000-S Tension-Compression Machine Description-H50KS Students PDF

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Download 000-S Tension-Compression Machine Description-H50KS Students PDF

Description

Laboratory Experiment

Mechanics of Materials Lab -MENG 360L

M1, M2, M3 and M6

H50KS

TENSION-COMPRESSION Machine Description Description of the Testing Machine The unit H50KS is a bench top testing machine for determining Tension, Compression Shear, Flexure and other mechanical and physical properties of materials. The controls are contained in a rugged Control Display Unit which has backlit LCD display and large alpha numeric keypad. The display unit shows the force and displacement values and can also graphically display the test. Dedicated function keys provide zeroing, printing, crosshead return and quick selection of pre-programmed crosshead speeds. Crosshead control keys are provided for selection of pre-selected dual test speeds, jog speed and direction of travel. The alpha/numeric keypad permits the inputting of test data, selecting test control parameters. There may be many aspects of materials testing in particular the type of grips used and additional optional equipment, such as Extensometers, Printers, Computer Systems and Software. The display: will always go to the Panel Display Mode as when turning the machine ON. This mode will display the Force, Extension and Auxiliary values on the left and the pre-set Test Speeds, Test Parameters and Machine Status on the right.

Fig. 1: Tension-Compression Machine

Function Keys: During a normal test sequence, pressing one of these keys will perform the function described on the bottom of the key. These are disabled when entering one of the Menu selections. Some function keys perform additional actions when using the menu system

LCD Display

Panel Display Mode

Function keys

Alphanumeric keypad Crosshead control keys Graphic Display Mode

Fig. 2: LCD display with alpha numeric keypad

Page 1 of 8

Mechanics of Materials Lab -MENG 360L

Laboratory Experiment

M1, M2, M3 and M6

H50KS

TENSION-COMPRESSION Machine Description

This key will zero the force display channel. Note - The force can only be zeroed up to 25% of load-cell capacity This key will zero the extension display channel

This key will zero the auxiliary display channel. This key will also reset the cycle counter to zero This key will print out the current Results and/or Graph(s) to an optional Laser Printer This key will return the crosshead to zero on the extension channel

Table 1: Function keys description

Load Cell: the load cells are mounted under the moving crosshead with a mounting stud, and a breaker bar provided for tightening the load cell in place. Again care must be taken when mounting the load cell as it is handed. Mounting Stud

Breaker bar

Cross head

Load cell plug Load cell slot

Safe Area Sensitive Area

Fig. 3: Load Cell mounting

Align the load cell with the mounting hole beneath the crosshead. Place the mounting stud through crosshead and screw into load cell. Hold load cell in safe area and position it parallel to the crosshead then fully tighten with breaker bar. Connect load cell by plugging the 15 pin load cell plug connector into load cell socket located beneath and to the right of the moving crosshead.

Page 2 of 8

Laboratory Experiment

Mechanics of Materials Lab -MENG 360L

H50KS

M1, M2, M3 and M6

TENSION-COMPRESSION Machine Description Powering On: Before powering the machine on, check the following

Emergency Stop Switch ON/OFF Power Switch

1. Emergency Stop Switch Before the machine can be turned ON it is necessary to check the position of the emergency stop switch. The function of this switch is to STOP the machine as quickly as possible in the case of an emergency. e.g.:where the machine behaves in an unexpected manner, or when there is a risk of .injury to the operator. The emergency Stop switch should NOT be used as the Machine OFF/ON switch.

Fig. 4: Switches

2. Operation To check if the emergency stop switch is in its normal position rotate the top part of the switch clockwise (direction shown by arrows on top of switch). If the switch had been previously activated, on rotation the top will spring upwards, if no upwards movement is felt the switch is already in its normal position. Turn the machine ON with the power switch. The control panel STOP Switch LED will now illuminate. If the direction/Stop LEDS are blinking and the alarm beeping the EMERGENCY STOP Switch is probably activated. Reset the emergency stop switch as described in the above section, turn the machine OFF, allowing a few seconds before turning the back ON again.

Mechanical Crosshead Limit Switches

Fig. 5: Limit Switches

Mechanical Limit Switches: Before attempting to move the crosshead in either direction it will be required to set the mechanical crosshead limit switches. The purpose of the limit switches is to reduce the travel of the crosshead enabling a safe working area. A typical example is to protect the load cell and attachments from unforeseen over travel and in doing so avoid a collision. These limit switches are located on the left hand side for machine on a slider rod.

