Description:DETAILED DESCRIPTION OF THE INVENTION
The system and methodology for simulating the metal solidification process and associated sand testing equipment are created in a way that provides complete information and a deep understanding of the process and associated machinery from the ground up. The method inculcates technical skills in a thorough way to build and fabricate their own metal components and execute troubleshoots with a comparable assembly if the necessity arises. The System offers detailed working of the parts of cyber physical units and other apparatus.
The design system (100) to simulate sand testing equipment and metal solidification process reproduces in the simulation system the precise functionality of the physical real-time operation and realisation of the specified commands. This design system (100) serves as a conduit between the processing information on the server side (103) and the users on the client side (102). Due to the interactive user interface (101) to the cyber-physical units that imitate every function by connecting to the closest server for immediate response to the user, users can work on their computer system from anywhere in the world and have an immersive learning experience. The server-side processor (105) processor and stores it in the server-side storage memory (106). Client-side processor (108), which manages information received at the client end, then executes client-side applications (109). This technique can be used to train masses of users (104).
The invented design system (100), which focuses on imparting in-depth knowledge and educating inquisitive minds. This system is structured in a very orderly and stepwise manner that emphasises the all-around learning process and proceeds in a sequential process flow. Utilizing materials created and tested in other virtual units of the developed system is a part of the invented system. These units are:

Sand fraction analyser unit (200): This unit determines the clay content present in base sand sample (206). Clay is extremely fine-grained natural soil material (with < 2 microns size) containing clay minerals (aluminium silicate), which acts as binder material in sand sample used further. This sand contains 2 – 50% clay. When clay is mixed with water it imparts strength, plasticity, and good binding strength. If clay content is increased in sand, it will increase its strength but decrease its penetrability. There are two ingredients in clay: Fine silt and true clay. Clay imparts binding strength whereas fine silt has no effect on binding strength. Unlike sand, clay particles have flake like structure meaning that their surface area is much larger than thickness and these particles have great ability to hold/absorb moisture. Base sand brought directly from any source contains some amount of clay in it, but that amount may not be sufficient for making sand chamber. Therefore, it becomes essential to quantify the amount of clay it contains. After performing the analysis on base sand, one would be able to determine the amount of clay to be added/removed to establish a proper balance. When clay particles suspended in water react with sodium hydroxide, precipitation is formed which can be weighed using weighing scale. Following are the steps involved in the simulation to analyse the sand fraction in a clay sample:
Mixing 50g of base sand sample (206) with 475 ml of pure water is combined with 25 ml of NaOH solution (202).
Take this mixture in a glass jar and put it in and then turn on a mechanical stirrer (204).
Setting the timer for about 5 minutes, mixing water up to 6-inch level, again stirring for 2 minutes to now allow sand particles to settle down at the bottom.
Clicking on the siphon to take 5 inches of unclean water from the glass jar.
When the water in the glass jar is clear, repeat the process 3–4 times.
Removing the wet sand from the glass jar, placing it on a tray, and placing it in a heating unit (205) set to 110°C to dry it out and weigh it using the electronic weighing machine (201). Calculate the amount of clay in the sand using the formula below.
Percentage clay content is = (w_1-w_2)/50×100
Sand grain-size testing unit (300): This unit assigns a number which is the measure of the fineness of a given sand sample (206). It measures the sand sample's average grain size. Parameters affecting the number of a sand sample are metal type, temperature of pouring, product mixture of metal part and required surface finish. After determining an optimal value for the number, maintenance of consistency of the grain structure is the critical portion to be achieved. Following are the indication if the determined number is:
• High = Fine Sand = Low penetrability leading to gas defects
• Low = Coarse sand = metal penetration, a rough finish on the surface, burn-in, and burn-on
Since the number just represents an average of fineness, sands with different distributions can have the numbers. The vibrating machinery (301) involved in this unit is used for the size-based separation of different particles of the sand sample. The separation is performed by passing the sand sample (206) through a series of sieves by the phenomenon of agitation. This vibrating machinery (301) can be of several types based on the strainer distribution and the level of automation.
