1. Overview of Billet Cutting Shear

The Billet Cutting Shear is a specialized industrial machine used to cut hot or cold steel billets into required lengths during the steel rolling process. It is a crucial part of the continuous casting and rolling line, responsible for dividing long steel billets into shorter sections for reheating, rolling, or further processing.

This machine adopts a mechanical or hydraulic drive system to generate strong shearing force, ensuring high cutting precision, smooth section surfaces, and high efficiency.
Billet cutting shears are widely used in steel mills, forging plants, rebar production lines, and metallurgical equipment systems.

Depending on operation mode and design, billet cutting shears can be divided into mechanical crank-type, hydraulic-type, and automatic high-speed shears, each suited to specific billet size ranges and production speeds.

2. Working Principle

The billet cutting shear works based on the principle of opposing blade shearing force.
When a hot or cold billet passes through the shear zone, the upper and lower blades move in a coordinated manner to cut the billet cleanly at a set length.

Key working steps include:

1. Feeding:
   The billet is conveyed into the shear by a Roller Conveyor or manipulator.

2. Positioning:
   The billet length is measured automatically using photoelectric sensors or encoders, and the shear head positions accordingly.

3. Cutting Action:
   The upper blade (movable) is driven by a crank, hydraulic cylinder, or servo actuator to move downward, shearing the billet against the fixed lower blade.

4. Discharging:
   The cut billets are transferred to the next stage, such as reheating furnaces, cooling beds, or Rolling Mills.

The synchronization of feeding, positioning, and cutting is controlled by a PLC or computer system, ensuring high-speed and precise shearing even under continuous production.

3. Structural Composition

A typical Billet Cutting Shear consists of:

1. Frame (Body):
   Heavy-duty welded steel frame ensuring rigidity and vibration resistance.

2. Upper and Lower Blades:
   Made of high-strength alloy tool steel (such as Cr12MoV or H13), heat-treated for hardness and wear resistance.

3. Cutting Mechanism:

• Mechanical Type: Driven by crankshaft and flywheel.

• Hydraulic Type: Powered by hydraulic cylinders.

• Servo Type: Controlled by servo actuators for precision.

4. Transmission System:
   Includes motor, reducer, clutch, coupling, and other power transmission components.

5. Hydraulic Station:
   Provides stable pressure for cutting and blade adjustment.

6. Control System:
   PLC + HMI interface with automatic length setting, fault display, and synchronization control.

7. Feeding & Discharging Rollers:
   Ensure smooth billet transport before and after cutting.

8. Cooling and Lubrication System:
   Cools blades and lubricates moving parts to extend lifespan.

9. Protective Housing and Safety Devices:
   Guard covers, emergency stops, and overload protection ensure operational safety.

4. Performance Characteristics

1. High Cutting Precision:
   Length tolerance within ±2 mm under automatic mode.

2. Strong Shearing Force:
   Capable of cutting billets up to 300×300 mm section.

3. Stable and Efficient:
   Continuous operation synchronized with rolling line.

4. Hydraulic Balance System:
   Ensures smooth blade motion and stable cutting pressure.

5. Long Blade Life:
   Special heat treatment and cooling extend service time.

6. Automatic Operation:
   Fully automated control with data feedback.

7. Low Noise and Vibration:
   Optimized mechanical design and damping base reduce vibration.

8. Safety Protection:
   Intelligent monitoring, fault alarm, and emergency stop system.

5. Control System

The billet cutting shear adopts PLC-based control with an HMI interface for real-time operation.

Functions include:

• Automatic billet length measurement and counting.

• Adjustable cutting frequency and timing.

• Fault diagnostics and data recording.

• Synchronization with rolling mill speed.

• Optional remote monitoring and industrial Ethernet connection.

High-end systems may include servo synchronization control for ultra-high-speed cutting lines.

6. Application Fields

• Continuous casting and rolling lines

• Rebar and wire rod production plants

• Steel billet storage and cutting workshops

• Forging and machining preparation lines

• Metallurgical research and material testing facilities

7. Maintenance and Safety

1. Regularly check blade sharpness and replace when dull.

2. Monitor hydraulic oil temperature and cleanliness.

3. Lubricate transmission and bearing parts daily.

4. Calibrate sensors and encoders monthly.

5. Ensure emergency stops and limit switches function properly.

Conclusion

The Billet Cutting Shear plays a critical role in modern steel manufacturing, offering precision, speed, and reliability for billet processing.
With the advancement of automation and digital control, modern billet shears are becoming more intelligent, efficient, and energy-saving, forming an indispensable part of continuous casting and rolling production lines.