The Machining Strategy Improvisation For Hot Steel Rolling Mills

Overview of the Manufacturing Process

Manufacturing is the process of converting raw material into useful product. In general, manufacturing process is classified into four types (I.e. Casting, Machining, Molding, and Forming). Among the four different processes, each of them is used to manufacture a different set of products (Basile and Gallucci, 2011). Rolling process is classified under the Forming process. Forming is the process of change the shape of the material by plastic deformation process (Chakraborty and Rath, 2013). Commonly the rolling process is classified into two types based on operating temperature. And they are hot rolling and cold rolling. Here the hot rolling process is highly preferred because the material is heated nearly to its recrystallization temperature. At this temperature, the material is soft enough to change the shape of the material by giving the pressure on the material. And also, the hot rolling process does not cause any residual stresses on the final product (Chansauria, 2016).

Figure 1 Rolling process

Here the heat is also used with the pressure. So, the required magnitude of pressure in hot rolling is lower than the pressure required for cold rolling in the same material. But the hot rolled products have lower yield strength than the cold rolled products (Chansauria, 2016). Also, the hardness of the cold rolled product is quite higher than the hot rolled product. When comparing the hot rolling process with the cold rolling process, the cold rolling process consumes more labor and energy to carry out the forming process. So, the products made by the cold rolling process is quite costlier than the products made by the hot rolling process. This is the reason behind the use of cold rolled products for finishing applications.  But, cold rolled products require further processing for removing the residual stresses. These are the general overview of the rolling process.

In the previous work, the detailed overview of the rolling process and various important things about the rolling process efficiency are studied. In this thesis, the author mainly concentrates on the performance improvement in the rolling process (CHEN, 2014). The overall performance of the rolling process depends on the various factors like shape, size, applied load, and material etc. (Pater, 2003). Among them, RPD (Roll Pass Design) is the important parameter which affects the overall rolling performance. Here, the quality of the rolled products also depends on this factor. So, the author specifically concentrated on the RPD. Roll Pass Design is the term used in rolling industries. It is widely used to reduce the large profile size into the small profile size. This changing of profile size in RPD is achieved by conducting number of passes (Permutation tests for stochastic ordering and ANOVA, 2009). The reduction of large profile size into small profile size process is not done by the single pass. Because, reducing the large size in the single pass requires too big rollers and higher energy. It also yields poor final quality of the finished product (Regulski, Rojek and Kusiak, 2014). Here the tolerance and size accuracy is not up to the standard. So, this process is carried out by set of consecutive passes. In each passes, the size and shape are modified gradually to ensure the accuracy of the final product. Here the various roller arrangements are shown. All the different variety of arrangements are used for various purposes (Rizzo and Pagliassotto, 2017). And they are, given in the below screenshot.

Classifications of Rolling Process

Figure 2 Roller Arrangement.

In this thesis, the author discussed the performance improvement of the rolling process by optimizing the RPD value. For that, the author used the data collected by various students. Here the author combined all the individual dataset into the database. From the above-given figure, the current practice of the metal industries is described. Here, the collected database is analyzed to ensure all the data values which are collected from the appropriate sources. In other words, this process is called as validation of the database (Rolling Process Modeling Report, 2014). This validation process provides adequate details about the RPD.

Figure 3 Numerical Simulation of the Final Pass Deformation

In multi-pass rolling process, huge volume of information are gathered. These can be easily analyzed by advanced techniques in the modern world. By using the appropriate scientific and statistical tools and techniques, these data sets are analyzed. (Real-time basis) From the analyzed records, the various spectrum of the long rolling process with a number of passes are identified (Rolling Process Modeling Report. Finite-Element Model Validation and Parametric Study on various Rolling Process parameters, 2015). Here the collected information is converted into RPD database. RPD database provides rich information for the RPD designers during the roll pass design process.

In the industrial manufacturing process, the rolling process is one of the most common processes. The below given things are the common factors which shows the impact on the overall quality of the final product (Sawalhi, n.d.).

Specification of the product is a report that contains the set of information regarding to the various characteristics of the product. Here, all the nominal features of the product are described. This document also provides various geometrical details as well as dimensional details about the product (Schneider et al., 2011). Here the geometrical details means the shape of the product, angle and orientation etc. And the properties that are measure in some magnitude is known as dimensional properties. For example, consider the standard length or diameter. These are comes under the dimensional properties. For this information, we can use the standards (Both national standards as well as international standards etc.). These parameters are highly impacts on the final quality of the product.

