Issue link: https://read.dmtmag.com/i/34500
RUN-FLAT AND ZIPPER RUPTURES Run-flat: Any tire that is known or suspected to have run at 80% or less of normal operating pressure. Normal Operating Pressure: The cold inflation pressure required to support a given load as recommended by the tire manufacturer’s data book. Zipper Rupture: This condition is a circumferential rupture in the flex zone of the sidewall. This damage is associated with underinflation and/or overloading. Any moisture that is permitted to reach ply cords will cause corrosion, which can also result in a zipper rupture. Occasionally, a tire will be flat when it arrives at the repair facility and there will be no external signs of a rupture. Note the X-ray photo below on the right reveals the broken casing ply cords. If re-inflated, this tire will experience a rapid loss of air with explosive force. Zipper ruptures can and have resulted in serious injuries and death! X-ray Photo of Broken Cords on Unruptured Casing Circumferential Rupture of Casing Ply or “Zipper Rupture” 40 MICHELIN X One Tire Maintenance ® ®