• Abrasive wear (mechanical abrasion).
• Corrosive wear (chemical reactions).
• Adhesive wear (e.g. friction welding).
• Combination of different types of wear.
  

• Abrasive additives (e.g. glass fibres, calcium carbonate, titanium oxide, master batch).
• Type and shape of raw material (e.g. ground stock, regrind, etc.)
• Corrosive additives (e.g. flame retardants)
• Higher output capacities.
• Higher screw speeds.
  

• Nitrated surface of drilled hole(s).
• Laser-hardened drilled hole(s).
• Bi-metallic barrels
• Powder metal barrel segments in accordance with the HIP ("Hot Isostatic Pressing“) process for twin screw barrels and the grooved feed of grooved feed extruders,
• Bi-metallic barrel using a centrifugal casting process for single screw or grooved feed extruders.
  

Wear protection measures for screws:

• Nitrated surface.
• Armoured surface on the external diameter of the screws and nitrated faces and core diameter using the WWP® ("WEBER Wear Protection“) process.
• Laser-hardened screw surfaces.
• Surface coating of the faces and the core diameter:
  • Chrome nitrite coating using the PVD ("Physical Vapour Deposition") process,
  • Ceramic coating (e.g. with tungsten carbide),
  • Hard chrome coating,
  • Thin layer of chrome plate,
  • Chemical nickel plating etc.