Granite V-blocks are high-precision measurement tools made from natural granite material. These tools provide an ideal reference surface for inspecting instruments, precision tools, and mechanical parts, especially for high-accuracy measurements.
Extracted from deep underground granite deposits, granite V-blocks are formed over billions of years, giving them exceptional stability. They are not susceptible to deformation due to regular temperature changes. With fine-grained and hard crystalline structure, granite blocks are chosen after rigorous physical testing to ensure long-lasting precision. Being a non-metallic material, granite is free from magnetic interference and plastic deformation, which ensures that accuracy is maintained over time. Even under heavy impacts, granite V-blocks can only lose a few chips, making them highly resilient compared to cast iron or steel blocks, which are commonly used for precision measuring.
Granite V-Block Specifications and Standards
Manufacturing Standard
Granite V-blocks are made according to the JB/T8047-95 standard, commonly known as V-blocks or V-stands. They come in different configurations, including three-pocket V-blocks, single-pocket V-blocks, and five-pocket V-blocks.
Material Composition
The material used for granite V-blocks is carefully selected granite, known for its high rigidity and resistance to wear. While V-blocks made from cast iron can be divided into gray cast iron and nodular cast iron, granite V-blocks offer superior stability, making them ideal for high-precision applications. They are supplied as a pair and are primarily used in the inspection, marking, and clamping of precision shafts and other cylindrical parts.
Accuracy Levels
Granite V-blocks come in three accuracy grades: Grade 1, Grade 2, and Grade 3. The accuracy of the V-blocks is defined in terms of the parallelism and perpendicularity of their surfaces and V-grooves. These parameters ensure that the centerline of the V-groove is symmetrical and aligned with the surface, guaranteeing precise measurements.
Main Applications
Granite V-blocks are mainly used for holding and centering round workpieces like shafts, sleeves, and discs. They help to align the centerline and mark the centerline of the workpiece during inspections and machining. Typically, granite V-blocks come as a pair, with both the surface and V-grooves precision-milled to ensure accuracy.
Load Capacity
The load capacity of a granite V-block refers to how much weight it can bear without deformation. After placing the workpiece on the V-block, the block should support the weight without any noticeable deflection, maintaining its structural integrity for long-term use. The load-bearing capacity ensures that the V-block remains stable and accurate under heavy-duty operations.
Why Choose Granite V-Blocks?
High Durability & Precision – Granite offers exceptional hardness, allowing for high-precision measurements with minimal wear over time.
Non-Magnetic – Granite V-blocks are not affected by magnetic fields, making them ideal for sensitive applications.
Stable Performance – Granite V-blocks maintain their accuracy and stability under heavy loads and environmental changes, ensuring long-term reliability.
Low Maintenance – Granite V-blocks are easy to maintain, resistant to corrosion, and free from rust, offering a long service life.
Applications of Granite V-Blocks
Precision measurement and inspection
Tool calibration
Mechanical part alignment and marking
CNC machine setup and fixture
Metrology and research laboratories
Granite V-blocks are essential for professionals in precision engineering, manufacturing, and mechanical testing. Their ability to maintain consistent accuracy under extreme conditions makes them a preferred choice in high-precision industries.