Flywheel and Springs

150 rpm

A flywheel of mass 500 kg and radius of gyration 1.2 m is running at 300 rpm. By means of a clutch, this flywheel is suddenly connected to another flywheel, mass 2000 kg and radius of gyration 0.6 m, initially at rest. Calculate their common speed of rotation after engagement.

1.612 kg-m²

An engine is designed to develop 10kW of power at a mean speed of 1000 rev/min. Find the moment of inertia, in kg-m2, of a suitable flywheel, assuming a speed variation of ± 1.5% of the mean speed and an energy fluctuation equal to 0.9 of the work done per revolution.

0.00363 cm

A shearing machine requires 150 kg m of energy to shear a steel sheet, and has a normal speed of 3.0 rps, slowing down to 2.8 rps during the shearing process. The flywheel of the machine has a mean diameter of 75 cm and weighs 15.5 kg/cm^3. The width of the rim is 30 cm. If the hub and arms of the flywheel account for 15% of its total weight, find the thickness of the rim in cm.

152.95 kg

What would be the weight of a flywheel in kg if the weight of the rim is 3 times the sum of the weight of the hub and arms. Given the outside diameter and inside diameter to be 24 in and 18 in respectively and the rim width is 4.5 in. (assume steel flywheel)

0.069

A cast iron flywheel with a mean diameter of 36 inches changes speed from 300 rpm to 280 while it gives up 8000 ft-lb of energy. What is the coefficient of fluctuation.

306 kg

A sheet metal working company purchase a shearing machine from a surplus dealer without a flywheel. It is calculated that the machine will use 2380 joules of energy to shear a 1.2 mm thick sheet metal. The flywheel to be used will have a mean diameter of 91.44 cm with a width of 25.4 cm. The normal operating speed is 180 rpm and slows down to 160 rpm during the shearing process. Assuming that the arms and the hub will account for 12% of the rim weight concentrated at the mean diameter and that the material density is 0.26 lb/cu. In. Compute for the weight of the flywheel.

41.1 in

A 48 in diameter spoked steel flywheel having a 12 in wide x 10 in deep rim rotates at 200 rpm. How long a cut (in inches) can be stamped in one inch thick aluminum plate if utimate shearing strength of the aluminum is 40,000 lb/in^2. During stamping, the force exerted by the stamp varies from a maximum F lb at the point of contact to zero lb when the stamp emerges from the metal. Neglect the weight of the flywheel and spokes and use 0.28 lb/in^3 density for flywheel material.

172

A safety valve spring having 9 and ½ coils has the ends squared and ground. The outside diameter of the coil is 115 mm and the wire is 13 mm. It has a free length of 203 mm. Determine the length of the wire to which this spring must be initially compressed to hold a boiler pressure of 1.38 MPa on the seat of 32 mm diameter. Modulus of rigidity is taken as G=80GN/m².

1491 lbs

A crate weighing 4,000 lb is moving at a speed of 4ft/s. It is brought to rest by two compression spring in stopping the crate, the springs are to be compressed 8 in. If the spring index is 6 and the allowable stress is 52,000 psi, determine the maximum load on each springs.

169.7 MPa

A closely coiled helical spring is made of 6 mm diameter steel wire, the mean diameter of the coil is 60 mm and there are 8 coils. Taking the modulus of rigidity as 100 kN/mm2, find the stress in the wire when carrying an axial load of 240 N.

25

Find the number of active coils of a No. 8 wire Helical Spring index of 6, steady load with spring rate of 42.5 lb/in. maximum allowable stress is 60 ksi.

171.6

The stiffness of a spring is 88 N/mm of axial compression. Find the Joules of work to increase the compression from 50 mm to 80 mm.

0.5 in

A weight of 160 lbs falls from a height of 2.5 ft to the center of a horizontal platform mounted on four helical springs. At impact each spring deflects 3 in. Calculate the wire diameter if the maximum design stress is 60,000 psi and spring index of 5.

10

A cantilever spring is composed of six graduated leaves each 2 in. Wide and 3/8 in thick. Determine the deflection if loaded with 1600 lbs at the tip. Length of springs is 27 in.

1.37 in

A 5 ton load is supported by a ½ in by 1 ½ in rectangular wire coil spring with 6 effective coils, 3 in outside diameter.

1.93 in.

Determine the width of the leaves of a six-leaf steel cantilever spring 13 in. Long to carry a load of 375 lb with a deflection of 1 ¼ in. The maximum stress in this spring is limited to 50,000 psi.

1.1144

A helical-coil spring has a mean coil diameter of 1 inch and a wire diameter of 1/8 inch. Determine the curve correction factor of the spring.

1.184

A helical-coil spring has a mean coil diameter of 1 inch and a wire diameter of 1/8 inch. Determine the Wahl factor of the spring.

1.172

A helical-coil spring has a mean coil diameter of 1 inch and a wire diameter of 1/8 inch. Determine the value of Bergstrassar factor of the spring.