1, mechanical * * * earthquake.
2. The installation foundation is not firm enough or the anchor bolts are loose.
3. Air enters the oil system of the hydraulic testing machine.
4. The viscosity of hydraulic oil is too low.
5. There are sundries in the oil delivery valve or the spring stiffness in the oil delivery valve that plays a stabilizing role is too hard or too soft.
6. The oil pump does not work normally, such as some plungers do not work, which leads to uneven oil discharge of the oil pump.
The solutions to the above common faults are as follows: First, check whether there are vibration sources around or whether the anchor screws are loose; And then discharge that oil path; Check whether the viscosity of hydraulic oil is appropriate; Check whether the oil pump works normally.
Second, the load cannot be maintained, and the load is often unloaded. There may be many reasons, but the main ones are as follows:
1, hydraulic oil viscosity is too low;
2. There is a lot of air or loopholes in the hydraulic system;
3. There is dirt in the oil delivery valve or the voltage stabilizing spring is just too small;
4. The oil return valve is damaged, resulting in untidy closing.
In the process of using the electro-hydraulic servo universal testing machine, the methods to eliminate the above problems are as follows: firstly, eliminate the influence of air, check the oil leakage position and eliminate it, replace the hydraulic oil with appropriate viscosity, check the oil delivery valve and oil return valve, clean or replace the new valve and the voltage stabilizing spring with appropriate stiffness.
The electro-hydraulic servo universal testing machine integrates automatic control, automatic measurement, data acquisition, screen display and test result processing. Based on the main engine under the oil cylinder, with imported oil pump, electro-hydraulic servo valve and PC servo controller, multi-channel closed-loop control is realized, and the automatic control and automatic measurement functions in the test process are completed. It has the characteristics of good professionalism, high reliability and easy upgrade, and can be continuously enriched and improved with the development of testing machine measurement and control technology and the change of testing standards.
1. main engine: the oil cylinder is installed under the main engine frame, which greatly reduces the height of the main engine, is convenient for transportation and installation, and has stable and reliable performance. The worm gear and worm structure of the main engine are fixed by different screws. The worm wheel and worm pair are installed in the movable beam, driven by the disk motor, and the movable beam moves up and down through the rotation of the nut. The upper and lower centering stability is good, the test curve is smooth without steps, and the main engine is rigid.
2. Measurement and control system: It consists of electro-hydraulic servo oil source, digital PC servo controller, electro-hydraulic servo valve, pressure sensor, extensometer for measuring sample deformation, photoelectric encoder for measuring displacement, PC measurement and control card for testing machine, printer, multifunctional test software package and electrical control unit.
3. Standard electro-hydraulic servo oil source:
1) is a load adaptive oil inlet throttle speed regulation system, which is designed and manufactured according to the standard modular unit with mature technology and is specially used for electro-hydraulic servo universal testing machine;
2) The oil pump motor with mature technology is selected, with reliable quality and stable performance;
3) The self-developed load adaptive throttle valve with unique technology has stable system pressure, adaptive constant pressure difference flow regulation, no overflow energy consumption and easy PID closed-loop control;
4) Piping system: Pipelines, joints and their seals shall adopt a group kit with stable performance, so as to ensure reliable sealing of the hydraulic system and no oil leakage;
4. Electrical control cabinet:
A, all high-voltage components of the system are concentrated in the high-voltage control cabinet, effectively isolating the high-voltage unit from the weak current unit for measurement and control, and ensuring that the measurement and control system is not disturbed and works stably for a long time;
B, the electric control cabinet is equipped with manual operation buttons, including power switch, emergency stop, oil source oil pump start and stop, etc.