During the rolling process (multi pass rolling), the material undergoes to the series transformation in terms of shape, size and mechanical properties etc. Here the cross sectional area of the feed material is reduced along with the increase of the span of the material (Segawa, 2011). During the rolling process, the shape of the material is reduced gradually by the various passes. But the chemical composition of the material remains constant during this process. In rolling process, there is no noticeable change occurred in the chemical composition. By the applied force or pressure, the internal crystalline structure of the material get modified. These deformation is occurred by following factors. The first and foremost factor is temperature gradient between the various rollers. This phenomenon is only present in the hot rolling process. In hot rolling process, the various rollers are kept at various temperatures. This difference in the temperature causes inter-crystalline structural changes. Deformation extent also affects the transformation substantially.

Difference between Hot Rolling and Cold Rolling

Morphometric information of the various different rollers are defined with the help of the roll grooves (Shlomchack, Mamuzic? and Vodopivec, n.d.). Morphometric information help to support the concepts said in the previous point. So, both transformation in shape as well as the morphometric details has the close relation between them. These information can be described in the form of groove drawings. Here the groove drawings provides the morphometric details related to the various roller grooves relative positions.

Roller specification is also an important feature which affects the quality as well as performance of the rolling process. Roller is a working tool in the forming process (Siciliano, 2013). In general, the roller specification details contains the details about the nominal information about the roller, surface topography of the roller, micro structural behaviors of the roller materials, chemical compositions of the roller material etc. The orientation and alignment of the various rollers in the system also considered. Here, the buffer stock of material is also considered to maintain the groove morphometric shape. Because, the roller grooves lost its preferred morphometric shape during its continuous usage (Tober, Anopuo and Maier, 2012). The grooves are redressed to correct the blended roller groove to the preferred roller grooves. This phenomenon mainly depends on the cooling methodology employed for cooling the tools or rollers. In some cases, it is also affected by the type of lubrication used.

Complementary documentation is a kind of document. It provides the various information about the feed preparation process (Tost and Vasilieva, n.d.). In rolling process, the feed preparation process consists of the various activities like the initial heating techniques, finishing operations etc. In this stage, the cooling techniques as well as straightening techniques are described. It also consists of the various auxiliary tools information.  Here, the auxiliary tools are the tools which used for guiding the rolled material into the deformation area of the rollers.

Figure 4 Steel Rolling Mills

In the above-given figure, the typical steel rolling process is shown. Here, the steel billet is feed into the system to reduce the size of the billet as well as manipulate the profile of the system (Wang, 2011). The above figure shows multi-pass round shape hot rolling process.

Various defects involved in the Rolling process

As similar to all the technologies and processes, rolling process also have some difficulties. Today the evolution of the technological advancement on the rolling process is too high. Modern rolling mills have the precise control system. Unlike the conventional process, the modern machines use the bunch of sensors to monitor various process parameters involved in the rolling process (Wang and Zhang, 2011). Here the major process parameters are feed rate of the material, temperature of feed, temperature of rollers, speed of the rollers, and pressure on the ram etc. Some problems may occurred in the rolling process. These problems are occurred due to various reasons. In this section, the brief overview about the various problems currently present in the rolling process is given. These problems are the major reason for poor quality of the overall process. And the various problems involved in the rolling process are described below.

Factors Affecting the Performance of Rolling Process

Major problem involved in the rolling process is calibration of roller. Today, this work mostly done by the computer assisted systems when problems are occurred. During the rolling process, the each rollers exerts the huge magnitude of forces (Cortina and Nouri, 2003). At this higher forces, the bearing system get damaged. It causes errors in the size of the final output. In some cases, the variation of the actual size with the input size is too high. In modern rollers, this problems are reduced by the feedback system (Cortina and Nouri, 2007). Here the feedback system continuously measures the size of feed and output. A processing system compares this values with the actual values. If there is any deviation with the programmed values, then it shows the notification. This method is also carried out after the problem occurs.

In hot rolling process, there is a possibility of oxidation on roller surfaces. This oxidation layer responsible for the dimensional errors. It reduces the accuracy of the entire processes. This layer is also responsible for poor surface quality. 

Rollers used in the rolling mills.

Rolling mills contains the set of rollers as a work tool. Rollers are responsible for the deformation process. In rolling process, the load or pressure given through the rollers. Roller material is generally selected based on the feed material (Couch and Wang, 2003). In general, the hardness of the roller must be higher than the work material. Rollers are commonly used by all the mining, metallurgical and petroleum industries etc. In Russia ‘Uralmashplant’ is one of the leading suppliers for the rollers. 