Average grain-size number, GFN = Q/P
where , Q = sum of product of sand percentage retained in strainers and specific multiplier
P = sum of the sand retention percentage in sieves
Following are the steps involved in performing the simulation of Sand grain-size testing unit:
Choosing the amount of sand sample (206) to be tested
Weighing the amount of sand sample (206) using the electronic weighing machine (201)
Arranging the strainers in increasing order of their number (bottom to top)
Transferring the sand sample (206) to the topmost strainer
Clamping the strainers with the sand sample inside
Switching on the vibrating machinery (301) and letting it agitate for 10-15 minutes, by observing the time suing a electronic timekeeper (302).
Switching off and unclamping the apparatus
Weighing the sand samples divided into strainers.
Calculating the percentage retained for every portion.
Calculating the product by multiplying the retained percentage in every strainer with the multiplying factor
Calculating cumulative values for percentage retained and product. Divide them to obtain average grain-size number.
For sand penetrability testing unit (400): This unit determines the numeric value of the amount of penetrability in the green sand, core sand and raw sand. The physical feature of sand that makes it easily permeable to gases is called sand's penetrability. It can be understood that when the molten metal is put into the sand chamber, it comes into touch with the wet sand and produces steam or water vapour. Additionally, molten metal contains some dissolved gases that emerge as the metal begins to freeze. So, gas holes or pores will form in the metal portion if the gases and water vapour generated by the molten metal and sand do not find a way to completely escape via the chamber. To allow the gases and water vapour to escape, the sand must be suitably porous. To allow the gases and water vapour to escape, the sand must be suitably porous. The term "penetrability" refers to this characteristic of sand. Penetrability is described by the American Foundry Men Society (AFS) as "the number obtained by passing 2000 cc of air through a standard specimen at a pressure of 10 gm/cm2 for a particular time in minutes.". One of the most crucial characteristics impacting sand chamber characteristics is penetrability, which depends on a few elements including grain size, grain shape, grain distribution, binder concentration, moisture content, and degree of compaction. One of the most crucial characteristics impacting sand chamber characteristics is penetrability, which depends on several elements including grain size, grain shape, grain distribution, binder concentration, moisture content, and degree of compaction. Sand's penetrability is quantified by a value known as the penetrability number and the penetrability is calculated by the following equation:
PN = VH/PAt
where, V = Airflow rate through the test object in volume, 2000cc
H = Height = 50.8 mm (standard value)
P = Manometer reading of pressure in gm/cm2
A = Area of the specimen = (pd^2)/4 where d = 50.8 mm (standard value)
t = minutes it took for 2000 cc of air to travel through the sand sample.
Following are the steps involved in the simulation of this unit:
Selecting the specific sand sample.
Filling sand into the specimen tube (402) and ram thrice using sand rammer (401).
Click on the 'O-P-D' valve knob to set it at 'D' position of the penetrability meter (403).
Pouring the water up to the ‘W' mark into the water tank.
Inserting air tank into water tank carefully.
Slowly lifting the air tank to place it at 0 mark.
Clicking on the 'O-P-D' valve to set it at ‘O’ position.
Noting down the initial reading of the manometer.
Clicking on the standard specimen to place it along with the tube in the inverted position on the rubber boss.
Clicking on the 'O-P-D' valve knob to put the valve on ‘P’ position.
Simultaneously starting the electronic timekeeper (302) to note the time required to pass 2000 cc of air through the specimen.
Reading the height of the water column in the manometer tube (i.e., noting down the initial reading of the manometer)
Calculating the penetrability number by using the formula given.
