HDPE Geomembrane Sheet Welding – Wedge & Extrusion

HDPE geomembranes form the primary barrier in landfills, mining heap-leach pads, wastewater lagoons, and secondary containment systems, where a single defective seam can compromise environmental protection. This course develops the practical competence of geomembrane welding technicians, covering sheet characteristics, deployment, hot wedge and extrusion welding, and seam quality assurance. Participants perform machine checks and trial welds, establish welding parameters for site conditions, and test seams using non-destructive and destructive methods. Emphasis is placed on safe working at height and on slopes, weather limitations, and complete installation records.

Who Should Attend

• Geomembrane welding technicians and installers
• Lining installation crew leaders and supervisors
• Construction quality assurance (CQA) monitors
• Environmental and civil engineers overseeing containment projects

Learning Outcomes

• Describe the properties and specification requirements of HDPE geomembrane sheet
• Plan sheet deployment, panel layout, and seam orientation
• Perform pre-jointing equipment and machine checks and produce acceptable trial seams
• Weld seams with dual-track hot wedge and extrusion welders under controlled parameters
• Test seams by air-channel pressure, vacuum box, and destructive peel and shear methods
• Repair defects and document panels, seams, tests, and repairs

Course Outline

• Module 1 — Safety Legislation, Regulations, and Policy: site hazards, slopes, heat, and equipment safety
• Module 2 — Characteristics of HDPE Sheets: resin, thickness, texture, and material specifications
• Module 3 — Supply, Handling, and Installation: storage, deployment, anchorage, and weather limits
• Module 4 — Pre-Jointing Equipment and Machine Checks: wedge and extrusion welders, preheat, and trial seams
• Module 5 — Hot Wedge Welding: speed, temperature, pressure, and dual-track seams
• Module 6 — Extrusion Welding: grinding, tacking, bead placement, and detail work
• Module 7 — Seam Testing and Repair: non-destructive and destructive tests, repairs, and CQA records

Standards & References

ISO 21307:2017 and ISO 12176-1 (fusion principles for polyethylene); ASTM D3261; BS EN 13705:2004 — Welding of thermoplastics, machines and equipment for hot gas welding including extrusion welding. Geomembrane-specific references include ASTM D6392 (seam strength by thermo-fusion methods), ASTM D5820 (air-channel pressure testing of dual seams), ASTM D5641 (vacuum chamber testing), and GRI-GM13 (HDPE geomembrane specification).

Assessment & Certification

Candidate competence is evaluated through a written examination and a practical assessment in which candidates produce wedge and extrusion seams that are tested non-destructively and destructively. Successful candidates receive an IIME Certificate of Training bearing a unique verification code that can be confirmed online. The program comprises 40 contact hours (5 days).