They are specialized in the production of heavy machineries and spare parts for the mining industries, construction material manufacturing industries, power engineering machines and metallurgy industries. From the last decade, they are the market leaders. They producing the various machine parts for the various industries. The manufacturing process which carried out for producing the rollers is given below.

Figure 5 Rollers

The above figure shows the roller machining process. In this process, the work material (Roller) mounted on the lathe spindle. And it is continuously rotated by the electric motor. During this process, the relative motion between the tool and work material causes the material removal.

Figure 6 Roller Manufacturing

The above-given image shows the relative position between the tool and work material. Mostly the tool used in this process having the higher red hardness. Mostly this tools are operated by the semi-automatic conditions. Here the tool feed is given by the automatic system. It gives the speed, feed and depth of cut based on the input parameters. In recent days, mostly all the companies are using the CNC lathes instead of other conventional and manual operated lathes.

Importance of Roll Pass Design (RPD)

Figure 7 Roller Machining

Figure 8 Turning of Rollers by using lathe.

As similar to the normal machining process, here also the extra materials are rejected in the form of the chips. In the above figure, the continuous chips are shown.

In this case, the importance of the collected details about the measurements of the machining process is actually required to perform well. This details are identified from the experimental methods (Dangayach and Gupta, 2016). To improve the accuracy of the results and findings, the working environment are made similar to the real conditions. Because, this technique yields higher reliable and realistic results.

There are number of RPD studies conducted by various persons as well as the standard machining hand books which finally advices the set of principles. And those principles reveal the following things and they are described in the following sections. The first thing is about the sustainability of the entire system (Danyluk and Dhingra, n.d.). This phenomenon is an important factor, which helps to identify the overall performance of the system and processes. This analysis also reveals the truth about the overall resource consumed for the processes as well as the profit earned from the processes. The overall effectiveness of the manufacturing process mainly depends on this ratio. The good and profitable manufacturing process must ensures that the net profit must be higher than the overall cost consumed.

Here, all the principles are classified into many specificities like various mechanical attributes of the process, dimensional tolerance, load values for rolling processes, power and energy spent for the machining process, and emission of carbon etc. Even though the rationality of the specificities in many cases are not up to the standard (Das and Pradhan, n.d.). In most of the cases, it does not work. For example, the geometric tolerances of the systems are found and defined by the appropriate methods and techniques.  One more example is the load definition. Here, the loads excreted by the rollers are not found and defined accurately. To find the load variables accurately, there is no techniques and methods available. For calculating this phenomenon, there is no single standard procedure. There are many number of techniques which are currently available for calculating the load excreted by the rollers. And also the design limits only found for the normal loading conditions. These specificities are not suitable for the special loading conditions. Because, they are developed according to the requirements of the normal loading conditions (Denkena and Hollmann, 2013). These kind of problems are occurred because of the assumptions taken. Here, most of the assumptions are unrealistic. For example, consider an assumption “there is no wear in the rollers during the usage” which means that the wearing behavior is not considered here. But in the actual case, the roller material undergoes to the continuous wear during the continuous usage.

Various Roller Arrangements and Their Purposes

There are number of variations are involved in the normal rolling process (Fan, Zang and Jin, 2016). During material changing process, the rollers temperature and some other phenomenon are changing continuously. Consider the temperature of the rolling mill’s roller during the process. It may get increased in some cases or decreased in some cases. But, one thing is clear that it is not same in all the cases. It gets varied. So, the rolling mill roller requires some time to get back to its original position. (Return to its original temperature). So, the feed of each and every piece of raw material is responsible to create an impact on the rolling mill rollers. In some cases, there is a possibility of great damage or accident by the faults done by the operators (Gama and Mahfouf, 2007). These accidents cause mortal accidents also. Other than the operator’s faults, there are some other reasons also responsible for that. For example, consider the internal structural problems in the rollers, sudden power cuts, and inadequate cooling process. These are seems to be small problems, but they have the potential to cause huge consequences.

Here, the probability for occurring accidents are quite high in all industrial processes. These situations are commonly termed as abnormal conditions or nonstandard conditions. During this condition, the roll failure leads to injuries for both machines and operators. It also impacts on the final quality of the rolled product (Ginzburg and Ballas, 2000). So, there are many risks associated with the roller failures. So currently, there are number of researches going to reduce the effects of the risks involved. But, it is difficult to identify and mitigate all the reasons for the accidents. The main aim of this researches is to reduce the possible risks to improve the safety of the operation.

