CONCRETE RAILWAYS SLEEPERS & BEARS DYNAMIC TESTING MACHINE

Concrete Railway Sleepers and Bearers Dynamic  Testing Machine

EKE 0102:

EKE 0102 Concrete Railway Sleepers and Bearers Dynamic  Testing Machine, has been designed basically to perform dynamic and fatigue test of railway applications according to EN 13230-2, EN 13230-3 and EN 13230-4   (Prestressed monoblock and twin-block reinforced sleepers and bearers tests) and Low vibrating track system (LVT-System) tests. The test system is also able to perform static and quasi- static loading of test samples in technically specified range.

The test system consists of digital control system, software, high force capacity floor – standing frame, servo – hydraulic actuator and hydraulic power pack. The system can be supplied with just the standard fatigue and dynamic testing capability and also can be modified with appropriate sized servo valve, manifold and hydraulic power unit to suit the particular application.

Floor model standard frames are robust, heavy duty frames with the axial static capacity of 600 kN and dynamic capacity of 500 kN (@280 bar system pressure). Frames are also available in varying load capacities and also in different variations to meet the requirement for both extra wide test space and extended travel. The load frames are rigid 4 column units for superior axial and lateral stiffness , precision aligned. Columns are chrome plated and hardened for easy cleaning and longer life.

The frame are supplied complete with test sample carrying and holding apparatus for easy test setup, upper and lower articulated supports for dynamic tests. Moreover this testing system may perform three and four point flexure test on concrete beams.

The machine is equipped with double ended, equal area liner actuators to generate equal force in both tension and compression. Actuator is mounted on upper crosshead with 300 mm usable stroke length and mounted with manifold attached on it. Servo – valve and accumulators are close coupled in order to improve performance with highest possible response and minimum pressure losses where most accurate test control is achieved. Maximum allowable  piston speed is 40 mm/sec. SSI  type displacement sensor with 5 µm resolution is integrated in the actuators. All dynamic testing systems are equipped precision fatigue rated load cells where they are mounted on piston’s rod end for accurate force measurement and control.

ENKAY uses fully digital servo – hydraulic motion controller for displacement and / or force closed loop control of static and dynamic tests. Control loop time is 1 kHz as standard, but can be adjusted to 4 kHz according to application. Data acquisition rate of the controller is standard 100 Hz but can be adjusted to 4 kHz if the application control algorithm can run in this loop time. Effective resolution of analogue channels 19 bit over full ± 10 V range (18 bit for 0-10 V and ± 5V, 17 bit for 0-5V, 16 bit for 4-20 mA).

The hydraulic power units are specially designed for dynamic performance of concrete sleepers and bearers for railway, which are governed by oil flow and pressure. The series have standard 500 kN dynamic force capability at 280 bar (3000 psi on servo valve) system pressure with standard ratings up to 100 1/min oil flow. For larger oil flows , the unit can be modified to suit customers requirements. Electrical part as indicators, system management buttons and controller is involved in the power pack. Bladder type accumulators are supplied with the power pack in order to compensate and any pressure losses between the HPU and test station , in order to smooth pump ripples. Oil level, oil temperature, filters condition and motor temperature are continuously checked by controller and system has valve prevents excessive increases in pressure. Variable – capacity pump ensure maximum electrical efficiency, consuming only sufficient electrical power to maintain the required flow , even during units allow systems configured to control up four systems independently , this means saving valuable floor space in your lab. Installed isolation manifolds lets hydraulic power system running multiple test station, preventing over pressurization , discharging system pressure separately and power isolation of the stations. According to  the  environment where system is going to be built, air/oil cooler and water/oil cooler is supplied as standard. However alternative closed loop cooler system can be adapted to run unit if customer requests.

PC Software:
Concrete Railway sleepers and bearers testing machine  are controlled by a computer with PC software. It is flexible and user – friendly windows based application software for both   static and dynamic testing. In the software user can create either test methods (Dynamic , fatigue or static) in accordance with EN 13230 or custom test sequences where you can manage to run simple ramp to cyclic waveforms , even arbitrary custom motion profiles. Synchronized 100 Hz data transfer from feedback signals supplies detailed recording of running tests. This rate is flexible up to 4 kHz if the application is applicable. Graphical and numerical monitoring is displayed real time in  the user interface. Data reduction and peak values recording the running in cyclic tests. Safety limits (Pressure and displacement limits) and internal algorithm protect the machine against any fault condition occurred in the system. The software always optimizes the control parameters (PID and feed forward terms) during test in order to adapt actuator control to the changing stiffness characteristic of the specimen. The software also includes an easy calibration check facility. The machine  gives some constant load values and waits there for easy check mechanism.

Technical Specifications:
•    Control : 
        Standard : Force and displacement closed loop controlled.
        Option: Analogue (Stain, Stress) channel closed loop controlled

•    Actuator :  
        Standard : 0.01 to 10 Hz . Frequency 600 kN static 500 kN dynamic force capacity, 300 mm stroke (± 150 mm)
         Option: Different frequencies , force capacities, shorter or longer stroke 0.01 to 10 Hz

•    Hydraulic Power Pack:
        Standard :  Free standing with air cooling unit, one output channel
        Option:  Water/oil cooler, four test station cap 

•    Power Requirements: 
        400 V/AC/ 50 Hz/ 3 Ph + N + E
        65 KVA current ratings