The process of aging in children’s play equipment

　　The children’s amusement‑equipment industry is a relatively new sector, and currently many investors are entering the park‑development market. When operating such facilities, it is essential to ensure the safe and reliable operation of all equipment and to carry out daily routine maintenance and upkeep. Aging components should be replaced promptly, and detailed records must be kept each day. Below, we will provide a detailed analysis of the aging process of children’s amusement‑equipment parts.

　　(1) Run-in phase. The surfaces of the new friction pair exhibit a certain degree of roughness, and the actual contact area is very small. Consequently, wear is extremely rapid at the onset of run-in. As run-in progresses, the asperities on the rough surfaces are gradually worn away, the actual contact area increases, and the surface becomes smoother and more even, leading to a gradual reduction in the wear rate. Once a certain level is reached, the wear rate stabilizes, marking the end of the run-in phase. The total wear incurred during this period is referred to as initial wear.

　　The break-in period is a phase during which operators deliberately exploit the mild wear that occurs to establish conditions conducive to stable, steady‑state operation. During this stage, equipment that has not yet been broken in should adhere to guidelines such as reducing load and speed, operating under proper procedures, using low‑viscosity lubricants, and maintaining a relatively constant temperature. Additionally, to shorten the break-in period, appropriate advanced manufacturing processes may be employed to enhance equipment utilization. Upon completion of the break-in phase, the lubrication system should be cleaned, and lubricants meeting the required quality standards should be used.

　　(2) Stable Running-In Phase. This phase represents normal operating conditions. Following the running-in period, the friction surfaces undergo work hardening, and their micro‑geometric features are altered, resulting in slow, stable wear. In the later part of this phase, metal fatigue causes wear to accelerate somewhat, but operation can still continue. As the machine approaches its fatigue limit, regular, mandatory overhauls should be scheduled to prevent serious mechanical failures due to excessive wear.

　　(3) Severe wear stage. During this stage, as the surface layer of the metal essentially reaches its fatigue limit, the friction conditions undergo significant changes—such as a sharp rise in temperature, marked alterations in the surface microstructure, modifications to the microscopic geometry, increased clearances, and deteriorating lubrication conditions—which lead to a rapid increase in the wear rate, a decline in mechanical efficiency, loss of precision, and the generation of abnormal noise and vibration. Coupled with changes in the material’s mechanical properties, these factors ultimately result in component failure, necessitating repair.