressed air enters the working cavity of the cylinders 18 through the groove 29 in the lower flange 16. Under the influence of air pressure, pistons 30 are pushed out of the cylinders 18 and, resting against the side wall of the bottom plate 4, move the crystallising mould, aligning its working cavity with respect to the bottom plate. After positioning, the compressed air supply is turned off, the piston returns to its initial position under the influence of the spring force. The crystallising moulds are fixed in this position by fastening them to the table of the casting machine.
From the state of the art, many design options of the above-mentioned crystallising mould systems are known.
For example, the international application WO 9523044 (IPC B22D11/049, publication date: August 31, 1995 ) discloses the design of a crystallising mould containing a body, an upper cover and a lower cover. The mould body together with the covers form cooling chambers - one primary cooling chamber and four secondary cooling chambers. Each chamber contains a row of outlet channels for supplying water to the surface of the ingot. The mould body is provided with connecting channels between the chambers. On the lower cover, water flow control valves are installed, made in the form of pneumatic cylinders and able to block the connecting channels with their shut-off elements, thereby changing the cooling intensity of the ingot.
The international application WO 2012126108 (IPC B22D11/049, publication date: September 27, 2012 ) discloses the design of a crystallising mould containing a body, an upper cover and a lower cover. The body together with the covers form two cooling chambers. Each chamber contains a row of outlet channels for supplying water to the surface of the ingot. The mould body is provided with connecting channels between the chambers. The water flow control valves are built into the body, made in the form of a bladder made of elastic material stretched under gas pressure. The valves are able to block the connecting channels with their shut-off elements, thereby changing the cooling intensity of the ingot.
The international application WO 2004035246 (IPC B22D11/07, publication date: April 29, 2004 ) discloses the design of the mould lubrication supply system, containing a lubrication pipeline that provides the flow of lubricant and the distribution of lubricant around the mould cavity, and a lubrication pipeline plug that prevents spontaneous leakage of lubricant through the outlet holes of the pipeline after the end of the ingot casting process. The plug is placed inside the pipeline, or in the lubrication outlet holes or next to the lubrication outlet holes. The plug is made in the form of an elastic bladder, or a porous diaphragm, or a rotary valve, or a partition with capillary holes.
The international application WO 9409930 (IPC B22D11/049, publication date: November 4, 1992 ) discloses the design of a crystallising mould containing a body and an upper cover. The mould body together with the cover form a cooling chamber. The upper cover contains the channels of the mould lubricant supply system. Eight pneumatic cylinders of the mould positioning system in relation to the bottom plate are attached to the lower side of the mould body. The cylinders are installed along the perimeter of the working cavity of the mould - two on each face. Compressed air is supplied to the cylinders through the grooves made in the mould body. When compressed air is supplied, the cylinder rods are extended and the mould is aligned in relation to the bottom plate.
Also known is the crystallising mould according to RF patent No 2281183 (IPC B22D 11/04, 11/07, publication date: August 10, 2006 ), which has two isolated chambers: a cooling chamber and a pre-chamber with inlet and outlet channels. For the supply of liquid lubricant to the working surface of the crystallising mould, a groove is made in the upper part of the mould body. The uniform flow of coolant is achieved thanks to the vertical and horizontal partitions of the chambers. In the cooling chamber, the lower horizontal partition is installed above the inlet channel, and a gap is made in the middle in the upper horizontal partition. In the pre-chamber, the horizontal partition is installed with a gap relative to the side cover of the mould body, and the vertical partition is installed with a gap relative to the upper border of the pre-chamber. An additional inlet channel is made in the bottom of the pre-chamber. The invention makes it possible to increase the casting speed and productivity of casting machines while ensuring high surface quality of the cast ingots by regulating the cooling intensity of the cast ingots.
