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.
