{"id":510,"date":"2026-03-23T08:21:02","date_gmt":"2026-03-23T08:21:02","guid":{"rendered":"https:\/\/kurtfoundry.com\/?p=510"},"modified":"2026-04-02T05:16:42","modified_gmt":"2026-04-02T05:16:42","slug":"custom-flywheels","status":"publish","type":"post","link":"https:\/\/kurtfoundry.com\/fr\/product\/custom-flywheels\/","title":{"rendered":"Volants d'inertie sur mesure | Fonderie de moulage au sable"},"content":{"rendered":"\n<style>\n    @import url('https:\/\/fonts.googleapis.com\/css2?family=Playfair+Display:wght@400;500;600;700&family=Open+Sans:wght@300;400;600&display=swap');\n\n    :root {\n        --primary-dark: #0a0e0d;\n        --primary: #2b3a36;\n        --primary-light: #445851;\n        --accent: #d4af37;\n        --bg-light: #f9f8f4;\n        --bg-white: #ffffff;\n        --bg-gray: #f0efe9;\n        --text-main: #333333;\n        --text-muted: #666666;\n        --text-light: #e0e0e0;\n        --border: #e2dfd5;\n        --transition: all 0.4s cubic-bezier(0.25, 1, 0.5, 1);\n        --text: #333333; 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}\n        .fw-hero h1 { font-size: 3.8rem; }\n        .fw-intro-grid { grid-template-columns: 1fr 1fr; align-items: center; }\n        .fw-features-grid { grid-template-columns: 1fr 1fr; }\n        \/* Update grid to 2 columns for tablet\/desktop *\/\n        .fw-checklist { grid-template-columns: 1fr 1fr; }\n        .fw-timeline { padding-left: 0; border-left: none; }\n        .fw-timeline::before {\n            content: ''; position: absolute; left: 50%; top: 0; bottom: 0;\n            width: 2px; background: rgba(212, 175, 55, 0.3); transform: translateX(-50%);\n        }\n        .fw-step { width: 50%; padding-left: 0; padding-right: 3rem; text-align: right; margin-bottom: 4rem; }\n        .fw-step:nth-child(even) { margin-left: auto; padding-right: 0; padding-left: 3rem; text-align: left; }\n        .fw-step::before { left: auto; right: -10px; }\n        .fw-step:nth-child(even)::before { left: -10px; right: auto; }\n    }\n    @media (min-width: 1024px) {\n        .fw-hero h1 { font-size: 4.2rem; }\n    }\n<\/style>\n\n<div class=\"fw-page\">\n\n    <section class=\"fw-hero\">\n        <img decoding=\"async\" src=\"https:\/\/kurtfoundry.com\/wp-content\/uploads\/2026\/03\/custom-flywheels-1-1.webp\" alt=\"Wide-angle photograph of a massive, freshly CNC-machined custom gray iron flywheel resting on a heavy-duty wooden shipping pallet inside a bright, modern foundry. The flywheel features a perfectly smooth turned outer diameter and a precision-bored center hole with a cut keyway. Overhead LED factory lighting reflects off the machined steel surfaces.\" class=\"fw-hero-bg\" title=\"\">\n        <div class=\"fw-hero-overlay\"><\/div>\n        <div class=\"fw-container fw-hero-content reveal-up\">\n            <span class=\"fw-hero-subtitle\">Direct-Factory Custom Sand Casting<\/span>\n            <h1>Custom Flywheels<br>Engineered for Precision &#038; Balance<\/h1>\n            <p>We engineer and manufacture heavy-duty custom cast iron flywheels for industrial machinery, diesel engines, and stamping presses. Kurt Foundry delivers fully CNC-machined, porosity-free flywheels directly to your North American facility.<\/p>\n            <div class=\"fw-hero-badges\">\n                <span class=\"fw-hero-badge\">ISO 9001 Certified<\/span>\n                <span class=\"fw-hero-badge\">ASTM Compliant<\/span>\n                <span class=\"fw-hero-badge\">15,000+ Tons Output<\/span>\n            <\/div>\n            <div class=\"fw-hero-actions\">\n                <a href=\"\/contact\/\" class=\"btn btn-accent\">Get a Free Quote<\/a>\n                <a href=\"#specs\" class=\"btn btn-outline\">View Material Specs<\/a>\n            <\/div>\n        <\/div>\n    <\/section>\n\n    <section class=\"fw-section fw-intro\">\n        <div class=\"fw-container\">\n            <div class=\"fw-intro-grid\">\n                <div class=\"fw-intro-text reveal-up\">\n                    <h2>The Foundation of Rotational Stability<\/h2>\n                    <p>Industrial flywheels require immense structural integrity and perfect mass distribution to store rotational energy safely. A minor internal casting defect can cause catastrophic failure at high rotational speeds. Kurt Foundry custom-engineers heavy-duty flywheels to meet your exact dimensional and metallurgical specifications.<\/p>\n                    <p>We utilize furan resin sand casting to pour medium to massive flywheels weighing up to 5,000 lbs. By combining advanced 3D solidification simulation with in-house 5-axis CNC machining, we guarantee perfect concentricity and strict dynamic balancing tolerances. Our engineering team reviews every CAD file to ensure the hub and web transition areas solidify without internal shrinkage.