Many people assume that the production of precision granite components only involves simple stone cutting followed by surface polishing. However, to achieve micron or even nanometer-level accuracy, granite bases, beams, square boxes and substrates used in high-end equipment for semiconductors, optical measurement and coordinate measuring machines must go through a set of exclusive special procedures, which differ greatly from common stone machining. Ordinary stone processing only focuses on appearance and basic dimensions, while the core objective of the full process for precision granite components is to continuously release internal stone stress and lock the geometric shape in a stable state, preventing creep deformation during long-term service. ZHHIMG Group (ZHHIMG®) manufactures high-stability precision granite components relying on this customized system of special procedures.
Non-destructive raw blank inspection and directional material extraction is the first special procedure different from ordinary stone processing. Conventional blank cutting only checks external dimensions and does not explore the interior of stone. During geological formation and mining blasting, granite may contain invisible microcracks, mineral segregation and impurity interlayers. These hidden defects will gradually appear during later processing or under load, resulting in surface deformation. ZHHIMG uses non-destructive testing to screen raw blanks and locate defective zones inside. Combined with the position of the finished reference surface, engineers plan cutting directions, so that the finished benchmark surface falls in regions with uniform mineral grains and no hidden damage. Directional material extraction can avoid anisotropic deformation caused by grain orientation and reduce risks of later accuracy drift starting from raw materials.
Multi-round intermittent stress aging is the core stabilization special process for precision granite. Every cutting, drilling and grooving operation on stone introduces new residual surface stress. Continuous machining without standing will let stress release slowly after product delivery and ruin finished precision. ZHHIMG adopts intermittent aging of “machining – standing – re-machining”, rather than forming the part in one pass. Static stress relief is performed after rough cutting; another constant-temperature standing is arranged after rough milling, drilling and grooving; further storage follows semi-finish grinding to release grinding residual stress. The aging period is not fixed and will be dynamically adjusted according to component size, thickness and hole density. This procedure actively releases most residual stress before delivery, stabilizing the geometric state of finished parts.
Low-impact layered cutting forming is a special procedure for granite structural machining. Granite is brittle. High-power one-time cutting easily triggers impact cracks and surface stress. For mounting holes, cable grooves and weight-reduction cavities on bases, beams and square boxes, ZHHIMG abandons deep single-pass cutting and uses diamond tools for layered micro-cutting. Only a small amount of material is removed each pass to control cutting heat and mechanical shock and protect the substrate from microcracks. When dealing with dense hole arrays, deep grooves and counterbore holes and other complex features, tool paths are optimized to balance stress distribution across stone and avoid local stress concentration. This procedure balances structural forming and substrate stability and prevents long-term deformation risks caused by processing damage.
Composite grinding under constant-temperature and vibration-isolated environment is the special finishing procedure to obtain ultra-high reference surfaces. Ordinary polishing has no strict control over temperature variation and vibration. Temperature gradients and ground micro-vibration will directly leave ripple errors on plate surfaces. ZHHIMG carries out grinding in constant-temperature shockproof workshops, split into CNC rough & fine grinding and manual nano finishing. Large CNC grinders shape the overall contour and eliminate long-wave undulations. Then experienced technicians conduct local manual fine lapping to correct micron and nanometer contour deviations. Cooling conditions are fully controlled during grinding to restrain local thermal deformation induced by friction heat, eventually delivering reference surfaces with excellent flatness. Products will not be shipped right after grinding; components stay in constant-temperature environment to check shape stability.
Unified calibration of feature geometric reference chain is a metrology supporting procedure unique to precision granite. Ordinary stone machining separately inspects individual dimensions. For precision granite components, all holes, grooves and reference edges must build a unified geometric relationship with the main reference surface. After grinding, ZHHIMG uses laser interferometers, high-precision levels and inductive micrometers, taking the main reference plane as the origin, to inspect hole position tolerance, groove straightness, perpendicularity and parallelism of adjacent surfaces and all other geometric tolerances. If deviation exists between features and main benchmark, micro compensation correction will be performed to ensure all assembly benchmarks of the whole component match each other. This procedure guarantees seamless alignment of guide rails, sensors and motion modules during equipment assembly without reference misalignment.
Surface passivation and sealing protection serves as a special finishing treatment for finished products. Granite has inherent micro-pores which easily absorb moisture and oil. Moisture absorption leads to tiny expansion and changes reference precision. ZHHIMG applies passivation sealing treatment on precision reference surfaces. Without altering original geometric accuracy and roughness, the process seals micro-pores on the stone surface. Treated surfaces resist moisture absorption and contaminant adhesion, reduce micro deformation induced by temperature and humidity fluctuation and cut dust shedding, suitable for clean working conditions such as semiconductor and optical inspection. Unlike common paint coating, this treatment will not cover reference surfaces, will not change original metrology accuracy and will not interfere with probes and sensors. 
Final static re-inspection and benchmark archiving is the last special procedure before delivery. After machining, grinding and protection, components still need long standing in constant-temperature environment to simulate long-term stable status. Full-area recheck of flatness and geometric tolerances will be conducted again. Data is compared with previous measurements to confirm accuracy no longer drifts. Components are only approved after repeated stable measurement results. Each precision granite component is equipped with exclusive metrology files storing all measured data with traceable values, convenient for customer equipment acceptance and periodic benchmark recheck.
In summary, manufacturing precision granite components is not a simple assembly line of cutting and polishing. Non-destructive blank screening, intermittent stress aging, layered low-impact cutting, constant-temperature composite grinding, unified benchmark calibration, micro-pore sealing protection and final static re-inspection form a coordinated sequence of special procedures. Their core purpose is locking geometric accuracy and restraining long-term deformation. With this full set of special process systems, ZHHIMG Group continuously supplies high-stability precision granite components for semiconductor equipment, optical inspection, CMM measurement and laser processing machines.
Post time: Oct-13-2026