The Repositories databases are translated into the structured database. These repositories databases are gathered in the previous research. The repositories database has a multi-dimensional structure. These databases need to be designed to get the morphometric aspects regarding the rolling passes. It is considered as the main aim for the repositories database (Goos and Meintrup, n.d.). The structure database is used to make the multivariate analysis. This analysis helps to infer the relationship in the statistical way. Also, infer the trends and patterns of interaction between passes. The essential feature of this statistical relationship is to infer a large number of real events. The performance of rolling campaigns in industry is considered as the real event. The output models are used to redesign the existing process. This kind of redesign process is used to reduce the critical issues regarding the rolling process. Also, it is used to design a new kind of processes.

Performance Improvement of Rolling Process

The implementation of methodology has some stages. In that, the first stage is the methods would be applied for the statistics on the existing database. This stage is represented as the main subject of the existing articles. The analysis of industrial records is an essential one. So, it should be well understood. The intelligent system is used here to learn and reduce the performance of the rolling mills. So, it could be useful regarding the product quality. And the production should be consistent (Guerrero et al., 2010).  The operators have a big amount of data regarding the rolling mill. These information are not used in the past. The industry has many benefits. In that, the development of analytical tools is used to manufacture the database easily. It is considered as the great advantage for the industry. The industry needs some developments to make the financial contribution while rolling a huge amount of steel products.  The industry has a competitive environment in steel manufacturing regarding the prevention of standardization and open sharing. It is considered as a one stage. And the other side is publishing the records (GUO, 2014). For that, the generic format should be used. This general format is used to display the summative key performance and technical parameters. According to the detailed information, the existing records should vary in custom and conventions. There are no standardized codes used to measure the dimension for technical RPD drawings. Also, the roll wear is mentioned as the different criteria. But, the generic format is not required in the mathematical analysis. And the databases should be structured to embrace the control factors. It is corresponding to the hierarchy of the influence (Han and Li, 2018). The repositories records should be translated into suitable analytical function regarding the mathematical.

The theoretical and experimental methods are existing for the rolling process. The methods could be known as the finite element method and theory of plasticity. The physics of the deformation is not well understood regarding the rolling process. The deterministic models are used here, to analyze the effects and causes regarding the rolling factors. But, this method is not enough to make the reliable prediction (HOU, 2013). So, the multivariate analysis is introduced as a promising strategy. The verification of mathematical methods seems to be rich. For that, it needs many techniques. They are descriptive techniques, multivariate distributions and inferential statistics. Here, two concepts are used to uncover the latent structure regarding the variables (Huang, 2011). These methods are used to mitigate the spectrum of a large number of variables to a small number of variables. The sufficient analysis is needed in the process. So the statistical analysis is required to merge with methods such as empirical and theatrical methods. It leads to making the hybrid models. So, the rules and the guidelines are needed to be improved to enable the measurement of plastic flow in the roll grooves. Here the reliable predictions help to reduce the repositories database issues. These issues could have the tendency to overfill or under fill the roll grooves (Jing, 2014).

Factors Affecting the Overall Quality of Final Product in Rolling Process

Also, the forms and functions are used to make the multivariate analysis. But, it is not the best one for implementation of actual industrial repositories database. Also, the reverse translation is required to be done with an adequate solution. This translation is used to enable the realistic control in the rolling mill (Judd, McClelland and Ryan, n.d.). The represented models need to be described for controlling and measuring the factors. Because, measuring the stress could be not easy in the deformation zone. But the issues such as roll torque and the roll separating forces could be measured correctly (K, 2012). And the measurement of plastic flow regarding the rolled material seems to be hard. Generally, the roll grooves are measured accurately. The extension of rolls could be expressed in rolled mass. It is not enough. The rolled length, sliding velocity, and the deformation zone geometry needs to be measured. In the process, the description of the deformation zone is provided based on the geometry and dimensions regarding the rolled bar cross section (Kini and Shivpuri, 2000). The deformation is also defined by using the roll groove morphometry. The technical drawings are used to define the additional information regarding the roll grooves. The rolling schedules are also used to define the deformation. These schedules could be the sequence of subsequent passes. The information which is existing in the process. could not be standard. Because, various kinds of conventions are mostly used in the process. So, the generic mathematical forms are required in this process. These forms are used to make the subsequent analysis. To find a solution for the problem, the class of symmetrical long products should be considered as the first and best approach.

