Claims:WE CLAIM THAT

1. An autonomous device capable of measuring the strength and permeability of the shell developed in investment casting without human assistance to minimize human error which is involved in data acquisition and computation in measurement of shell permeability.
2. As claimed in Ckaim-1,the device can be controlled remotely using computing device to get a real time monitoring of the measurement of the shell permeability that helps to reduce continuous human monitoring.
3. As claimed in Claim -1, the device is equipped with sensors and microcontrollers to make the device autonomous which makes the device user friendly by reducing complex computation.
4. As claimed in Claim – 1, the device facilitates measurement with different fluids including pressurized air as well as argon as the use of different fluids is found to be more useful.
5. As claimed in Claim – 1 the device is made capable to address issues including undissolved ping ball, and duration of dissolution of ball that further affecting the results of permeability.
, Description:TITLE
A device to measure shell permeability during Investment Casting process.

FIELD OF THE INVENTION AND USE OF INVENTION

[0001] This invention relates to the field of electronic engineering more particularly to the domain of manufacturing engineering, a device to identify and measure the permeability of the shell prepared during the investment casting process.

[0002] Here, a system is designed with sensor assembly and microcontrollers to accurately measure the permeability of the shell to acquire the necessary input from sensors and to compute the value of shell permeability as per standard guidelines published by Investment Casting Institute (ICI). This device minimizes human errors involved in data acquisition and computation in measurement of shell permeability. This will help in measurement of accurate values of shell permeability.

PRIOR ART AND PROBLEM TO BE SOLVED

[0003] In the manufacture of ceramic shell molds by the precision casting process, a multi-layered ceramic shell is built up by repeatedly dipping a wax pattern cluster in a dip-coating slurry, draining, and sprinkling with a coarse stucco sand. Each individual coat is hardened prior applying the next coat. The ceramic shell molds are poured with liquid metal to produce precision castings. The ceramic shells, which are thin walled molds, are generally subjected to metallostatic pressures and gas pressures. Metallostatic pressures vary due to the evaluation of gases during the solidification and the lack of permeability of the shells. The strength of the shell under casting conditions relates to the ability of the shell system to retain the molten metal and maintain the dimensional integrity of the

cast part. If the shell is not permeable enough, the resulting casting will have no fill where air was trapped in the casting. So, a method to ensure the permeability of the shell is very important. But many of the industrial investment casting foundries in India are not equipped with measuring facilities for shell permeability. This is due to lack of awareness about relevant method of measurement as well as complexity involved in computation of values of permeability. The presently available instruments require human assistance to calibrate and compute and they are prone to human error.

[0004] This invention provides an instrument which has been equipped with sensors and microcontrollers to automatically measure and computes the permeability of the shell without any human interference. The device is comprised of microcontroller further connected with sensors including flow sensors and pressure sensor. This system acquires the necessary input from sensors and computes the value of shell permeability as per standard guidelines published by Investment Casting Institute (ICI). The measured value of shell permeability further assists in tuning relevant shell making parameters, and leads to better productivity of process by reduces the occurrence of defects in precision investment casting.

THE OBJECTIVES OF THE INVENTION:

[0005] Investment casting process is essentially used for producing metallic parts that is in turn combination of various sub-process including pattern making, shell making, melting & pouring and finishing process. Properties of the molds, specifically flexural strength, permeability, and physical structure, need to be monitored and used as references for optimizing the formulation. The strength of the shell under casting conditions relates to the ability of the shell system to retain the molten metal and maintain the dimensional integrity of the cast part. So, the measurement of the strength and permeability of the shells are necessary.

[0006] It has already been proposed where, the measurement of their bending strength either at room temperature or at casting temperatures is measured. The bending strength of the shell is measured on a universal sand-strength testing machine of hydraulic type. But the problem is that they require human assistance in computation and they are frequently prone to human error.

