Question:

TT Pr TC ——— 1. (a) What is the visual evidence of gear teeth failure by bending and surtuce fatigue? 6) Write a short noe on Mackee's curve and also dein the bearing modulus. (© Draw the flowchart used to evaluate the performance characteristics of hydrodynamic journal bearing by using the ZNP method (d) How do you design a flywheel for an 1.C. engine and steam engine? ©) Why piston ini located aor above the middle ofthe sir length? asi) 2. (a) The following data is given for 360° hydrodynamic bearing: Vd 205; Journal diameter = 100 mon; Journal Speod = 1500 rpm; ‘niin oi lm thickness = 1 microns: Grade of he lubricant SAE 0 and operating lmperature = S0°C; Fit between journal and bearing = HTE?, specific gravity of the lubricant ~ 0.86; specific beat of the ubricant = 2.09 KYKg°C. Calculate (i) Load carying capacity: (i) Coefficient of fiction (i) power los in friction: 1) total lubricant flow at; nd () Side leskage. © (6) Figure 1 shows layout drawing giving details of a dive toa rotary cement il, draw a ree body diagram for this layout. Also, using the data given in Fig, calculate (i) Torgue to tum the kiln, (i) Electric ‘motor poser, (if) Worm gearbox rai. (i) tangential force on the worm if th pitch cic diameter of the worm i 100mm. © KN GEAR ANG See KILN BEARING = \V) S——— Vol He012 SRAM Holy scams Eo mn Roy Kin Hallo = WEIGHT » 2¢ Tonnes gd) HT = wrens EE nm '; GEAR wa 60%, GE HOE GOK WT Tw START Eng § PEAR (GEAR BOX N-85%) WORM |] "FLENBLE ELECTRIC MOTOR, Susie 600 RPM. eS FIGURE 1: DRIVE FOR A ROTARY KILN 3. (8) Select and design a stabi type of gear for the following input data: power 60 hp pinion runs at 6000 pm, speed ato is 3, and two parle sats ao (5) The following data s given for the piston of four-stroke diesel engine: Cylinder bore = 250 mu; Material of piston rings = Grey cas iron; Allowable tensile stress = 100 N/m’, Allowable radial pressure on cylinder wal = 003 MPa; Thickness of piston head = 42 my Number of piston rings = 4. Calculate the radial width of the piston tings and axial thickness ofthe piston rings. @ 4. Select a suitable ball being which i 10 operate at 1500 rpm, and is acted upon by 8000 N radial load and S000 N thrust load. The inner ving rotates he load is stcady nd the service i continuous, The shaft ameter, from the srengih consideration, is 40 mm, and the life expectancy is 500 hr. (i) If in another condition, th bearing outer ring is rotating and is subjected to light shock, how life of the bearing change? om 5. (a) The bore of a cylinder of the four-stroke diesel engine is 120 mm. “The maximum ga pressure inside the cylinder i limited 10 § MPa “The cylinder head is made of cast iron and the allowable ens stress is 40 MPa. Determine the thickness ofthe cylinder head The studs, ‘which re made of sic, have anslowable sess of SO MPa. Calculate {he numberof suds, nominal diameter of suds, and pich of suds. (2) (5) Design a helical compression sping a static and dynamic conditions for sping loaded safety valve a4 shown in Figure for the following data Operating pressure ~ | MPa, Maximum pressure when the valve blows of freely 1.1 MPa, Maximum lt of valve when the pressure s 1.1 MPa = 6 mm, Dia of valve seat = 100mm. (8) wf wip pst Huse Valve b Ly —6\_| A i) 7 7 777) mr 7 A 1 cytes JYYa/ 7 [oY I) 7A 7) 7 7 / | ) % ) (a) Valve closed (Valve open FIGURE 2: SPRING LOADED SAFETY VALVE