First, the full-automatic concrete pressure testing machine is a constant stress testing machine, which is an upgraded product of a common pressure testing base. The computer digital control effectively avoids the influence of manual operation. It is used to determine the compressive strength of brick, stone, concrete and other building materials. Use electro-hydraulic loading, sensor force measurement, digital display force value, printer printing force value data, and conversion of compressive strength. It conforms to the national standard "Standard for Experimental Methods of Mechanical Performance of General Concrete". It should manually control the loading speed, and has a loading speed indicating device, peak hold, and overload protection functions.
★活塞直径 * A大行程： 直径250×30mm
Technical parameters of fully automatic concrete pressure tester
★ A large load: 2000KN
★ Accuracy of displayed value: Level 1
★ A small resolution: 0.1KN
★ A large distance between pressure plates: 320mm
★ Upper and lower pressure plate specifications: 220 × 250mm
★ Piston diameter * A large stroke: 250 × 30mm diameter
★ Motor power: 0.75KW
★ Input voltage: 380V
★ External dimensions: 880 × 480 × 1400mm
★ Net weight: 850kg
Third, the structure of automatic concrete pressure testing machine
The testing machine is mainly composed of three parts: organism, hydraulic control box and force measuring instrument.
★ Body part
The body of the testing machine is connected to the upper beam by four columns. The upper cross beam of the testing machine is equipped with an adjusting screw. The large handwheel and the nut screw can adjust the no-load height of the testing machine. The lower end of the screw is equipped with a ball. Seat and upper platen. The lower pressure plate is placed on the piston of the oil cylinder. When the test piece is in contact with the upper pressure plate, the upper pressure plate ball seat can self-adjust and balance, so that the test piece and the upper and lower pressure plates are level. The lower pressure plate is engraved with a score line for positioning the test piece. The test piece must be aligned with the score line when testing. The lower pressure plate is provided with a dust cover to prevent or reduce dust from entering the oil cylinder when the piston is raised and lowered, which damages the cylinder body or oil seal. There is a sealing device between the piston and the oil cylinder to prevent oil leakage, but when the piston still leaks a small amount of oil during use, there is a ring-shaped oil groove on the top of the cylinder body, and there is an oil drain channel to discharge and flow back to the large oil tank.
★ Hydraulic operating part
The control box of the concrete constant stress pressure testing machine is mainly composed of an oil tank, an oil pump, an oil filter, a motor, a speed valve, and an oil return valve. The oil pump is a direct-rotating axial five-column pump. When the experimental machine is under loading, it should be manually operated. Control the loading speed valve to control the speed of the piston up and down (this speed is integrated with the safety valve). When the load is unloaded, the oil return valve can be turned and the cylinder will slowly descend. The safety valve of the testing machine has been adjusted to an appropriate position when leaving the factory. In normal use, user A adjusts the safety valve.
★ Please read the meter manual for the meter part
Fourth, the maintenance of automatic concrete pressure testing machine
★ The test machine is installed in a clean and dry temperature with no vibration and no corrosive gas affecting the environment.
★ The testing machine should be kept clean. Parts without a protective layer on the testing machine should be frequently rubbed with oil to prevent corrosion.
★ The oil specification is 46 # anti-wear hydraulic oil.
★ The tester's piston lifting position should not exceed 30mm. A limit scale is installed on the control box of the tester. When the arrow reaches the limit, the oil return valve should be released slowly and slowly, and then the motor will be started for the next test.
Five, calibration of automatic concrete pressure testing machine
★ This testing machine is calibrated once a year.
★ The calibration of the testing machine should be performed under the following conditions:
(1) The room temperature is within 20 ± 10 ℃.
(2) In an environment where the relative humidity is ≤80%.
(3) In a vibration-free environment.
(4) The power supply voltage fluctuation does not exceed ± 10% of the rated voltage, and the voltage is relatively stable.
★ After the instrument is powered on, warm up for 30 minutes and adjust it to zero according to the usage method.
★ Start the motor and repeat the load three times to A large load, then adjust the load display to zero and start the calibration.
★ This test machine only performs the relative error and relative variability calibration of the process value. After calibration, the results should reach:
Relative error of displayed value: ≤ ± 1%
Relative variability of displayed value: ≤ ± 1%