The patent RU 2659548 (IPC B22D 11/04. 11/07, publication date: July 2, 2018 ), obtained by RUSAL, discloses a crystallising mould for vertical semi-continuous casting of aluminium ingots, containing a body, a cover located in the upper part of the body and a device for supplying lubricant to the working surface of the mould with an inlet pipe and outlet holes. The lubricant supply device is made in the form of two grooves inside the mould cover, one of which is made from the side of the outer contour of the cover, and the other - from the side of the inner contour of the cover connected by connecting channels, and the groove from the side of the outer contour of the cover is connected to the lubricant supply inlet pipe, and the groove from the side of the inner contour of the cover is connected to the outlet holes located around the perimeter of the cover. At the same time, hydraulic check valves are installed in the connecting channels able to open the connecting channels under pressure and to supply lubricant from one groove to another, and then through the outlet holes to the working surface of the mould body. The invention makes it possible to reduce the time of filling the feed device with lubricant, to ensure the simultaneous start of the supply of lubricant from the outlet holes around the entire perimeter of the cover, to retain lubricant in the groove made from the outer contour of the cover after the end of the ingot casting process, to simplify the process of cleaning the outlet holes. The used system of feeding and retaining lubricant when lifting the casting table does not prevent spontaneous draining of lubricant residues from the groove made on the side of the inner contour of the cover. Spontaneous draining of lubricant from the crystallising mould and formation of oil stains on the floor of the casthouse is unacceptable according to safety requirements.
The technical solution of the crystallising mould according to the international application WO 9409930 is accepted as a prototype of the present invention.
All of the above analogues, as well as the prototype, require the elimination of shortcomings and further improvements in both the design and auxiliary systems of the crystallising mould to improve the quality of the ingot. For example, according to the international applications WO 9523044 and WO 2012126108 , channels for water supply, connecting channels between chambers, water flow control valves, channels for compressed air supply are made in the mould body. In addition, the installation of water flow control valves inside the mould body, made in the form of pneumatic cylinders, leads to a further complication of the design, since it requires making additional channels in the mould body for removing air from under the cylinder piston. As experts in this field of technology can easily understand, such a mould body design requires significant technical means and costs during manufacture. The negative point is that the service life of the mould body is limited, due to gradual wear and deformation of the surfaces of the working cavity of the mould during casting, electrochemical corrosion of the water flow control valves seats. In the patent RU 2659548 , the proposed system of feeding and retaining lubricant when lifting the casting table does not prevent spontaneous draining of lubricant residues from the groove made on the side of the inner contour of the cover. Spontaneous draining of lubricant from the crystallising mould and formation of oil stains on the floor of the casthouse is unacceptable according to safety requirements. The disadvantages of the design of the lubricant feeding and retaining system disclosed in the application WO 2004035246 are: the complexity of the practical implementation of the proposed options; the need to supply compressed air to stretch the elastic bladder; clogging of the pores of the diaphragm or capillary holes of the partition.
Also, the design disadvantages of the equipment are inherent in other analogues and the prototype, in connection with which the main task of the present invention is to develop an improved design of the ingot cooling and water flow control system, which allows to extend the service life of the crystallising mould parts that are difficult to manufacture, as well as to improve the design of the lubricant feeding and retaining system, containing a device with the functions of dosing the amount of supplied lubricant and its retention when lifting the casting table.
As can be seen from the application WO 9409930 , all pneumatic cylinders installed along the perimeter of the working cavity of the crystallising mould are activated simultaneously in the positioning system - two on each face. In practice, the simultaneous actuation of the cylinders on the wide and narrow sides of the working cavity of the mould can lead to an unsatisfactory positioning result, due to the wedging of the mould with the extended cylinder rods. In view of the above-said, a positioning system design with an alternative pneumatic cylinder triggering algorithm needs to be developed.