Page 3 of 8

Mechanics of Materials Lab -MENG 360L

Laboratory Experiment

H50KS

M1, M2, M3 and M6

TENSION-COMPRESSION Machine Description The limit switches are held in position by a locking screw. To set the limit switch unlock by turning the locking screw in an anti-clockwise direction and slide to the required new position. Before locking allow for the limit switch striker being at the bottom of the cross head. To lock limit switch rotate locking screw in a clockwise direction Note: To eliminate slippage re-tighten locking screw securely. Upper Crosshead Limit Switch

Crosshead Striker

Lower Crosshead Limit Switch

Crosshead Striker

Release Upper Limit Switch, move crosshead to new position, slide limit switch to crosshead striker, re-tighten

Release Lower Limit Switch, move crosshead to new position, slide limit switch to crosshead striker, re-tighten.

Fig. 6: Limit Switches adjustment

Crosshead Control Keys: There are two cross head directional arrows, a [STOP] key and a [TEST] Mode key. The UP arrow is used for raising the crosshead, the (STOP] key for stopping the crosshead, and the DOWN arrow for lowering the crosshead. Each of these keys has a LED to indicate the mode selected, and is also indicated in the Status Box on the LCD Screen. Pressing one of the directional arrow keys once will run the crosshead at the first Speed (1) setting; pressing the same arrow key again will run the crosshead at the second Speed (2) setting.

Up Key

Up & Alarm Led Stop & Nudge Led

Test Led TEST

Stop Key

Test Key Down Key

Down & Alarm Led

Fig. 7: Up/Down/Stop/Test Keys and LED's

Pressing the zero or [STOP) key when it is already illuminated will activate the JOG Mode, indicated by the LED flashing on the [STOP) key, where pressing one of the arrow keys will run the crosshead at the Jog Speed setting as long as the keys is held down, releasing the arrow will stop the crosshead and pressing the [STOP] when flashing will exit the Jog Mode.

Page 4 of 8

Mechanics of Materials Lab -MENG 360L

Laboratory Experiment

H50KS

M1, M2, M3 and M6

TENSION-COMPRESSION Machine Description Pressing the Emergency Stop Push button in will stop the Crosshead and sound an alarm. The Crosshead Controls LED's will flash and the alarm sound until the emergency stop is pulled out and the drive reset by pressing the [8] key to go to the Default Menu, then the [8] key to check the drive and if "OK", pressing [ENTER] to complete the process. Main Menu System: To access the menu system, press the [menu/ENTER] key or from one of the test screens you can simply press the number of the Menu Selection.

Fig. 8: Main Menu Screen th

Note: dependent on test set up, a 9 option may be available (not shown)

Pressing the [ENTER] key again will exit the menu screen. Menu Structure: 1. Speed 1.1. Speed 1 1.2. Speed 2 1.3. Jog 1.4. Return 2. Peak Hold 2.1. Off 2.2. On 3. Auto Return Set Up 3.1. Off 3.2. Stop 3.3. Return 3.4. Threshold 3 .5. % Chg. F.S. 3.6. % of Peak 4. Limits 4.1. Force Limit 4.2. Ext. Limit 4.3. Cycle Mode 4.4. Jog Limit 4.5. Aux. limit 4.6. Aux. Hold 5. Enter Identifiers 5.1. Product Code 5.2. Date

5.3. Batch Number 5.4. Operator 6. Panel (Graphic) Display 7. Results 7.1. View 7.2. Program. 7.2.1. Result Units 7.2.2. Coincidence Points 7.3. Clear All 7.4. Delete last 8. Setup Defaults 8.1. Force Units 8.1.1. Newton (N) 8.1.2. Kilograms (kgf) 8.1.3. Pounds (Ibf) 8.2. Extension Units 8.2.1. Millimeters 8.2.2. Inches 8.3. Graph/Aux Setup 8.3.1. X Axis Select 8.3.2. Force Start Range 8.3.3. Aux/Ext. Start Range 8.3.4. Aux Channel 8.3.5. Aux Units 8.3.6. Gauge Length 8.3.7. Aux Hold off Force

8.4. Printer Setup 8.4.1. Edit Headers 8.4.2. Edit Identifier Name 8.4.3. Print Out 8.4.4. Curves per Page 8.4.5. Curves Offset 8.5. Display Setup 8.5.1. Contrast 8.5.2. Standby 8.6. Store Recall Test Setup 8.6.1. 8.6.2. 8.6.3. 8.6.4. 8.6.5. 8.7. Language 8.7.1. English 8.8. Reset/System Check 8.9. Serial Port Setup 8.9.1. Band Rate 8.9.2. Data Bits 8.9.3. Stop Bits 8.9.4. Parity 8.9 .5. PC/Gauge/Tx 8.9 .6. Ignore 8.9.7. Mode 9. Thick/Width 9.1. Thickness 9.2. Width

Table 2: Flow Chart of all the available screens

Page 5 of 8

Laboratory Experiment

Mechanics of Materials Lab -MENG 360L

M1, M2, M3 and M6

H50KS

TENSION-COMPRESSION Machine Description Speed Selection: Pressing the [1] key on the Main Menu or from one of the test screens will bring up the Set Speed Menu Screen 1 shown below. The Set Speed menu will show the current settings for Speed 1, Speed 2, Jog and Return Speeds. From this menu the operator selects which speed setting to change by pressing the appropriate number key or press the [ENTER] key to exit the menu. Example: To change the Speed 1 Setting, press the [1] key to go to Menu Screen 1.

