In high-end equipment such as semiconductor optical platforms, ultra-precision laser processing and coordinate measuring machines, granite air bearing bases rely on thin air films to achieve frictionless motion. The long-term stability of the air film directly determines the durability of equipment positioning accuracy. Many equipment buyers raise the same question: after years of continuous operation, will the air film of the base gradually become unstable, resulting in slide jitter, fluctuating load capacity and positioning drift? The answer is not absolute. The degradation of air film stability is not an inherent property of the product. Instead, it is determined jointly by materials, craftsmanship, surface condition and working condition maintenance. The air film of low-quality air bearing bases deteriorates rapidly after commissioning, while ZHHIMG granite air bearing bases adopt multi-dimensional long-term stability design to effectively slow down or avoid air film attenuation.
The degradation of air film stability usually stems from four categories: substrate deformation, wear of air outlet surface, microhole blockage and slow release of residual stress. The stone bases adopted by many manufacturers have insufficiently released internal stress. Under repeated ambient temperature cycles, the substrate undergoes slow creep, causing micro-deformation of the air outlet reference surface and offset of the relative height of microhole openings, which further unbalances the distribution of air film thickness. Some products have insufficient grinding grade on the air outlet surface. Tiny pits and burrs exist on the surface. Under continuous airflow scouring, the surface morphology gradually changes and destroys the original uniform air outlet state. In addition, poor machining quality of microhole arrays causes chipping at hole openings. Long-term airflow disturbance amplifies local turbulence, and the pressure uniformity of the air film continuously deteriorates over time.
ZHHIMG carries out preventive design for long-term service conditions at the product manufacturing stage. First of all, high-density black granite substrate is selected. Its internal crystal structure is dense with extremely low creep effect, and no continuous slow deformation occurs under repeated temperature cycles. Long-period aging treatment is implemented at the blank stage to fully release the internal machining stress of the stone, preventing the finished product from changing the profile of the air outlet surface due to slow stress release during years of use, and fundamentally eliminating air film offset caused by reference surface deformation.
For the long-term retention of air outlet surface and microhole openings, submicron progressive grinding technology is adopted to ensure all microhole outlets are coplanar with the substrate reference surface, with smooth and intact hole edges. The smooth and continuous air outlet surface reduces surface erosion caused by high-speed airflow and prevents the deterioration of hole opening morphology caused by long-term airflow scouring. The regular and smooth inner walls of microholes reduce the probability of dust adhesion, lower the risk of gradual microhole blockage during long-term operation, and maintain the long-term consistency of flow at each air outlet point.
Besides material and finishing processes, the long-term stability of air film also relies on endurance simulation verification before delivery. After machining, products will undergo long-duration continuous air floating aging tests under constant-temperature and shock-proof metrology environment. The air film pressure distribution, bearing capacity fluctuation and linearity of slide movement are continuously monitored. Hidden defects that only appear after long-term operation are screened in advance. Only products passing endurance verification will be delivered. Meanwhile, a complete working condition adaptation system is established. Matching cleaning protection schemes are provided for different application environments to reduce dust and oil from invading air-floating microholes and further extend the stable service life of the air film. 
Naturally, every ultra-precision component has its application boundary. If the equipment runs continuously in harsh environments with heavy dust, oil pollution and drastic temperature fluctuations without basic cleaning maintenance, even high-quality granite air bearing bases will suffer gradual air film performance degradation. ZHHIMG provides supporting operation guidelines upon delivery to help customers build basic operating conditions with clean air supply and constant ambient temperature, so as to retain the original air film performance to the maximum extent.
Compared with the pain point that air film fluctuation occurs within a short period for ordinary air bearing bases on the market, ZHHIMG granite air bearing bases greatly extend the stable service cycle of air film by adopting low-creep substrate, full stress relief process, coplanar ultra-precision grinding of hole openings and pre-delivery endurance testing. In rigorous scenarios such as semiconductor XY motion platforms, precision metrology and femtosecond laser equipment, it can maintain uniform and stable air film state for a long time and continuously guarantee the motion accuracy of ultra-precision equipment.
Post time: Oct-09-2026