{"id":3305,"date":"2026-08-31T09:28:51","date_gmt":"2026-08-31T01:28:51","guid":{"rendered":"https:\/\/jtlcnc.com\/?p=3305"},"modified":"2026-08-31T09:28:55","modified_gmt":"2026-08-31T01:28:55","slug":"what-are-the-factors-affecting-the-processing-accuracy-of-granite-stone","status":"publish","type":"post","link":"https:\/\/jtlcnc.com\/fr\/2026\/08\/31\/what-are-the-factors-affecting-the-processing-accuracy-of-granite-stone\/","title":{"rendered":"Quels sont les facteurs qui influent sur la pr\u00e9cision de l'usinage du granit ?"},"content":{"rendered":"

Core Factors Affecting the Machining Precision of Granite (Jinan Blue) Equipment Bases<\/h1>\n\n\n\n

Divided into six major areas: raw material itself, stress and aging, machining process, grinding process, environmental conditions, and post-transportation\/installation<\/strong>. For 00\/000-grade precision bases, every factor directly affects flatness and parallelism.<\/p>\n\n\n\n

I. Stone Raw Material Factors<\/h2>\n\n\n\n
    \n
  1. Ore Material Grade<\/strong>
    Premium Jinan Blue (gabbro) has fine grains and a uniform structure; ordinary black granite has uneven grains, cracks, and mica inclusions. Even if ground, it will undergo slight deformation later, making it difficult to stably achieve 000-grade precision.<\/li>\n\n\n\n
  2. Internal Cracks, Pores, and Mineral Impurities<\/strong>
    Small dark cracks are hard to detect during machining. After grinding and cutting, stress is released, causing local warping; mica-rich areas are prone to local wear, resulting in failed flatness.<\/li>\n\n\n\n
  3. Block Extraction Direction<\/strong>
    The direction of rock layer texture is critical. The base surface should avoid the bedding direction as much as possible; otherwise, it is prone to warping and deformation due to temperature and stress.<\/li>\n<\/ol>\n\n\n\n

    II. Internal Stress (The most easily overlooked, the number one killer of precision bases)<\/h2>\n\n\n\n

    Granite mining and large-saw cutting generate a large amount of residual stress.<\/p>\n\n\n\n

      \n
    1. Insufficient Natural Aging<\/strong>: If the raw blocks or semi-finished products are not allowed to rest long enough to release stress, they may pass fine grinding but warp on their own after a period of time, causing precision to drift.<\/li>\n<\/ol>\n\n\n\n
      \n

      000-grade bases typically require semi-finished products to rest for 30-45 days; high-requirement ones undergo secondary aging.<\/p>\n<\/blockquote>\n\n\n\n

        \n
      1. Surface Stress from Cutting Impact<\/strong>: The surface layer of large-saw cutting contains a stress layer. If fine grinding is performed directly, it will rebound and deform later.<\/li>\n\n\n\n
      2. Local Stress from Steel Inserts and Drilling<\/strong>: Drilling and pressing steel inserts create local compressive stress, causing the plate surface to bulge slightly.<\/li>\n<\/ol>\n\n\n\n

        III. Machining Equipment and Process<\/h2>\n\n\n\n
          \n
        1. Cutting Equipment Precision<\/strong>: If the large saw or gantry saw has poor precision, the blank plate itself will be warped. Subsequent grinding will need to remove a large amount of material, increasing the risk of deformation.<\/li>\n\n\n\n
        2. Milling and Slotting<\/strong>: CNC gantry milling for T-slots and steps with unreasonable feed rates will generate local compressive stress.<\/li>\n\n\n\n
        3. Grinding and Polishing Process<\/strong><\/li>\n<\/ol>\n\n\n\n
            \n
          • Rough grinding \u2192 Semi-fine grinding \u2192 Fine grinding \u2192 Ultra-fine grinding. Skipping steps and going directly to fine grinding cannot eliminate previous waviness;<\/li>\n\n\n\n
          • If the grinding disc is worn or not level, the workpiece will exhibit central convexity or concavity;<\/li>\n\n\n\n
          • Excessive grinding pressure: The plate undergoes elastic deformation under pressure. It may pass inspection, but will rebound out of tolerance once the pressure is released.<\/li>\n<\/ul>\n\n\n\n
            \n

            Point cl\u00e9 : Large-sized granite plates cannot be ground under heavy pressure<\/strong>, and 000-grade precision requires extremely high standards for grinding tooling.<\/p>\n<\/blockquote>\n\n\n\n

