QUESTION 1 A crankshaft for a locomotive (e. a train) is to be balanced to the...

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QUESTION 1 A crankshaft for a locomotive (e. a train) is to be balanced to the correct ISO 1940-1 grade, What is the correct balancing grade? Just write down the number only (c.g. G 2.5 would be entered as 2.5). See questionnaire resource sheet No 2. QUESTION 2 For the crankshaft in Q 1, assume it is of homogenous material and is turning at 1800 rev/min. Find the acceptable specific unbalance "e" in micrometres. No tolerance allowed. QUESTION 3 For the same crankshaft in Q1 2 as its turning parts weigh 150 kg, find the residual unbalance "U" in gmm. No tolerance allowed. QUESTION 4 For the same crankshaft in Q1 3, find the offset of its centre of mass from the shaft centreline in mm. No tolerance allowed. QUESTION S For the same crankshaft in Q1 4, find the out of balance force in N QUESTION 6 For the same crankshaft in Q1-5, find the actual value of "eu" in mm/s. ISO 1940-1, Figure 1B Max permissible e (um) PERMISSIBLE RESIDUAL UNBALANCE, e, in g-mm/kg of rotor weight CENTER OF GRAVITY DISPLACEMENT, e, in um Figure 1-B Maximum permissible residual unbalance, ep (From ISO 1940/1) 100000 50000 20000 10000 5000 2000 1000 500 200 100 50 20 10 5 2 1 0.5 0.2 0.1 G630 30 50 100 G 250 G 100 G 40 G 16 4 MAXIMUM SERVICE SPEED G 6.3 200 500 1000 2000 G 2.5 G0.4 ISO 1940-1 standard for balancing 5000 10000 20000 50000 100000 ISO 1940-1, Table 1 Balance quality grades Balance Quality Grade 0 4 000 G 1600 G 630 G 250 G 100 G 40 G 16 G6.3 G 2.5 G1 G0.4 Table 1 Balance quality grades for various groups of representative rigid rotors (From ISO 1940/1) Product of the Relationship (1x1)15 mm/s 4000 1600 630 250 100 40 16 6.3 2.5 1 0.4 Cranks of ngidly mounted sow manne diesel engines with uneven number of cylindery Crankshaldives of rigidly mounted large two-cycle engines Crankshades of rigidly mounted large fourcycle engines Crankshalvdrives of elastically mounted marine diesel engines Crankshaldives of rigidly mounted fast four-cylinder diesel engines Rotor Types General Examples Crankshaldives of fast diesel engines with six or more cylinder Complete engines gasoline or diesel) for cars, trucks and locomotives Car wheels, wheel rims, wheel sets, drive shafts Crankshaldives of elastically mounted fast fourcycle engines with six or more cylinden Crankshaldives of engines of cars, trucks and locomotives Drive shafts propeller shafts, cardan shall with special requirements Parts of crushing machines Parts of agricultural machinery Individual components of engines (pmoline or diesel for cars, trucks and locomotives Canisha/drives of engines with six or more cylinders under special requirements Parts of process plant machines Maine main turbine gears (merchant service) Centrifuge drums Paper machinery rolls; print Fars Assembled art gas turbine rotors Flywheels Pump impellers Machine-tool and general machinery parts Medium and large electric armatures of electric motors having at least 80 mm shalt height without special requirements Small electric armatures, ohes mass produced, in vibration insensitive applications and/or with vibrationsling mountings Individual components of engines under special requirements Gas and steam turbines, including marine main turbines merchant service) Rigid surbo-generators Computer memory drums and discs Turbo-compressors Machine tool drives Medium and large electric armatures with special requirements Small electric armatures not quallying for one or both of the conditions specified for small electric amatures of balance quality grade G 6.3 Turbine driven pumps Tape recorder and phonograph Igramophone) drives Glinding machine drives Small electric armatures with special requirements Spindles, discs and armatures of precision grinders Gyroscopes -260/10, it is measured in revolutions per minute and win radians per second For alocating the permissible residual unbalance to correction planes, refer to "Allocation of U to conaction planes" A crankshahid is an assembly which includes a canishalt, flywheel, clutch, pulley vibration camper, routing portion of connecting rod, etc. 41 Ft en samtal engines are those with a piston velocity of less than 9 fast diesel engines are those of all masses belonging to the cranbhadrive described in note 3 above, ⒸJ. Prince 2021 MECHANICS