Lab (1): Decalage Test
Training course Number:
ELECTRONIC COUNTER MEASURE (ECM) 2043
Technicians of Materials
To undertake a torsion test to destruction in order to determine the subsequent for a steel rod specimen: 1 . To compare the experimental shear modulus (modulus of rigidity) with the tabulated values. 2 . The maximum shear stress on the limit of proportionality or perhaps the proportional limit shear anxiety, 3. The typical characteristics of the torque, viewpoint of turn relationship.
The proportional limit shear tension: the highest shear stress which the material can withstand and still return to it is original geometry is at the limit from the proportional percentage of the graph and is known as the proportional limit shear tension.
1 ) Hibbeler, R. C. " Mechanics of Materials", Prentice-Hall, 7th Copy. 2 . Training Bulletin of Tecquipment Ltd.
Moderate Steel fly fishing rod 6 logistik diameter above 3" duration (overall size including hexagon ends = 5в…ќ" ).
1 . Torsion screening Machine and Torsiometer of Tecquipment Ltd. 2 . Steel rule and micrometer.
G = Shear Modulus (GPa)
D = Span (m)
Big t = Rpm (N. m)
J = Polar instant of inertia
= Angle angle in radians
1 Measure the total length and test diameter of the example of beauty. 2 Draw a line down the length of the degree of the section of the specimen with a pencil this kind of serves as a visual aid to the degree of turn being place on the example of beauty during launching. 3 Attach the example of beauty firmly in the Torsion Screening Machine because indicated in the operating instructionsвЂ”see later. In case the Torsimeter is usually to be used the fixing process should be completed as approved. For each increment of tension record this:
a) Angle of distort of the example of beauty (пЃ¦) in degrees.
b) Applied torque (T)
c) When the flexible limit has become passed always test to destruction with ever increasing amounts of strain, recording for each strain increment, I. Viewpoint of twist in levels.
II. Applied torque.
NOTE: In some tests it may be located unnecessary to use the Torsiometer after the flexible limit has been reached and may need to remove it.
Fig. one particular Typical torsion-test specimens; it truly is mounted between your two brain of a screening machine and twisted. DIMENSION:
Specimen no . 1
Gauge duration (mm)
Test Speed (rpm) (reference only)
2 . Tabulate the outcomes as follows:
Perspective of Twist
Angle of twist
zero. 001 (radians)
Specimen no . 2
Example of beauty Details
Gauge length (mm)
Test Acceleration (rpm) (reference only)
2 . Tabulate the results as follows:
Angle of Twist
Perspective of angle
0. 001 (radians)
Error in the modulus of rigidity:
Give a cover page and a table of contents
Response the following inquiries in the body of your report areas: Introduction:
1 ) Why do we study torsion of beams and members?
2 . Precisely what is the objective of the experiment?
Apparatus and Procedure:
a few. What is the apparatus accustomed to conduct the experiment? Include a picture for the apparatus. some. Mention the experiment treatment very in short , as you do in the laboratory.
Data and Figure:
your five. Plot the applied rpm 'T' against angle of twist пЃ¦ in levels (for almost all specimens employed during the experiment) for the whole test devastation. Plot the results using Excel. Mention the product and Figure (1) and give this a caption.
6. Plot the utilized torque 'T' against viewpoint of distort пЃ¦ in degrees (we will convert it to radians in calculations) to get only the elastic region. Utilize slope (T/пЃ¦) from the chart to determine the worth of modulus of solidity. Also using this graph decide...