What Are the Key Steps in VCB Production

Production of a VCB (Vacuum Circuit Breaker) involves an integrated series of steps the incorporate the precision of industrial mechanical manufacturing and the finesse of electronic engineering along with the fine balancing act of quality assurance and standard compliance. In the case of GPSwitchgear, an electrical equipment manufacturer, every single step in the VCB production process is optimized for VCBs reliability, VCBs production durability and VCBs production safety right from the initial purchase of the production raw materials to the last purchase of the production raw materials to the final production testing.  VCB production flows across the phase with the interlocking of precision mechanical engineering with electronic engineering, integrated quality testing and compliance with the IEC and ANSI VCB production standards. In the following, we will review the steps in VCB production to understand the phases in the production of VCBs.

Raw Material and Component Selection: The Foundation of High-Quality VCB Production  

The first critical step in VCB production involves identifying and acquiring quality raw materials and core components. This is because components and materials directly affect the VCB’s performance and service life. For the vacuum chamber (the core part of VCB), oxygen-free copper (for the contacts), high-purity ceramic, and epoxy resin (for the chamber casing) are selected because of their particular electrical conductivity, insulation, and corrosion resistance. For the operating mechanism (which is responsible for contact separation), high-strength steel and wear-resistant alloys are necessary to ensure stable mechanical performance over thousands of operating cycles. Furthermore, auxiliary components, such as the insulating bushings, control cables, and protective relays, are required to meet industry standards for reliability. In the VCB production process, GPSwitchgear enforces strict incoming inspection. For instance, conductivity tests for copper contacts and insulation tests for ceramic casings. This inspection eliminates defective parts and ensures that only materials of the highest quality progress to the next VCB production stage to ensure there are no quality risks from substandard components.

Core Component Manufacturing: Precision Production of Vacuum Chamber and Operation Mechanism

When it comes to vcb production, making the core components, and especially the vacuum chamber and operation mechanism, poses a technical challenge. For the vacuum chamber, the copper contacts are first made using CNC lathes to create precise shapes and sizes with flatness tolerances of 0.01mm. This precision is critical for arc extinguishing.  The ceramic or epoxy casing is then made, surface treated by polishing, and coated to improve insulation and surface corrosion resistance. The contact assembly is encased within the chamber, and the chamber evacuated to a high vacuum (10⁻⁶ Pa or higher) using a vacuum pump. Vacuum leak testing is critical to ensure no air (even tiny leaks) enters the chamber, compromising the chamber with arc extinguishing performance. For the operation mechanism, Control Mechanism and Chamber of the Vacuum Circuit Breaker St. Order serial components like springs, linkages or shafts are made by stamping, followed by forging and heat treatment to improve strength and abrasion resistance. Pre-assembly screws are added with precision (assembly tolerance of 0.05mm) to control contact movement. For this production stage, automation is used to reduce the inconsistencies of human error.

VCB Assembly: How Integrated Components Create a Fully Functioning System  

In the VCB assembly stage of production, all the main and auxiliary pieces are combined to create a fully functional unit. It begins with the vacuum chamber and operational mechanism being attached to the metal frame, which is galvanized to withstand erosion. After this step is finished, insulator bushings are attached to the vacuum chamber, linking it to the external high voltage, and the control mechanism is wired to the control panel for remote or local operation by control cables. After this step, safety components are added to boost the VCB safety performance. Protective components like surge arresters and current transformers are added afterward. During assembly, the exact positioning of the components is crucial; the vacuum chamber contacts must align with the operational mechanism linkages for a seamless function. Furthermore, the risk of loose electrical connections is reduced by torque wrench. All electrical connections are tightened to the specified torque which eliminates the risk of loose connections overheating or causing the poor conductivity. Switchgear GPS implements a ‘one-piece flow’ assembly line in VCB production. This method assigns a unique serial number to each VCB. This allows operators to document the assembly steps and quickly trace any assembly details to confirm quality control.

Quality Testing and Inspection: Verifying Performance and Safety Standards

Testing the quality of a VCB is meant to ensure that the assembled VCB meets the specified standards and complies with the established safety standards. Various tests encompass: 1) The electrical performance test is composed of the AC withstand voltage test; the test for insulation; and the current interruption test, which determines whether the VCB can interrupt the rated fault currents. 2) The operation test checks whether the VCB can open and close for over 1000 continuity cycles. The torque test determines whether electrical connections are properly tightened. 3) Environmental adaptability includes the high-temperature test (operating at 60 for 24 hours), the low-temperature test (operating at -40 for 24 hours), and the humidity test (95% for 48 hours) which tests performance in harsh conditions. 4) The safety interlock test checks whether the interlocking functions of the VCB (mechanical and electrical) are working to prevent misoperation. Any VCB that tests failed rework of the VCB to disassemble to ascertain the problem, fix it, and retest it until it is compliant. GPSwitchgear is , completed with a dispatch laboratory, the GPSwitchgear has a laboratory for VCB production in which the most advanced testing equipment, including high current test systems and partial discharge detectors, is designed to test the accuracy and the reliability of the results.

Final Inspection and Packaging: Preparing for Delivery

The last step in VCB production is the final inspection and packaging step to guarantee the VCB is in perfect condition before the delivery to the customers. For the final inspection, there is a visual check to ensure there are no scratches, loose parts, or missing labels, and all test reports are reviewed to check if the VCB meets customer-specific requirements, which could include voltage rating and current capacity. After that, the VCB is cleaned to remove dust or debris that may have accumulated during the assembly to keep the VCB in good condition before transporting, and protective covers are placed on the terminals to ensure they do not get damaged during transportation. For transportation packaging, the VCB is placed in a strong cardboard or wooden box. Shock-absorbent foam padding and moisture-proof film are placed in the box to prevent rust in humid conditions and to absorb any shocks during transportation. For customer use, the package contains a user manual, a test report, and a spare parts kit of items like replacement fuses or gaskets. Each package is also marked with a “shipping inspection label” that contains the name of the inspector and the date. This provides a guarantee of the quality of the VCB and that the customer is receiving a VCB that is technically qualified and safe for on-site installation and use.