Disclosure of the invention

The general technical task of the proposed invention is to extend the service life of the crystallising mould, and to eliminate contamination of cast ingots and workplaces around the casting machine with lubricant, with the final effect expressed in reducing the time of preparing for casting and increasing the productivity of the crystallising mould.
To implement this task, it is necessary to improve the design of the crystallising mould, to develop an auxiliary control system for cooling ingots, which allows to extend the service life of the mould parts that are difficult to manufacture, to develop a design of a lubrication control system containing a device with the functions of dosing the amount of supplied lubricant and retaining it when lifting the casting table, as well as to develop a design of a positioning system with an alternative pneumatic cylinder triggering algorithm.
At the same time, it is important to allow both simultaneous and separate use of these auxiliary systems in the mould, as well as their use in combination.
The implementation of the assigned task and the achievement of the technical result is ensured by the fact that the mould body, according to the proposed invention, is made in the form of a prefabricated composite structure containing a casting frame and at least one and preferably two water supply units attached to the frame by bolted connections. The water supply unit contains water supply fittings, connecting channels between water chambers. The material of the casting frame is aluminium alloy. In a particular version, water supply units can be made of corrosion-resistant materials, such as stainless steel, titanium alloy. This design will ensure a longer service life of the units, since only the casting frame comes into contact with the molten metal during casting of ingots.
Additionally, the crystallising mould can contain an optional cooling system, in which the water supply units additionally contain water flow control valves and channels for supplying compressed air to the valves. The water flow control valve is made in the form of a one-way pneumatic cylinder with a return spring and air exhaust from the under-piston space through the piston rod. This design does not require the arrangement of additional channels for air in the water supply unit. Also, to exclude the impact of electrochemical corrosion on the unit, the mould body and shut-off element of the valve can be provided with an anti-corrosion coating made of polymer materials, such as polypropylene, polyurethane, fluoropolymer. The anti-corrosion coating of the valve body can be made in the form of a shell, while the anti-corrosion coating of the valve shut-off element can be made in the form of a cover plate.
An additional element of the crystallising mould is optionally a lubricant feeding and retaining system located in the upper flange of the mould body, which contains nozzles with shut-off elements able to open by the action of lubricant pressure. The proposed design of the lubrication control system allows for the possibility of dosing the amount of supplied lubricant by installing nozzles with different diameters of the outlet holes in order to exclude spontaneous draining of lubricant when lifting the casting machine table into a vertical position by locking the outlet holes, for example, with elastic shut-off elements of the nozzles.
An optional system for positioning the mould on the casting table relative to the bottom plate has also been developed, pneumatic blocks containing pneumatic cylinders with time-delay valves have been installed. The proposed design of the mould positioning system on the casting table relative to the mould bottom plate allows to change the algorithm (sequence) of actuation of pneumatic cylinders, excluding wedging of the mould with extended cylinder rods.

List of drawings

The invention is explained by the drawings, which show:

Fig. 13 - crystallising mould body of a prefabricated composite design.
Fig. 14 - side view of the water supply unit.
Fig. 15 - cross section of the casting frame.
Fig. 16 - water flow control valve.
Fig. 17 - segment of the upper flange with nozzles installed.
Figs. 18a and 18b - design of the nozzle with a shut-off element in the form of an O-ring.
Figs. 19a and 19b - design of the nozzle with a shut-off element in the form of a T-shaped (mushroom) valve.
Fig. 20a - pneumatic diagram of the positioning system unit.
Figs. 20b and 20c - operating diagram of the pneumatic unit.
Fig. 21 - crystallising mould bottom view.

Detailed description of the invention

The design of the mould body is explained in Figs. 13, 14 and 15, and contains the following structural elements:

31 - casting frame;
32 - water supply unit;
17 - side wall;
22 - water flow control valve.

Fig. 13 shows the main structural elements of the prefabricated crystallising mould body.
Fig. 14 shows a side view of the water supply unit 32 complete with the water flow control valves 22.
Fig. 15 shows a cross-section of the casting frame 31 complete with the water supply unit 32 and water flow control valves 22 installed.
The design of the water supply unit with one or more valves can be simplified by using (a) water flow control valve(s) made in the form of a one-way pneumatic cylinder with a return spring and air exhaust from the under-piston space through the piston rod. This design does not require the arrangement of additional channels for air in the water supply unit.
Also, to exclude the impact of electrochemical corrosion on the water supply unit, the body and the shut-off element of the valve can be provided with an anti-corrosion coating made of polymer materials such as polypropylene, polyurethane, PTFE. The anti-corrosion coating of the valve body can be made in the form of a shell, while the anti-corrosion coating of the valve shut-off element can be made in the form of a cover plate.
Fig. 16 discloses the proposed design of the water flow control valve. The valve includes the following structural elements:

33 - mould body;
34 - piston rod;
25 - shut-off element;
35 - cover;
36 - lock ring;
37 - spring;
38 - air channel in the mould body;
39 - air channel in the rod;
40 - polymer shell;
41 - polymer cover plate.

