{"id":2786,"date":"2026-07-23T16:42:37","date_gmt":"2026-07-23T13:12:37","guid":{"rendered":"https:\/\/kimiyachem.com\/%d8%b1%d8%a7%d9%87%d9%86%d9%85%d8%a7%db%8c-%d8%ac%d8%a7%d9%85%d8%b9-%d8%a7%d9%86%d8%af%d8%a7%d8%b2%d9%87%da%af%db%8c%d8%b1%db%8c-%d8%ba%d9%84%d8%b8%d8%aa-%d8%a2%d8%a8%d8%b5%d8%a7-2\/"},"modified":"2026-10-15T11:02:30","modified_gmt":"2026-10-15T07:32:30","slug":"measure-metalworking-fluid-concentration-refractometer","status":"publish","type":"post","link":"https:\/\/kimiyachem.com\/en\/measure-metalworking-fluid-concentration-refractometer\/","title":{"rendered":"How to Measure Metalworking Fluid Concentration with a Refractometer"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\"><strong>Category:<\/strong> Technical and practical guide | <strong>Author:<\/strong> Kimiya Sanat Savalan Research and Development (R&amp;D) Unit<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Estimating metalworking-fluid concentration by eye is a costly mistake in machining shops, CNC operations and rolling lines. Too little or too much concentrate can lead to poor tool performance, corrosion, damaged cutting inserts and unnecessary fluid consumption.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The most efficient and fastest tool for measuring the concentration of water-miscible metalworking fluid in the workshop <strong>Optical refractometer device (Refractometer)<\/strong> is But what is the correct way to use this tool and why is the percentage read on the device usually different from the actual concentration of the emulsion?<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">1. Why is coolant concentration control so important?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The performance of the metalworking fluid is completely dependent on its mixing percentage with water. Deviation from the standard concentration creates two dangerous scenarios:<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">a) Consequences of very low concentration (less than 3%:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Fast rusting and corrosion:<\/strong> Reducing the dose of corrosion and rust inhibitors on the part and rail of the machine.<\/li>\n\n\n\n<li><strong>Reduced tool life:<\/strong> Severe wear of the chipping tool due to insufficient supply of lubricating film.<\/li>\n\n\n\n<li><strong>Rapid growth of bacteria:<\/strong> Weakening of the concentration of biocides and premature spoilage of the liquid.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">b) Consequences of very high concentration (above 8% to 10%:<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Huge financial loss:<\/strong> Excessive and unnecessary consumption of oil.<\/li>\n\n\n\n<li><strong>Reduction of cooling properties:<\/strong> Due to the high concentration of oil and the lowering of the heat capacity of the liquid.<\/li>\n\n\n\n<li><strong>Creating annoying foam and adhesion:<\/strong> Remaining adhesive layers on the piece and making the tool hot.<\/li>\n\n\n\n<li><strong>Skin Irritation:<\/strong> Cause dermatitis and skin allergies for the device operator.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">2. How does a refractometer work?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A manual refractometer is an instrument based on <strong>Law of refraction of light (Refraction)<\/strong> works by measuring changes in light refraction through the fluid. The refractive index varies with the fluid&#8217;s composition and concentration. The instrument displays a reading, usually in <strong>Brix<\/strong>) is displayed.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">3. Understanding the refractometer correction factor<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The biggest workshop error is that the number read on the refractometer eyepiece (eg <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>4<\/mn><\/mrow><annotation encoding=\"application\/x-tex\">4<\/annotation><\/semantics><\/math>4) is assumed directly as &#8220;concentration percentage of 4%&#8221;!<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Technical Insight:<\/strong> degree <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mi>B<\/mi><mi>r<\/mi><mi>i<\/mi><mi>x<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">Brix<\/annotation><\/semantics><\/math>A Brix reading reflects the fluid&#8217;s refractive index; it is not a direct measurement of the oil percentage. Mineral, semi-synthetic, synthetic and vegetable-oil formulations each require their own <strong>Correction factor (Multiplying Factor)<\/strong> they say.