a. Surface Preparation

• Ensure the base surface is clean, dry, and level
• Remove dust, oil, and sharp objects
• For lining work, the surface should be smooth to avoid punctures

b. Cutting & Shaping

• Cut using circular saw, jigsaw, or CNC machine
• Use sharp tools to avoid rough edges
• Allow margin for thermal expansion

c. Joining Methods

1. Welding (Most Common)

• Hot air welding
• Butt welding
• Extrusion welding
  

2. Mechanical Fastening

• Screws, bolts, or rivets
• Use oversized holes to allow expansion
• Add washers to distribute load

3. Adhesive Bonding (Limited Use)

• Not very effective due to low surface energy
• Special adhesives required

d. Fixing & Support

• Provide proper support frame or backing
• Avoid large unsupported spans
• Use clamps or anchors where required

e. Thermal Expansion Consideration

• HDPE expands with temperature
• Always leave expansion gaps (3–5 mm per meter)

f. Safety During Installation

• Use protective gloves and goggles
• Maintain proper welding temperature
• Ensure ventilation during welding

2. Maintenance of HDPE Sheet

a. Regular Cleaning

• Clean with water and mild detergent
• Avoid harsh chemicals (if not compatible)
• Smooth surface makes cleaning easy

b. Inspection

• Check for:
  • Cracks or deformation
  • Joint/weld integrity
  • Surface wear

c. Repair Methods

• Minor damage: plastic welding repair
• Deep cracks: patch welding or replacement
• Loose fasteners: tighten or replace

d. UV Protection

• Use UV-stabilized sheets for outdoor use
• Apply covers or coatings if required

e. Load Management

• Avoid excessive load or pressure
• Ensure even load distribution

f. Temperature Care

• Avoid continuous exposure above 80°C
• Prevent direct contact with high heat sources