Precision Granite Straight Ruler Used in AOI and X-ray Inspection Machines

Our granite straight ruler adopts high-density black granite with density of 3100kg/m³. Compared with metal gauges prone to thermal expansion and marble substitutes with loose texture, this material features ultra-low thermal deformation, strong vibration resistance and stable geometric dimension. During long-time continuous operation of AOI and X-ray equipment, the straight ruler maintains constant linearity, avoiding imaging deviation and misjudgment of PCB hidden defects. ZHHIMG strictly rejects low-grade marble raw materials to prevent hidden risks for inspection equipment manufacturers.

All granite straight rulers are finished by senior craftsmen with over 30 years of hand-lapping experience. Workers can precisely control micrometer-level removal volume, ensuring excellent straightness. The surface achieves ultra-low roughness, suitable for linear guide calibration, camera mounting benchmark and motion platform leveling of AOI and X-ray equipment. Our technicians master DIN, ASME, JIS, GB and other international metrology standards to guarantee products comply with global electronic manufacturing specifications.

Products used for optical inspection equipment are processed and inspected in our 10,000 ㎡ constant temperature & humidity workshop. The workshop floor adopts thickened anti-vibration concrete and surrounding shock-absorbing trenches, equipped with silent travelling cranes to avoid external vibration interference in the finishing stage. This production environment simulates the high-standard workshop environment of semiconductor and PCB factories, making the granite ruler adapt to long-term stable operation inside precision inspection equipment.

Each finished granite straight ruler undergoes comprehensive testing with internationally famous inspection instruments including Mahr dial gauges, Mitutoyo roughness testers, WYLER electronic levels and Renishaw laser interferometers. All testing equipment holds official calibration certificates traceable to national metrology institutes. When used as a reference standard for AOI and X-ray machine periodic calibration, our rulers can provide credible, traceable measurement benchmarks for equipment manufacturers and end users.

ZHHIMG supports flexible size customization for granite straight rulers. The maximum processing length reaches 20 meters, covering small desktop AOI equipment to large-format X-ray inspection machines. We coordinate with equipment designers to optimize installation holes, positioning surfaces and load-bearing structure. Apart from standard measuring rulers, we provide integrated customized solutions for optical inspection machinery manufacturers.

ZHHIMG is the only manufacturer in this sector owning ISO9001, ISO14001, ISO45001 and CE certifications simultaneously. More than 20 international patents and trademarks have been registered in EU, United States and Southeast Asia. We maintain long-term technical exchanges with well-known universities and metrology institutions worldwide. At present, many global suppliers of AOI and X-ray inspection equipment have adopted ZHHIMG granite measuring components, including several Fortune Global 500 partners in electronics industry.

Benefiting from natural granite’s wear resistance, corrosion resistance and stable physical performance, our straight rulers keep precision for decades under normal use. Compared with metal measuring tools which require frequent re-calibration, they effectively lower the after-sales maintenance cost of AOI and X-ray equipment and reduce downtime caused by repeated precision correction, creating long-term economic benefits for equipment manufacturers and terminal factories.