Claims:WE CLAIM:
1. A lubricating agent for open steel casting process, comprising:
an oil with a mould powder and a dispersing agent in a ratio 14-16: 8-10 :1-2 respectively.
2. The lubricating agent as claimed in claim 1, wherein the oil, in weight percentage, comprises palmitic acid 4.6 – 32.5, oleic acid 37.0 – 63.5, linoleic acid 20.3-25.9, and linoleinc acid 0.7- 6.3.
3. The lubricating agent as claimed in claim 1, wherein the oil is having flash point at 260-330 degrees celsius, viscosity of 50-60 at 40 degrees celsius, viscosity pf 10-15 at 100 degrees celsius, moisture of 10-15 PPM, TAN of 0.1-0.2 mg of KOH/gm.
4. The lubricating agent as claimed in claim 1, wherein the mould powder, in weight percentage, comprises CaO: 20-45, SiO2 15-55, Al2O3: 0-12, Na2O+K2O: 0-20, F: 2-15, and MnO: 0-5.
5. The lubricating agent as claimed in claim 1, wherein the dispersing agent is a commercial available reagent with brand name FLUMIX 510.

, Description:LUBRICATING AGENT FOR OPEN STEEL CASTING PROCESS

TECHNICAL FIELD
[0001] The present disclosure, in general, relates to the field of lubricants and, in particular, relates to a lubricating agent for open steel casting process.

BACKGROUND
[0002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] FIG. 1 illustrates a schematic diagram of steel billet casting machine. In FIG. 1, the continuous casting of steel requires lubrication between a water-cooled copper mould table 102, which is being continuously oscillated through an oscillating arm 104 by an oscillator 104, and a solidifying strand 106 which is being drawn by pinch rolls. There are mainly two types of lubricants which are in use for casting of smaller cross section of steel called billets. One type of lubricants includes naturally found rapeseed oil or synthetically prepared oil, and other type of lubricants includes a casting powder which is a mixture of different oxides found in earth crust and carbon.
[0004] Both kinds of lubricants have merits and demerits associated with them. Oil lubrication provides better heat transfer in the meniscus region whereas the casting powder forms liquid slag after melting so as to provide better thermal stability at the lower region of the mould. Also, oil casting does not require submerged pouring of liquid steel into the mould, and hence having better sequence length and lesser refractory cost. On the other hand, casting with the mould powder gives better product as the surface quality of billet cast and the internal structure of billet are far superior to oil cast billets. Casting with the mould powder eliminates the spitting/sparkling phenomena which is obvious in the oil casting.
[0005] The casting powder provides at least five major function of this mould powder during continuous casting of steel, for example, lubrication between mould and solidifying strand, controlling heat transfer between mould and strand, control on reoxidation of liquid steel on the top of the mould, absorption of inclusions from steel, and preventing solidification of steel from the top of the mould.
[0006] However, the usage of the casting powder in open casting is difficult as the powder gets entrapped in the billet as the free-falling stream of liquid steel directly falls in the casting powder. The powder entrapment becomes severe with the presence of Electro Magnetic Stirring (EMS) and affects the internal quality of billet.

OBJECTS OF THE DISCLOSURE
[0007] In view of the foregoing limitations inherent in the state of the art, some of the objects of the present disclosure, which at least one embodiment herein satisfy, are listed hereinbelow.
[0008] It is a general object of the present disclosure to provide a lubricating agent for open steel casting process.
[0009] It is an object of the present disclosure to propose a method to produce a new class of mixed lubricant with enhanced lubrication properties applicable to open continuous casting of steel billets.
[0010] It is another object of the present disclosure to propose a method to produce the new lubricant with enhanced lubrication properties applicable in a continuous steel casting process, in which the spitting in the mould is reduced significantly along with corner cracks.
[0011] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.

SUMMARY
[0012] This summary is provided to introduce concepts related to a lubricating agent for open steel casting process. The concepts are further described below in the detailed description. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.
[0013] In an embodiment, the present disclosure relates to a lubricating agent for open steel casting process. The lubricating agent includes an oil with a mold powder and a dispersing agent in a ratio 14-16: 8-10 :1-2 respectively.
[0014] In an aspect, the oil, in weight percentage, comprises palmitic acid 4.6 – 32.5, oleic acid 37.0 – 63.5, linoleic acid 20.3-25.9, and linoleinc acid 0.7- 6.3.
[0015] In an aspect, the oil is having flash point at 260-330 degrees celsius, viscosity of 50-60 at 40 degrees celsius, viscosity pf 10-15 at 100 degrees celsius, moisture of 10-15 PPM, TAN of 0.1-0.2 mg of KOH/gm.
[0016] In an aspect, the mold powder, in weight percentage, comprises CaO: 20-45, SiO2 15-55, Al2O3: 0-12, Na2O+K2O: 0-20, F: 2-15, and MnO: 0-5.
[0017] In an aspect, the dispersing agent is a commercial available reagent with brand name FLUMIX 510.
[0018] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
[0019] The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and methods that are consistent with the subject matter as claimed herein, wherein:
[0020] FIG. 1 illustrates a schematic diagram of steel billet casting machine;
[0021] FIG. 2 illustrates particle size distribution of pulverized mould powder;
[0022] FIG. 3 illustrates a pictorial comparison of decrease in spitting from the mould with a lubricant agent produced in accordance with the present disclosure; and
[0023] FIG. 4 illustrates a pictorial comparison of an improvement in internal quality of billet with a lubricant agent produced in accordance with the present disclosure.

