Retreading Tires: Pre-Cure VS Remold Curing
When it comes to retreading tires, there are currently two popular curing options known as Pre-Cure and Mold Cure. Each retreading method can offer a quality remanufactured tire with similar processes but have fundamental differences in their curing process.
Similarities:
Both Pre-Cure and Mold Cure retreading start with a comparable process undertaking inspection, buffing, adding new rubber*, balancing and final inspection. The differences between the two processes occur during the building and curing phase.
Differences Between Remold Retreading & Pre-Cure Retreading
Remold Retreading: (TreadWright Process)
Unlike the pre-cure process, a remolded tire is the closest retread you can get to a brand new tire. During the building process, a remolded retread tire is wrapped with unvulcanized industrial grade rubber to the crown and shoulder of each tire by an Orbitread machine. The sidewalls are then given a new layer of sidewall veneer, which brings the entire tire back to a new condition (common in Warden, Guard Dog and Claw brands). All TW tires are balanced with a Corghi Balancer prior to remolding.
The next step in our manufacturing process is to cure the tire. Each rebuilt casing is individually placed in its corresponding mold/press (size and model) and cured for approximately 60 minutes. When the mold is closed and the tire body inflated to the proper pressure, the swelling of the casing conforms the uncured material to the mold, forming the tread design. Heat and pressure are then applied to a specific period of time to accomplish curing. The tire is now remanufactured back to a completely new condition. Our presses and molds use the same mold curing process that is standard in all new tire manufacturing plants.
Remold Retreading Additional Notes:
- Offers Dedicated time, pressure and heat to each individual tire that is built unlike Pre - Cure, which cures multiple tires at once.
- Remolding retreads are suitable for all tire applications, including car and aircraft tires.
- Hot retreading also allows extensive repairs to be carried out on the tire carcass (e.g. belt replacement).
- Even bias-ply carcasses can undergo hot retreading without any problem
- A separate mold is required for each tread and size. This requires a high level of investment in a range of molds, which will be needed to be regularly updated.
- The production process needs to be designed for large numbers of tires. This calls for a central production workshop, an extended customer area and therefore brings with it relatively high logistics costs.
Pre Cure Retreading:
During the Pre-Cure building phase, the inspected/buffed casing will add a thin layer of cushion gum, which acts as an adherent between the vulcanized pre-cured tread and the tire. After the cushion gum has been administrated the retreader will add the vulcanized pre-cured tread pattern over top splicing the ends and holding them together with staples before entering the curing chamber. The tire is then placed in a pressurized heated chamber by air produced through electricity, steam or hot liquid such as oil. The prepared casing, with the new rubber in place, is put into the chamber where pressure and temperature, applied over the correct length of time, cure the cushion gum layer and bond the tread to the tire.
Pre-Cure Notes:
- Multiple Tires are usually cured at the same time in one chamber
- The barrier to entry is easier with less of an investment required on the part of the retreading plant (no expensive molds) along with lower follow-up costs since it is the material supplier who updates the range of molds.
- A wide range of tread types is available, allowing the optimum tread to be selected for the tire application
- Pre-cure retreading requires high-quality carcasses.
* Retreaders can use different Rubber Suppliers. TreadWright only uses industrial grade rubber compound with higher wear characteristics.
