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PROCEDURES Experiment 1Thin Cylinder with Open Ends In this experiment we will pressurize the

cylinder in the open ends condition taking readings from all six strain gauges, we will then analyze

the results in various ways to establish some important relationships. Examine the cylinder and the

diagram on the front panel to understand the notation and placement of the strain gauges in

relation to the axis of the cylinder. The experimental method utilizes the SM1007 software to display

and take readings. 1. Having set up and familiarized yourself with the equipment open the pump

release valve and screw in the hand wheel to set up the open ends condition. 2. In the SM1007

software choose OPEN ENDS CONDITION from the EXPERIMENTS menu option. Then connect the

SM1007 unit by selecting CONNECT TO SM1007 from the same menu. The virtual meters on the

screen should now display values of pressure and strain. 3. Close the pump release valve and zero

the readings by selecting ZERO ALL GAUGES from the EXPERIMENTS menu option. All the virtual

strain meters should now read 00.3, and the pressure meter should read 00.01MPa. 4. Take the

first set of readings (at zero) into the data table by selecting RECORD GAUGE READINGS from the

EXPERIMENTS menu option. Display the data table by selecting DATA TABLE in the RESULTS menu. 5.

Pump the handle slowly until a pressure of around 0.5 MPa and record the readings into the data

table again by selecting RECORD GAUGE READINGS from the EXPERIMENT menu option. Wait a fewseconds between pumps for the gauges to stabilize. 6. Carefully increase the pressure in 0.5 MPa

increment, record the readings into the data table until you have reached a value of 3 MPa (Do not

exceed a maximum cylinder pressure of 3.5 MPa). 7. You may print the data table if desired by

pressing the printer button in the top left corner of the table. 8. Disconnect the communications

between the PC and the apparatus by selecting DISCONNECT THE SM1007 from the EXPERIMENT

menu option.

Experiment 2Thin Cylinder with Closed Ends Having completed the analysis of the open ends

condition; we will now test the cylinder taking the same readings as in experiment 1 but with the

cylinder in the closed ends condition to show the effect of the biaxial stress system. 1. Open the

pump release valve and carefully unscrew the hand wheel enough to set up the closed ends

condition. To check that the frame is not transmitting any load, close the pump release valve and

pump the handle and observe the pressure gauge, you may need to pump a number of times as the

oil pushes the pistons outward. 2. Once a pressure of around 3 MPa has been achieved, gently push

and pull the cylinder along its axis, the cylinder should move in the frame indicating that the frame is

not transmitting any load. If it doesnt move, wind the hand wheel out some and try again. 3.

Release the pressure from cylinder by opening the pump release valve. 4. In the SM1007 software

choose CLOSED ENDS CONDITION from the EXPERIMENTS menu option. Then connect the SM1007

unit by selecting CONNECT TO SM1007 from the same menu. The virtual meters on the screen

should now display values of pressure and strain. 5. Repeat steps 3 to 8 in Experiment 1.

Experiment 3Thick Cylinder Strain distribution Select this option to create the Strain Table and

determine the difference between measured and theoretical strain values through the cylinder wall.

1. Ensure the cylinder is at zero pressure by checking that the hand wheel turns freely and the

pressure gauge reads zero. 2. Select ZERO READINGS to zero the pressure and strain signals.

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3. Increase the pressure to about 6.5 MPa, allowing about 5 seconds for the pressure and strain

readings to stabilize and then select TAKE READING to copy the current readings to the data table. 4.

Select PRINT to print the data table if desired, ensure a printer is connected, on-line and correctly set

up. 5. Select GRAPH to draw a graph of strain distribution through the cylinder wall. Experimental

hoop strains are shown by green circles, experimental radial strains by blue circles and theoretical

measurements by white circles. 6. Select PRINT to print the graph if desired.

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Stress distribution Select this option to create the Stress Table and display and print graphs showing

stress distribution through the cylinder wall and calculated stresses against a Lame line. The

following steps should be taken: 1. Select PRINT to print the data table if desired, ensure a printer is

connected, on-line and correctly set-up. 2. Select GRAPH to show a graph of stress distribution

through the cylinder wall. Experimental hoop stresses are shown by green circles, experimental

radial stresses by blue circles and theoretical stresses by white circles. 3. Select LAME GRAPH to

show a graph of calculated stresses against a Lame line for the thick cylinder at the pressure used.

The Lame line is shown as a black line and the experimental data is shown as blue and green circles.

Note that, in order to obtain a straight-line relationship, the X-axis of the graph is 2 1 r . 4. Select

PRINT to print the graph that is currently displayed if desired. 5. Finally select EXIT to return to the

main screen. 6. Once the strain table has been created, the results from it may be used to calculate

the principal stresses on the thick cylinder. The calculation is shown on screen and select PRINT to

print out the result.