[0007] The principle objective of this invention is an autonomous device capable to measuring the strength and permeability of the shell developed in investment casting without human assistance to minimize human error involved in data acquisition and computation in measurement of shell permeability.

[0008] Another objective of this invention is that the device can be controlled remotely using computing device to get a real time monitoring of the measurement of the shell permeability. This helps to reduce continuous human monitoring.

[0009] The further objective of this invention is the possibility of quick and efficient measurement of the shell permeability using computational mechanism.

[0010] The further objective of this invention is the utilization of sensors and microcontrollers to make the device autonomous. This mechanism makes the device user friendly by reducing complex computation

[0011] The further objective of this invention is it addresses issues including undissolved ping ball, and duration of dissolution of ball that further affecting the results of permeability.
[0012] The further objective of the invention is that the device facilitates measurement with different fluids including pressurized air as well as argon. However guidelines published by ICI were mainly focused on Nitrogen. Use of different fluids is also found to be more useful.

SUMMARY OF THE INVENTION

[0013] The permeability of a shell is of high importance to the metal casting process. The shell must be capable of allowing gases to pass through with at least the same rate as molten metal enters the shell. If gases cannot exit the mold faster than it is filled, then air pressure increases with the shell. This build – up of pressure can result in incomplete mold filling, shell cracking and gas defects in castings. The majority of previous investigations was done for filters and compacted ceramics. Secondly the other machines and methods used are complex and require human assistance which at major times causes human errors. So here in this invention a device is made which is capable of identifying the permeability and strength of the shell using sensors and microcontrollers so a to reduce human interactions so as to reduce human errors while the computation occurs to obtain the permeability of the shell. The system is designed with the facility of remote controlling so as to obtain real time data of the measurement of the shell. This makes the working user friendly and less complex that the present device,

DETAILED DESCRIPTION OF THE INVENTION

[0014] While the present invention is described herein by way of example, using various embodiments and illustrative drawings, those skilled in the art will recognize that the invention is neither intended to be limited to the embodiment of drawing or drawings described nor designed to represent the scale of the various components. Further, some components that may form a part of the invention may not be illustrated with specific figures, for ease of illustration, and such omissions do not limit the embodiment outlined in any way. The drawings and detailed description of it are not intended to restrict the invention to the form disclosed, but on the contrary, the invention covers all modification/s, equivalents, and alternatives falling within the spirit and scope of the present invention as defined by the appended claims. The headings are used for organizational purposes only and are not meant to limit the scope of the description or the claims. As used throughout this specification, the worn "may" be used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning, must).

[0015] Further, the words "an" or "a" mean "at least one” and the worn “plurality” means one or more unless otherwise mentioned. Furthermore, the terminology and phraseology used herein is solely used for descriptive purposes and should not be construed as limiting in scope. Language such as "including," "comprising," "having," "containing," or "involving," and variations thereof, is intended to be broad and encompass the subject matter listed thereafter, equivalents and any additional subject matter not recited, and is not supposed to exclude any other additives, components, integers or steps. Likewise, the term "comprising" is considered synonymous with the terms "including" or "containing" for applicable legal purposes. Any discussion of documents acts, materials, devices, articles and the like are included in the specification solely to provide a context for the present invention.

[0016] In this disclosure, whenever an element or a group of elements is preceded with the transitional phrase "comprising", it is also understood that it contemplates the same element or group of elements with transitional phrases "consisting essentially of, "consisting", "selected from the group comprising”, "including", or "is" preceding the recitation of the element or group of elements and vice versa.

[0017] Before explaining at least one embodiment of the invention in detail, it is to be understood that the present invention is not limited in its application to the details outlined in the following description or exemplified by the examples. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for description and should not be regarded as limiting.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. Besides, the descriptions, materials, methods, and examples are illustrative only and not intended to be limiting. Methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention.