Core fabrication unit (500): Sand pieces called "cores" are used to create hollow areas in metal parts when they solidify. It is positioned in a chamber of sand so that when molten metal is poured into the chamber, that area of the cavity will remain empty, not being filled with molten metal. Therefore, the metal section will have a hollow piece when the chamber is shattered, and the metal parts are removed. The materials used to create the cores include pitch and resin binders, water soluble binders (2 to 4 percent by weight), and binders made of oil (1-3 percent by weight) (1-35 by weight). The binder is made of organic material. Clay, such as Kaolinite, Ball Clay, Fire Clay, Limonite, Fuller's Earth, and Bentonite, serves as a binder. Dextrin, molasses, cereal binders, linseed oil, and resins like phenol formaldehyde and urea formaldehyde are among the binders that fall under the organic category. For manufacturing cores, organic binders are typically employed. The bentonite kind of clay is the most often used of all the binders mentioned above. However, without moisture in the sands of chambers and cores, this clay cannot by itself create connections between sand grains. Following are the equipment used in this unit and their function:
• 'Ladle' (501) to pour the binder into the sand. Core sand prepared.
• 'Core Sand' to transfer it into the core-box (503).
• 'Rammer' (504) to ram the core sand into the core-box (503).
• 'Pin' (505) to make a hole into the core.
• 'Cylinder' (506) to pump carbon dioxide into the core.
• 'Rammer' (504) to ram the core-box to loosen the core. Core (507) prepared.
Core hardness testing apparatus (600): Core hardness is the numeric measure of bonding and hardness of the cores. The unit determines a numerical value to the core sample (507) after being tested with the unit. Core sand hardness depends upon- degree of ramming, percentage of sand and percentage of binder. The unit uses a scratch-type tester (601) which consists of a carbide tipped plough. This contains a dial indicator in which the numeric value ranges between 0 and 100. Instrument should be kept clean and away from dust, ensuring that all sticking sand is removed from the instrument before and after every test. Setting and calibration of the testers should not be tampered with. Following are the steps involved in the simulation of core hardness testing apparatus:
Choosing the core (507) of which the core hardness is to be checked.
Clicking on scratch-type tester (601) to scratch the surface of the core.
Scratching the surface of the core (507).
Calculating and inputting the average of the three values to check.
Core strength testing apparatus (700): This apparatus determines the compression, shear, and tensile strengths of the core. Thus, this unit is segregated into three sections:
Compression strength test - Periodically, this test must be carried out. Silica sand, clay, water, and more specialised components make up sand. Sand that is moist is given the requisite binding strength by clay. The adhesiveness or bonding strength of various bonding materials in green sand is evaluated by a compression test. The strongest that a combination can become when it is in its best form is called the green compressive strength of foundry sand. The processes involved in simulating this testing are as follows:
Sand and clay were weighed in quantities, and they were dry mixed in a mixer for three minutes.
Adjusting the sand's weight to obtain a standard specimen.
Putting the standard specimen between shackles that are fixed in the sand testing apparatus after removing it with a stripper.
Activating the ram by turning the testing machine's handle. As a result, hydraulic pressure is constantly supplied until the specimen rips.
Reading the gauge's compression strength and recording it.
Carrying out the experiment in the two circumstances and tabulating the outcome.
Tensile strength test - A core is a mound of compacted sand with a predetermined shape. A core is placed in the sand chamber when a hollow casting is needed, or cores are used to build a chamber when a complex contour is needed. Making cores involves using core boxes. Either one piece or two pieces can be constructed. Their classification is typically based on the core's design or production process. The split core box, which comes in two halves and can be linked together with dowels to create the entire cavity for creating the core, is particularly popular. The binder is used to give the sand strength and cohesion so that it can maintain its shape after the core has been rammed. The core is positioned inside the sand chamber cavity during the metal solidification process, and molten metal is then poured into it. The molten metal starts to compress on both the inner and outer radii as it starts to cool. The inner radius will compress, pulling the core sand outward and creating a tensile load all the way around the core as a result. Therefore, it is crucial to understand the tensile strength of core sand. The procedures that were used to simulate the cores being tested under tensile are as follows:
mixing base sand and binder in the appropriate ratios.
Putting the core box together and adding the mixture to it.
placing the core box beneath the sand rammer and three times pounding the sand
Gently tap the core box from the sides with a piece of wood. leaving the ramming core on a flat metal plate after removing the core box.
