Wire rod steel bars, typically with diameters less than 12mm, are integral to construction projects. To ease transportation and prevent deformation, steel mills roll these bars into rings. However, these rolled bars require secondary processing, such as straightening and shearing, on-site. Traditional straightening methods often affect the bars’ weight deviation, size deviation, straightness, and mechanical properties, leading to inefficiencies and quality issues in construction.
The Need for Modern Processing Equipment
As construction projects expand, the demand for steel bars increases, and traditional methods become insufficient due to their slow speed and poor accuracy. Modern engineering quality standards necessitate high precision in steel bar processing. Consequently, CNC steel bar straightening and cutting machines have emerged as essential equipment to meet these needs.
CNC Steel Bar Straightening and Cutting Machines
CNC steel bar straightening and cutting machines are advanced equipment designed to straighten, size, and shear wire rod steel bars efficiently. These machines consist of several components:
- Steel Bar Pay-off Frame: Holds the rolled wire rods.
- Wire Management Frame: Guides the wire rods into the straightening process.
- Straightening Host: The core component where straightening occurs.
- Material Receiving Frame: Collects the straightened and cut bars.
The machines operate in a high-speed, automated flow-line manner, significantly enhancing production efficiency.
Straightening Methods
CNC machines employ two main straightening methods:
- Rotary Straightening with a Hub:
- Uses high-speed rotation and staggered straightening blocks.
- The wire is bent multiple times, gradually straightening.
- Provides good straightness and speed but can damage the bar’s surface.
- Parallel Roller Straightening:
- Uses two rows of multi-wheel rollers arranged in an interlaced manner.
- Directly deforms and straightens the steel bars.
- Slightly slower but maintains the integrity of the steel bar surface.
Advantages of CNC Machines
- High Precision and Efficiency:
- Controlled by high-precision servo motors and encoders.
- Length errors are generally within ±3mm.
- Rotary equipment uses a flying shear mechanism, allowing continuous cutting without stopping.
- Roller machines have all active lower wheels with internal gear + synchronous belt transmission for better accuracy and speed.
- Automation and Intelligence:
- Features human-computer interaction via touch screens.
- Tasks can be manually input or assigned through a control center.
- Automatic operation and task status updates enhance convenience and efficiency.
Safety Operating Procedures
To ensure safe and efficient operation of CNC steel bar straightening and cutting machines, follow these guidelines:
- Pre-Work Checks:
- Tighten all connecting bolts and ensure proper lubrication.
- Remove any foreign objects from the machine.
- Install all safety guards and protective devices firmly.
- Machine Setup:
- Install the straightening machine smoothly.
- Align the material rack, material trough, straightening guide cylinder, and cutting knife hole.
- Ensure the motor has zero connection and leakage protection.
- Operational Checks:
- Test the machine at idle speed.
- Adjust gaps, tighten bolts, and fill oil levels.
- Only start work after confirming normal operation.
- During Operation:
- Stop and check immediately if abnormal conditions or noises occur.
- Select appropriate straightening blocks and transmission speeds based on steel bar diameter.
- Cover all protective parts and fix straightening blocks before feeding.
- Cut off the non-straight ends of steel bars before feeding.
- Feeding and Straightening:
- Use a 1m steel pipe to guide the steel bar into the machine.
- Maintain a safe distance between hands and the pull wheel.
- Adjust straightening blocks gradually if bars are still bent after initial straightening.
- Length and Accuracy Checks:
- Stop the machine to check the length of cut bars.
- Adjust the limit switch or fixed length plate if necessary.
- Material Handling:
- Ensure round steel bars are placed steadily on the ring frame.
- Stop the machine if wires are tangled or bars are off the frame.
- Position the wire rod rack 5 to 8 meters from the machine at the appropriate height.
- Travel Switch Cam:
- Adjust the cam to move freely and center it in the bearing frame.
- Prevent continuous cutting by ensuring the cam isn’t stuck.
- Safety Around the Machine:
- Keep non-operational personnel away from the machine.
- Be cautious when bars on the material plate are nearly finished to avoid injuries from the ends of the steel bars.
Conclusion
The use of CNC steel bar straightening and cutting machines represents a significant advancement in construction technology. These machines not only improve processing speed and accuracy but also ensure the quality of steel bars meets modern construction standards. By following proper safety procedures, construction sites can leverage these machines to enhance efficiency and safety in steel bar processing.