The operation of the valve is described below.
To reduce the intensity of cooling of the ingot during the casting process, by command (for example, from the control panel), pressurised air is supplied through the channel 38 of the mould body 33 into the space between the piston rod 34 and the cover 35. Under the influence of pressure, the piston rod 34 moves upwards, compressing the spring 37. The air from the under-piston space is removed from the valve through a channel 39 made in the piston rod 34. The extended shut-off element 25 blocks the channel between the water chambers.
To increase the cooling intensity of the ingot, the air pressure in the system is removed by command (for example, from the control panel). By the action of the spring 37 pressure, the piston rod 34 returns to its original position. The air is removed from the space between the piston rod 34 and the cover 35 through a channel 38 and enters the under-piston space through the channel 39, respectively. The shut-off element 25 opens the channel between the water chambers.
To exclude the impact of electrochemical corrosion on the valve block, the mould body 33 is provided with an anti-corrosion coating in the form of a polymer shell 40, the shut-ff element 25 has an anti-corrosion coating in the form of a polymer cover plate 41.
Additionally, according to the proposed invention, an optional lubricant feeding and retaining system is provided located in the upper flange of the mould body, which contains nozzles with shut-off elements able to open by the action of lubricant pressure. Fig. 17 shows the segment of the upper flange of the crystallising mould body 15 with nozzles 42 installed.
The shut-off element of the nozzle can be made in the form of an O-ring or a T-shaped valve.
The design and principle of operation of the nozzle with a shut-off element in the form of an O-ring is explained in Figs. 18a and 18b where:

31 - casting frame;
15 - crystallising mould body upper flange;
26 - groove;
28 - upper flange outlet hole;
42 - nozzle;
43 - nozzle shut-off element;
44 - nozzle outlet hole.

The nozzle 42 contains a radial groove in which the outlet hole 44 is located. The groove is sealed with a shut-off element 43 in the form of an O-ring. An O-ring made of an elastic material, for example, rubber or elastic plastic, ensures clearing of the outlet hole at a preset pressure in the lubricant supply system, which is higher than the ambient pressure. As the lubrication pressure increases, at a certain moment the O-ring loses contact with the edges of the groove, at least on some part of the edges of the groove, ensuring that the lubricant exits to the outside until the pressure decreases to such an extent that the elasticity of the O-ring will prevail and the ring will again rest against the edges of the groove along its entire periphery. In a particular version, the lubricant exit to the outside is provided at a pressure in the system of at least 0.2-1.0 bar, and the diameter of the outlet hole of the nozzle is of 0.4-1.2 mm, preferably of 0.6-1.0 mm.
The design and principle of operation of the nozzle with a shut-off element in the form of a T-shaped valve is explained in Figs. 19a and 19b where:

The nozzle 42 contains an outlet hole 44, which is sealed by a shut-off element 43, in the form of a T-shaped valve, the leg of which is provided with a conical hook, made of elastic material, for example, rubber or elastic plastic, while the sealing surface of the valve is the back surface of the cap, which is made flat and ensures opening of the outlet hole at a preset pressure in the lubricant supply system, which is higher than the ambient pressure. When the lubrication pressure increases, at a certain moment the surface of the valve cap loses contact with the surface of the nozzle 42, ensuring that the lubricant exits to the outside until the pressure decreases to such an extent that the elasticity of the valve prevails and the surface of the valve cap will again lock the outlet hole. In a particular version, the lubricant exit to the outside is provided at a pressure in the system of at least 0.2-1.0 bar, and the diameter of the outlet hole of the nozzle is of 0.4-1.2 mm, preferably of 0.6-1.0 mm.
The proposed design of the lubrication control system allows to dose the amount of supplied lubricant by installing nozzles with different diameters of outlet holes, to exclude spontaneous draining of lubricant when lifting the casting machine table into a vertical position by locking the outlet holes with elastic shut-off elements of the nozzles.
Also, according to the proposed invention, an optional system for positioning the mould on the casting table relative to the bottom plate is provided, for which purpose pneumatic units containing pneumatic cylinders with time-delay valves have been installed.
Fig. 20a shows the pneumatic circuit of the unit. The principle of operation of the pneumatic unit is explained in Figs. 20b and 20c, where:

