{"id":20518,"date":"2026-04-29T11:08:22","date_gmt":"2026-04-29T14:08:22","guid":{"rendered":"https:\/\/chousa.com.ar\/?p=20518"},"modified":"2026-07-23T13:54:06","modified_gmt":"2026-07-23T16:54:06","slug":"bulones-12-9-sembradoras-fallas","status":"publish","type":"post","link":"https:\/\/chousa.com.ar\/en\/bulones-12-9-sembradoras-fallas\/","title":{"rendered":"The problem with 12.9 bolts in seed drills"},"content":{"rendered":"<h3>The Problem with 12.9 Bolts in Seeders<\/h3>\n<p>In seeders, 12.9 bolts operate under particularly demanding conditions: constant vibration generated by the ground, repetitive dynamic loads, and continuous exposure to moisture, fertilizers, and accumulated dirt.<\/p>\n<p>These conditions subject 12.9 bolts in seeders to a higher level of stress than in other industrial applications.<\/p>\n<p>In practice, the bolts usually meet the mechanical specification. However, failures such as the following occur in service:<\/p>\n<ul>\n<li><strong>Loosening<\/strong><\/li>\n<li><strong>Premature corrosion<\/strong><\/li>\n<li><strong>Unexpected breakage<\/strong><\/li>\n<\/ul>\n<p>This explains why 12.9 bolts fail in the field: the problem lies not only in the material, but also in the behavior of the entire system.<\/p>\n<hr \/>\n<h3>Where are 12.9 bolts used on a seed drill?<\/h3>\n<p>They are used in joints subjected to high loads and vibration, where stability is critical.<\/p>\n<p>Primarily in:<\/p>\n<ul>\n<li><strong>Seeder wheel bolts<\/strong><\/li>\n<li><strong>Seeder unit fastenings<\/strong><\/li>\n<li><strong>Structural connections<\/strong><\/li>\n<\/ul>\n<p>In these applications, the combination of mechanical load, vibration, and harsh environments demands a reliable fastening system.<\/p>\n<hr \/>\n<h2>3 Types of Failures in 12.9 Bolts in the Field<\/h2>\n<h3>1. Loosening Due to Vibration in Seeders<\/h3>\n<p>Loosening due to vibration is one of the main causes of failure in 12.9 bolts.<\/p>\n<p>During field work:<\/p>\n<ul>\n<li><strong>Vibrations generate micro-movements<\/strong><\/li>\n<li><strong>The bolt preload is lost.<\/strong><\/li>\n<li><strong>The joint begins to move.<\/strong><\/li>\n<\/ul>\n<p>This process directly impacts the reliability of fasteners such as <strong>seeder wheel bolts<\/strong>where the loss of preload can lead to progressive failure.<\/p>\n<hr \/>\n<h3>2. Corrosion<\/h3>\n<p>Corrosion in seeders is another critical factor.<\/p>\n<p>The fasteners are exposed to:<\/p>\n<ul>\n<li><strong>Fertilizers<\/strong><\/li>\n<li><strong>Humidity<\/strong><\/li>\n<li><strong>Accumulated dirt<\/strong><\/li>\n<\/ul>\n<p>This generates phenomena such as:<\/p>\n<ul>\n<li><strong>Localized corrosion<\/strong><\/li>\n<li><strong>Under-deposit corrosion<\/strong><\/li>\n<\/ul>\n<p>In addition to deteriorating the material, corrosion modifies the friction between the threads, affecting the torque and stability of the joint.<\/p>\n<hr \/>\n<h3>3. Hydrogen Embrittlement<\/h3>\n<p>Hydrogen embrittlement is a critical problem in 12.9 bolts.<\/p>\n<p>This phenomenon occurs when processes such as electroplating introduce hydrogen into the material.<\/p>\n<p>Hydrogen embrittlement can cause:<\/p>\n<ul>\n<li><strong>Internal microcracks<\/strong><\/li>\n<li><strong>Loss of ductility<\/strong><\/li>\n<li><strong>Sudden failures in service<\/strong><\/li>\n<\/ul>\n<p>This is one of the main reasons why 12.9 bolts fail without prior warning.<\/p>\n<hr \/>\n<h3>The most common failure in 12.9 bolts<\/h3>\n<p>It is still used in many applications:<\/p>\n<ul>\n<li><strong>Electrolytic zinc plating<\/strong><\/li>\n<li><strong>Dichromated (yellow zinc plating)<\/strong><\/li>\n<\/ul>\n<p>This occurs due to:<\/p>\n<ul>\n<li><strong>Cost<\/strong><\/li>\n<li><strong>Historical use<\/strong><\/li>\n<\/ul>\n<p>However, in <strong>12.9 bolts in seed drills<\/strong>, these solutions present problems:<\/p>\n<ul>\n<li><strong>Risk of hydrogen embrittlement<\/strong><\/li>\n<li><strong>Low corrosion resistance<\/strong><\/li>\n<li><strong>Unstable behavior in the field<\/strong><\/li>\n<\/ul>\n<p>Therefore, yellow zinc plating is one of the main causes of failure in agricultural fasteners.<\/p>\n<hr \/>\n<h2>How to prevent failures in 12.9 bolts?<\/h2>\n<h3>Laurentcoat\u00ae + Precote\u00ae<\/h3>\n<p>The most effective way to prevent failures in 12.9 bolts is through a coating and fastening system designed for real-world conditions.<\/p>\n<p><strong>Laurentcoat\u00ae:<\/strong><\/p>\n<ul>\n<li><strong>Non-electrolytic coating \u2013&gt; prevents hydrogen embrittlement<\/strong><\/li>\n<li><strong>High corrosion resistance<\/strong><\/li>\n<li><strong>Controlled thickness \u2013&gt; does not affect threads<\/strong><\/li>\n<li><strong>Stable friction \u2013&gt; improves torque<\/strong><\/li>\n<\/ul>\n<p><strong>Precote\u00ae:<\/strong><\/p>\n<ul>\n<li><strong>Prevents loosening due to vibration<\/strong><\/li>\n<li><strong>Maintains preload<\/strong><\/li>\n<li><strong>Improves joint reliability<\/strong><\/li>\n<\/ul>\n<p>This type of solution is especially effective in critical applications such as <strong>Wheel Bolts on Seeders<\/strong>.<\/p>\n<hr \/>\n<h3>Conclusion<\/h3>\n<p>Failures in 12.9 bolts on seeders are not solely due to the material, but to a combination of loosening, corrosion, and embrittlement under real operating conditions.<\/p>\n<p>If you are experiencing problems with loosening, corrosion, or breakage in the field, we can analyze your application and propose a specific solution to improve the reliability of your fasteners.<\/p>\n<p><strong>You can contact us at <a href=\"mailto:info@chousa.com.ar\">info@chousa.com.ar<\/a> and get in touch with our technical team.<\/strong><\/p>","protected":false},"excerpt":{"rendered":"<p>In seeders, 12.9 bolts operate under particularly demanding conditions: constant vibration generated by the ground, repetitive dynamic loads, and continuous exposure to moisture, fertilizers, and accumulated dirt.<\/p>","protected":false},"author":3,"featured_media":20519,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-20518","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"acf":[],"_links":{"self":[{"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/posts\/20518","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/comments?post=20518"}],"version-history":[{"count":9,"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/posts\/20518\/revisions"}],"predecessor-version":[{"id":28149,"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/posts\/20518\/revisions\/28149"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/media\/20519"}],"wp:attachment":[{"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/media?parent=20518"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/categories?post=20518"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chousa.com.ar\/en\/wp-json\/wp\/v2\/tags?post=20518"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}