Jaw vulcanization is a highly efficient and specialized tread vulcanization and shaping process in cold retreading (pre-vulcanized tread retreading) of mining engineering vehicle tires. Its core principle is to apply uniform lateral pressure and temperature to the tire carcass with a pre-formed tread using a jaw vulcanizing machine, completing the cross-linking of the rubber layers and the shaping of the tread pattern.

Using a pre-formed tread (with complete tread pattern) that has been vulcanized at high temperature, it is bonded to the sanded old tire carcass through low-temperature vulcanization (110–120℃) and a special adhesive.

• Equipment:
  Jaw tread vulcanizing machine (hydraulic drive, jaw pressure plate, heating plate)
• Principle:
  When closed, the upper and lower jaw plates apply uniform pressure (0.8–1.2 MPa) from both sides towards the center, combined with electric/steam heating (110–120℃), ensuring thorough vulcanization and tight bonding of the buffer rubber/adhesive between the pre-made tread and the tire carcass.
• Advantages:
  Uniform pressure, precise shaping, high efficiency, suitable for large-size heavy-duty tires.

Heavy-duty engineering tires for large mining dump trucks, loaders, bulldozers, etc. (23.5R25, 29.5R25, 35/65R33, etc.) Tires with intact carcass structure and only tread wear that can be retreaded.

• Uniform pressure distribution: Avoids uneven local pressure in traditional vulcanizing tanks, reducing air bubbles and delamination.
• Authentic tread pattern: Pre-fabricated tread pattern is non-deformable and highly clear.
• High efficiency: Multi-layer mold, automatic push-pull, multiple tires can be processed in a single batch.
• Minimal carcass damage: Low temperature (110–120℃), lower than hot retreading (150–180℃), protecting carcass strength.

1. Carcass Inspection and Screening
   • Appearance + X-ray / Ultrasonic Testing: No structural damage, no broken steel wires, no delamination.
   • Wear Standard: Remaining tread ≥ 2mm
2. Carcass Pretreatment
   • Cleaning → Drying → Large Grinding / Fine grinding (exposing fresh rubber, without damaging the cords)
   • Repairing damage (≤3 places, single hole ≤35mm)
   • Applying adhesive/mortar → Drying
3. Tread bonding
   • Applying buffer rubber layer (intermediate pad rubber)
   • Centering and bonding pre-cured tread → Roller pressing for degassing and compaction
4. Jaw vulcanization (core)
   • Loading into the jaw vulcanizing machine → Closing and pressurizing (0.8–1.2 MPa)
   • Heating to 110–120℃ → Holding vulcanization for 120–180 minutes
   • Pressure holding, temperature control, degassing
5. Cooling, finishing, quality inspection
   • Natural cooling → Deburring, shoulder trimming
   • Appearance + uniformity + dynamic balance testing

• Temperature: 110–120℃ (low temperature, protecting the tire carcass)
• Pressure: 0.8–1.2 MPa (lateral uniform pressure)
• Time: 120–180 Minutes (larger specifications, longer)
• Environment: Fully vented, no bubbles

• Tire Carcass Qualified: No hidden damage
• Grinding Properly: Ra50–100μm, no contamination
• Tight Bonding: No air bubbles, accurate centering
• Precise Vulcanization: Strict control of temperature, pressure, and time
• Finished Product: No air bubbles, no delamination, clear tread pattern, bonding strength ≥8N/mm

Jaw vulcanization is the preferred process for cold retreading of mining engineering vehicle tires. With its uniform pressure, low-temperature precision, high efficiency, and stability, it allows retreaded tires to approach the performance of new tires (lifespan reaching 85%+ of new tires), while costing only 30–40% of new tires, significantly reducing mining operating costs.