2026-10-24
With a Focus on Hongbai Technology’s Servo Welding Gun Technology Based on Hollow Electric Cylinders Abstract Resistance spot welding is a core process in automotive body-in-white (BIW) manufacturing. The welding gun connects mechanical motion with the welding process, making force consistency and electrode movement critical to weld quality and production stability. Two common actuation approaches are pneumatic and electric servo. Pneumatic guns use compressed air to drive a cylinder and are well established, often with a lower initial investment. Servo-driven guns use a servo motor and electric cylinder to program electrode position, movement speed, and the force application sequence. The right choice depends on the material, process requirements, level of control, and integration with the wider production system. This article compares both technologies in terms of force control, process adaptability, and robot integration, with a focus on Hongbai Technology’s hollow electric cylinders for robotic spot welding in electric vehicle manufacturing. Applications include aluminum alloy, high-strength steel, and multi-sheet welding. 1. Force Consistency: The Numbers Behind the Process Force consistency is best evaluated against actual welding parameters. Hongbai’s SHF inverter DC spot welding system lists representative process parameters for steel applications, including: Electrode force: 80–150 kgf Welding current: 2.1–2.8 kA Weld time: 5–8 cycles Aluminum welding can require a substantially different process window. One published application uses the following parameters: Parameter Aluminum welding case Sheet stack 2+2 mm Electrode force 6,000 N Welding current 37,000 A Weld time 180 ms These figures describe a specific application, not universal settings for every material or joint. The practical question is whether the gun can maintain the required process conditions from the first weld to the four-thousandth weld of a production shift. Repeatability over time matters just as much as achieving a target value during initial setup. 2. Pneumatic Spot Welding Guns: A Proven…
