Question

Computer Numerical Machines (CNC machines) are advanced machines consisting of different types(turning and milling) that are utilized for part cutting and design. They categorize under subtractive manufacturing, while 3d printers and scanners branch from additive manufacturing. For the process of cutting any certain part to achieve a desired shape, the first step begins with design, to finally reach the manufacturing procedure. Accordingly, you are required to choose a part (the part does not need to be related to engineering, any part that can be manufactured using the machines you have learnt throughout this course is acceptable), and consider yourself the manufacturer of this part. You will understand what your part is and its functionality (how it works, its dimensions, which machines can be used to manufacture it...etc). • Hint: Your part can be simple, yet a functional part, for the aim of this project is to be able identify the correct machine usage for its manufacturing and procedure • The machines to be used in this project: Tuming Machine, Milling Machine, Bandsaw Machines, 3d Printer, Engine Lathe, Drilling Machine Any part that can be manufactured by the usage of one of these machines is acceptable Examples: Gears, Shafts.etc After having full knowledge about your part, clearly answer the following questions 1. Give a clear and concise definition of your Project. (What is your part? How it works? Its design) Describe Project Steps and Objective. 2. Describe your Mechanical Design in General. Show Pictures and describe the function and use of each part (if you part consists of several parts to have a final assembly, state each part and its design) 3. Write step by step instructions for the maintenance of your product

Answer 1

Title - Shaft Design

Solution : 1. Functional Part Shaft (Transmission Shaft) Function The shaft is a structural member which rotates and transmit power and motion. materials used Materials must possess following mentioned properties : :) High strength ii) Good Machinability ii) High wear Resistant iv) Good Heat Treatment property Carbon steel are preferred materials due to possessing desired properties at low cost. Manufacturing steps of shafts - Step 1: Using Turning Lathe machine a huge billet of turned to desired shaft diameter material is Step 2: Using Bandsaw Machines the shaft is trimmed along its length for the required dimensions step 3 : Use of Milling Machine is done to carve out on the surface of the shaft. the key way Step 4: Drilling machine is used to drill small oil holes for the lubrication purpose. stop 5: Using polish paper machine, polishing of the shaft material is done.

2 Objective of the Project - The objective is to get acquinted & known about different manufacturing methods and stops carried out for the manufacturing of functional parts. The purpose of each machine is known here with its function & even get known to the materia selection according to the properties available. 2. Design of shaft is done at there stages i) Design for Bending: Using the flexural formula, the shaft. is designed for bending strength such that it doesn't fail due to the Bending moments acting on the shaft formula of flexural. oben E Mmax INA y R where, Mmax Maximum Bending stress INA Moment of Inertia about Neutral Anis oben Bending stress y Distance of neutral anis from edge. Youngs Modulus of Elasticity - Radius of Curvature E R

(1) Design for Torsion : Using the Torsion formula, the shaft is designed for Torques transmitted such that it doesn't fail to the shear stresses acting upon the shaft due to Torsion. Formula for Torsion : ?max T J GO L R where, T Torque Polar Moment of Inertia J Emax = Maximum shear stress R Radius of shaft G shear Modulus of Rigidity Angle of twist L = Length of shaft no ii) Design for stress concentration: It is ensured that sudden thick edges must be present in the shaft that stress concentration. cause

4 3. Maintenance of Transmission shafts 0 Inspect for wear. 2 ② Timely lubrication. ③ Polishing after a certain due period. ① Paint onide layer for anti-corrosive property 4 S Recheck the key way and slot dimensions after a a certain period.

Summary - Manufacturing methods such as turning, drilling, milling are performed on the shaft. Material used are grades of steel having carbon contents.