            IV. Machining \/ Inspection Environmental Temperature (Decisive factor for 000-grade)<\/h2>\n\n\n\n

            Although granite has a low coefficient of thermal expansion, large-sized bases are still sensitive to temperature differences.<\/p>\n\n\n\n

              \n
            1. Non-constant temperature in the workshop<\/strong>: Temperature differences between day and night cause the plate to expand and contract, distorting grinding and inspection data.<\/li>\n<\/ol>\n\n\n\n
              \n

              000-grade verification standard environment: 20\u00b0C \u00b1 2\u00b0C, constant temperature workshop, workpiece fully isothermal, placed for at least 4-8 hours before inspection<\/strong>.<\/p>\n<\/blockquote>\n\n\n\n

                \n
              1. Direct sunlight, proximity to doors\/windows\/vents<\/strong>: Local temperature unevenness causes the plate surface to warp.<\/li>\n<\/ol>\n\n\n\n

                V. Tooling, Clamping, and Handling<\/h2>\n\n\n\n
                  \n
                1. Unreasonable support during machining: Incorrect three-point support or uneven force distribution in multi-point support causes elastic bending of the plate; when the workpiece is removed after grinding, it rebounds, directly exceeding flatness tolerances.<\/li>\n<\/ol>\n\n\n\n
                  \n

                  Granite surface plate machining and inspection must strictly follow the three-point support principle<\/strong>.<\/p>\n<\/blockquote>\n\n\n\n

                    \n
                  1. Lifting and handling: Hard contact with wire ropes and single-point loading generate hidden micro-cracks, leading to gradual deformation over time; lifting large plates from a single point is strictly prohibited.<\/li>\n\n\n\n
                  2. Stacking of semi-finished products: They must not be leaned against surfaces or stacked with local parts suspended, as this will cause plastic creep deformation.<\/li>\n<\/ol>\n\n\n\n

                    VI. Post-use Environment (Passed factory inspection, but accuracy lost at the customer site)<\/h2>\n\n\n\n
                      \n
                    1. Large temperature differences at the customer site, or direct sunlight hitting the equipment base;<\/li>\n\n\n\n
                    2. Uneven foundation of the base, causing local suspension and bending of the base under gravity;<\/li>\n\n\n\n
                    3. Forced hard adjustment or prying of the base leveling feet, causing deformation of the plate.<\/li>\n<\/ol>\n\n\n\n
                      \"\"<\/figure>","protected":false},"excerpt":{"rendered":"

                      Core Factors Affecting the Machining Precision of Granite (Jinan Blue) Equipment Bases Divided into six major areas: raw material itself, stress and aging, machining process, grinding process, environmental conditions, and post-transportation\/installation. For 00\/000-grade precision bases, every factor directly affects flatness and parallelism. I. Stone Raw Material Factors II. Internal Stress (The most easily overlooked, the…<\/p>","protected":false},"author":1,"featured_media":3316,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"","_seopress_redirections_param":"","_seopress_redirections_type":0,"_seopress_analysis_target_kw":"","_kad_blocks_custom_css":"","_kad_blocks_head_custom_js":"","_kad_blocks_body_custom_js":"","_kad_blocks_footer_custom_js":"","_kadence_starter_templates_imported_post":false,"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[35],"tags":[],"class_list":["post-3305","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"taxonomy_info":{"category":[{"value":35,"label":"NEWS"}]},"featured_image_src_large":["https:\/\/jtlcnc.com\/wp-content\/uploads\/2026\/08\/d-1024x714.png",1024,714,true],"author_info":{"display_name":"jinxing6611@gmail.com","author_link":"https:\/\/jtlcnc.com\/fr\/author\/jtlcnc\/"},"comment_info":0,"category_info":[{"term_id":35,"name":"NEWS","slug":"news","term_group":0,"term_taxonomy_id":35,"taxonomy":"category","description":"","parent":0,"count":361,"filter":"raw","cat_ID":35,"category_count":361,"category_description":"","cat_name":"NEWS","category_nicename":"news","category_parent":0}],"tag_info":false,"_links":{"self":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts\/3305","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/comments?post=3305"}],"version-history":[{"count":2,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts\/3305\/revisions"}],"predecessor-version":[{"id":3317,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/posts\/3305\/revisions\/3317"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/media\/3316"}],"wp:attachment":[{"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/media?parent=3305"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/categories?post=3305"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jtlcnc.com\/fr\/wp-json\/wp\/v2\/tags?post=3305"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}