Basically, there are two systems used to retread a tire, Mold Cure and Pre Cure.

The reason both systems exist is because of the economics of operating a retread plant and have nothing to do with the quality of the finished product. Each system has unique advantages, but both systems produce equally good retreaded tires. 

The initial steps in retreading a tire are the same regardless of which retreading system is used. These steps are: 

Primary Inspection

Each tire received in a retread plant is subjected to a very rigorous visual inspection. Inspectors may be assisted by the use of various non-destructive sophisticated inspection equipment available in the retread industry. Each tire is registered on Seaport’s Retread Production software, which will track each tire throughout the production process.

 

 

Buffing Station

 

After inspection, tires have the old tread mechanically removed on high speed buffers. Today's buffers are extremely accurate and will remove the proper amount of old rubber while truing the tire to an exact specified diameter and radius. Seaport’s buffers are computer upgraded with each manufacturer’s specification. Each tire is buffed to industry standards to assure a high quality product.

Rubber Application

Application of new rubber in the tread area. Here is where the systems differ.

 

Pre-cure Tread Builder and Cushion Extruder

 

Pre-cure Curing Chamber

In the pre-cure system, the tread rubber has already been vulcanized with the new tread design. The buffed tire has a thin layer of cushion gum wrapped around the tread area and the pre-cured tread is then applied. The cushion gum serves to bond the pre-cured tread to the tire. The tire is then placed in a curing chamber and the pre-cured tread becomes adhered to the tire through a vulcanizing process very similar to that used in new tire construction.

Computerized Mold cure Rubber Extruder

In the mold cure system, unvulcanized tread rubber is applied to the buffed tire. The tire is then placed into a rigid mold, which contains the tread design in the tread area. The mold is heated and the rubber in the tread area vulcanizes and adheres to the tire with the new tread design molded in. Again, this vulcanization process is very similar to that used in new tire construction. Both systems require a combination of time, heat and pressure to create the vulcanization of the new rubber to the tread area of the tire.

Rigid Molds

Final Inspection

The retreaded tire is subjected to a final inspection. This inspection insures that only tires that meet industry quality standards are allowed to leave the retread plant. The finalized tire is registered in the computer and transferred electronically to Seaport’s shipping department. The completed tire is then ready to return to full service and a second (or third) life as a safe and economical alternative to high priced new tires.