Features of the structured database

The groove drawings are translated into the mathematical functions. It is one of the features regarding the structured database (Kondo, 2011). Also here some general functions are used to represent the diverse spectrum regarding the groove contours. These functions are used in starting stage, finishing stage and intermediate process. It is done by the different kind of numerical values and their components. The main goal of this project is to achieve the highly symmetrical products only on the first quadrant of the Cartesian coordinate system. The groove morphometry is represented by the general scheme. It is represented in the diagram.

Totally nine parameters are represented in the diagram. First, the A1 parameter is used to represent the center of the groove. And the A2 parameter is used to represent the starting point of the analytical function. The separation point regarding the hot metal and the groove surface is mentioned by the A3 parameter. Then the A4 parameter is used to represent the end of the analysis function. It is also considered for the starting point of the groove fillet. Also, the intercept of the extended analytic function is mentioned as the A5 parameter. The lateral spread point is considered as the A6 parameter (Kurotsu and Segawa, 2014). Also, the radius parameters are mentioned. The radius of the groove meridian is considered as Rs. It must be in the Centre of the groove. And the radius of the curve on the A6 is mentioned at Rb. Rc is mentioned as the parameter for the groove filet. The function f(x) is used to represent the function for the segment connecting the points A2 and A4. The width is also represented in the diagram. The lateral width of the rolled bar is mentioned as Wb. Abscissa for A5 is mentioned as Wk.

Various Defects Involved in the Rolling Process

The proposed analysis needs to identify the pass entering and pass existing morphometry. Two different kinds of phases are shown in the below pictures. They are square-oval and oval-round (Lenard, n.d.). The radius values are mentioned. The diagram of the pass sequence round is mentioned regarding the oval.

In this process, Chebyshev coefficient is applied for the rolling process. To reduce the thickness or skewness of the large material, there are twelve passes or rounds placed on the material. In each round, the thickness of the material will be reduced. Chebyshev coefficient is a mathematical technique which is used to define and calculate the results of descriptive statistics (Li, 2011). Totally, there are 12 rounds in the descriptive statistical results and for each and every round the statistics were calculated and updated. The results of each and every round were updated in every round (Li et al., 2015). From Round 0 to Round 11, there are 12 rounds and in that different Chebyshev coefficient technique were identified. The different Chebyshev coefficient functions are the mean value, standard error, minimum, maximum, range, skewness, largest, smallest, sum, count, kurtosis, sample variance, mode and standard deviation etc.

For the Round 0, the descriptive statistics for the Chebyshev coefficient is applied to the material and this process is also called as initial process and in this process the majority of the thickness will be reduced from the material. The confidence level for this round 0 is ninety five percentage and the value get the confidence level is 0.578754.

The descriptive statistics and Chebyshev coefficient for the round 1 is lesser than the initial skewness and thickness is reduced slightly. The value for the round 1 after the different analysis is 0.493632 and hence the confidence level is approximately 95 percentage.

The Chebyshev polynomial or coefficient for the round 2 is even smaller than the round 1. Because, after analyzing the different things like mean, median, and skewness etc. the confidence level for the round 2 is 0.0995157. Hence, the thickness of the material is reduced.

For the Round 3, the descriptive statistics for the Chebyshev coefficient is identified by analyzing the different function and the confidence level for this round 3 is 95 % and the value get for the confidence level is 0.0131975

The descriptive statistics and Chebyshev coefficient for the round 4 is calculated using the skewness of the material. The value for the round 4 after the different analysis is 0.0013057 and hence the confidence level is approximately 95 percentage.

Advanced Techniques Used for Accurate Control of Rolling Process

The descriptive statistics for the Chebyshev coefficient for round 5 is identified by means of different calculations. After analyzing the different things like mean, median, skewness etc. the confidence level for the round 5 is 0.000103088.

The Chebyshev polynomial or coefficient for the round 6 is lesser than the previous analysis. The total confidence for the round 6 is 95 percentage and the confidence level is achieved after analyzing the different factors on the material and the confidence level value is 6.77202E-6. Hence, the thickness of the material is reduced.

For the Round 7 the descriptive statistics for the Chebyshev coefficient and the confidence level for this round 7 is 95 % and the value get for the confidence level is 3.80961E-7.

The descriptive statistics for the Chebyshev coefficient for round 8 is done and the thickness of the product is reduced. The value for the round 8 after the different analysis is 1.87408E-8 and hence the confidence level is approximately 95 percentage.

The Chebyshev polynomial or coefficient for the round 9 is analyzed by doing different processes. After analyzing the different things like mean, median, skewness etc. the confidence level for the round 9 is 8.19035E-10.

