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In the production of electrical equipment such as high- and low-voltage switchgear, transformers, and photovoltaic inverters, busbars (copper and aluminum busbars) serve as the "blood vessels" for current transmission. Their processing precision and efficiency directly impact the equipment's safety performance and production schedule. CNC busbar punching, cutting, and bending machines (referred to as "CNC busbar processing machines") are automated equipment that integrates punching, cutting, and bending functions. Using a CNC system, they achieve high-precision, high-efficiency, and intelligent busbar processing, making them a core component of the modern electrical manufacturing industry.

I. Core Structure and Operating Principle

A CNC busbar punching, cutting, and bending machine is essentially a "multi-process integrated CNC machining center." Its structure is designed around the three core elements of "busbar conveying, process execution, and precision control," and primarily includes the following modules:

1. Main Frame and Feeding System

Rigid Frame: Utilizes a one-piece welded structure (such as Q345 low-alloy steel plate) with an aging treatment to eliminate internal stresses, ensuring stability during processing and preventing deformation that could affect precision. Automatic Feeding Unit: A servo motor drives a ball screw or synchronous belt, coupled with high-precision guide rails for automatic busbar feeding. Positioning accuracy reaches ±0.1mm, meeting complex processing requirements.
2. Three Functional Modules
Punching Unit: Equipped with a library of quickly interchangeable dies (round, waist-shaped, and special-shaped holes), the busbar holes are punched using a hydraulically driven punch. The dies are made of Cr12MoV alloy tool steel, achieving a hardness of HRC58-62, ensuring a service life of over 100,000 cycles. The CNC system allows preset hole coordinates for continuous multi-station punching, eliminating errors associated with manual marking.
Cutting Unit: Hydraulic shearing or laser cutting are the primary technologies used. Hydraulic shearing is suitable for copper/aluminum busbars ≤12mm thick, resulting in smooth, burr-free cuts. Laser cutting (fiber laser) is suitable for high-precision, complex contour cutting, particularly for thin-walled busbars used in new energy equipment, with a cutting accuracy of ±0.05mm. Bending Unit: Utilizing CNC bending dies (with rounded upper dies and V-grooved lower dies), the busbars can be bent into angles (90°, 135°, etc.) or arcs. A servo-hydraulic system controls the bending force, coupled with real-time feedback from angle sensors, ensuring a bending angle error of ≤0.5° and repeatability of ±0.03mm, eliminating the "springback" problem associated with traditional manual bending.
3. CNC Control System
The core system is a dedicated CNC system (such as a custom PLC-based system or an industrial-grade CNC system) that supports G-code programming or graphical programming (automatically generating machining paths by importing busbar drawings from CAD). Operators can set parameters (punch diameter, cutting length, and bending angle) via the touchscreen. The system automatically optimizes the machining sequence to minimize idle time. Self-diagnostic features (such as die wear warnings and abnormal hydraulic pressure indications) also minimize downtime. II. Technical Advantages: The Leap from Manual Operation to Intelligent Processing

Compared to traditional separate equipment (separate punching, cutting, and bending machines) or manual processing, the core advantages of CNC busbar processing machines lie in three key dimensions: precision, efficiency, and intelligence:

1. Improved Processing Accuracy

Punching positioning error is reduced from the traditional ±1mm to ±0.1mm, ensuring precise assembly of busbars and electrical components;

Bending angle consistency is improved by over 80%, eliminating gaps in busbar joints caused by angular deviation and reducing current transmission losses;