DETAILED DESCRIPTION
[0024] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[0025] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0026] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a”, “an”, and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “includes”, “consisting” and/or “including” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
[0027] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0028] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0029] Embodiments explained herein pertain to an innovative solution to control cracks by developing a new class of lubricant for open casting, where a uniformly dispersed mould powder in lubricating oil, used for open continuous casting of steel billets, will be prepared and to be continuously fed into the mould. This will take care of the positive impacts of both oil and powder during continuous casting of billets.
[0030] Although there are challenges to uniformly disperse the powder in liquid medium and as well as for longer duration of dispersion, a detailed study is carried with different dispersing agents to develop a lubricant with uniform and longer duration of dispersion. This includes identification of suitable dispersing agent to improve the dispersion as well as the duration of dispersion and optimisation of dosage of identified dispersing agent.
[0031] Also, the technical solution provided by the present disclosure is to reduce the thermal conductivity of oil lubrication which is applied for open casting of billet by adding fine powders which is completely dispersed in the oil medium. The characteristics of the new lubricant is a fully dispersed fine powder particles in an oil medium which can stay dispersed for more than 45 days for process stability and keep the high temperature properties intact. The powder once in touch with the liquid steel will melt and form a slag layer which will help in controlling the horizontal heat transfer in the mould and a liquid slag layer on the top of the mould will prevent spitting of liquid steel out of the mould.
[0032] In an embodiment, the present disclosure provides a lubricating agent for open steel casting process. The lubricating agent includes an oil with a mold powder and a dispersing agent in a ratio 14-16: 8-10 :1-2 respectively.
[0033] In an aspect, the mould powder dispersed in the oil can be any mould powder used for continuous casting of steel in finer form and without carbon content in it. The mould powder includes different oxides from minerals such as, CaO, SiO2, Al2O3, MnO, CaF2, Na2O, K2O and other oxides. An exemplary composition range for these minerals is mentioned below in the Table 1:

Table-1: Composition of lubricating powder
Sl. No. Component % Composition
1 CaO 20-45
2 SiO2 15-55
3 Al2O3 0-12
4 Na2O+K2O 0-20
5 F 2-15
6 MnO 0-5

Table 2: Technical specification of Oil
Sample Flash Point (OC) Viscosity at 40OC Viscosity at 100OC Moisture (PPM) TAN (mg of KOH/gm)
Oil 260-330 50-60 10-15 300-600 0.1-0.2

[0034] Further, the particle size distribution of the mould powder has a major impact on preparation of slurry with uniform dispersibility. Accordingly, the mould powder was ground using a vibratory cup mill for 5 minutes so that fine size can be obtained. The fine powder size distribution was measured using a laser particle size analyzer. The results are shown below in FIG. 2. FIG. 2 illustrates particle size distribution of pulverized mould powder. Most of the particle must be uniform in size and should fall in a narrow range to get the slurry with uniform dispersibility.
[0035] To achieve the uniform dispersion for longer duration, a dispersing agent is needed to mix the powder in oil medium. Since the mould powder contains different basic and acidic oxides along with free carbon, it is very difficult to select the suitable dispersing agent. For the selection of dispersing agent, many characterization techniques can be used to evaluate the performance:
• Flow Point Measurements
• Relative Flow Rate Measurements
• Settling Study

PREPARATION OF SLURRY AND DETERMINATION OF ITS STABILITY:
[0036] Once the suitable dispersing agent and optimizing the dosage of the same is identified, oil is taken in a tank and required quantity of that dispersing agent is added to the oil. Then, the oil is mixed with the dispersing agent using a rotating shear stirrer with >3000 rpm for 15 minutes. Once the dispersing agent mixing is over, the ground powder was gradually added to the oil very slowly while rotating the stirrer at high rpm to have uniform mixing of powder in the oil. The stirring process was carried out for about 60-120 minutes to ensure complete dispersion of powder.
[0037] The dosage of dispersing agent and type of dispersing agent used are optimized on the basis of setting study, where the settling time was observed for 45 days.

Plant Trial:
[0038] Based on the settling study, the optimized dispersing agent with its dosage is used for plant trial to study the effectiveness. The plant trial results are presented in FIGS. 3 and 4 where it can be seen that there was improvement in heat flux values and also there was reduction in mould spitting during the trial. FIG. 3 illustrates a pictorial comparison of decrease in spitting from the mould with a lubricant agent produced in accordance with the present disclosure; and FIG. 4 illustrates a pictorial comparison of an improvement in internal quality of billet with a lubricant agent produced in accordance with the present disclosure.
[0039] Also, Table 3 shows comparison of water delta to user in the new lubricating agent with the dispersed powdered in comparison to the oil based lubricating agent.

Table 3: - Decrease in water delta T due to use of new lubricant with dispersed powder
Oil Oil+ Powder
Water delta T for casting speed of 3.8 m/min 7.4OC 6.3OC

[0040] Thus, the present disclosure provides a new class of mixed lubricant with enhanced lubrication properties which is applicable to open continuous casting of steel billets.
[0041] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases, it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[0042] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.
[0043] Furthermore, those skilled in the art can appreciate that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.
[0044] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.
[0045] While the foregoing describes various embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from the basic scope thereof. The scope of the present disclosure is determined by the claims that follow. The present disclosure is not limited to the described embodiments, versions or examples, which are included to enable a person having ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person having ordinary skill in the art.

TECHNICAL ADVANTAGES
[0046] The present disclosure provides a lubricating agent which when used in billet casting, decreases the heat transfer in the continuous casting mould in comparison to, when oil is used as a lubricant. This is due to the dispersed powder which melts on the liquid steel top and creates a solid slag film between the solidifying strand and mould.
[0047] The present disclosure provides a lubricating agent which helps in preventing the spitting of liquid steel out of the mould by creating a liquid slag layer on the top when used during billet casting.
[0048] The present disclosure provides a lubricating agent which helps in improving the internal quality of billet when used during open casting of billets.