<\/p>\n                <\/div>\n                <div class=\"fw-intro-highlight reveal-scale delay-1\">\n                    <p>Whether you need high-damping <a href=\"\/capabilities\/custom-gray-iron-castings\/\">custom gray iron castings<\/a> for heavy stamping presses or high-strength <a href=\"\/capabilities\/custom-ductile-iron-castings\/\">custom ductile iron castings<\/a> for high-RPM diesel engines, we deliver Ready-To-Assemble components directly to your loading dock. Procurement managers and lead engineers eliminate the middleman and deal directly with the foundry experts.<\/p>\n                <\/div>\n            <\/div>\n        <\/div>\n    <\/section>\n\n    <section id=\"specs\" class=\"fw-section fw-specs\">\n        <div class=\"fw-container\">\n            <div class=\"fw-specs-header reveal-up\">\n                <h2>Flywheel Material Grades &#038; Specifications<\/h2>\n            <\/div>\n            <div class=\"fw-table-card reveal-up delay-1\">\n                <div class=\"fw-table-wrapper\">\n                    <table class=\"fw-table\">\n                        <thead>\n                            <tr>\n                                <th>Standard \/ Grade<\/th>\n                                <th>Tensile Strength (MPa)<\/th>\n                                <th>Yield Strength (MPa)<\/th>\n                                <th>Elongation (%)<\/th>\n                                <th>Common Applications<\/th>\n                            <\/tr>\n                        <\/thead>\n                        <tbody>\n                            <tr>\n                                <td>ASTM A48 Class 30 (Gray Iron)<\/td>\n                                <td>&ge; 207<\/td>\n                                <td>N\/A (Brittle)<\/td>\n                                <td>N\/A<\/td>\n                                <td>Standard industrial press flywheels, machine tools, vibration dampers.<\/td>\n                            <\/tr>\n                            <tr>\n                                <td>ASTM A48 Class 40 (Gray Iron)<\/td>\n                                <td>&ge; 276<\/td>\n                                <td>N\/A (Brittle)<\/td>\n                                <td>N\/A<\/td>\n                                <td>Heavy-duty crushers, large compressor flywheels requiring higher strength.<\/td>\n                            <\/tr>\n                            <tr>\n                                <td>ASTM A536 65-45-12 (Ductile Iron)<\/td>\n                                <td>&ge; 448<\/td>\n                                <td>&ge; 310<\/td>\n                                <td>&ge; 12<\/td>\n                                <td>High-RPM engine flywheels, high-stress rotational applications.<\/td>\n                            <\/tr>\n                            <tr>\n                                <td>ASTM A536 80-55-06 (Ductile Iron)<\/td>\n                                <td>&ge; 552<\/td>\n                                <td>&ge; 379<\/td>\n                                <td>&ge; 6<\/td>\n                                <td>Severe-duty industrial equipment requiring maximum burst resistance.<\/td>\n                            <\/tr>\n                        <\/tbody>\n                    <\/table>\n                <\/div>\n            <\/div>\n        <\/div>\n    <\/section>\n\n    <section class=\"fw-section fw-features\">\n        <div class=\"fw-container\">\n            <div class=\"fw-features-grid\">\n                <div class=\"fw-features-content reveal-up\">\n                    <h2>Precision Machining &#038; Perfect Concentricity<\/h2>\n                    <p>A raw casting is useless if the final part wobbles on the drive shaft. We perform all CNC turning, boring, and keyway broaching in-house. This single-source manufacturing approach ensures the final custom flywheel meets strict runout tolerances.<\/p>\n                    <p>By controlling both the casting process and the final machining, we deliver a perfectly concentric component that requires minimal dynamic balancing before final assembly.<\/p>\n                <\/div>\n                <div class=\"fw-features-image-wrap reveal-scale delay-1\">\n                    <img decoding=\"async\" src=\"https:\/\/kurtfoundry.com\/wp-content\/uploads\/2026\/03\/custom-flywheels-2-1.webp\" alt=\"Close-up macro photograph of a 5-axis CNC milling machine cutting the central bore of a heavy custom sand-cast ductile iron flywheel. Sharp metal shavings are flying off the cutting tool, and bright white liquid coolant is spraying onto the dark gray iron surface. The background is a blurred industrial factory setting.