The steel bar bending machine is an automated processing device specially designed to bend straight steel bars into specific curved shapes such as rings, arcs, or circles. It is widely used in engineering fields such as construction, bridges, tunnels, and water conservancy projects to produce key components including ring bars for pile foundation steel cages, steel bars for bridge arch frames, and reinforcing bars for circular storage silos. It serves as the core equipment for ensuring the accuracy and efficiency of circular steel bar forming.
Its core structure consists of three major systems: mechanical transmission, circular bending execution, and intelligent control. Each system works in coordination to achieve precise circular bending.
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Mechanical Transmission System
Power drive unit:
Driven by a servo motor or hydraulic motor as the core power source and combined with a high-precision reducer, it provides stable torque for the bending process. The motor power of mainstream equipment ranges from 7.5 to 15 kW. It can automatically adjust the output speed according to the diameter of the steel bars to ensure a smooth and seamless bending operation.
Feed guiding mechanism:
This includes two sets of horizontal and vertical guiding rollers. The spacing of the guiding rollers is adjusted by lead screws to accommodate reinforcing bars of different diameters. The guide rollers are made of high-hardness alloy materials, and their surfaces are chrome-plated, which not only ensures no slippage during feeding but also reduces wear. Their service life exceeds 3,000 hours.
Support and positioning assembly:
Composed of adjustable support rollers and positioning baffles, the spacing of the support rollers can be flexibly adjusted according to the bending radius to ensure the steel bars remain horizontal during bending, thereby avoiding bending deviations caused by sagging due to self-weight.
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Circular Bending Execution System
Core circular bending mechanism:
It adopts a combined structure of "driving wheel + driven wheel." The driving wheel is rotated by the power system, while the driven wheel, pressed tightly against the steel bar by a cylinder or hydraulic device, cooperates with the driving wheel to complete the bending operation.
Arc adjustment device:
By controlling the displacement of the driven wheel through a servo motor, precise adjustment of the bending radius can be achieved, with an accuracy of ±1 mm. The device is equipped with a built-in radius parameter database capable of storing over 50 sets of commonly used bending radius parameters. There is no need for recalibration during switching, greatly improving model-change efficiency.
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Intelligent Control System
Mainstream equipment adopts a PLC numerical control system with a touchscreen human-machine interface. It includes three core functions:
Parameter setting and memory:
Parameters such as the diameter of the reinforcing bar, bending radius, and number of arcs can be input, and the system automatically calculates the optimal bending speed and feed rate.
Real-time monitoring and feedback:
Using displacement and torque sensors, the system monitors radius deviation and load changes during bending in real time. If the deviation exceeds the set range, the machine automatically stops and triggers an alarm.
Fault diagnosis and maintenance prompts:
It can automatically identify more than 20 common faults, such as motor overload or abnormal hydraulic pressure, and display corresponding fault codes and solutions, thereby reducing maintenance difficulty.
Core Workflow
Parameter initialization:
The operator inputs parameters such as steel bar specifications (diameter, material), bending radius, arc length, and cutting position through the control system. The system automatically matches the power output parameters and the positions of the guiding mechanisms to complete equipment preheating (hydraulic system pressure rises to 10–15 MPa).
Steel bar feeding and positioning:
The operator manually places the straight steel bars into the feed guiding mechanism, pressing one end tightly against the positioning baffle to ensure correct alignment. After startup, the guide rollers drive the steel bars toward the bending mechanism, while the support and positioning assemblies operate simultaneously to maintain horizontal positioning.
Precise circular bending operation:
The rotation of the driving wheel moves the steel bar, while the driven wheel, pressed tightly against it by hydraulic pressure, bends the bar into an arc of the set radius. During the process, displacement sensors monitor the bending radius in real time. If any deviation occurs, the system immediately adjusts the position of the driven wheel for correction.