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Calculation formula of actual concentration:<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\" display=\"block\"><semantics><mrow><mtext>Actual concentration (%)<\/mtext><mo>=<\/mo><mtext>Refractometer reading (Brix)<\/mtext><mo>\u00d7<\/mo><mtext>Fluid Correction Factor (factor<\/mtext><\/mrow><annotation encoding=\"application\/x-tex\">\\text{Actual concentration percentage (\\%)} = \\text{The number read on the refractometer (Brix)} \\times \\text{Oil correction factor (Factor))}<\/annotation><\/semantics><\/math>Actual concentration (%) = Refractometer reading (Brix) \u00d7 Fluid correction factor<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Practical example:<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Suppose from the product <strong><code>SVL FLUID E100<\/code><\/strong> You use a correction factor equal to <strong>1.01.01.0<\/strong> is If refractometer no <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>4<\/mn><\/mrow><annotation encoding=\"application\/x-tex\">4<\/annotation><\/semantics><\/math>Show 4, your concentration exactly <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>4<\/mn><mi mathvariant=\"normal\">%<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">4\\%<\/annotation><\/semantics><\/math>It is 4% (<math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>4<\/mn><mo>\u00d7<\/mo><mn>1.0<\/mn><mo>=<\/mo><mn>4<\/mn><mi mathvariant=\"normal\">%<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">4 \\times 1.0 = 4\\%<\/annotation><\/semantics><\/math>4\u00d71.0=4%).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But if from a semi-synthetic product or special base with a correction factor <strong>1.51.51.5<\/strong> Use and refractometer number <math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>4<\/mn><\/mrow><annotation encoding=\"application\/x-tex\">4<\/annotation><\/semantics><\/math>4 show, your actual concentration is equal <strong>6%6\\%6%<\/strong> will be (<math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>4<\/mn><mo>\u00d7<\/mo><mn>1.5<\/mn><mo>=<\/mo><mn>6<\/mn><mi mathvariant=\"normal\">%<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">4 \\times 1.5 = 6\\%<\/annotation><\/semantics><\/math>4&#215;1.5=6%)! Ignoring this coefficient will make you misdiagnose the concentration of the liquid.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">4. Step-by-step instructions for calibration and measurement in the workshop<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Follow the steps below daily or weekly to get an accurate number:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Clean the Prism:<\/strong> Wipe the glass prism and the clear cover of the refractometer with a soft, lint-free cloth.<\/li>\n\n\n\n<li><strong>Calibration with distilled water (zero point):<\/strong> Put 1-2 drops of distilled water or pure water on the prism, close the cap and look in front of the light. The blue\/white dividing line should be exactly on the number <strong>000<\/strong> be Otherwise, turn the adjustment screw on the top of the device to calibrate to zero.<\/li>\n\n\n\n<li><strong>Correct sampling:<\/strong> Take the sample directly from the spray nozzle (in operation), not from the stagnant surface of the tank where suspended oils float.<\/li>\n\n\n\n<li><strong>Read the Scale:<\/strong> Pour 1 or 2 drops of the emulsion on the prism and read the border line number.<\/li>\n\n\n\n<li><strong>Apply the Refractometer Factor:<\/strong> Multiply the number read by the factor listed on the TDS sheet of the product.<\/li>\n<\/ol>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">5. Suggested concentration table for all types of machining operations<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><em>content_copy<\/em><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th class=\"has-text-align-left\" data-align=\"left\">Type of operation<\/th><th class=\"has-text-align-left\" data-align=\"left\">Suggested actual concentration range (%)<\/th><th class=\"has-text-align-left\" data-align=\"left\">Technical considerations<\/th><\/tr><\/thead><tbody><tr><td class=\"has-text-align-left\" data-align=\"left\"><strong>Grinding and Light Machining<\/strong><\/td><td class=\"has-text-align-left\" data-align=\"left\"><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>2.5<\/mn><mi mathvariant=\"normal\">%<\/mi><mo>\u2212<\/mo><mn>4.0<\/mn><mi mathvariant=\"normal\">%<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">2.5\\% &#8211; 4.0\\%<\/annotation><\/semantics><\/math>2.5%\u22124.0%<\/td><td class=\"has-text-align-left\" data-align=\"left\">The need for maximum