45 - pneumatic reservoir;
46 - cylinder;
47 - throttle;
48 - spool-type pilot;
a - control channel;
b - feeding channel;
c - spool-type pilot exhaust channel;
d - spool-type pilot outlet channel;
e - cylinder exhaust channel.

The time-delay valve consists of a spool-type pilot 48, a throttle 47 with a check valve and a small pneumatic reservoir 45. Compressed air is fed to the valve by the channel b. A pneumatic control signal is applied to the input of the control channel a and begins to fill the reservoir 45 through an adjustable throttle 47. The setting of the throttle 47 affects the amount of air flow, and consequently the time for which the pressure in the reservoir 45 will increase. When pressure in the reservoir 45 reaches the preset pressure value, the shut-off device of the spool-type pilot 48 moves (see Fig. 20b). The shut-off device blocks the passage from the outlet channel of the spool-type pilot d to the exhaust channel of the spool-type pilot c, and then the passage from the feeding channel b to the outlet channel of the spool-type pilot d is opened. Compressed air is supplied to the cylinder 46. The time required to fill the pneumatic reservoirs with compressed air to the preset pressure value is the setting time of this device.
To switch the time-delay valve to the initial position, the signal should be removed from the input of the control channel a. The air from the pneumatic reservoir 45 will be quickly discharged to the atmosphere through the check valve, and the spool-type pilot 48 will return to its original position under the action of the spring, blocking the feeding channel b and connecting the outlet channel of the spool-type pilot d to the exhaust channel of the spool-type pilot c. The piston of the cylinder 46 will return to its original position by the action of the spring force (see Fig. 20c).
Fig. 21 shows a bottom view of the crystallising mould, where pneumatic units 49 are installed on the lower flange 16 in the amount of six pieces (two on the wide faces of the working cavity of the crystallising mould, and one on the narrow faces).
An important difference of the proposed solution is the use of a time-delay valve allowing to change the algorithm (sequence) of cylinder actuation, i.e., to further control the process and adjust the system design to improve its performance and consequently to improve the quality of the final product.
In a particular version, the time-delay valves provide a time-delay range from 0 to 30 seconds. For example, by changing the throttle setting, the following sequence can be set:

phase 1 - delay time is 0 seconds - two cylinders of a wide face are actuated;
phase 2 - delay time is 5 seconds - two cylinders of the opposite wide face are actuated;
phase 3 - delay time is 10 seconds - one cylinder of a narrow face is actuated;
phase 4 - delay time is 15 seconds - one cylinder of the opposite narrow face is actuated.

The proposed design of the mould positioning system on the casting table relative to the mould bottom plate allows to change the algorithm (sequence) of actuation of pneumatic cylinders, excluding wedging of the mould with extended cylinder rods.
The implementation of the proposed improvements of the crystallising mould auxiliary systems both together and separately allows to extend the crystallising mould service life, to avoid contamination of cast ingots and workplaces around the casting machine with lubricant, with the final effect expressed in reducing the time of preparing for casting and increasing the productivity of the crystallising mould.
In accordance with the foregoing description and claims, the scope of legal protection is sought for the following subject matter:

1. A vertical casting mould used in the production of aluminium ingots containing a body with upper and lower flanges, characterised in that the mould body is made in the form of a prefabricated composite structure containing a casting frame and at least one water supply unit attached to the frame.
2. The crystallising mould according to claim 1, characterised in that the water supply unit is made of a material different from the material of the casting frame, such as stainless steel or titanium alloy.
3. The crystallising mould according to claim 1, characterised in that the water supply unit contains at least one water flow control valve, made in the form of a one-way pneumatic cylinder with a return spring and air exhaust from the under-piston space through the piston rod.
4. The crystallising mould according to claim 3, characterised in that the body of the water flow control valve has a coating made in the form of a shell made of a polymer material, and the shut-off element of the valve has a coating made in the form of a lining made of a polymer material.
5. The crystallising mould according to claim 1, characterised in that at least one pneumatic unit is installed on the lower flange, containing at least one pneumatic cylinder with at least one time-delay valve.
6. The crystallising mould according to claim 5, characterised in that the time-delay valve serves to provide a time delay in a range from 0 to 30 seconds.
7. The crystallising mould according to claim 1, characterised in that the water supply unit is attached to the casting frame by means of a detachable connection, in particular, a bolted one.
8. The crystallising mould according to claim 1, characterised in that the water supply unit is made of a corrosion-resistant material, such as stainless steel or titanium alloy.
9. The crystallising mould according to claim 1, characterised in that it additionally contains at least one of the following auxiliary systems: a cooling control system for the mould and ingots, a lubrication control system for ingots, including the supply and retention of grease, a positioning system for the mould on the casting table relative to the mould bottom plate.
10. The crystallising mould according to claim 9, characterised in that in the upper flange, there is a control system for the lubrication of ingots, and in the lower flange, there are air channels of the mould positioning system on the casting table relative to the mould bottom plate.
11. A vertical casting mould used in the production of aluminium ingots according to any of claims 1-8 additionally containing at least one of the following systems: a cooling control system of the mould and ingots, a control system for the lubrication of ingots, including the supply and retention of grease, a positioning system of the mould on the casting table relative to the mould bottom plate.
12. The crystallising mould according to claim 11, characterised in that in the upper flange, there is a control system for the lubrication of ingots, and in the lower flange, there are air channels of the mould positioning system on the casting table relative to the mould bottom plate.
13. The crystallising mould according to claim 11, characterised in that in the grease feeding outlet channels of the ingot greasing control system located in the upper flange, there are nozzles with shut-off elements able to open by the action of grease pressure.
14. The crystallising mould according to claim 13, characterised in that the shut-off element of the nozzle is made in the form of an O-shaped O-ring made of elastic material.
15. The crystallising mould according to claim 13, characterised in that the shut-off element of the nozzle is made in the form of a T-shaped valve made of elastic material.
16. The crystallising mould according to claim 13, characterised in that the opening pressure of the shut-off element of the nozzle is preferably 0.2-1.0 bar.
17. The crystallising mould according to claim 13, characterised in that the diameter of the outlet opening of the nozzle is preferably 0.4-1.2 mm, optimally 0.6-1.0 mm.
18. The crystallising mould according to claim 11, characterised in that at least one pneumatic unit is installed on the lower flange, containing at least one pneumatic cylinder with at least one time-delay valve.
19. The crystallising mould according to claim 18, characterised in that the time-delay valve serves to provide a time delay in a range from 0 to 30 seconds.
20. The mould and ingot cooling control system for the mould according to claim 11, which contains a water supply unit with at least one coolant flow control valve made in the form of a one-way pneumatic cylinder with a return spring and air exhaust from the under-piston space through the piston rod.
21. The control system of lubricating the ingots of the mould according to claim 11, which contains a lubricant feeding and retaining system, lubricant feeding outlet channels located in the upper flange of the mould body, while in the outlet channels, there are nozzles with shut-off elements able to open by the action of lubricant pressure.
22. The mould positioning system on the casting table relative to the mould bottom plate according to claim 11, which contains pneumatic units placed along the perimeter of the lower flange of the mould body, while pneumatic cylinders and actuation time delay valves are built into the pneumatic units.

