Torsional and Vibrational
STUDENT NAME STUDENT ID COURSE LECTURER SUBMISSION DATE SUBJECT
MD ATIQUR RAHMAN FAISAL SCM-012154 BACHELOR IN MECHANICAL ENGINEERING DR. CHIA 19th April 2013 ENGINEERING MECHANICS (EAT 227)
Torsion Vibration
Experiment Title: Introduction : Torsion Vibration. Torsion is the twisting of a metallic rod shaped object, when a torque is applied on two sides’ perpendicular to the radius of a uniform cross-sectional bar. To study the response of materials under a torsional force, the torsion test is performed by mounting the specimen onto a torsion testing machine, then applying the twisting moment till failure. The torque and degree of rotation are measured and plotted. It can be seen higher torsion force is required at higher degree of rotation. Normally the test specimens used are of a cylindrical rod type since the stress distribution across the section of the rod is the simplest geometry, which is easy for the calculation of the stresses. Both ends of the cylindrical specimen are tightened to hexagonal socket in which one is fitted to a torque shaft and another is fitted to an input shaft. The twisting moment is applied by turning the input hand wheel to produce torque until specimen fails. When the twisting moment is applied, the torque is reacted by a torque shaft, which moves in relation to the deflection arm. The movement of the deflection arm is measured by a linear potentiometer, which is connected to a calibrated TQ digital torque meter to give readout of the torque in unit of Nm or lb.in. The move we turned the input hand wheel clockwise to increase the degree of rotation, the more torque is produced. At the initial stage, the graphical relationship of the torque and degree of rotation measured is linear as demonstrated. The specimen is elastically deformed and the recovery of the specimen to its original shape is possible if the specimen is unloaded. However, if a high degree of rotation is applied passing a proportional limit, the specimen starts
MD ATIQUR RAHMAN FAISAL SCM-012154 BACHELOR IN MECHANICAL ENGINEERING DR. CHIA 19th April 2013 ENGINEERING MECHANICS (EAT 227)
Torsion Vibration
Experiment Title: Introduction : Torsion Vibration. Torsion is the twisting of a metallic rod shaped object, when a torque is applied on two sides’ perpendicular to the radius of a uniform cross-sectional bar. To study the response of materials under a torsional force, the torsion test is performed by mounting the specimen onto a torsion testing machine, then applying the twisting moment till failure. The torque and degree of rotation are measured and plotted. It can be seen higher torsion force is required at higher degree of rotation. Normally the test specimens used are of a cylindrical rod type since the stress distribution across the section of the rod is the simplest geometry, which is easy for the calculation of the stresses. Both ends of the cylindrical specimen are tightened to hexagonal socket in which one is fitted to a torque shaft and another is fitted to an input shaft. The twisting moment is applied by turning the input hand wheel to produce torque until specimen fails. When the twisting moment is applied, the torque is reacted by a torque shaft, which moves in relation to the deflection arm. The movement of the deflection arm is measured by a linear potentiometer, which is connected to a calibrated TQ digital torque meter to give readout of the torque in unit of Nm or lb.in. The move we turned the input hand wheel clockwise to increase the degree of rotation, the more torque is produced. At the initial stage, the graphical relationship of the torque and degree of rotation measured is linear as demonstrated. The specimen is elastically deformed and the recovery of the specimen to its original shape is possible if the specimen is unloaded. However, if a high degree of rotation is applied passing a proportional limit, the specimen starts