Working principle and performance characteristics of tensile testing machine

1. The measurement of force value of tensile testing machine is completed by force sensor, expander and data processing system. It is found from the data mechanics that under the condition of small deformation, the strain ε of an elastic element is proportional to the force exerted by the elastic element and also proportional to the elastic deformation. Taking S-type tester sensor as an example, when the sensor is subjected to the effect of tension P, because the elastic element is attached with strain gauge, because the strain of elastic element is positively proportional to the thickness of external force P, the strain gauge can be connected to the measuring circuit, and its output voltage can be measured and the output of the strain gauge can be measured.

2. The deformation measurement is measured by the deformation measurement installation, which is used to measure the deformation of the sample during the experiment. There are two collets on the installation, which are connected with the photoelectric encoder installed on the top of the measurement installation through a series of memory head structure. When the interval between the two collets changes, the axis of the photoelectric encoder is turned, and the photoelectric encoder will have the pulse signal output. Then, the deformation of the sample can be obtained by disposing the signal by the disposal device.

Product characteristics of tensile testing machine:

1. Special software for universal testing machine, windows operating platform;

2. The user interface of all Chinese man-machine dialogue is convenient for operation;

3. The test data and characteristic curve are displayed dynamically in real time with the test process;

4. The experimental curves of the same group can be added, reproduced and compared;

5. The test curve can be amplified locally, accessed arbitrarily and analyzed in sections;

6. It has the function of automatic shift of load range;

7. Automatic test program control, material performance index analysis, report printing and database management;

8. The report can be printed in the format set by the user;

9. The national standard gb/t228-2002 and other test methods shall be implemented;

10. The mechanical performance index of the tested material can be calculated automatically by human-computer interaction, such as elasticity, modulus, yield strength, non proportional elongation stress, etc., and the analysis process can be interfered manually to increase the accuracy of the analysis;

11. The test data is managed by database, all test data and curves are automatically saved, and the test report can be printed in the format required by users;

12. Reserve data interface, which can directly connect to the comprehensive information management network of enterprises (laboratories);

1、 When the tensile testing machine is loaded, the pointer vibrates or stops when it is running

1. Worn clutch gear: need repair or replacement.

2. Wear of skin washer or spring of friction disc: need to replace skin washer or spring.

3. Joystick shift: adjust the joystick to fit well with the alveolar.

2、 Pointer does not return to zero when replacing the weight

1. The installation of tensile testing machine is not horizontal: adjust the level of the testing machine with a level meter.

2. Pendulum not vertical: only a-weight is hung. Adjust the balance weight to be vertical.

3、 The pendulum of tensile testing machine is returned too fast or too slow

1. Improper positioning of buffer valve: adjust the buffer valve to the proper position.

2. Low or too high viscosity of hydraulic oil: when the viscosity of hydraulic oil is too low, the pendulum will fall back quickly, and slow down when the viscosity is high. The hydraulic oil with proper viscosity shall be replaced.

3. Dirty in buffer valve, oil pipe or hydraulic oil: clean buffer valve and oil pipe. Replace the hydraulic oil.

4、 Zero hysteresis or instability of pointer return of tensile testing machine

1. Needle bearing and spindle bearing rusted or greasy: clean or replace the bearing.

2. Tooth bar deformation or gear rod and gear not engaged: straighten the tooth bar or clean, repair gear, groove wheel and other transmission parts.

3. Dirt in the buffer valve: clean the buffer valve.

5、 Positive deviation of indication value of tensile test machine

1. The blade of short arm is loose: tighten the blade tightly.

2. Weight is lighter: weight the weight of a, B and C.

6、 The main reason for negative deviation of indication is that the friction resistance between parts is too large

1. The friction resistance of pointer bearing, cycloidal bearing and force measuring drive parts is too large: mainly adjusting and cleaning bearings and force measuring transmission parts to eliminate abnormal friction resistance.

2. The tension of the upper collet, the spring plate of the driven needle and the friction resistance of the drawing device are large: adjust the tension of the upper collet, the spring plate of the driven needle and the drawing device components to eliminate the abnormal friction resistance.

3. The connecting part of piston rod and swing rod is not flexible: adjust the joint part of both. Make it flexible and easy.

7、 Hysteresis or displacement of driven needle

1. The influence of the force of the spring plate of the driven needle or the friction resistance between the driven pin and the indicator plate: adjust the force of the spring plate of the driven needle or the clearance between the driven pin and the indicator plate.

2. Deviation of the heavy alligator at both ends of the driven pin: adjust the weight of both ends to make it balanced.

8、 Irregular deviation of indication value

1. Oil stain, wear or burr on the gear rod and gear: remove the oil and burr of the gear rod and gear, find out the contact point of the tooth rod when the difference is exceeded, and then correct the gear rod and gear; if the error cannot be eliminated, replace the gear rod and gear.

2. The installation of tensile tester is not horizontal: adjust the level.

3. Bending of tooth bar: straighten or replace the tooth bar, adjust the clearance of rolling groove wheel.

9、 The prompt box information will appear after the computer software is online, and the information will be overloaded.

The solution is to check whether the communication line between computer and testing machine is falling off; check whether the online selection sensor is selected correctly; check the latest test or operation key

Check whether the sensor has been hit during the disk; check whether the calibration or calibration function of software is used before the problem occurs; check whether the calibration value, calibration value or other information in hardware parameters have been changed manually.

10、 The main engine power supply of the test machine is not on and it cannot move up and down.

The solution is to check whether the power line connected to the tester is connected normally; check whether the emergency stop switch is in the state of being screwed up; check whether the power voltage connected to the tester is normal; check whether the fuse on the machine socket is burnt out, please take out the spare fuse and install it.

11、 The main power supply of the test machine is powered, but the equipment can not move up and down.

The solution is to check whether the equipment can not be moved after 15s (time), because the host needs self inspection after starting, which takes about 15s; check whether the upper and lower limit position is more appropriate and there is certain operating space; check whether the power voltage connected to the test machine is normal.