The core equipment of bridge bearing detection | ｜YAW-5000J microcomputer-controlled electro-hydraulic servo 500-ton compression-shear testing machine

introduction
Plate-type, basin-type and ball-type rubber bearings matched with highway and railway bridges are the core components of bearing and damping of bridges, and their mechanical properties such as compression resistance, shear resistance, friction and corner angle directly affect the long-term operation safety of bridges. In order to complete the full set of national standard testing of various bearings in compliance, an integrated high-precision compression-shear testing machine is a necessary equipment. Today, I will explain in detail the YAW-5000J microcomputer-controlled electro-hydraulic servo compression-shear testing machine independently developed by Jinan Liling, which is also a professional testing equipment selected by bearing manufacturers and third-party testing institutions.

First, the structural design of the whole machine, and the high rigid structure ensures the detection accuracy.
This machine adopts a frame structure with four columns under the oil cylinder. The base and cross beam are integrally cast and formed, and the internal reinforcing ribs are reasonably arranged. The rigidity and strength of the whole machine are sufficient. The deformation of the frame is strictly controlled within the allowable range of the standard under full load, and the accuracy of force and deformation measurement data is guaranteed from the hardware source. The test space of the equipment can be adjusted steplessly from 0 to 0~1000mm, and the beam can be lifted and lowered by means of motor, sprocket and screw nut drive, so as to adapt to bearing samples with different heights and specifications. The whole machine is equipped with an electric feeding trolley and a shearing trolley. The two trolleys share the ground level guide rail, and the large support can complete the sample entry and exit by electric control without manual lifting, which reduces the intensity of manual operation and the requirements for high-rise installation of the laboratory.
The whole machine is divided into three sets of independent servo loading units: 5000kN vertical loading unit, 1000kN transverse shearing unit and 300kN corner loading unit. The three systems are independently closed-loop controlled, which can carry out single mechanical test independently, and can also complete combined tests of vertical preloading+horizontal shearing, vertical pressure maintaining+angular deflection, covering all testing items of various rubber bearings on highways and railways.

Two or three loading systems, full coverage bearing detection standard
(a) vertical loading system (maximum test force of 5000kN)
The vertical system is the core pressure-bearing module of the equipment, which adopts plunger-type lower oil cylinder, the inner hole of the oil cylinder is honed and finished, and it is equipped with two-stage composite seal of imported stern seal and gap oil film, which can keep the pressure under high pressure for a long time without leakage. It is equipped with a high-precision column pressure sensor, with a force measuring range of 2%~100% FS and an indication accuracy of 1%. The system is equipped with four grating digital displacement sensors, and the vertical deformation measurement division value is 0.001mm, and the measurement range is 0 ~ 30 mm; The maximum stroke of the oil cylinder is 200mm, the no-load moving speed is adjustable from 0 to 50 mm/min, and it can be pressurized at a uniform speed according to the standard rate of 0.03MPa/s in the specification, which meets all the test requirements of compressive elastic modulus, ultimate compressive strength and vertical bearing capacity of basin and ball bearings.
(2) transverse shear system (maximum test force 1000kN)
The shearing unit is equipped with a single-output-rod double-acting servo oil cylinder, and the shearing trolley is equipped with a floating lifting oil cylinder, so that the overall height of the shearing device can be adjusted freely, so as to ensure that the axis of the load cell coincides with the axis of the shearing drawing plate and eliminate the data deviation caused by eccentricity. The system uses a 0.3-level high-precision load sensor and two grating displacement sensors to collect shear deformation, with a deformation index of 0.01mm and a measuring range of 0 ~ 150 mm; The shearing trolley travels electrically all the way, without manual push and pull. It can carry out the test of shear elastic modulus, shear adhesion and friction coefficient of bearings, which fully meets the industry standards of highway bearings such as JT/T 4-2004 and JT/T 391-2019.
(3) Angle loading system (maximum jacking force 300kN)
The corner unit is specially designed for detecting the rotation performance of plate, basin and ball bearings. Four grating displacement sensors synchronously collect the overturning deformation of the bearings, with a deformation index of 0.001mm and a measuring range of 0 ~ 30 mm.. The cylinder stroke is 150mm, the moving speed is infinitely adjustable from 0 mm/min to 60 mm/min, and the servo valve accurately guarantees the load, which meets the TB/T series railway bearing and the national standard spherical bearing rotation angle test specification.