\" class=\"product-img\" loading=\"lazy\" width=\"900\" height=\"600\" title=\"\">\n                <\/div>\n            <\/div>\n        <\/div>\n    <\/section>\n\n    <section class=\"fw-section fw-process\">\n        <div class=\"fw-container\">\n            <div class=\"fw-process-header reveal-up\">\n                <h2>Our Custom Flywheel Manufacturing Process<\/h2>\n            <\/div>\n            <div class=\"fw-timeline\">\n                <div class=\"fw-step reveal-up\">\n                    <h3>1. DFM Review &#038; Casting Simulation<\/h3>\n                    <p>We analyze your flywheel CAD model using Magmasoft 3D simulation. We engineer optimized gating and riser systems to feed molten metal directly into the heavy central hub, preventing internal shrinkage porosity.<\/p>\n                <\/div>\n                <div class=\"fw-step reveal-up delay-1\">\n                    <h3>2. Resin Sand Molding<\/h3>\n                    <p>Our automated molding lines utilize furan resin sand to create exceptionally rigid molds. Understanding the different <a href=\"\/blog\/types-sand-used-sand-casting\/\" style=\"color: var(--accent);\">types of sand used in sand casting<\/a> allows us to prevent mold wall movement, ensuring the heavy flywheel maintains exact dimensional accuracy during pouring.<\/p>\n                <\/div>\n                <div class=\"fw-step reveal-up\">\n                    <h3>3. Spectrometer-Verified Pouring<\/h3>\n                    <p>Before pouring the molten iron, we conduct rigorous spectrometric analysis. We verify the exact Carbon Equivalent (CE) for gray iron or the nodularity rate for ductile iron to guarantee the flywheel meets your specified ASTM standard.<\/p>\n                <\/div>\n                <div class=\"fw-step reveal-up delay-1\">\n                    <h3>4. Thermal Stress Relief<\/h3>\n                    <p>Heavy flywheels feature thick hubs and thin outer webs, which cool at different rates. We perform controlled thermal stress relief heat treatment to eliminate internal residual stresses, preventing the flywheel from warping during the machining phase.<\/p>\n                <\/div>\n                <div class=\"fw-step reveal-up\">\n                    <h3>5. CNC Machining &#038; Inspection<\/h3>\n                    <p>We shot-blast the raw casting and transfer it to our 5-axis CNC machining centers. Our machinists turn the outer diameter, precision-bore the center hole, and cut the keyways. Finally, we verify all critical dimensions using Coordinate Measuring Machine (CMM) inspection.<\/p>\n                <\/div>\n            <\/div>\n        <\/div>\n    <\/section>\n\n    <section class=\"fw-section fw-quality\">\n        <div class=\"fw-container\">\n            <div class=\"fw-quality-header reveal-up\">\n                <h2>Uncompromising Quality Control<\/h2>\n                <p>Flywheels are safety-critical components. We do not guess on quality; we verify every specification before the part leaves our facility. Our in-house laboratory provides the testing and documentation that North American lead engineers demand.<\/p>\n            <\/div>\n            <ul class=\"fw-checklist reveal-up delay-1\">\n                <li>\n                    <strong>Ultrasonic Testing (UT):<\/strong>\n                    <span>We scan the heavy hub sections to guarantee zero internal voids or shrinkage cavities that could compromise burst strength.<\/span>\n                <\/li>\n                <li>\n                    <strong>Spectrometry &#038; MTRs:<\/strong>\n                    <span>We provide fully traceable Material Test Reports proving the exact chemical composition of your specific casting batch.<\/span>\n                <\/li>\n                <li>\n                    <strong>CMM Dimensional Verification:<\/strong>\n                    <span>We measure the machined bore and outer diameter to ensure perfect concentricity and tight runout tolerances.<\/span>\n                <\/li>\n                <li>\n                    <strong>Magnetic Particle Inspection (MPI):<\/strong>\n                    <span>We check high-stress transition areas for microscopic surface cracks before final packaging.<\/span>\n                <\/li>\n            <\/ul>\n        <\/div>\n    <\/section>\n\n    <section class=\"fw-section fw-faq\">\n        <div class=\"fw-container\">\n            <div class=\"fw-faq-header reveal-up\">\n                <h2>Frequently Asked Questions<\/h2>\n            <\/div>\n            <div class=\"fw-faq-list reveal-up delay-1\">\n                <div class=\"fw-faq-item\">\n                    <button class=\"fw-faq-btn faq-question\" aria-expanded=\"false\" aria-controls=\"faq1\">\n                        <span>What is the best material for a custom industrial flywheel?