For the Round 10, the descriptive statistics for the Chebyshev coefficient is lesser than the previous analysis. The total confidence for the round 10 is 95 percentage and the confidence level is achieved after analyzing the different factors on the material and the confidence level value is 3.55791E-11.

The descriptive statistics for the Chebyshev coefficient for round 11 in this the final result is achieved. The confidence level for this round 11 is ninety five percentage and the value get for the confidence level is 1.27287E-12. Hence the thickness of the material is reduced. The final value is also given for the rolling process.

Here, the various radar diagrams developed based on the above given details are shown below. It gives better understanding (LIU, 2010).

ANOVA is a short form of Analysis of variance. By using this process, the collection of different statistical methods are achieved.  ANOVA is mainly used for statistical analysis and it is also used to observe the variance of the particular components (Luo, n.d.). The Analysis of variance is also provide a technique called statistical test and by using this technique, the generalization of the two groups id done using the t-test.  Using this ANOVA, ‘analysis of mean’ is achieved and this feature is also used to identify the variance. But the values produced by the analysis of mean gives higher variance and produces the better result values. These are the features of the analysis of mean (ANOVA and ANCOVA, 2012).

Analysis of variance is having a technique called statistical method or model. The term ‘statistical method’ refers to the mathematical model and using this mathematical model the different process is achieved. The different processes in the statistical model are probability distributions, hypothesis tests, statistical estimators etc. and among these different processes, the statistical estimator model is implemented and using this model the different estimations are done for the rolling metal forming process (Mao et al., 2012). This analysis of variance is mainly introduced for the rolling process or a metal working process. The main theme of the ANOVA is to reduce the metal thickness to form the thickness uniform.  Using this statistical estimator model, the different pairs of rolls are identified and this process is also used to make the thickness uniform after reducing the thickness (Mao et al., 2012). There are different features of the analysis of variance are existed. They are comparing differences among the two groups and compares the number of variations, and then observing the experiments which are executed with the groups. These are the different common features of the ANOVA.  This ANOVA is slightly similar with the T-test and almost all the features and process of these techniques are similar. The technique in the ANOVA is statistical technique and it is used for comparing the means. The T-test is used to compare the populations. These are the small comparison and these are the main comparison for the T-test and ANOVA.

There are different decisions in the ANOVA and each and every decisions are used to make the best decisions. In this scenario, the database for the ANOVA is implemented and for storing and retrieving the data, excel sheet is implemented to understand the concepts. For implementing the ANOVA in excel data base, there are two main things considered. They are given below.

• A typical way to deal with make sense of a solid treatment strategy is break down the time it takes for the patients to be using this technique. We can utilize a measurable system which can think about these different processing tests and it also has to know how extraordinary these examples are from each other. Such systems, which thinks about the examples based on their methods, is called ANOVA.
• ANOVA is a procedure which is used for statistical analysis and it is utilized to check if the methods for at least two gatherings are altogether not the same as one another. This feature will also checks the effect of at least one factors by looking at the methods for various examples.

There are two kinds of ANOVA. They are one way ANOVA and two way ANOVA

One way ANOVA

ANOVA reveals to us that something like two gatherings are not the same as one another. However, it would not reveal to us which bunches are unique. On the off chance, that our test restores a noteworthy f-measurement, someone needs to execute the post-hoc test to let us know precisely what kind of bunches have a distinction in modes. Along with that we also made reference to the means to perform ANOVA (one way) alongside a post-hoc test. These are done in the excel database for storing the contents.

Two way ANOVA

This ANOVA explains us using the different principle impact and the cooperation impact. The fundamental impact of this kind of ANOVA is always higher. Whereas, the impact of the different kinds of analysis will be done and those would be estimated independently. While, the collaboration impact is where both analysis and identifications are considered in the meantime.

Characteristics of ANOVA

There are different characteristics of ANOVA and the characteristics are given below.

ANOVA is mainly has some features and functionalities that are helpful for the different investigations such as comparative or relative analysis, the different outputs are achieved using the ANOVA. There are two types of ANOVA like one way and two way ANOVA which are already explained. The other characteristics of the ANOVA are based on analyzing and examining the principles and that are used to control by a proportion of two variances (one way and two way). This proportion is autonomous of a few conceivable modifications to the trial perceptions: Adding a consistent to all perceptions may not modify the importance of the ANOVA. Duplicating all perceptions is another importance character of the ANOVA and using this feature, it is very easy to modify the different contents in the ANOVA. So, it is very important to find and analyze the various features of the ANOVA. The ANOVA factual hugeness result is free of consistent pre-disposition and scaling blunders. Additionally, the different units are used in the ANOVA for the different processes.