The verticality of the cut section reaches 0.02mm/m, eliminating subsequent polishing steps and saving labor costs. 2. Doubled Production Efficiency
The integrated design enables "one-time clamping, multiple processes completed," eliminating busbar transfer time between multiple machines and reducing the processing cycle for a single busbar by over 60%.
Automatic feeding and continuous processing support batch production. For example, processing 100 one-meter-long copper busbars takes only two hours with CNC equipment, compared to 5-6 hours with traditional equipment.
The graphical programming system allows even novice operators to program complex workpieces in just 30 minutes, reducing reliance on skilled labor.
3. Intelligent and Safety Enhancements
Equipped with an infrared sensor safety device, the machine automatically shuts down when the hand enters the processing area. The hydraulic system features overload protection to prevent damage to the mold or workpiece.
Some high-end models support IoT functionality, allowing remote monitoring of processing progress and equipment status through the MES system, enabling production data traceability.
With a built-in material database (including yield strength and rebound coefficient of copper and aluminum), the system automatically adjusts bending force and feed speed to accommodate busbars of different materials. III. Key Operation and Maintenance Points
1. Standardized Operation Procedures
Before machining, confirm the busbar material (copper/aluminum) and thickness, and access the corresponding parameter library in the system to avoid mold damage due to incorrect parameters.
When machining a new workpiece for the first time, perform a "single-step trial run" to check whether the punching position, cutting dimensions, and bending angles meet the drawing requirements.
When replacing the mold, clean the positioning reference surface and use a dial indicator to calibrate the mold perpendicularity to ensure a tight fit with the busbar contact surface.
2. Key Daily Maintenance
Daily checks: guide rail lubricant level (recommended No. 32 hydraulic oil), hydraulic system pressure (usually set to 10-15 MPa), and mold edge wear.
Weekly maintenance: clean cutting debris (especially metal dust from laser cutting), tighten the feed mechanism screws, and calibrate the servo motor encoder.
For long-term storage: release hydraulic system pressure, apply anti-rust oil to the mold, and keep the control cabinet ventilated and dry. 3. Common Troubleshooting
Burrs during punching: This is usually caused by die edge wear, requiring die replacement or edge grinding.
Bending angle deviation: This could be due to angle sensor calibration failure, requiring recalibration. Alternatively, the busbar thickness may exceed the equipment's rated range (e.g., if the equipment's maximum bending thickness is 10mm, processing a 12mm busbar can easily lead to deviation).
Feeding jams: Check the guide rails for foreign objects, the tightness of the timing belt, or any abnormal servo motor driver parameters.
IV. Industry Applications and Development Trends
1. Core Application Areas
Power Equipment: Punching and bending copper busbars in high- and low-voltage switchgear and box-type substations.
New Energy: Aluminum busbar processing for photovoltaic inverters and energy storage battery cabinets (due to lightweighting requirements, the proportion of aluminum busbars has increased to 60%).
Rail Transit: Processing large-section busbars (thickness ≥ 15mm) for subway and high-speed rail traction converters. 2. Technology Development Directions
High Precision: Utilizing closed-loop control with a linear encoder, positioning accuracy is improved to ±0.05mm, meeting the requirements of high-end applications such as aerospace.
Modular Design: Supports rapid replacement of functional modules (such as adding embossing and chamfering units), accommodating small-batch production of multiple products.
Energy-Saving: Utilizes a servo-hydraulic system (reducing energy consumption by 30%) and laser cutting instead of traditional shearing (eliminating waste).
Digital Twin: Predicts processing deformation through virtual simulation (especially springback compensation for thick plate bending), increasing first-pass yield to 99%. V. Selection Recommendations
For small and medium-volume production: Choose a basic model with three integrated functions (punching + shearing + bending), such as entry-level models from domestic brands Jinan Fine and Jiangsu Huayuan (priced approximately 150,000-300,000 RMB).
For large-volume, high-precision production: High-end models with automatic loading and unloading and a mold library (such as those from Germany's TRUMPF and Japan's Amada) are recommended, priced between 500,000 and 1.5 million RMB, suitable for large electrical equipment companies.
For special material processing: For high-hardness alloy busbars, choose an enhanced hydraulic system (maximum punching force ≥ 2000 kN) and ultra-hard molds (such as those coated with tungsten steel).

Technological advances in CNC busbar punching, cutting, and bending machines are driving the electrical manufacturing industry's transition from "extensive processing" to "precision manufacturing." Whether improving product reliability or reducing production costs, their core value lies in breaking through traditional processing bottlenecks through CNC technology, making them a key component of intelligent production of electrical equipment.