[0019] The present invention provides a device to automatically measure the shell permeability using sensors and microcontrollers and is capable to provide real time data to the computing device about the measurement reducing human interference and human errors with respect to the computation performed. This device also addresses issues including undissolved ping ball, and duration of dissolution of ball that further affecting the results of permeability.

[0020] The measurement of permeability is primarily based on Darcy’s law. It is given in equation (1).
?? = ?? ×?? ×?? ….………………..Equation (1)
??× ??
Where K = permeability of specimen, cm2; ?? = viscosity of gas (dyne
sec/cm2);
f = flow rate of gas(cm3/sec); t = thickness of sample (cm); P = pressure of gas (dyne/cm2);
A = inner surface area of ping pong ball (cm2)

[0021] The device is developed as per guidelines Investment Casting Institute (USA). However, measurement technique suggested ICI does require human intervention in acquiring of flow rate, pressure, as well as in computing values of permeability. The outline of the equipment is as per

as shown in the figure 1. Controlling unit is relatively critical part of the measurement device, and explained next.

[0022] Here in the device Various sensors including Flow Sensors with the flow range of -100 to 250 slm2, Accuracy of 2% with an Operating Pressure Range of 0.66 – 1.07 bar and Operating Temperature Range 10 to 50 0C with Interface I2C protocol is used along with pressure sensors with a pressure range of 1 to 10 bar, Sensitivity of 0.01 bar, operating current range of 4 mA to 20 mA and Operating temperature range of 40 to 125 degree Celsius and accuracy of 0.25%. It has NodeMCU with supply voltage of 5 V, memory of 128 KB and storage of 4 MB. The converter module is attached to the device with a switch mode power supply and an LED display on which a minimum of 16 characters can be displayed at least in 2 rows.

[0023] The flow sensor is bi-directional sensor, and is required to sense the flow of gas (Argon) in the range of -100 to 250 slm2. The pressure sensor is used to sense the pressure of Argon gas, and has working range of 1 bar to 10 bar. These sensors are further connected with microcontroller through Switch Mode Power Supply (SMPS). This microcontroller acquires data (at every two second) related to pressure as well as flow, and streamed to server through mqtt protocol. Values of acquired pressure and flow will be embedded in equation (1) for computation of permeability.

[0024] For the understanding purpose a sample of the shell can be created using a circular pipe of stainless steel (SS 321) for holding shell as well as allowing gases to pass through it. Specification of pipe has been selected with the geometric specifications consisting of Inner Diameter (ID)7.8mm, Outer Diameter (OD) 9.5 mm, Length of pipe 300 mm, Weight 72 gm abs and the Chemical composition of circular pipe is measured through hand held XRF, and are mentioned in Table 1.

[0025] Heat the one end of circular pipe to approximately 500C for fixing ping pong ball (Konex ball with OD=40 mm). Care should be taken that heated end of the pipe should not be inserted in ping pong ball more than 0.5 inch (figure 2).

[0026] Appropriately seal the joining surface between pipe and ball with industrial wax. Provide the shell coating over the ping pong ball, and allowed the coated shell to set. The sample (ping pong ball attached to circular pipe with coatings) is ready for further process.

[0027] Once appropriate number of coating has been provided, and ping pong ball need to be dissolved. Dissolution of ping pong ball requires great care as it highly affects the values of permeability. To dissolve ping pong ball, Fill the sample (figure 2) with 20 ml of Methyl Ethyl Ketone (MEK).

[0028] Vibrate the sample gently, and rotates clockwise as well as counter clockwise by hand so that entrapped air from the sample can be escaped. Again, fill the circular pipe with approximately 15 ml of MEK to dissolve ping pong ball. Change position of sample by 1800 for flowing out the MEK from it. Keep the sample in same position for nearly 10 minutes. Check the sample using endoscopy camera for complete dissolution of ball. In case the ball has not been completely dissolved, tilt the sample for nearly 450, and allow the dissolved ball to flow out through pipe. Keep the sample in the same position for nearly 24 hours for drying.