It is a statistical tool and also a method of statistical evaluation. It is used to learn the relationship for closeness between more than two variables. The variables are held to be correlated when one of the movement of variable is complemented by the alternative movement of variable (Meier, Golz and Hammelmann, 2007). This specific type of exploration is useful when a researcher needs to found if there are likely construction between the variables. If correlation is found between the two variables that means while there is a logical variation occurs in one variable, there is also a logical variation occurred in the other variable. The variable change occurs together over a certain time of a period. If the correlation is found, then it needs to measure the statistical values.  This statistical values can be positive or negative.  (Miller, n.d.). If the positive correlation is existed, it will increase the one variable concurrently with the other. If the negative correlation is existed, it will decrease the one variable after the other variable increases. A correlation of the study is very useful to apply in practical life. The reasons are,

• Many variables displays the certain kind of relationship like as sales and demand, expenditure and income, and much more. With the help of correlation analysis, the amount of the relationship is measured between the variables.
• The closeness of variable is defined, then the evaluation of the value for unidentified variable offered the value for other variable.
• The correlation analysis helps to developing the firm in evaluating the cost, rate, product of it sales on the base of other variables which are functionally correlated to it.
• It contributes to the economic performance that supports to recognizing the critically significant variables to an economist on which several variables depends on other commercial variable. The correlation analysis is most common method used in business learning that contains Spearman rank correlation, Auto correlation and Pearson product moment correlation.

Correlation Coefficient:

The correlation coefficients is a method used in statistics to measure in what way the relationship between the variables are strong. There are various types of correlation coefficient (Mishra and Nayak, 2018). They are Pearson’s R are also known as Pearson’s correlation. It is a correlation coefficient which is typically used in linear regression. If you are beginner in statistics, first it needs to study about Pearson coefficient.

In this, correlation coefficient formula is used to search in what way to strong a relationship among the data. This type of formula value returned between 1 and -1.  Here, 1 specifies a strong positive relationship, -1 specifies a strong negative relationship and a result of 0 specifies there is no relationship at all (Nayak and Mishra, 2018).

Each statement of correlation is given by the equation in which is based on “0” round coefficient. In case of the statement as “1” round coefficient and the equation in the form of “0” is given as,

       

From the above equation, the relationship between the round coefficient “1” and round coefficient “0” can be identified.  The frequency in the figure sharing illuminating the errors specifies that the above correlation is statistically effective. The below figure refers the histogram frequency which has the value from 0 to 35 and it will be increased by 5, and bin has the value of -1 to 1.1.  

In the statement of “2” round coefficient the equation in form of “0”round coefficient as,

From the above equation, the relationship between “2” round coefficient and “0” round coefficient can be identified.  The figure of the frequency sharing demonstrating the errors specifies that the above correlation equation is statistically effective.

The statement of “3” round coefficient equation in the form of “0” round coefficient is given below.        

From the above equation, the relationship between “3” round coefficient and “0” round coefficient can be identified. The figure of the frequency sharing shows the errors specifies that the above correlation is statistically effective.

The rolling machine is a machine designed by roll marijuana or another products. The previous sections shows the expressive statics to check the numerical variables.  It express the indentations of the organization method and Removable Partial Dentures records. The database is used for the upcoming research analysis. Each individual numerical range is suitable for the numerical controls. The interferences for roll machine indifference to adductive deduction and deductive reasoning (Optimum Thread Rolling Process That Improves SCC Resistance, 2001). The inferences is a reasoning method and is supplying the few evidence for the conclusion. This is a truth conclusion of an inductive argument. The argument is feasible established on the evidence. Inference is a complex for the roll machines. The roll machine get the numerous knowledge around the geometry. The machine measuring and machine tools create the full areas of modern manufacture. The machine requirement provides the controlled process, as a part of the geometric accurateness which is accomplished. The rolling process is essential to the roll grooves. In the roll grooves, the possible ranges needs to be understand and the numerical definitions needs to be identified. The roll machine solves the alleviating problems.  The frequency is increased when the roll changes in the rolling machine. The morphometric defect is occurred which increases the cost for the low product and delay the operations. And also, it increases the energy, resources, fuel and tool.

