MANUFACTURING PROCESS CASE STUDY PRESENTATION

ABOUT VALVES

1. Valves A Case Study

2. What is a Valve? A valve is a device that opens, closes, or partially obstructs numerous passages to regulate, direct, or control the flow of a fluid (gases, liquids, fluidized solids, or slurries). They are used for a variety of purposes, including irrigation, industrial process control, and household applications.

3. Functioning of Valves Water system management Control the pressure Backflow should be checked Control the flow of the water

4. Manufacturing Valves by Casting

5. Lost Wax Casting Cast valve components such as carbon steel, stainless steel and other cast alloys can be made through lost wax casting. For valve components lost wax casting is a precision casting technology that allows us to obtain acceptable dimensions and tolerances as well as a smooth surface. Lost Foam Casting This casting process is better suited for producing precise cast iron valve components with high surface quality and sizes such as neat shape while casting that requires no or minimal machining.

6. Managing Shrinkage To reduce solidification shrinkage porosity, metal intensification pressures are maintained throughout the solidification process. The tiny gates used in the traditional die casting on the other hand freeze fast forming a barrier that prevents pressurization within the die cavity.

7. Manufacturing Valves by Forging Forged valves are made using a process called forging, which involves shaping metals and alloys while they are still solid. Forging the walls valves has numerous advantages for industries. Forged valves are formed from a single solid piece, reworking the material to get the desired shape and size requires little effort . Forged walls are known for the strength making that is excellent high pressure and high temperature applications . The grain structure also becomes increasingly refined during this process .

8. Detailed Method for Forged Valves Cutting & Forging: Following the selection of the material, it must be cut into desired lengths and widths. The next step is to forge each component by partly heating it to a specific temperature . Trimming: Trimming is the next stage. This is when the burr(rough edge) or extra material is removed. The body is then flashed to give it the proper valve shape.

9. Sandblasting: Sandblasting makes the valves smooth and clean. The size of the sand used depends on the customer requirement or standards. The valves are initially sorted out to remove the defective ones. Machining: Depending upon the design and the needs of the client, machining can improve the sizes and shape of the threads, holes and other small components . Detailed Method for Forged Valves

10. Materials & Allowances Carbon steel(WCA,WCB), stainless steel(SS304,SS316), grey iron(HT200,HT250) and ductile iron(QT400-18,QT500-7) are the most common materials generally used. In the case of carbon steel pipelines and valves, a standard quantity of 3 mm corrosion tolerance is commonly recommended.

11. Finished product Reuse machining components like NC Lathe, CNC, drilling machine, etc. to offer completed valve casting components for various machining requirements.
Magnetic particle testing and ultrasonic testing are required after casting for large diameter valve casting components to eliminate all the possible casting flaws .

12. Thanks