{"id":1983,"date":"2026-03-04T08:54:22","date_gmt":"2026-03-04T00:54:22","guid":{"rendered":"https:\/\/jtlcnc.com\/?p=1983"},"modified":"2026-03-04T08:54:25","modified_gmt":"2026-03-04T00:54:25","slug":"granite-slab-grade-ensure-the-accuracy-of-precision-measurement","status":"publish","type":"post","link":"https:\/\/jtlcnc.com\/es\/2026\/03\/04\/granite-slab-grade-ensure-the-accuracy-of-precision-measurement\/","title":{"rendered":"Grado de la losa de granito: Garantice la exactitud de la medici\u00f3n de precisi\u00f3n"},"content":{"rendered":"

The precision grade of granite flat plates is the core guarantee for the accuracy of precise measurements. The grade classification is centered on flatness tolerance, following the national standards GB\/T 20428-2006 and JJG 117-2013. The mainstream grades are 000, 00, 0, and 1. Grade 000 is used for higher precision scenarios, 00\/0 grades for general precision measurement, and Grade 1 for typical workshop applications.
I. Precision Grades and Flatness Tolerance (Core Standards)
Flatness tolerance varies with the diagonal length d (mm). The general formula is:
Flatness Tolerance = k \u00d7 (1 + d\/1000) \u03bcm
where k (grade coefficient) is: 000 grade = 1; 00 grade = 2; 0 grade = 4; 1 grade = 8.
Common specifications flatness tolerance (\u03bcm, at 20\u2103 standard environment):
| Specification (mm) | Diagonal d (mm) | 000 Grade | 00 Grade | 0 Grade | 1 Grade |
| 300\u00d7300 | 424 | 1.4 | 2.8 | 5.7 | 11.4 |
| 500\u00d7500 | 707 | 1.7 | 3.4 | 6.8 | 13.6 |
| 1000\u00d71000 | 1414 | 2.4 | 4.8 | 9.7 | 19.4 |
| 1500\u00d71000 | 1803 | 2.8 | 5.6 | 11.2 | 22.4 |
| 2000\u00d71500 | 2500 | 3.5 | 7.0 | 14.0 | 28.0 |
Note: Actual factory output is based on the inspection certificate. Grade 000 is an ultra-precision reference and is rarely used for routine measurements.
II. Grade Definitions and Application Scenarios (Directly Determine Measurement Accuracy)<\/p>\n\n\n\n