Baking the sample (which is on a plate) in an oven for about 30 minutes at a temperature between 150O and 200O C. (When core oil is used as a binder)
If sodium silicate is used as the binder, pass CO2 gas for five seconds. Instantaneously becoming harder, the core is now ready for usage.
Inserting the specimen in the tension shackles after attaching the tension shackles to the sand testing machine
Spinning the testing machine's hand wheel to progressively apply the load. recording the readings as soon as the specimen fails.
Tabulate the readings after repeating the process for each different binder %.
Shear strength test - Sand particles' capacity to withstand shear force and adhere to one another is known as shear strength. Sand in the sand chamber could collapse or be partially destroyed during handling if there is insufficient shear strength. While molten metal is flowing through the chamber cavity, the core and cavity could both sustain damage. The sand needs to be strong enough to allow the chamber to take on the desired shape and keep it even after the hot metal is poured into the chamber cavity. When a specimen is sheared, the rupture happens parallel to the specimen's axis. The procedures for evaluating the shear strength of the core specimen are as follows:
Using foundry sand that has been measured (mixture of sand, clay & water as specified).
Placing the sand mixture in the tube and three times using a sand rammer to ram it.
Shackles to the universal sand testing device
Using a stripper to aid, remove the specimen from the tube and load it into the apparatus.
The universal sand testing machine's handle is constantly rotated to provide hydraulic pressure until the specimen ruptures.
Take a straight reading of the shear strength from the scale and total the results.
Archetype fabrication unit (800): In the hands of foundry men, an archetype serves as a forming tool. The metal part must be produced as a model or replica. An archetype exactly resembles the casting to be made, excluding the different concessions. An archetype can be defined as a model or form that is surrounded by sand to create a chamber cavity into which molten metal can be poured to create a metal object. An archetype sets up a cavity to create a metal component. If the metal solidification process calls for a core that must be hollow, it may have projections known as core prints. It is possible that the archetype includes the runner, gates, and risers (used for introducing and feeding molten metal to the cavity). It can assist in setting up locating points on the sand chamber and consequently on the metal component to check the dimensions. The chamber's dividing line and parting surfaces are established by the archetype. Archetypes that are well-made, polished, and have smooth surfaces minimise flaws. The overall cost of making metal parts is reduced by properly built archetypes. In addition to hand tools, a modern pattern maker's shop requires certain power-driven equipment. These tools aid the archetype builder in boosting output, enhancing accuracy, and preserving consistency. An archetype builder uses the tools below for a variety of purposes in order to easily and comfortably accomplish many more operations: Steel rule, Shrinkage rule, Calliper, Divider, marking gauge, Trammels, Try square, T-bevel, and Combination square are among the measuring, making, and layout tools; Hand vice, Archetype maker's vice, bar clamp, C-clamp, hand screw, and pinch dog are clamping tools used to hold wooden parts together for joining, etc.; Sawing equipment includes the following: a coping saw, a bow saw, a compass saw, a rip saw, a crosscut saw, a panel saw, a back saw, a dovetail saw, and a mitre saw with a mitre box.
When compared to a normal casting, an archetype is always larger in size because it includes allowances for both mechanical and metallurgical factors. For instance, a shrinkage allowance results from a metallurgical phenomenon, while allowances for machining, draught, and other factors are included on patterns for mechanical reasons. Archetype allowances come in a variety of forms, including (a) shrinkage or contraction allowance, (b) machining or finishing allowance, (c) draught or topping allowance, (d) distortion or camber allowance, and (e) shake or rapping allowance. When compared to a normal metal part, an archetype is always larger in size because it includes allowances for both mechanical and metallurgical factors. For instance, a shrinkage allowance results from a metallurgical phenomenon, while allowances for machining, draught, and other factors are included on patterns for mechanical reasons. Archetype allowances come in a variety of forms, including (a) shrinkage or contraction allowance, (b) machining or finishing allowance, (c) draught or topping allowance, (d) distortion or camber allowance, and (e) shake or rapping allowance. Following is the procedure of the simulation to fabricate an archetype:
Making a rough sketch of the archetype (802) to be made and then according to dimension, making a drawing.