Claims

A vertical casting mould used in the production of aluminium ingots containing a body with upper and lower flanges, characterised in that the mould body is made in the form of a prefabricated composite structure containing a casting frame and at least one water supply unit attached to the frame.
The crystallising mould according to claim 1, characterised in that the water supply unit is made of a material different from the material of the casting frame, such as stainless steel or titanium alloy.
The mould according to claim 1, characterised in that the water supply unit contains at least one water flow control valve, made in the form of a one-way pneumatic cylinder with a return spring and air exhaust from the under-piston space through the piston rod.
The crystallising mould according to claim 3, characterised in that the body of the water flow control valve has a coating made in the form of a shell made of a polymer material, and the shut-off element of the valve has a coating made in the form of a lining made of a polymer material.
The crystallising mould according to claim 1, characterised in that at least one pneumatic unit is installed on the lower flange, containing at least one pneumatic cylinder with at least one time-delay valve.
The crystallising mould according to claim 5, characterised in that the time-delay valve serves to provide a time delay in a range from 0 to 30 seconds.
The crystallising mould according to claim 1, characterised in that the water supply unit is attached to the casting frame by means of a detachable connection, in particular, a bolted one.
The crystallising mould according to claim 1, characterised in that the water supply unit is made of a corrosion-resistant material, such as stainless steel or titanium alloy.
The crystallising mould according to claim 1, characterised in that it additionally contains at least one of the following auxiliary systems: a cooling control system for the mould and ingots, a lubrication control system for ingots, including the supply and retention of grease, a positioning system for the mould on the casting table relative to the mould bottom plate.
The crystallising mould according to claim 9, characterised in that in the upper flange, there is a control system for the lubrication of ingots, and in the lower flange, there are air channels of the mould positioning system on the casting table relative to the mould bottom plate.
A vertical casting mould used in the production of aluminium ingots according to any of claims 1-8 additionally containing at least one of the following systems: a cooling control system of the mould and ingots, a control system for the lubrication of ingots, including the supply and retention of grease, a positioning system of the mould on the casting table relative to the mould bottom plate.
The crystallising mould according to claim 11, characterised in that in the upper flange, there is a control system for the lubrication of ingots, and in the lower flange, there are air channels of the mould positioning system on the casting table relative to the mould bottom plate.
The crystallising mould according to claim 11, characterised in that in the grease feeding outlet channels of the ingot greasing control system located in the upper flange, there are nozzles with shut-off elements able to open by the action of grease pressure.
The crystallising mould according to claim 13, characterised in that the shut-off element of the nozzle is made in the form of an O-shaped O-ring made of elastic material.
The crystallising mould according to claim 13, characterised in that the shut-off element of the nozzle is made in the form of a T-shaped valve made of elastic material.
The crystallising mould according to claim 13, characterised in that the opening pressure of the shut-off element of the nozzle is preferably 0.2-1.0 bar.
The crystallising mould according to claim 13, characterised in that the diameter of the outlet opening of the nozzle is preferably 0.4-1.2 mm, optimally 0.6-1.0 mm.
The crystallising mould according to claim 11, characterised in that at least one pneumatic unit is installed on the lower flange, containing at least one pneumatic cylinder with at least one time-delay valve.
The crystallising mould according to claim 18, characterised in that the time-delay valve serves to provide a time delay in a range from 0 to 30 seconds.
The mould and ingot cooling control system for the mould according to claim 11, which contains a water supply unit with at least one coolant flow control valve made in the form of a one-way pneumatic cylinder with a return spring and air exhaust from the under-piston space through the piston rod.
The control system of lubricating the ingots of the mould according to claim 11, which contains a lubricant feeding and retaining system, lubricant feeding outlet channels located in the upper flange of the mould body, while in the outlet channels, there are nozzles with shut-off elements able to open by the action of lubricant pressure.
The mould positioning system on the casting table relative to the mould bottom plate according to claim 11, which contains pneumatic units placed along the perimeter of the lower flange of the mould body, while pneumatic cylinders and actuation time delay valves are built into the pneumatic units.