T= 16 R = (rl+ -1 =nd+8+ 0.158 W p.A 8 = Gd 300 200 Q3: A block brake with a torque of 250 N-m. Its drum rotates at 100 rpm. The length of the block (1) is wice its width (w). Assume, the coefficient of friction P is 0.35. Calculate: (1) the applied load (P) and the hinge-pin reaction (Rx ana Ry) for clockwise rotation of the drum; (2) the applied load and hinge-pin reaction for anticlockwise rotation of the drum; (3) the rate of heat generated during the braking action. (4) The dimensions of the block, if the intensity of pressure between the block and brake drum is 1 MPa. (5) Check whether the brake is self-locking. Rx 50 200 RN Ft RN = 2nN V =- 60 All dimensions in mm T = (F)r wl Rate of heat generated frictional force average velocity

T= 16 R = (rl+ -1 =nd+8+ 0.158 W p.A 8 = Gd 300 200 Q3: A block brake with a torque of 250 N-m. Its drum rotates at 100 rpm. The length of the block (1) is wice its width (w). Assume, the coefficient of friction P is 0.35. Calculate: (1) the applied load (P) and the hinge-pin reaction (Rx ana Ry) for clockwise rotation of the drum; (2) the applied load and hinge-pin reaction for anticlockwise rotation of the drum; (3) the rate of heat generated during the braking action. (4) The dimensions of the block, if the intensity of pressure between the block and brake drum is 1 MPa. (5) Check whether the brake is self-locking. Rx 50 200 RN Ft RN = 2nN V =- 60 All dimensions in mm T = (F)r wl Rate of heat generated frictional force average velocity

Automotive Technology: A Systems Approach (MindTap Course List)

6th Edition

ISBN:9781133612315

Author:Jack Erjavec, Rob Thompson

Publisher:Jack Erjavec, Rob Thompson

Chapter51: Drum Brakes

Section: Chapter Questions

Problem 2RQ: Explain how drum brakes create a self-multiplying brake force.

See similar textbooks

Similar questions

Questlon 3 The simple handbrake shown in figure A has a drum diameter of 400mm and u = (a) 0.35. The angle of lap is 200°. Calculate the brake torque, for clockwise rotation of the drum, if a force of 200N is applied. The handbrake in Question (a) has now been changed to a differential brake, as in figure B. Determine if the drum will or will not lock up for clock wise rotation of the drum. (b) 200N 200
How much horsepower is delivered by a block brake having a drum 120 mm in diameter and a 400 mm brake arm length. The pivot point is 40 mm below the point of tangency and 80mm horizontally between the drum and the shoe. The applied load for clockwise rotation is 24,767N when the drum rotates at 300 rpm. Assume a coefficient of friction of 0.25.
A fan running at 2000 rpm delivers 16,000 cfm against 3 in static pressure thereby consuming 15 brakehorsepower. If the rpm increased to 2200 rpm so that the rpm ratio is 1.1:1, what is the new cfm?A. 17500B. 16600C. 17600D. 16500
42. A block-brake shown below has a face width of 300 mm and a mean co-efficient of friction of 0.25. For an activating force of 400 N, the braking torque in Nm is 200 mm 400 mm - 400 N 300 mm 45° - 150 mm -
A short-shoe drum brake having f = 0.25, a = 1.0 m, b = 0.4 m, c = 50 mm, andr= 0.3 m is to absorb 25 kW at 800 rpm. Determine: 1.1 The actuating force and whether the brake is self-locking. 1.2 The pin reaction at A. Shoe Drum Rotation Figure 1: Short-shoe brake
The following data refers to a laboratory experiment with rope break. Diameter of the flywheel = 1 m, Diameter of rope = 12 mm, Dead weight on the brake 55 kg, Speed of the engine = 200 rpm, spring balance reading = 130 N. Find the brake power of the engine.
b) A differential band brake as shown in Figure 2 is being considered for use with a hoist drum. With the hoist operating at rated load, a brake torque of 4000,000 Nmm is required to hold the drum from slipping. Available space limits the cast-iron brake drum diameter to 650 mm, with brake band contact extending over an angle of 250°. Design values for the brake lining selected are f = 0.40, Pmax = 1.1 MPa.
b) A gasoline engine is specified to be 4-stroke and four-cylinder. It has a bore of 80 mm and a stroke of 100 mm. On test it develops a torque of 75 N.m when running at 3000 rpm. If the clearance volume in each cylinder is 60 cm², the relative efficiency is 0.5 and the calorific value of the fuel is 42 MJ/kg; determine the brake thermal efficiency. Root wicl
A petrol engine running at a speed of 1000 rpm with a torque given to crank is 200 N-m, calculate the brake power produced by engine.
The figure shows an internal rim-type brake having an inside rim diameter of 300 mm and a dimension R 5 125 mm. The shoes have a face width of 40 mm and are both actuated by a force of 2.2 kN. The drum rotates clockwise. The mean coefficient of friction is 0.28. a. Find the maximum pressure and indicate the shoe on which it occurs. b. Estimate the braking torque effected by each shoe, and find the total braking torque. c. Estimate the resulting hinge-pin reactions. 30°- 30°. R 120° 120° Pin Pin 30° 30° Figure 3: An internal rim-type brake
Q5: Explain the Angular Speed Measurement Devices.
A gasoline engine working on four-stroke develops a brake power of 20.9 kW. A Morse Test was conducted on this engine and the brake power (kW) obtained when each cylinder was made inoperative by short circuiting the spark plug are 14.9, 14.3, 14.8 and 14.5 respectively. The test was conducted at constant speed. Find the indicated power, mechanical efficiency and bmep when all the cylinders are firing. The bore of the engine is 75 mm and the stroke is 90 mm. The engine is running at 3000 rpm.