Third, load adaptive hydraulic oil source, low heating, energy saving and stability.
The equipment is equipped with an independent water-cooled hydraulic station. The core pump body adopts Mazuqi imported low-noise piston pump of the same level, the servo valve adopts Italian ATOS brand, and the whole oil circuit is a load-adaptive oil inlet throttle speed regulation circuit. The system can automatically adjust the oil supply pressure difference with the real-time test force, run at low pressure without load and boost the pressure synchronously with loading, effectively reducing energy consumption and oil temperature; When the equipment is continuously tested under 50% rated load, the oil temperature shall not be higher than 55℃. Built-in high-pressure filter with 5μm precision and brand-new O-ring sealing structure in the oil circuit can avoid servo valve blockage and oil leakage in the pipeline. The equipment requires the use of 46# antiwear hydraulic oil, which shall be provided by the user. The oil tank is equipped with dual monitoring devices for liquid level and oil temperature. The conventional service cycle of hydraulic oil is 1 year, and the replacement cycle can be adjusted appropriately according to the site climate. All pipes of the hydraulic system are connected by professionals in a standardized way, and the hoses are not twisted and wound, so the sealing performance is reliable.

4. MaxTest special measurement and control software, which conforms to the whole industry detection standard.
The equipment is equipped with MaxTest special measurement and control software for bridge bearings, which is compatible with Windows XP and Win7 operating systems, and fully meets all national standards and line standards related to bearings such as JB/T 11582-2013, JT/T, TB/T, GB 20688.4-2007 and GB/T 17955-2009.
Software core function
1. Hierarchical authority control: distinguish the authority of ordinary operators and administrators, and only administrators can calibrate the system and modify the hardware parameters to prevent the parameters from being changed by mistake;
2. Built-in standardized test procedures: test templates such as precast slab compression, slab shear, friction coefficient, basin vertical bearing capacity, bearing angle, etc., which can be automatically run after selecting specifications;
3. Multi-closed-loop control mode: support constant-speed force, constant-speed displacement, multi-level stress maintenance and cyclic preloading, and preloading times, load holding time and loading rate can be customized according to standards;
4. Real-time display of multi-curves: seven kinds of curves, including force-time, force-deformation and stress-strain, are recorded synchronously, and scaling, saving pictures and exporting text are supported;
5.Excel standardized report: 8 sets of special test templates for bearings are built in. After the test, the data can be exported with one key, and the results can be calculated automatically, which supports self-defined report format;
6. Full-channel calibration function: vertical force, shear force, corner force and displacement of each channel can be calibrated with one key by software, and the calibration process is simple;
7. Program-controlled self-defining function: Professional users can write multi-step test programs by themselves to adapt to special non-standard detection requirements.

Five, multiple safety protection, the whole test to avoid risks.
Double protection of equipment hardware and software, with multiple security mechanisms;
1. Overload protection: when the test force exceeds 2%~5% of the rated load, the system will automatically release pressure and stop;
2. Travel limit: the vertical, shear and corner cylinders automatically lock when they reach the limit position to prevent parts from being damaged by impact;
3. Oil source protection: If the oil temperature exceeds the standard and the oil tank level is insufficient, it will automatically give an audible and visual alarm and cut off the oil pump;
4. Double emergency stop device: the integrated control cabinet and wireless remote controller are equipped with emergency stop buttons, which can stop with one button for sudden failure;
5. Safe operation of weak current: the panel control adopts 24V weak current, and the whole machine is powered by 380V three-phase alternating current, and the layout of strong and weak current is separated to prevent electric shock;
6. Wireless remote control: The remote controller can independently control the movements of the beam, the feeding trolley, the shearing trolley and the floating oil cylinder, and the operation does not need to go back and forth to the control cabinet.

Sixth, the applicable scenario
1. Third-party engineering inspection agency: bridge bearing type inspection, approach sampling inspection;
2. Rubber bearing manufacturer: self-inspection of finished products in the workshop;
3. Transportation, railway research institutes and university laboratories: research on mechanical properties of new bearing materials;
4. Quality inspection unit of road and bridge engineering: quality verification of bearings of highway and railway projects.