<\/span>\n                        <span class=\"fw-faq-icon\">+<\/span>\n                    <\/button>\n                    <div id=\"faq1\" class=\"fw-faq-content\">\n                        <p>The ideal material depends on your operating speeds and stress requirements. Gray iron (ASTM A48) is the most common choice because it offers excellent vibration damping and is highly cost-effective. However, if the flywheel operates at extremely high RPMs or faces severe impact loads, ductile iron (ASTM A536) provides the necessary tensile strength and ductility to prevent bursting.<\/p>\n                    <\/div>\n                <\/div>\n                <div class=\"fw-faq-item\">\n                    <button class=\"fw-faq-btn faq-question\" aria-expanded=\"false\" aria-controls=\"faq2\">\n                        <span>How do you prevent internal porosity in the heavy flywheel hub?<\/span>\n                        <span class=\"fw-faq-icon\">+<\/span>\n                    <\/button>\n                    <div id=\"faq2\" class=\"fw-faq-content\">\n                        <p>The massive central hub of a flywheel cools slower than the outer web, making it highly susceptible to internal shrinkage cavities. We solve this problem by running advanced Magmasoft solidification simulations before cutting any tooling. To understand our approach to feeding molten metal, read more about <a href=\"\/blog\/sand-casting-how-it-works\/\">how sand casting works<\/a> and how we engineer our risers.<\/p>\n                    <\/div>\n                <\/div>\n                <div class=\"fw-faq-item\">\n                    <button class=\"fw-faq-btn faq-question\" aria-expanded=\"false\" aria-controls=\"faq3\">\n                        <span>What size custom flywheels can Kurt Foundry manufacture?<\/span>\n                        <span class=\"fw-faq-icon\">+<\/span>\n                    <\/button>\n                    <div id=\"faq3\" class=\"fw-faq-content\">\n                        <p>Our heavy resin sand casting lines and floor molding pits allow us to pour custom flywheels ranging from 50 lbs up to 5,000 lbs (2.5 tons) per single piece.<\/p>\n                    <\/div>\n                <\/div>\n                <div class=\"fw-faq-item\">\n                    <button class=\"fw-faq-btn faq-question\" aria-expanded=\"false\" aria-controls=\"faq4\">\n                        <span>Do you dynamically balance the flywheels before shipping?<\/span>\n                        <span class=\"fw-faq-icon\">+<\/span>\n                    <\/button>\n                    <div id=\"faq4\" class=\"fw-faq-content\">\n                        <p>We supply fully CNC-machined flywheels with incredibly tight concentricity and runout tolerances. This precision machining ensures the flywheel is statically balanced and very close to perfect dynamic balance. Most of our OEM customers perform the final fine-tune dynamic balancing after mounting the flywheel to their specific motor assembly.<\/p>\n                    <\/div>\n                <\/div>\n                <div class=\"fw-faq-item\">\n                    <button class=\"fw-faq-btn faq-question\" aria-expanded=\"false\" aria-controls=\"faq5\">\n                        <span>Can you ship heavy cast iron flywheels to the USA and Canada?<\/span>\n                        <span class=\"fw-faq-icon\">+<\/span>\n                    <\/button>\n                    <div id=\"faq5\" class=\"fw-faq-content\">\n                        <p>Yes. We export over 80% of our castings to North America. We package all heavy flywheels in ISPM-15 certified fumigated wooden crates with rust-preventative coatings. We offer Delivered Duty Paid (DDP) shipping, meaning we handle the ocean freight, customs clearance, and trucking directly to your facility.<\/p>\n                    <\/div>\n                <\/div>\n            <\/div>\n        <\/div>\n    <\/section>\n\n    <section class=\"fw-section fw-cta\">\n        <div class=\"fw-container reveal-scale\">\n            <div class=\"fw-cta-content\">\n                <h2>Ready to Quote Your Custom Flywheel Project?<\/h2>\n                <p>Send us your 2D drawings and 3D CAD files today. Our foundry engineering team will provide a comprehensive Design for Manufacturability (DFM) review and a competitive direct-factory quote within 48 hours.<\/p>\n                <a href=\"\/contact\/\" class=\"btn btn-accent\">Get Your Free Quote Now<\/a>\n            <\/div>\n        <\/div>\n    <\/section>\n\n<\/div>\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\": \"https:\/\/schema.org\/\",\n  \"@type\": \"Product\",\n  \"name\": \"Custom Cast Iron Flywheels\",\n  \"image\": \"https:\/\/kurtfoundry.com\/wp-content\/uploads\/2026\/03\/custom-flywheels-1-1.webp\",\n  \"description\": \"Heavy-duty custom cast iron flywheels engineered for industrial machinery, diesel engines, and stamping presses. 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