A punching press is driven by a constant torque electric motor. The press is provided with a flywheel that rotates at a maximum speed of 225 rpm. Radius of gyration of the flywheel is 0.5 m. The press punches 720 holes per hour, each punching operation takes 2 seconds and requires 15 kNm of energy. Find the motor power required and cross section of the flywheel if the speed of the same must not fall below 200 rpm. The flywheel has a rectangular cross section with width equal to three times the thickness. Density of flywheel material is 5400 kg/m³

A punching press is driven by a constant torque electric motor. The press is provided with a flywheel that rotates at a maximum speed of 225 rpm. Radius of gyration of the flywheel is 0.5 m. The press punches 720 holes per hour, each punching operation takes 2 seconds and requires 15 kNm of energy. Find the motor power required and cross section of the flywheel if the speed of the same must not fall below 200 rpm. The flywheel has a rectangular cross section with width equal to three times the thickness. Density of flywheel material is 5400 kg/m³

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter4: Numerical Analysis Of Heat Conduction

Section: Chapter Questions

Problem 4.49P

See similar textbooks

Similar questions

A single cylinder horizontal engine runs at 120 r.p.m. The length of stroke is 400 mm. The mass of the revolving parts assumed concentrated at the crank pin is 100 kg and mass of the reciprocating parts is 150 kg. Determine the magnitude of the balancing mass required to be placed opposite to the crank at a radius of 150mm which is equivalent to all the revolving and 2/3rd of the reciprocat- ing masses. If the crank turns 30° from the inner dead centre, find the magnitude of the unbalanced force due to the balancing mass.
. During the operation of a punch press, its flywheel decelerates uniformlyfrom 400 rpm to 200 rpm in l sec. The rim of the flywheel weighs 1288 lb, itsinside and outside diameters are 56 in. and 60 in., and it is attached to itshub by 6 spokes. What average shearing force is developed between the rim andeach spoke during the 1 sec interval?
For the same cross-sectional area A , for a square cross-sectional area shaft and a circular cross-sectional area shaft, both of length l, in torsion which has the greater angular twist θ, and by what multiple is it greater ?
A solid steel shaft A of 60 mm diameter rotates at 300 rev/min. Find the greatest power that can be transmitted for a limiting shearing stress of 60 MN/m2in the steel. It is proposed to replace A by a hollow shaft B, of the Same external diameter but with a limiting shearing stress of 75 MN/m2. Determine the internal diameter of B to transmit the same power at the same speed.
The iillustration depicts a prototype design for the High-G Rover. It is made up of an arm that is attached to a shaft that is pinned to a disk. The aarm has a retractable shaft that extends and contracts to cause the disk to rotate. To make the computation easier, let us assumee that the arm does nott rotate A. If the arm's total length is L = 640mm, the distance from the centre of the disk to the shaft pin is r = 112mm, and the arm rotates clockwise at a constant angular velocity of 250.273 rpm. 1.) Would an increase in angular velocity increase point C's linear velocity relative to point A? If so, why or why not? a.) What is the linear velocity of point C with respect to point A if the angular position of the pin (between AB and BC) is 0.578 radians? b.) What is the distance between points A and C if the angular position of the pin (between AB and BC) is 0.578 radians? c.) What is the linear velocity of point C with respect to point A if the angular velocity is increased by 34.34…
a) A single cylinder reciprocating engine has a stroke 40cm and the crank makes 250 r.p.m. The reciprocating parts mass is 60kg and the mass of the revolving parts at 20cm radius is 40kg. If two-thirds of the reciprocating mass and all the revolving mass is to be balanced, what is the balancing mass at a radius of 40cm and what is the residual unbalance force when the crank is at 60º from the top dead centre. b) A shaft is supported at bearing at A and B, 2m apart. A rotor of total mass 30kg is mounted at a point 0.6m from bearing A. Owing to faulty mounting the centre of gravity of the rotor is offset 3mm around the axis of rotation. Calculate the dynamic loads on the bearings when the shaft rotates at 600rev/min. calculate also the maximum and minimum loads on the bearings.
A single cylinder horizontal engine runs at 120 r.p.m. The length of stroke is 400 mm. The mass ofthe revolving parts assumed concentrated at the crank pin is 100 kg and mass of the reciprocatingparts is 150 kg. Determine the magnitude of the balancing mass required to be placed opposite tothe crank at a radius of 150mm which is equivalent to all the revolving and 2/3rd of the reciprocating masses. If the crank turns 30° from the inner dead centre, find the magnitude of the unbalancedforce due to the balancing mass solve graphically
Calculate the maximum torsional rotation for a solid circular section of 40 mm diameter in both shafts from A with respect to D. [Given: G = 75 GPA]
Consider a person holding a vacuum cleaner (idealized as Bar AB). The point where the person holds the handle (point A) is constrained to move along the vertical and has a velocity of 0.12 m/s downwards and is increasing its speed at a constant rate of 0.4 m/s2. This is to move the tail end (Point B) of the cleaner. The tail end of the cleaner has a velocity of 0.0840 m/s to the right and the vacuum cleaner has an angular velocity of 0.0586 rad/s.a) What is the the magnitude of the angular acceleration of the vacuum cleaner (Bar AB)? (1.313, 3.5, 0.875, 1.969) b) What is the magnitude of the acceleration of block B? (0.521, 0.270, 0.1929)
The piston of a reciprocating engine exerts a firce of 180 kN on crosshead when the crank is 35 degree (angle beta) past TDC. If the stroke of the piston is 800 mm and the length of the connecting rod is 1.65 m, find, in kN. a) the guide force FG and , b) the firce on the connecting rod Rc .hint: radius AC is 1/2 of the stroke and Angle "phi" may be solved using sine law. Draw FBD
Please draw the figure. Thank you so much.An engine flywheel and a clutch plate are both connected to a transmission shaft. Let the moment of inertia of the flywheel be I1 and its angular velocity ω1, and let the moment of inertia of the clutch plate be I2 and its angular velocity is ω2. The two discs have then been combined by forces which are applied at their axes of rotation so as not to cause any torque. The discs then reached a common final angular velocity after rotational collision. Find the expression for the final angular velocity.
The turning-moment diagram for an engine consists of two isosceles triangles each with a height equivalent to a torque of 16kNm. The bases of the triangles lie between ? = 0 ? and ? = 180 , and ? = 180? and ? = 360? respectively. If the engine is to rotate with a mean speed of 130 rpm, calculate the following: the mass of the flywheel having a radius of gyration 1.1m to restrict the fluctuation of speed to +1.5% of the mean speed.