About Linear Vibration Welding

Linear Vibration Welding is a frictional welding technique capable of producing strong, air-tight welds in thermoplastic parts.

In this process, vibration occurs by transverse reciprocating motion controlled electro-magnetically by a swing frame assembly containing precision springs, electromagnets and an electromagnetic drive assembly which controls the amplitude and frequency of the vibrating head.

Friction is achieved through motion between two parts, one fixed, the other reciprocating at a controlled amplitude and frequency while clamped under pressure. Melt occurs only at the interface of the joint area of the plastic part halves.

Linear Vibration Welding Process Advantages

  • Ability to weld large parts and complex shapes.
  • Fast cycle times.
  • Compatible with most thermoplastics.
  • Ideal for welding of PA materials.
  • Ability to weld several dissimilar materials.
  • No consumables, fumes or emissions.
  • High strength, hermetic welds are typical.
  • Multiple parts per cycle can be welded.
  • Heat confined to weld interface.
  • Easily automated.
  • Low cost, quick change tooling.
  • Low maintenance.
  • Low power consumption.

Linear Vibration Welding Process:


Part halves are placed into and securely gripped by precision holding fixtures which insure adequate support and accurate alignment of the part halves throughout the vibration welding process.

Vibration Welding Step One



The lower holding fixture rises upward to close against the upper holding fixture,   compressing the part halves to be welded together.

Vibration Welding Step Two



Friction (heat) begins by vibration controlled by alternate energizing of electromagnets on the swing frame assembly. This pulsation propels the vibrating platen and the upper tooling fixture alternately left and right, generating a peak to peak movement of up to 0.070 inches.

Vibration Welding Step Three


Vibration halts and the holding fixtures maintain clamping force, allowing the parts to cool under pressure.

Vibration Welding Step Four



When cooling is complete, the lower fixture lowers and the finished part may be unloaded.

Vibration Welding StepFive

Our existing line of vibration welders includes four unique sized models.  Hydraulic and pneumatic versions are available.  From manually loaded and unloaded machines to semi and fully automated in-line systems, each of our vibration welders is designed to accommodate a specific range of application requirements.

Critical Vibration Welder Parameters:

  • Frequency
  • Amplitude
  • Weld Force
  • Weld Collapse/Absolute Distance
  • Weld Time
  • Hold/Cool Time
  • Hold/Cool Force

Linear Vibration Welding Melt Phases:

Linear Vibration Welding Melt Phase Diagram

  • Phase 1 – Heat is generated at the parts joint surface.  No melting has started at this point.
  • Phase 2 – Melt-down (displacement) initiates as frictional heat is created.
  • Phase 3 – Material surface is melted and approaches consistent melt-down across joint.
  • Phase 4 – Hold time for polymer cooling