Fig. 9: Speed selection

From this menu the operator can either use the function keys to enter one of the pre-set speeds shown or enter a new speed directly using the number keys. To store a pre-set speed, enter the new speed, press the [F5] key, and then the function key to store the new speed under. The other speeds are set the same. Load Limit Alarm: A load limit alarm is flagged when the machine or load cell capacity is exceeded either in tension or compression. The value of the alarm depends upon the load cell fitted and is approximately 9% greater than load cell capacity E.g. if a 10KN load cell was fitted to a H50KS machine the alarm would be triggered at 10.9kN in tension or compression. This system should not be relied on to protect the machine or operator, as the machine's ability to stop prior to damage is greatly reduced at high crosshead speeds. The alarm direction is indicated by the Flashing LED indicator on the appropriate direction key, reporting an alarm message on the control panel and audible alarm. The alarm can be cleared by backing the crosshead off in the opposite direction to reduce the applied force using the appropriate direction key. If the alarm persists it is possible that the load cell has been damaged. Note: A load limit alarm can be triggered if the load cell is not fitted of incorrectly installed. The direction key which is indicating the alarm will be disabled. This is to protect the machine or load cell in the event of incorrect direction selection.

TEST

Load Limit Alarm Indicators

Motor Drive Alarm: The motor drive alarm is flagged in the same way as the emergency stop alarm. Fig. 10: Load Limit Alarm Indicators

Page 6 of 8

Laboratory Experiment

Mechanics of Materials Lab -MENG 360L

M1, M2, M3 and M6

H50KS

TENSION-COMPRESSION Machine Description (Direction and Stop LEOS flashing) This alarm can be triggered by a number of conditions. These conditions are, Motor Position Alarm, Motor Velocity Alarm, Motor over Current Alarm, Motor Drive Temperature Alarm, Motor Drive Over/Under voltage Alarm, and Encoder Fault. To clear the alarm select menu [8] [8], if the alarm persists turn the machine OFF, wait until the machine cools to room temperature and power back ON. If the fault continues, turn OFF machine, isolate from supply and call Lab Supervisor.

Operation Test Navigator Software: Permits PC data recording, saving and results display. Test setting must be loaded for each experiment type and specimen dimensions should be introduced. Test setting also can be Imported/Exported but file destination should be redefined. Zeroing must done by machine function keys before starting the experiment even though the use of Test Navigator dominates the Control of machine. The process during test can be monitored both from display of machine control and PC monitor.

Fig. 11: Loading test setting

Page 7 of 8

Mechanics of Materials Lab -MENG 360L

Laboratory Experiment

M1, M2, M3 and M6

H50KS

TENSION-COMPRESSION Machine Description Machine specification Capacity

50 kN

Force Measuring System

Full bridge strain gauge load cell of Z-Beam construction for use in tension or compression. Two interchangeable load cells are available: 50kN, and 5kN.

Force Accuracy

±0.5% of the indicated load from 2 to 100% of load cell capacity and ±1% down to 1% of the load cell capacity 200 Hz (nominal).

Extension Measuring System:

Precision encoder operated directly from the crosshead driving ball screw for readout of extension (position).

Extension Resolution

0.001 mm (0.0001 in.) of the full crosshead travel

Extension Accuracy

±0.01 mm (±0.0004 in.) or ±0.05% without any load

Speed Accuracy

±0.05% of the set speed (measured over the greater of 2.5mm (0 .1 in.) or one minute without any load.

Power

Rated at 500 Watts at 220/240 Volts, 60 Cycle, Single Phase. An external transformer provides 48 VAC output for the operation of the machine.

Operating Environment

The machine is designed to operate in temperatures of 0 to 38°C (32 to 100 °F) with a non-condensing atmosphere of 10 to 90% Relative Humidity.

Test Speed

Up to 2SkN (2,550kgf, 1,020 Ibf) 0.001 - 500rnm/min (0.001 - 20 in(min) Over 25kN 0.001 - 250mmfmin (0.001 - 10 in/min)

Jog Speed

0.001 - 500 mm/min (0.001 - 20 in/min) Note - Machine may stall if maximum jog speed is used whilst a load of more than 25kN is present

Return Speed

0.001 - 500mm/min (0.001 - 20 in/min)

Test Area

Vertical (no tooling) 1100mm (43.3") Horizontal (between columns) 405mm (16") Depth Unlimited

Table 1: Machine Specifications

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