Deciding whether the archetype is to be made in stages or with single block.
Taking a wooden piece, measuring the dimensions, marking the circle with the dimensions using a ruler (801) and mortise marking gauge (803)
Cutting the cylindrical pieces of different diameter and different height, using a toothed cutting tool (804).
Three cylindrical archetypes would be obtained with the help of adhesive glue them to make a single archetype.
To use them in metal solidification process, a hole for shaft will be made after the molten material is solidified.
Sand chamber hardness testing unit (900): Sand chamber hardness is the numeric measure of how hard the chamber has been rammed. Sand hardness depends upon- degree of ramming, percentage of sand and percentage of water. The apparatus is an indentation-type tester (902) which works in a comparable manner to Brinell hardness tester in which the depth of insertion of the indentation indicated the value in hundredth of a millimetre. The tester has a dial indicator ranging between 0 to 100. The indenter is mechanically a steel ball with a spring-loaded plunger. Following are the steps involved in the simulation of this unit:
Choosing the sand sample (206), of which the hardness is to be found.
Using 'Shovel' (502) to transfer the sand into the drag (901).
'Rammer' (504) rams the sand uniformly into the drag (901).
Clicking at the centre and four corners of the drag to calibrate five reading of the hardness as to how tightly the sand is packed inside the drag.
Metal solidification unit (1000): The use of sand chambers is the most common technique for producing metal components. Sand is rammed into a metallic or wooden flask to create sand chambers. This process is frequently referred to as metal solidification. Following the creation of the core (507) and archetype (1001), the cope and drag assembly (1004) is ready, and the sand sample is used to ram these components together. The multi-step method of creating a sand chamber consists of creating chambers with the necessary cavity in a substance suitable for pouring molten metal, such as sand. By surrounding the archetype with some easily generated aggregate material, like sand, the sand chamber is created. The chamber cavity is created when the archetype is removed, and metal is then added to complete the metal component. To acquire the metal part's desired size and shape, it is necessary. Sand is a popular building material for metal solidification chambers since it is a suitable refractory material for most metals. Melting is the process of preparing molten metal for the metal solidification process and changing solid metal into liquid metal in a furnace. After that, a ladle (1006) is used to transport the liquid metal into the sand chambers. Shakeout is the process of vibrating the chambers to remove the sand from the metal portion after the metal has set. Various kinds of furnaces are utilised during the procedure to melt the metal. The size of the metal component, the quantity to be produced, the rate of production, and the metal to be solidified may all affect the kind and size of the furnace. The following step considers how long it will take the casting to cool and solidify. In this stage, faults typically manifest themselves. To make room for the finished metal portion (1007), cleaning is the last step. The gating systems are taken out of the sand chambers during rough cleaning. Any remaining sand on the piece after it has been released from the sand chamber is removed during the initial finishing process. Trimming gets rid of any extra metal. The metal part's surface is cleaned in the last stages of finishing to give it a better aesthetic appeal. This unit performs the following steps:
Placement of the inverted archetype (1001) at the bottom of the inverted drag
Transfer of the sand sample into the drag with shovel (502)
Ram the sand into the drag and invert it (the pattern faces upward)
Sprinkling the parting sand (1005) over the drag
Fixing the cope on the drag with guide pins
Placing the sprue (1002) and the riser (1003) perpendicularly into the cope at the allotted positions
Filling the cope with the sand and ramming it
Removing riser (1003) and sprue (1002)
Removing the archetype (1001) by removing the guide pins
Damping a depression for pouring basin
Pouring the molten metal into the sprue (1002)
Displaying prepared metal part (1007) after solidification
Each unit of the invented system consists of the following salient features-
Aim: The purpose of the experiment the user is performing is the first thing the user needs to know. Therefore, the "Aim" of the module, which tells the user about what he/she is going to learn and provides him or her with an outline of what the module deals with, is the first page that appears.
