Precise Servo Hydraulic Testing Machine for Tensile and Bend Tests on Weldable Reinforcing Steel-Bar Coil and Decoiled Samples
Working principle:
The main unit adopts a six-column frame structure, featuring four columns and two lead screws. The upper and lower crossbeams form the stretching space, and the lower crossbeam together with the worktable constitutes the compression space. It is composed of an electrical controller, servo valve, load sensor, displacement sensor, extensometer, and computer, forming a closed-loop servo control system. This system is capable of automatically and accurately controlling the testing process and automatically measuring test parameters like test force, displacement, and deformation.
Application:
(1) Use in Tensile Tests:
Test Equipment and Fixture Setup
Special wedge-shaped fixtures are employed to secure both ends of the ribbed steel bar specimen, guaranteeing that the clamping surface is perpendicular to the specimen's axis to prevent eccentric loading which could impact test accuracy. The upper and lower crossbeams form a tensile space, with axial tensile force exerted via the hydraulic system.
Control Mode and Parameter Adjustment
A composite control mode of force control - displacement control is usually adopted: in the initial phase, force is applied at a constant rate (e.g., 10 kN/min), and as it nears the yield point, it switches to displacement control (0.05 - 2 mm/min) for precise capture of the yield strength.
Data Collection and Analysis
The load sensor tracks real-time changes in tensile force, the extensometer documents deformation within the gauge length, and the computer auto-generates the "force - displacement" curve, computing parameters such as specified non-proportional elongation strength (ReL, ReH), tensile strength (Rm), and percentage elongation after fracture (A).
(2) Execution of Bending Tests
Bending Equipment and Approach
Replace with the bending indenter and supports, set the support spacing based on the diameter of the ribbed steel bar (typically 3 times the diameter), utilize a 180° cold bending method, and gradually lower the indenter until the specimen is bent to the specified angle, then check for surface cracks.
Confirmation of Standard Conformity
Pursuant to GB/T 1499.2 - 2018 Steel for the Reinforcement of Concrete - Part 2: Hot - Rolled Ribbed Steel Bars, the specimen surface after the bending test shall be free of visible cracks, verifying that its technological properties meet the requirements for construction steel.
| Characteristic tensile properties |
|
Yield strength,R.
MPa |
Tensile/yield strength ratio,R/R |
Total elongation at maximum force,Age
% |
| B500A |
500 |
1.05 |
2.5 |
| B500B |
500 |
1.08 |
5.0 |
| B500C |
500 |
≥1.15,<1.35 |
7.5 |
Rm/R.characteristic is 1.02 for sizes below 8mm.
A:characteristic is 1.0%for sizes below 8mm.
Values of R.specified are characteristic withp=0.95.
Values of R/R,and Ag specified are characteristic with p=0.90.
Calculate the values of Rmand R.using the nominal cross sectional area. |
| The absolute maximum permissible value of yield strength is 650 MPa. |
For yield strength(Re),the upper yield strength(ReH)shall apply.Determine the yield strength(Re)from
the 0.2%proof strength(Rpo.2)if a yield phenomenon is not present. |
Standards:
ISO 6892, ISO 6934, BS4449, ASTM C39,ISO75001, ASTM A370, ASTM E4, ASTM E8 and BSEN standards.
Matters need attention:
a. During the test, if the oil pump suddenly ceases operation, the test force must be immediately relieved. It is forbidden to start the oil pump or check the cause under high pressure.
b. During the test, if the electrical system suddenly breaks down and the start or stop buttons fail to work, the power supply should be cut off immediately to halt the testing machine's operation.
c. The function of the moving crossbeam is to adjust the testing space. During the test, it is strictly prohibited to start the moving crossbeam when applying or releasing force; otherwise, it may lead to failure of the lifting drive mechanism.
d. Only the operators of this machine are permitted to operate it.
e. When installing the bending supports, take care to calculate the appropriate distance between the supports. The lines on the supports mark the position of the rollers' centerlines.
Main technical parameters:
| Model |
WAW-1000G |
| Structure |
4 columns and 2 screws |
|
Control way
|
loading process manual control,computer automatic data dealing |
| Max.load (kN) |
1000kN |
| Load accuracy |
≤±0.5% |
| Load range |
2%-100%FS |
| Isokinetic stress control range |
2-60 (N/mm2•S-1) |
| Stress rate error |
≤±0.5% |
| Load resolution |
1/600000 |
| Deformation Measurement Range |
2%～100%FS |
| Deformation accuracy |
≤±0.5% |
| Displacement resolution (mm) |
0.01 |
| Displacement error |
≤±0.5% |
| Max.piston stroke(mm) |
250 |
| Max piston moving speed |
0.5-100 mm/min Manual adjustment |
| Crosshead lifting speed |
300mm/min |
| Max. tension test space |
700mm (can customize) |
| Max.Compression Test Space |
600mm (can customize) |
| Clamping method |
Hydraulic clamp |
| Round specimen clamping range (mm) |
φ13-φ60 mm(13-26,26-40,40-60) |
| Flat specimen clamping range (mm) |
0-15,15-30 mm |
| Flat specimen clamping width(mm) |
80 |
| Compression plate size (mm) |
200*200 |
| Bending roller distance(mm) |
450 |
| Width of bending rollers (mm) |
120 |
| Power supply |
3-phase,AC380V, 50Hz(can be customized) |
| Weight and size |
3200KG,1060mm*850*2370mm |
Packing and Shipping:
Frequently Asked Questions:
Q1. Are your company a trading one or a factory?
A: Factory-trade integration. We have 18 years of experience focusing on the test instruments field and 14 years of export experience.
Q2. How to choose the most suitable products?
A: Our professional team will provide you with the best recommendations as long as you inform us of the type of test you need to conduct and the required specifications.
Q3. What's the delivery term?
A: Most of the time, we have stock in the factory. If there is no stock, the delivery time is usually 15-20 working days after receiving the deposit.
If you are in urgent need, we can consider making special arrangements for you.
Q4. Do you accept customization service?
A: Yes, of course. We can not only provide standard machines but also customized ones according to your requirements.
Feel free to tell us your needs, and we will try our best to meet them.
Q5. Can we visit your factory before placing an order?
A: Yes, we warmly welcome and sincerely invite you or your team to visit our factory. We will assist in arranging accommodation and pick you up from the airport.
Q6. How about your warranty?
A: Generally, our warranty period is one year. Within the warranty period, we can provide technical support and replacement of spare parts. If necessary, our engineers may visit your location to offer better service.
Q7. How about the packaging for the machines? Is it safely protected during transportation?
A: Our machines are packed in standard export wooden crates, which ensure they won't be damaged. We have delivered many testing machines abroad by sea or air without any damage.
