1 in the load and driving conditions, forklift tire has a proper tire pressure, when the tire pressure is lower than the standard value driving, tire radial deformation increases, both sides produces excessive deflection and that crown on both sides of the ground, the inner sidewall compression, tension with the outer wall of the side of the tire, tire cord in produce larger deformation and alternating stress. Ang forklift accessories Billiton said periodic compression deformation, will return to speed cord of fatigue damage, the tire cord fabric layer and between the tyre and the ground relative slip increases, increased the heat generated by friction, tire temperature rise sharply, so that the tensile strength of the rubber reduce, the loose cord and local delamination, in case of barrier impact produces a flat tire. Tread pressure is not uniform, the shoulder part wear, have a "bridge" effect, fetal surface dentate or wavy. The tire pattern concave part easy to embed the road nail and the stone, cause the mechanical damage. Tire rolling resistance increased, increased fuel consumption. Experiments show that, when the tire pressure is lower than the standard value of 20% - 25%, fuel consumption increase 20%. When the tire pressure is higher than the standard value, the tire crown central grounding, the tire contact area decreases, the load on the unit area increases, the middle wear of the tire crown is increased.

II under certain load and tire pressure, speed is increased, the deformation of tire deformation frequencies, the matrix of vibration and the circumference of the tyre and lateral distortion (formation of stationary wave) increases, increases in unit time internal friction generated heat, decline in the performance of tire, even this cord layer is ruptured and the fetal surface spalling phenomenon, accelerate the tire wear and damage.

3 under the tire pressure, tire overloading make the flexure deformation increases, the cord and cord stress increases, easy cause sidewall cord broken, loose and ply delamination, carcass cord force will exceed the design allows should force and the tire ground pressure to produce the heat increased, carcass temperature increase bearing capacity reduces. The lift truck parts of the truck are worn, especially in the face of obstacles, even when a small stone, will cause the tire crown blasting. Practice has proved that traveling in turn and uneven pavement, when the tire load is over 20%, the mileage will be reduced by 35%; more than 50%, reduce 59%; more than 1 times, the reduction of more than 80%.

The high temperature can make the rubber tearing strength, elongation and hardness decreased, the rubber cord adhesion strength decreased, but also accelerate the aging of the rubber. In high temperature of the tire, especially aging tires, when slip occurred or roll over obstacles, it is easy to make tread pattern tear. Due to the aging of the rubber tire wall and produce crack and sidewall serious result of deformation of the carcass ply cord and rubber separation, once the tire local encounter sudden load is likely to burst.

Fifthly, when the tire is oil, acid and alkali corrosive substances and long time high temperature, the physical and chemical properties of tire will change, the carrying capacity is reduced greatly, use puncture easily. In addition, oil corrosion of the tire will seal gas layer massive spalling, fetal mouth small area off the rubber and tyre cord and rubber detachment phenomenon appears. Since the patch could not be compatible with the oil bearing rubber, the possibility of repairing the tire was lost even if the tire was damaged..

The extension ang forklift accessories said due to the load distribution before and after the bridge, drive wheel and steering round of the characteristics of different and pavement condition difference, the tire wear conditions inconsistent, if on both sides of the same axle not to replace the tire factory, the same size, structure, level and pattern, it will accelerate the tire wear.