A chemical plant reported that a Heli CPD25 forklift had a slow air leak in the front left tire, requiring reinflation every 3 days. The tire was relatively new (only 2 months old).
The technician removed the wheel and deflated the tire. He inspected the "Valve Stem," which was good. He broke the "Bead Seal" (the contact between the tire and the rim). He found the "Rim Flange" (the edge of the metal wheel) was severely corroded with white rust (oxidation).
The chemical environment (fertilizers/cleaners) had corroded the paint on the rim. The rust created a rough, uneven surface. The tire bead (the inner edge of the tire) could not seal tightly against this rough surface. Air leaked through the microscopic gaps in the rust.
The repair involved using a "Wire Brush Wheel" on an angle grinder to remove all rust from the rim flange. The rim was then painted with an "Epoxy Anti-Corrosion Coating." A new tire was mounted. The technician applied a thin layer of "Tire Bead Sealer" (a rubber-based glue) to the rim before inflating. The tire was inflated to 14 bar (solid tire pressure) to seat the bead firmly. This restored the airtight seal, eliminating the daily reinflation requirement.
