ContiLifeCycle 10-Step Process

The first step of the ContiLifeCycle process involves a thorough inspection of the tire to determine if it suitable for retreading through visual and non-destructive inspection. A technician will look for any damage or issues that may affect the retreading process or tire tire performance afterwards.

In the second step of the ContiLifeCycle process, the casing is investigated for any trapped air or potential separations, with special attention given to the belt edge and location underneath previous repairs. The tire is then loaded into the shearography machine where vacuum pressure is applied to the casing.

After shearography, the tire goes through buffing to remove the old tread. The technician determines the tread width and the radius of the casing and uses a computer-controlled program to precisely buff the contours, ensuring consistent under-tread thickness.

In the fourth step of the ContiLifeCycle process, skiving is used to find the depth of the tire injuries and to remove any debris, loose wire ends, and rust. A rotary tool is used to remove the debris and clean up injuries with the least amount of damage to the casing.

Following the skiving station, casing damage or punctures found during the inspection are professionally repaired. Specialized tools such as reams, scrapers, rasps, wire wheels, and rollers are used to remove any damages and prepare the casing for repairs. Once the surface is prepared, patches and repair material are applied to strengthen weak spots.

In the sixth step of the ContiLifeCycle process, uncured cushion gum is adhered to the casing prior to application of the precured tread. Between 1.5 and 2 mm of cushion is extruded onto the casing and a smear is created on the end of the extrusion to ensure uniformity around the casing.

After extruding, tread rubber is attached to the tire casing and cushion gum. A machine unrolls the tread and centered on the casing with guided precision. The tread is overlapped between 2-4 mm at the ends and a splice cushion is applied to the leading edge of the tread. The splice is pressed together to remove air voids, then stapled together.

In this step, the tire receives an outer and inner envelop to provide the mechanical pressure against the casing and tread needed during the curing process. The casing is tested for proper envelope sealing using a vacuum. Any leaks are fixed and the tested envelope is capped before staging in the autoclave.

After the tire is enveloped, the tire undergoes a curing process to vulcanize the new tread with the casing. The vulcanization process requires specific temperature and pressure conditions, along with the right duration of time to create a chemical reaction with the cushion gum and other uncured rubbers to create the finished tire.

Once the curing process is complete, the retreaded tire is inspected to ensure the tread is securely bonded to the casing. It undergoes an inflation test designed to ensure safety of the retread in a controlled environment. A 7-point visual inspection concludes the process, making sure there are no defects or imperfections that could affect performance or safety.