Shock Absorber Seam Welding Project

An automotive component manufacturer needed a more repeatable method for welding the circumferential seam on shock absorber outer tubes. Its previous process was affected by interrupted welds, possible leakage points, tube deformation and variation between production runs.

HAIFEI carried out welding trials using the customer’s workpieces and developed a dedicated shock absorber seam welding solution. The project combined controlled tube rotation, application-specific tooling, coordinated welding parameters and stored process programs.

Project Overview

The customer’s name, material grade, tube dimensions, wall thickness, welding settings and production data have not been published.

What Did the Customer Need to Weld?

The customer manufactures tubes and related components for automotive shock absorber assemblies. The outer tube forms part of an oil-containing structure and requires a continuous circumferential weld.

A visible weld alone was not sufficient. The production process also needed to address:

• Continuity around the complete circumference
• Leakage risk at interrupted or incomplete sections
• Local deformation of the thin-wall tube
• Stable tube positioning during rotation
• Repeatable welding conditions between batches
• Parameter storage for compatible product specifications

Leak tightness and joint strength still need to be evaluated according to the customer’s own product standard and test method.

Problems with the Previous Welding Process

Interrupted Weld Sections

The previous segmented process could leave discontinuities where individual weld sections met. Poorly formed transition areas increased the risk of incomplete joining or small leakage paths.

Thin-Wall Tube Deformation

Uneven or excessive heat input could affect tube roundness and produce local dents or distortion. For a shock absorber tube, these dimensional changes may interfere with subsequent assembly or product performance.

Variable Welding Conditions

Changes in welding force, current delivery or travel speed could alter the weld width and formation around the circumference. A process that produced an acceptable weld at one position did not necessarily remain consistent through the complete rotation.

Excessive Operator Dependence

Manual intervention made it more difficult to maintain the same rotation and welding sequence from one part to the next. The customer also lacked a standardized method for storing and recalling approved settings.

How HAIFEI Developed the Welding Solution

1. Welding Trials with Representative Tubes

HAIFEI carried out process trials for the tube specifications supplied by the customer. The trials examined the relationship between:

• Welding current
• Welding speed
• Roller electrode force
• Tube rotation
• Electrode contact
• Workpiece positioning
• Cooling and post-weld stabilization

The objective was to establish a workable process window for the actual tube rather than selecting a machine from diameter alone.

A welding program developed for one tube should not automatically be copied to another. Changes in material, wall thickness, diameter, surface condition or joint design may require new trials.

2. Continuous Circumferential Seam Welding

The selected machine applies resistance seam welding while the shock absorber tube rotates through the welding position. The process forms a continuous circumferential seam instead of relying on separate manual weld sections.

Welding current, roller force and rotational speed must work together. If the tube moves too quickly, the overlapping weld formation may be insufficient. If heat input is excessive, the risk of expulsion, marking or distortion can increase.

HAIFEI configured the welding sequence around the customer’s workpiece and required seam path.

Learn more about the shock absorber automatic seam welding machine used for this type of application.

3. Dedicated Tube Positioning Tooling

A positioning fixture was designed around the shock absorber tube. Its purpose was to establish a repeatable reference and reduce movement or eccentric rotation during welding.

The tooling helped control:

• Tube position
• Circumferential weld location
• Alignment with the roller electrodes
• Movement during rotation
• Removal of the completed workpiece

Tooling design is especially important for cylindrical parts. Even with stable electrical output, poor location or irregular rotation can move the weld away from its intended path.

4. Welding Program Storage

The control system was configured to store welding programs for compatible product specifications. Approved settings can be recalled during changeover instead of being entered manually for every production run.

A stored program does not remove the need for verification. The operator should confirm that the correct tooling, tube specification and inspection plan are in place before production resumes.

What Was Checked During Pre-Acceptance?

The customer reviewed the equipment during pre-acceptance, and the machine was operated continuously to assess the welding process under the tested conditions.

The project review covered:

• Workpiece loading and positioning
• Tube rotation and weld-path stability
• Circumferential weld continuity
• Welding sequence repeatability
• Parameter recall
• Tube condition after welding
• Continuous machine operation

The available project record does not publish a pass-rate percentage, leak-test pressure, cycle time or dimensional result. These figures should only be added when supported by a customer-approved test report.

Final Project Configuration

What Did the Project Address?

The completed solution replaced the interrupted welding sequence with a controlled circumferential seam-welding process. Dedicated tooling provided a more consistent reference for the tube, while coordinated rotation and welding parameters reduced operator-dependent variation.

The project also established a clearer process-development method: test the actual tube, define the relevant variables, store approved programs and verify the welded component against the customer’s inspection requirements.

The machine itself cannot guarantee leak tightness for every tube design. Final results depend on the material, joint geometry, surface condition, tooling, welding schedule and inspection standard.

Frequently Asked Questions

Q1.What welding process is used for the shock absorber tube?

This project uses resistance seam welding. Roller electrodes apply force and conduct welding current while the tube rotates, producing a continuous circumferential seam.

Q2.Why is dedicated tooling necessary?

The tooling locates and supports the cylindrical workpiece during rotation. It helps keep the weld on the intended path and reduces movement or eccentric misalignment.

Q3.How is thin-wall tube deformation controlled?

Deformation is managed by coordinating current, welding speed, roller force, electrode contact, cooling and fixture support. The settings must be validated using the actual tube specification.

Q4.Can the machine weld different tube diameters?

It may be possible when the machine working range and replaceable tooling cover the required specifications. Each material, diameter, wall thickness and joint combination still requires a validated welding program.

Q5.Does seam welding guarantee a leak-tight shock absorber tube?

No welding machine can guarantee leak tightness without application testing. The completed joint should pass the leak or pressure test specified by the customer.

Q6.Can loading and unloading be automated?

Automatic handling can be evaluated according to the tube structure, production output and factory layout. The original project information does not confirm the exact loading and unloading configuration used in this system.

Request a Shock Absorber Welding Evaluation

If you need to weld automotive shock absorber tubes or other cylindrical pressure-containing components, send HAIFEI your drawings, material information, tube dimensions, weld position and inspection requirements.

Representative samples allow the engineering team to evaluate tube positioning, electrode access, welding parameters, tooling and automation requirements before recommending a machine.

contact HAIFEI to discuss your application