cooling and chip washing<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\"><strong>General Turning and Milling<\/strong><\/td><td class=\"has-text-align-left\" data-align=\"left\"><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>4.0<\/mn><mi mathvariant=\"normal\">%<\/mi><mo>\u2212<\/mo><mn>6.0<\/mn><mi mathvariant=\"normal\">%<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">4.0\\% &#8211; 6.0\\%<\/annotation><\/semantics><\/math>4.0%\u22126.0%<\/td><td class=\"has-text-align-left\" data-align=\"left\">Balance between lubrication and cooling<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\"><strong>Tapping, Deep-Hole Drilling and Heavy Machining<\/strong><\/td><td class=\"has-text-align-left\" data-align=\"left\"><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>6.0<\/mn><mi mathvariant=\"normal\">%<\/mi><mo>\u2212<\/mo><mn>9.0<\/mn><mi mathvariant=\"normal\">%<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">6.0\\% &#8211; 9.0\\%<\/annotation><\/semantics><\/math>6.0%\u22129.0%<\/td><td class=\"has-text-align-left\" data-align=\"left\">The need for strength of the lubricating film and high pressure resistance<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\"><strong>Cold Rolling of Tubes and Profiles<\/strong><\/td><td class=\"has-text-align-left\" data-align=\"left\"><math xmlns=\"http:\/\/www.w3.org\/1998\/Math\/MathML\"><semantics><mrow><mn>3.0<\/mn><mi mathvariant=\"normal\">%<\/mi><mo>\u2212<\/mo><mn>5.0<\/mn><mi mathvariant=\"normal\">%<\/mi><\/mrow><annotation encoding=\"application\/x-tex\">3.0\\% &#8211; 5.0\\%<\/annotation><\/semantics><\/math>3.0%\u22125.0%<\/td><td class=\"has-text-align-left\" data-align=\"left\">Stability in high flow circulation and stain control<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">conclusion<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Refractometer is a simple but very powerful tool for quality control of metalworking fluid. By allocating only 3 minutes a day to monitor the concentration and multiply the number <strong>Standard correction coefficient of Savalan lubricants<\/strong>, You can dramatically increase the life of your emulsion and tools and reduce production line operating costs.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Technical support team <strong>Kimiya Sanat Savalan<\/strong>, Provides accurate correction factor for all SVL series grades in Technical Data Sheets (TDS) and is ready to calibrate and train measuring instruments at your factory site.<\/p>\n<div style=\"margin: 20px 0;\"><div class=\"qrcswholewtapper\" style=\"text-align:left;\"><div class=\"qrcprowrapper\"  id=\"qrcwraa2leds\"><div class=\"qrc_canvass\" id=\"qrc_cuttenpages_2\" style=\"display:inline-block\" data-text=\"https:\/\/kimiyachem.com\/en\/measure-metalworking-fluid-concentration-refractometer\/\"><\/div><div><a download=\"How to Measure Metalworking Fluid Concentration with a Refractometer.png\" class=\"qrcdownloads\" id=\"worign\">\r\n           <button type=\"button\" style=\"min-width:200px;background:#dddddd;color:#000;font-weight: 600;border: 1px solid #dddddd;border-radius:4px;font-size:12px;padding: 6px 0;\" class=\"uqr_code_btn\">Download QR<\/button>\r\n           <\/a><\/div><\/div><\/div><\/div>","protected":false},"excerpt":{"rendered":"<p>Category: Technical and practical guide | Author: Kimiya Sanat Savalan Research and Development (R&amp;D) Unit Estimating metalworking-fluid concentration by eye &#8230; <a class=\"cz_readmore\" href=\"https:\/\/kimiyachem.com\/en\/measure-metalworking-fluid-concentration-refractometer\/\"><i class=\"fas fa-angle-left\" aria-hidden=\"true\"><\/i><span>\u0627\u0637\u0644\u0627\u0639\u0627\u062a \u0628\u06cc\u0634\u062a\u0631<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":1926,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[124],"tags":[],"class_list":["post-2786","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/posts\/2786","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/comments?post=2786"}],"version-history":[{"count":4,"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/posts\/2786\/revisions"}],"predecessor-version":[{"id":3130,"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/posts\/2786\/revisions\/3130"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/media\/1926"}],"wp:attachment":[{"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/media?parent=2786"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/categories?post=2786"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kimiyachem.com\/en\/wp-json\/wp\/v2\/tags?post=2786"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}