Shanghai Yue Shi Welding Technology Co., Ltd.

The welding parameters of stud welding, such as current, time, and pressure, directly affect the quality of the weld. Precise adjustment is necessary to ensure joint strength, aesthetic shape, and stable performance. Below are the specific impacts of each parameter and optimization suggestions:

I. The Impact of Current

1. Melting Depth and Strength

• Insufficient currentArc heat is insufficient, leading to shallow melting depth and narrow width, which causes the weld seam to be prone to incomplete fusion and penetration defects, resulting in low joint strength.

• Excessive CurrentAn excessively large molten pool may burn through thin plates or cause overheating, resulting in poor weld bead formation (e.g., porosity, cracks) and reduced joint toughness.

• Current must match the bolt diameter and plate thickness. For instance, when welding low-carbon steel, the current formula is:$I\approx 100\times d$（dFor bolt diameter, unit: mm.

II. Influence of Welding Time

1. Molten Pool Formation

• Insufficient timeThe molten pool did not fully expand, and the stud did not completely fuse with the workpiece, which is prone to causing false welding.

• Excessive durationThe molten pool is too large, leading to an expanded heat-affected zone (HAZ), which increases residual stress and may cause deformation or cracking.

• The short-cycle stud welding time typically ranges from 5 to 100ms, with the long-cycle duration depending on the plate thickness. Excessive time can lead to wider weld seams, affecting appearance.

III. The Impact of Pressure

1. Melt Pool Forming

• Insufficient pressurePoor contact between the stud and the workpiece, making it difficult to form the melt pool, leading to poor welding.

• Excessive pressureThe molten pool metal is extruded, resulting in poor weld bead formation and reduced joint strength.

• Pressure must be stable; fluctuations can lead to uneven weld seams. For instance, short-cycle stud welding requires applying a constant pressure via a spring or hydraulic device.

IV. Other Key Parameters

1. Voltage

• Arc length and stability are affected. Overvoltage can lead to longer arcs and dispersed heat; low voltage, on the other hand, results in unstable arcs and is prone to incomplete welding.

• The stud height (arc distance) affects the arc quality. It is generally set between 1.2-1.5mm; too high increases the risk of magnetic deflection, and too low results in insufficient arc formation.

• Inert gases (such as argon) prevent oxidation and contamination, enhancing weld quality. The flow rate must be moderate; too low provides insufficient protection, while too high may interfere with the arc.

Section V: Comprehensive Optimization Recommendations

1. Parameter Matching

• Adjust parameters based on material, bolt diameter, and plate thickness. For instance, when welding a 3mm thin plate, the current needs to be reduced and the time shortened.

• Parameters combinations were determined through a small-scale trial, observing weld bead formation and strength.

• Regularly calibrate welding power sources, inspect welding torches and lifting mechanisms, to ensure stable parameters.

• The weld strength and uniformity of the tissue are verified through bend tests or metallographic inspections.

Example:：
Recommended parameters for welding M6 low carbon steel studs to a 2mm thick steel plate:

• Electric Current600A (No Chinese content provided)$I=100\times d$Calculating

• Time20ms (short cycle)

• Pressure200N (applied through spring pressure)

• Enhance Altitude：1.2mm

By precisely adjusting parameters, we ensure consistent quality in stud welding heads, meeting structural strength and aesthetic requirements.