The rolling machine has following importance.  They are rolling capacity, full surface parallel to each other and produce the same diameter. The material is applied to reflect the improving rolls. The rolls need the thicker range of ends. The range of rolls depends upon the tolerance. The installed option is adjusted to vary the tolerances in the various machines. The parallelism affected or modified, when adjust the pinch pressure. The outside tolerance material does not harden during the multiple access (Wang and Wang, 2014). The machine capacity is equal. The volume is not more than the style. The bending machine or rolling machine is covered with the dissimilar metal sheet. There are different technology used in the roll bending machine such as pinching roll, two side roll and four roller machine. The most important item in the roll machine is the cone rolling device and roll surface. The laser or plasma and harder materials cutting techniques needs the outer hard roll surface on the rolling tool. The long-lasting protection provides over the rolling surface.

The roll surface results in crazing and penetrating of the shallow when the hardness is more than 60. The cone rolling device allows the conical shape on the roll machine. The less often is requested when provisioning the lateral material and overhead. The overhead has supported the stop light resources from the crumbling. A side also supports the stop light resources from the redressing. Few machine have extend through the machine frame. The pipe is fitted on the stub shafts. But, it is not suitable for the roll angle. When the screw is revolved, then the angle is created. The plate roll does not have lateral material, outboard and adjustable guide to prevent this rotations (Wusatowski, n.d.). There are two types of bending in this rolling machine such as section roll and angle roll. The new roll machine is equipped with safety device. There are many safety device in the roll machine such as low voltage control circuitry, emergency stop buttons and safety trip wires. The installation of device should be proper for safe operations. If any problem occurs, then it should be informed to the respective person. The tonnage is reduced when the operator is stance the bottom rolls. The less tonnage requires the wider die and needs to bend the material with narrow die.  The operator needs to get the roll on geometry machine variable. The thinner roll material and the proximity close to top of the roll. It also creates the thinner roll in the diameter ratios. It modifies an angle and create the perfect machine for rolling cone. The upper cone applied in the incredible pressure. The many geometry rollers and customers are pressing the rolls. The geometry variable plate roller get the competitive edge from the JMT. The JMT has the perfect line of metal of the rolling machine with the angle rolls, profile tube and plate rolls. The profile tube benders provide the reliable performance.

Conclusion

The novel approach for the Roll pass design problems is embraced by the research methodology. The rolling pass morphometry is obtained by the brand-new universal method. The morphometry means geometry and dimension of the material which is rolled on the rolling machine. The series of grooves are designed in the roll pass design (RPD). To obtain the desired geometry, dimension, and mechanical attributes, the material which is rolled is deformed. The Roll pass design analysis framework is provided by this new approach in morphometry (YU, WANG and QU, 2010). This also leads to actualize the hot rolling process which is sustainable. For improving the amount of actual roll pass design observations, the followings are employed. They are advance mathematical methods and complex computing packages. The computers used nowadays are having more capacity. Because of its processing capacity, the human perception’s limitations are overcome.

To explore the high dimension patterns, the interfaces of human – computer and the technique of data mining is used. They are efficient and adaptable to explore those patterns.  The summarization of the methodology which is presented above in the report is given in the following lines: how many separate group of people came under the same search, the partial but the different information are given by each and every people. From the information, the different patterns and probed directions are extracted which points the Holy Grail’s exact location. The Roll Pass Design algorithms defined by this recent research (ZHANG, 2009). The defined Roll Pass Design algorithm is used in finishing passes. The circular cross section of lengthy products are rolled. In this research, the different algorithms and principles are developed. These are extendible. It is also suitable for broader spectrums. The long products which has high symmetry comes under broader spectrum. The findings of this research will potentially help the further research in this topic. The solution of the research including the instructions for design will enhance the machined geometry.

By improving the machined geometry, the finishing round grooves and leading ovals are done perfectly (ZHAO, 2009). The tool offset wear is allowed by the newly developed machined geometry. This will lead to enhance the process parameters’ entire range. The improved design of finishing passes in the rolling process is enhanced the rolling process of round products.  The ANOVA test is conducted to find the difference between two or more variables in the designing of roll pass design. The correlation analysis is done. By creating Roll Pass Design, the following parameters are obtained. They are high yield, increased productivity, high reliability and cost. The methodology used in Roll pass design is explained and the frame work algorithm is also explained briefly in this paper. The features of structured database is analyzed. The descriptive statistics are presented and the results of the descriptive statistics are obtained and tabulated. The radar graphs are drawn and the screenshot are attached (ZHOU, 2007). The significance and interference of the rolling machines in the mills are explained.

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