Theory: Following the "Aim" of the experiment, the user is then made aware of the theoretical information connected to the module so that they can have enough background information and fundamental knowledge about each step they are going to take. Here, the user is taught how to use and navigate the Simulation System's user interface.
Pre-test: A pre-test is offered to users, aiding in the organisation of the learned theory. This test will therefore concentrate on the knowledge that users must have learned the crucial ideas. Multiple-choice questions are used to teach the material.
Procedure: Procedure provides instructions on how to carry out the module, as it is done in the workshop in real time. The procedure explains how to use the simulation system and comprehend its workings.
Simulation: The traditional learning pedagogy in educating the metal solidification process and other related sand testing leaves an unclear impression in the minds of the learners. A student’s brain better grasps the concepts that are taught with pictures, along with words, and not with pictures or words alone. Simulations provide pictorial, self-paced visualisations of the workflows in the invented units.
Post-Test: A post-test is administered to gauge the user's understanding and abilities after they have completed all the simulation's steps. This test provides feedback on the user's level of understanding as well as any areas that still need to be addressed. This "Post-Test" exercise also serves the purpose of comparing the results with the "Pre-Test" results to provide a clear picture of the user's current situation and the knowledge they have acquired in this brief period of time. This exercise serves to inspire the user to complete the remaining modules in the workshop and become an expert in the metal solidification process.
, Claims:We claim:
1. A design system (100) to be used in metal solidification process to produce metal parts, comprising of:
a sand fraction analyser unit (200),
a sand grain-size testing unit (300),
a sand penetrability testing unit (400),
a core fabrication unit (500),
a core hardness testing apparatus (600),
a core strength testing apparatus (700),
an archetype fabrication unit (800),
a sand chamber hardness testing unit (900), and
a metal solidification unit (1000).
2. Sand fraction analyser unit (200), as claimed in claim 1, consists of an electronic weight tester (201), 5% caustic soda solution (202), clay sample (203), clay washer apparatus (204) and heating unit (205), to compare weights of the clay sample and the sand sample (206) after the removal of water content.
3. Sand grain-size testing unit (300), as claimed in claim 1, comprises of a vibrating machinery (301) which contains strainers having different porosities, electronic timekeeper (302), and electronic weight tester (201), to measure the fineness of sand particles.
4. Sand penetrability testing unit (400), as claimed in claim 1, uses a sand ramming apparatus (401), specimen tube (402), penetrability analyser apparatus (403) and an electronic timekeeper (302), to check the penetrability of the rammed sand sample.
5. Core fabrication unit (500), as claimed in claim 1, incorporates a ladle containing binder (501), a shovel (502), a core fabrication box (503), a rammer (504), a needle-type penetrator (505) cylinder (506), containing carbon dioxide gas, to model the shape of the box and obtain the final core (507).
6. Core hardness testing apparatus (600), as claimed in claim 1, is used to scratch on the core (507) to obtain a numerical value that indicates hardness of the core.

7. Core strength testing apparatus (700), as claimed in claim 1, performs tensile strength testing, compression strength testing and shear strength testing on the core (507) by converting manual rotary motion into linear translation.
8. Archetype fabrication unit (800), as claimed in claim 1, consists of ruler (801), wood sample (802), mortise making gauge (803), and a toothed cutting tool (804), to fabricate an archetype from the marked dimensions.
9. Sand chamber hardness testing unit (900), as claimed in claim 1, incorporates sand sample (206), rammed into cope (901), a shovel (502), a rammer (504), indentation-type hardness tester (902) to obtain a numerical value indicating hardness of the sand chamber.
10. Metal solidification unit (1000), as claimed in claim 1, inclusive of the part archetype (1001), a wooden archetype (1002) with semi-hemisphere top, a down-tapered wooden archetype (1003), a cope and drag assembly (1004), separated by parting sand (1005) and a ladle containing molten metal (1006), to provide a metal part (1007) after solidification of molten metal.