Design a suitable wire rope to lift a load of 13 kN of debris from a well 70 m deep. The rope should have a factor of safety equal to 6. The weight of the bucket is 7.5 kN. The load is lifted with a maximum speed of 150 m/min which is attained in 1 second. Find also the stress induced in the rope due to starting with an initial slack of 250 mm. The average tensile strength of the rope may be taken as 590 d2 Newtons (where d is the rope diameter in mm) for 6 x 19 wire rope. The weight of the rope is 18.5 N/m. Take the diameter of the wire (dw) = 0.063d and area of rope A = 0.38 d².

Design a suitable wire rope to lift a load of 13 kN of debris from a well 70 m deep. The rope should have a factor of safety equal to 6. The weight of the bucket is 7.5 kN. The load is lifted with a maximum speed of 150 m/min which is attained in 1 second. Find also the stress induced in the rope due to starting with an initial slack of 250 mm. The average tensile strength of the rope may be taken as 590 d2 Newtons (where d is the rope diameter in mm) for 6 x 19 wire rope. The weight of the rope is 18.5 N/m. Take the diameter of the wire (dw) = 0.063d and area of rope A = 0.38 d².

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.78P: The figure shows a steel bar being processed by a rolling mill. Given that P=80kN and r =0.016,...

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