① Under certain load and driving conditions, the tire of the forklift has a suitable tire pressure. When the tire pressure is lower than the standard value, the radial deformation of the tire increases and excessive deflection occurs on both sides, so that the crown is grounded , The inner wall of the sidewall is compressed, and the outer wall of the sidewall is tensioned, and the cord in the tire body generates large deformation and alternating stress. Periodic compression deformation will cause fatigue damage of the speed-return cord, increasing the relative slip between the tire ply and the tire and the ground, the heat generated by friction increases, the tire temperature rises sharply, and the tensile strength of the rubber decreases , The cord is loose and partially delaminated, and a flat tire will be generated when an obstacle is impacted. The uneven pressure on the tread causes serious wear on the shoulder portion, resulting in a "bridge effect", and the tread is toothed or wavy. Tire pattern recesses are easily embedded in road nails and stones, causing mechanical damage. The rolling resistance of the carcass increases and the fuel consumption increases. Tests have shown that when the tire pressure is below 20% -25% of the standard value, fuel consumption increases by 20%. When the tire pressure is higher than the standard value, the center of the crown is grounded, the area of contact between the tire and the road surface is reduced, the load per unit area is increased, and the wear on the middle of the crown is increased. The tire cord is excessively stretched, the stress of the carcass cord is increased, and the fatigue process of the cord is accelerated, causing the cord to break, causing the tire to puncture at an early stage.
②Under a certain load and tire pressure, the speed of the vehicle increases, and the frequency of deformation of the tire, the vibration of the carcass, and the torsional deformation of the tire circumference and side (formation of static waves) increase accordingly. The working performance of the tire is reduced, and even the ply rupture and tread peeling phenomenon occur, which accelerates the wear and damage of the tire.
③Under a certain tire pressure, the overload of the tire increases the deflection of the tire, and the stress of the cord and cord increases. Exceeding the design allowable stress and tire ground pressure, the heat generated increases, the temperature of the carcass rises, and the load carrying capacity decreases. At the same time, the wear caused by the contact between the shoulder and the ground, especially when encountering obstacles, even a small stone can cause the crown to burst. Practice has proved that in the case of turning and uneven roads, when the tire load exceeds 20%, the mileage will be shortened by 35%; when it exceeds 50%, it will be shortened by 59%; when it exceeds 1 times, it will be shortened by more than 80%.
④ Road conditions also have a great influence on the service life of the tires, which affects the friction between the tires and the ground and the dynamic load on the tires.
⑤ High temperature will reduce the tear strength, elongation and hardness of the rubber, reduce the adhesion strength between the rubber and the cord, and also accelerate the aging of the rubber. For tires under high temperature, especially aging tires, when the sideslip or rolling over obstacles, it is easy to tear the crown pattern. Due to cracks in the aging of the sidewall rubber and severe deformation of the sidewall, the carcass layer cords are separated from the rubber. Once the tire locally encounters a sudden load, it is likely to burst.
⑥When the tire is corroded by grease, acid and alkali substances and the high temperature for a long time, the physical and chemical properties of the tire will change, the carrying capacity will be greatly reduced, and the tire will be very puncture during use. In addition, tires corroded by oil will suffer from flaking of the air seal layer, small areas of rubber falling off the tire bead, and carcass cords and rubber detachment. Since the patch cannot be compatible with oil-containing rubber, even if the damaged wound of the tire is small, the possibility of repair is lost.
⑦Due to the different load distribution of the front and rear axles, the different working characteristics of the driving wheels and steering wheels, and the difference in road conditions, the wear of each tire is inconsistent. Tires will accelerate tire wear.
⑧During use, if the tires are not uniformly loaded and replaced regularly, resulting in uneven load on the tires, tire wear will also be accelerated.