[0029] Once the sample is prepared it can be tested in the permeability measurement device as illustrated in Figure 4. As shown the device consists of the flow sensors and the pressure sensors attached with a controlling unit and the sample created can be attached at one end and the gas cylinder can provide the pressure to test the permeability of the sample.

[0030] Here for the working of the system Set the gas (Argon) supply pressure of 3 psi in regulator attached to gas cylinder. Enter the relevant information in controlling unit like the thickness of shell and others. Initiate the test, and allow the system to stabilize. Result of permeability will be displayed at an interval of every 5 second. This result can also be streamed to smart device through smart application.

[0031] The computing device that may implement the techniques for data gathering and recovery, however, will readily appreciate that the techniques disclosed herein may be implemented in other computing devices, systems, and environments. In one embodiment, the data collection device may be implemented with the computing device. The sensor node may be implemented with the computing device is only one example of a computing device and is not intended to suggest any limitation as to the scope of use or functionality of the computer and network architectures.

[0032] Methods and systems in accordance with exemplary embodiments of the present invention can take the form of an entire hardware embodiment, an entire software embodiment or an embodiment containing both hardware and software elements. In a preferred embodiment, the invention is implemented in software, which includes but is not limited to firmware, resident software and microcode. In addition, exemplary methods and systems can take the form of a computer program product accessible from a computer-usable or computer-readable medium providing program code for use by or in connection with a computer, logical processing unit or any instruction execution system. For the purposes of this description, a computer-usable or computer-readable medium can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. Suitable computer-usable or computer readable mediums include, but are not limited to, electronic, magnetic, optical,

electromagnetic, infrared, or semiconductor systems (or apparatuses or devices) or propagation mediums. Examples of a computer-readable medium include a semiconductor or solid-state memory, magnetic tape, a removable computer diskette, a random-access memory (RAM), a read- only memory (ROM), a rigid magnetic disk and an optical disk. Current examples of optical disks include compact disk-read only memory (CD- ROM), compact disk-read/write (CD-R/W) and DVD.

[0033] In one embodiment, the present invention is directed to a machine- readable or computer-readable medium containing a machine-executable or computer-executable code that when read by a machine or computer causes the machine or computer to perform a method to detect malicious behavior in a mobile ad-hoc network in accordance with exemplary embodiments of the present invention and to the computer-executable code itself. The machine-readable or computer-readable code can be any type of code or language capable of being read and executed by the machine or computer and can be expressed in any suitable language or syntax known and available in the art including machine languages, assembler languages, higher level languages, object-oriented languages and scripting languages. The computer-executable code can be stored on any suitable storage medium or database, including databases disposed within, in communication with and accessible by computer networks utilized by systems in accordance with the present invention and can be executed on any suitable hardware platform as are known and available in the art including the control systems used to control the presentations of the present invention.

[0034] While there has been described and illustrated an architecture for multi- domain wireless mobile ad hoc network information dissemination and several modifications and variations thereof, it will be apparent to those skilled in the art that further modifications and variations are possible

without deviating from the teachings and broad principles of the invention which shall be limited solely by the scope of the claims appended hereto.

FIGURE DESCRIPTION

[0035] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate an exemplary embodiment and, together with the description, explain the disclosed embodiment. In the figures, the left and rightmost digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of the system and methods of an embodiment of the present subject matter are now described, by way of example only, and concerning the accompanying figures, in which:

[0036] Figure – 1 illustrates the permeability Measurement Equipment consisting of flow sensor (01), Pressure sensor (02), Controlling unit (03) and Led Display(04).

[0037] Figure – 2 illustrates the sample of the Shell (05) which is attached to a pipe(06).

[0038] Figure – 3 shows the arrangement of the sample (05) of shell in the permeability measurement equipment consisting of a gas cylinder (08) and an regulator(07) attached in addition to the system.

[0039] Table – 1 with the Chemical composition of circular pipe.