Machine Design

Sizing the elements every machine is built from. Apply mechanics and strength of materials to real machine elements. Learn to design shafts, gears, bearings, springs, couplings, brakes, clutches and fasteners — with the standard formulas, catalogue-selection methods, safety factors and failure modes engineers use every day.

• Shafts — Shafts transmit torque and carry gears, pulleys and bearings. Learn loads on shafts, combined bending and torsion, equivalent stress theories, fatigue-based design (DE-Goodman), keyways and shoulders, deflection and critical speed.
• Gears — Gears transmit motion and torque with a fixed ratio. Learn spur, helical, bevel and worm gears, module and pitch geometry, gear ratios and trains, tooth forces, Lewis bending and AGMA/ISO contact stress, and gear materials.
• Bearings — Bearings support rotating shafts with low friction. Learn rolling-element (ball, roller) and plain (journal) bearings, load ratings, L10 life, equivalent dynamic load, selection from catalogues, lubrication, mounting and failure modes.
• Springs — Springs store energy and provide controlled force. Learn helical compression and extension springs, spring rate, shear stress with the Wahl factor, spring index, buckling and surge, springs in series/parallel, and leaf and torsion springs.
• Couplings — Couplings join two shafts to transmit torque. Learn rigid (flange, sleeve) and flexible couplings (jaw, disc, gear, bellows, Oldham, universal joints), misalignment, keys and bolt sizing, service factors and selection.
• Brakes — Brakes convert kinetic energy into heat by friction. Learn disc, drum, band and block brakes, braking torque, energy and temperature rise, self-energising action, friction materials, and vehicle braking distances.
• Clutches — Clutches connect and disconnect shafts while running. Learn plate clutches (single and multi-plate), uniform-pressure vs uniform-wear theory, cone and centrifugal clutches, engagement energy, and one-way and dog clutches.
• Fasteners — Bolts, screws and nuts hold machines together. Learn thread terminology, property classes, tensile stress area, preload and tightening torque, joint stiffness and load sharing, bolt groups in shear, and locking methods.