What are the precautions for installation, use and maintenance of tensile testing machine?

The tensile tester should be installed in a room with clean, dry, no vibration and room temperature of 20℃±10℃. It is noted that sufficient spare area should be left around the tester for beam bending tests, use of extensometers for testing, and maintenance of equipment.

1. Installation

The main body and force gauge of the tensile tester should be installed on the concrete foundation. The foundation size should be set aside according to the appearance and foundation map, and other devices such as anchor screws and lower jaw screws, as well as other wire installation pipes.

The upper plane of the foundation should be flat and straightened with a leveling ruler. After the foundation is dried, install the test machine.

① Installation and preliminary accuracy of tensile testing machine

Transfer the main body and the dynamometer to the concrete foundation, adjust the distance between the main body and the dynamometer and adjust the direction according to the appearance and foundation map. Then, a thin piece of iron can be inserted into the bottom part of the main body and the dynamometer (between the foundation), and a square level with an accuracy of 0.05/1000 is used to make the correcting.

The preliminary correctiveness of the subject

You can measure it with a square level at two different positions of the vertical and horizontal positions of the two columns. The non-limiting degree must not be greater than 0.3/1000. Then, you can use the square level to lean against the vertical and horizontal positions of the outer surface of the oil cylinder to correct its plumbing degree.

② Correction of the precision of tensile tester

After the above-mentioned preliminary accuracy of the test machine is corrected, the oil pipe, power supply and oil filling are turned on and the preliminary operation and test run is carried out. When the test run is good, the accuracy of the test machine is corrected.

Use a square horizontal instrument to lean on the working platform, align the plumb slature of the oil cylinder, adjust or increase or decrease the horns under its base, so that the error must not be greater than 0.10/1000.

After the accuracy of the test machine is found, use cement slurry to fill all the gaps under the machine base to keep the machine base well combined with the cement foundation, and prevent the test machine from being level due to vibration during use.

After the anchor nut is poured, the anchor nut and the test machine are not allowed to be tightened before the cement is dried. (The cement drying time is generally no less than 10-15 days) After the cement is completely dry, tighten the lucky foot nut and review the installation accuracy of the test machine to see if it is consistent with the correcting accuracy. If it does not match, it should be corrected again. During the use of the tensile tester, since the vibration during the test is prone to loosening, the relevant parts should be tightened after the tensile tester is used for a period of time.

2. Take over

When installing the oil pipe with the main body and the dynamometer, the inside of the oil pipe should be washed with kerosene to ensure the cleanliness of the oil circuit. Pay attention to whether the gasket at the joint is complete to prevent oil seeping during high pressure.

3. Select oil specifications

In hydraulic rotation, N68 precision machine tool hydraulic oil can be used, or other oils with similar specifications can be used, and their kinematic viscosity is (100℃) 11-14 centistokes.

4. Oil filling and oil drainage

Open the air filter on the oil tank and pour the oil into the oil tank. The amount of oil injected at one time is about 24 kg. The oil specifications used can be found in the oil specification introduction. When draining oil, just open the oil nozzle at the bottom of the left side of the dynamometer. The service life of the oil is determined based on the climate in various places. If you find that the oil starts to deteriorate or is filthy and cannot be used, you should replace it with new oil.

5. Connect to power

The electrical device of the tensile tester is in the dynamometer and the power supply is three-phase and four-wire system. The circuit between the main body and the dynamometer is connected by a plug. Before powering on, the dust and other impurities in the electrical box should be cleaned. After introducing the power cord, press the "Power" button indicator light on the dynamometer table panel to prove that power supply has started. At this time, you can press the oil pump start button to observe the rotation direction of the motor, and then press the jaw seat lift button to check whether the lifting and lower jaw seat is consistent with the text shown on the button, and at the same time check whether the respective limit switches work.

6. Lubrication

Lubricating oil can be poured on the lower jaw screw to lubricate the screw rod and the screw nut. There is an oil injection hole on the machine base, which injects oil into the oil lubrication worm. The scale of the oil in the oil stool can be measured by the oil measuring needle, and the oil level of the oil stool can be no more than the lower flat part of the oil measuring needle. The lower end of the oil measuring needle is the oil level of the oil in the oil stool.

7. The initial operation and test drive of the oil pump

Press the button on the dynamometer table to start or stop the oil pump from rotating. When the wire connector is first operated or changed after installation, check whether the oil pump oil circuit is unobstructed.

8. Safety device

The main cylinder and hydraulic chuck department of the tensile tester are equipped with protective overflow valves and limit switches.

9. Things to note when operating

① If the oil pump suddenly stops working during the test, the load added should be removed to reduce the oil pressure. After inspection, the oil pump should be restarted for the test. The oil pump should not be started under high pressure or the cause of the accident should be checked.

② If the electrical appliance fails when the tensile tester is working and the start or stop buttons do not work, the power should be cut off immediately to stop the tester from running.

③People who are not operating the machine are prohibited from operating on the machine.

10. Maintenance of tensile testing machine

All parts of the tensile tester should be wiped clean frequently. After wiping without paint, use cotton yarn to dip a small amount of engine oil and wipe it again to prevent rust. During the rainy season, you should pay more attention to wiping. When not in use, use a dust cover to prevent dust from invading.

After each test, the test bench is lowered and the piston does not fall on the bottom of the oil cylinder, leaving a little distance for the next use. All shutters on the dynamometer should not be opened and placed to prevent dust from entering the interior, affecting the sensitive performance of the measuring mechanism.

The oil pump motor should be turned off when the test is suspended.