DYNAMICS II ENME611-PSQ resource sheet No 2 QUESTION 1 A crankshaft for a locomotive (e. a train) is to be balanced to the correct ISO 1940-1 grade, What is the correct balancing grade? Just write down the number only (c.g. G 2.5 would be entered as 2.5). See questionnaire resource sheet No 2. QUESTION 2 For the crankshaft in Q 1, assume it is of homogenous material and is turning at 1800 rev/min. Find the acceptable specific unbalance "e" in micrometres. No tolerance allowed. QUESTION 3 For the same crankshaft in Q1 2 as its turning parts weigh 150 kg, find the residual unbalance "U" in gmm. No tolerance allowed. QUESTION 4 For the same crankshaft in Q1 3, find the offset of its centre of mass from the shaft centreline in mm. No tolerance allowed. QUESTION S For the same crankshaft in Q1 4, find the out of balance force in N QUESTION 6 For the same crankshaft in Q1-5, find the actual value of "eu" in mm/s. ISO 1940-1, Figure 1B Max permissible e (um) PERMISSIBLE RESIDUAL UNBALANCE, e, in g-mm/kg of rotor weight CENTER OF GRAVITY DISPLACEMENT, e, in um Figure 1-B Maximum permissible residual unbalance, ep (From ISO 1940/1) 100000 50000 20000 10000 5000 2000 1000 500 200 100 50 20 10 5 2 1 0.5 0.2 0.1 G630 30 50 100 G 250 G 100 G 40 G 16 4 MAXIMUM SERVICE SPEED G 6.3 200 500 1000 2000 G 2.5 G0.4 ISO 1940-1 standard for balancing 5000 10000 20000 50000 100000 ISO 1940-1, Table 1 Balance quality grades Balance Quality Grade 0 4 000 G 1600 G 630 G 250 G 100 G 40 G 16 G6.3 G 2.5 G1 G0.4 Table 1 Balance quality grades for various groups of representative rigid rotors (From ISO 1940/1) Product of the Relationship (1x1)15 mm/s 4000 1600 630 250 100 40 16 6.3 2.5 1 0.4 Cranks of ngidly mounted sow manne diesel engines with uneven number of cylindery Crankshaldives of rigidly mounted large two-cycle engines Crankshades of rigidly mounted large fourcycle engines Crankshalvdrives of elastically mounted marine diesel engines Crankshaldives of rigidly mounted fast four-cylinder diesel engines Rotor Types General Examples Crankshaldives of fast diesel engines with six or more cylinder Complete engines gasoline or diesel) for cars, trucks and locomotives Car wheels, wheel rims, wheel sets, drive shafts Crankshaldives of elastically mounted fast fourcycle engines with six or more cylinden Crankshaldives of engines of cars, trucks and locomotives Drive shafts propeller shafts, cardan shall with special requirements Parts of crushing machines Parts of agricultural machinery Individual components of engines (pmoline or diesel for cars, trucks and locomotives Canisha/drives of engines with six or more cylinders under special requirements Parts of process plant machines Maine main turbine gears (merchant service) Centrifuge drums Paper machinery rolls; print Fars Assembled art gas turbine rotors Flywheels Pump impellers Machine-tool and general machinery parts Medium and large electric armatures of electric motors having at least 80 mm shalt height without special requirements Small electric armatures, ohes mass produced, in vibration insensitive applications and/or with vibrationsling mountings Individual components of engines under special requirements Gas and steam turbines, including marine main turbines merchant service) Rigid surbo-generators Computer memory drums and discs Turbo-compressors Machine tool drives Medium and large electric armatures with special requirements Small electric armatures not quallying for one or both of the conditions specified for small electric amatures of balance quality grade G 6.3 Turbine driven pumps Tape recorder and phonograph Igramophone) drives Glinding machine drives Small electric armatures with special requirements Spindles, discs and armatures of precision grinders Gyroscopes -260/10, it is measured in revolutions per minute and win radians per second For alocating the permissible residual unbalance to correction planes, refer to "Allocation of U to conaction planes" A crankshahid is an assembly which includes a canishalt, flywheel, clutch, pulley vibration camper, routing portion of connecting rod, etc. 41 Ft en samtal engines are those with a piston velocity of less than 9 fast diesel engines are those of all masses belonging to the cranbhadrive described in note 3 above, ⒸJ. Prince 2021 MECHANICS DYNAMICS II ENME611-PSQ resource sheet No 2

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