    \n
  1. 000 Grade (Ultra-Precision Reference Grade)<\/strong>
    Flatness: Sub-micron level, \u22642.4\u03bcm for a 1000mm diagonal.
    Core Uses: National metrology institutes \/ laboratory references, CMM calibration, laser interferometer references, semiconductor testing, aerospace precision calibration.
    Environmental Requirements: Constant temperature 20\u00b10.5\u2103, constant humidity, anti-vibration. Used only for highest precision traceability.<\/li>\n\n\n\n
  2. 00 Grade (Laboratory \/ Metrology Grade)<\/strong>
    Flatness: \u22644.8\u03bcm for a 1000mm diagonal.
    Core Uses: Precision metrology rooms, CMM table surfaces, optical instrument references, final inspection of precision parts, gauge block \/ tool calibration.
    Environmental Requirements: Constant temperature 20\u00b11\u2103, anti-vibration, avoid temperature fluctuations.<\/li>\n\n\n\n
  3. 0 Grade (Workshop Inspection Grade)<\/strong>
    Flatness: \u22649.7\u03bcm for a 1000mm diagonal.
    Core Uses: Factory quality inspection rooms, precision part testing, fixture reference, machine tool accuracy verification, general precision measurement.
    Environmental Requirements: Workshop constant temperature 20\u00b12\u2103, basic anti-vibration, suitable for most industrial precision scenarios.<\/li>\n\n\n\n
  4. 1 Grade (General Workshop Grade)<\/strong>
    Flatness: \u226419.4\u03bcm for a 1000mm diagonal.
    Core Uses: General mechanical machining, assembly references, general part testing, scribing, fixture positioning.
    Environmental Requirements: Conventional workshop environment, meeting medium precision measurement needs.
    III. Core Advantages of Granite Flat Plates for Precision Measurement
    Material Stability<\/strong>: Natural granite, after billions of years of natural\u65f6\u6548, has no internal stress, does not rust, is non-magnetic, and has an extremely low thermal expansion coefficient (about 2.3\u00d710\u207b\u2076\/\u2103). Temperature changes have a much smaller impact on flatness than cast iron.
    Hardness and Wear Resistance<\/strong>: Mohs hardness 6\u20137, Shore hardness \u226570HS. Resistant to wear and scratching, with long-term precision retention far exceeding metal platforms.
    Retenci\u00f3n de precisi\u00f3n<\/strong>: No plastic deformation. With proper maintenance, 00\/0 grades can be stably used for 5\u201310 years without major overhaul.
    IV. Selection and Usage Guidelines (Ensure Measurement Accuracy)<\/li>\n\n\n\n
  5. Grade Selection Principles<\/strong>
    Measurement error requirement \u22641\u03bcm: Select 000 grade
    Measurement error requirement \u22645\u03bcm: Select 00 grade
    Measurement error requirement \u226410\u03bcm: Select 0 grade
    Measurement error requirement \u226420\u03bcm: Select 1 grade
    Principle: Flat plate precision should be 3\u20135 times that of the measured workpiece to avoid reference errors dominating the measurement results.<\/li>\n\n\n\n
  6. Usage Environment Control (Critical)<\/strong>
    Temperature: 20\u00b12\u2103. Avoid direct sunlight, air conditioning blasts, and heat from dense personnel.
    Anti-vibration: Install dedicated vibration isolation supports, away from machine tools, presses, and other vibration sources.
    Cleaning: Wipe with a dust-free cloth and alcohol. Strictly prohibit hard objects from scratching. Cover with a dust cover when not in use.
    Supporting: Install strictly according to three main supports + auxiliary supports to avoid local deformation from uneven loading.<\/li>\n\n\n\n
  7. Regular Calibration<\/strong>
    000\/00 grades: Calibrate every 6 months
    0 grado: Calibrar anualmente
    1 grado: Calibrar cada 1-2 a\u00f1os
    Base de calibraci\u00f3n: JJG 117-2013 \u2018Placas planas\u2019, con certificados expedidos por instituciones de metrolog\u00eda legal.
    V. Errores comunes
    \u274c Centrarse s\u00f3lo en el grado, no en el tama\u00f1o: Para un mismo grado, mayor tama\u00f1o significa mayor tolerancia. Un grado 00 de 1000 mm no equivale a un grado 00 de 300 mm.
    \u274c Ignorar el entorno: El uso de un grado 00 en un taller general degradar\u00e1 r\u00e1pidamente su precisi\u00f3n por debajo del grado 1.
    \u274c Exceso de precisi\u00f3n: Utilizar un grado 00 cuando basta con un grado 1 conlleva un coste elevado, un mantenimiento dif\u00edcil y una mala relaci\u00f3n coste-eficacia.<\/li>\n<\/ol>\n\n\n\n
    \"\"<\/figure>","protected":false},"excerpt":{"rendered":"

    El grado de precisi\u00f3n de las placas planas de granito es la principal garant\u00eda de la exactitud de las medidas precisas. La clasificaci\u00f3n de grados se centra en la tolerancia de planitud, siguiendo las normas nacionales GB\/T 20428-2006 y JJG 117-2013. Los grados principales son 000, 00, 0 y 1. El grado 000 se utiliza para escenarios de mayor precisi\u00f3n, los grados 00\/0 para...<\/p>","protected":false},"author":1,"featured_media":1986,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_seopress_robots_primary_cat":"none","_seopress_titles_title":"","_seopress_titles_desc":"","_seopress_robots_index":"","_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-1983","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\/03\/\u5fae\u4fe1\u56fe\u7247_20260303093111_2_11-1024x527.jpg",1024,527,true],"author_info":{"display_name":"jinxing6611@gmail.com","author_link":"https:\/\/jtlcnc.com\/es\/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":119,"filter":"raw","cat_ID":35,"category_count":119,"category_description":"","cat_name":"NEWS","category_nicename":"news","category_parent":0}],"tag_info":false,"_links":{"self":[{"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/posts\/1983","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/comments?post=1983"}],"version-history":[{"count":1,"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/posts\/1983\/revisions"}],"predecessor-version":[{"id":1987,"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/posts\/1983\/revisions\/1987"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/media\/1986"}],"wp:attachment":[{"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/media?parent=1983"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/categories?post=1983"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jtlcnc.com\/es\/wp-json\/wp\/v2\/tags?post=1983"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}