Interchangeability of bevel pairs: they’re always replaced together<\/title>\n\n <link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n <link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin=\"\">\n <link href=\"https:\/\/fonts.googleapis.com\/css2?family=Inter:wght@400;500;600;700&display=swap\" rel=\"stylesheet\">\n\n <style>\n *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }\n\n :root {\n --green: #1a6b3c;\n --green-dark: #0f4a28;\n --green-mid: #2d8a55;\n --green-light: #e8f4ed;\n --green-xlight: #f2faf5;\n --amber: #b45309;\n --amber-light: #fef3c7;\n\n --bg: #ffffff;\n --bg-soft: #f8f9fa;\n --bg-muted: #f1f3f5;\n --border: #e5e7eb;\n --border-mid: #d1d5db;\n\n --text-primary: #111827;\n --text-secondary: #4b5563;\n --text-muted: #9ca3af;\n\n --radius-sm: 6px;\n --radius-md: 8px;\n --radius-lg: 12px;\n --shadow-sm: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);\n --shadow-md: 0 4px 12px rgba(0,0,0,.08), 0 2px 4px rgba(0,0,0,.04);\n }\n\n body { min-height: 100vh; }\n\n .article-page {\n display: flex;\n flex-direction: column;\n min-height: 100vh;\n }\n\n .article-body {\n padding: 40px 28px 64px;\n display: flex;\n align-items: flex-start;\n gap: 36px;\n max-width: 1180px;\n margin: 0 auto;\n width: 100%;\n font-family: 'Inter', sans-serif;\n font-size: 15px;\n letter-spacing: 0.02em;\n color: var(--text-primary);\n }\n\n .article-body__main {\n flex: 1;\n min-width: 0;\n max-width: 820px;\n }\n\n .article__title {\n font-size: 24px;\n font-weight: 700;\n color: var(--text-primary);\n line-height: 1.3;\n margin-bottom: 8px;\n }\n\n .article__subtitle {\n font-size: 15px;\n color: var(--text-secondary);\n line-height: 1.75;\n margin-bottom: 24px;\n }\n\n .article__h2 {\n display: flex;\n align-items: center;\n gap: 9px;\n font-size: 17px;\n font-weight: 600;\n color: var(--text-primary);\n padding-bottom: 10px;\n border-bottom: 1px solid var(--border);\n margin-top: 28px;\n margin-bottom: 14px;\n }\n\n .article__h2-icon {\n display: flex;\n align-items: center;\n color: var(--green);\n }\n\n .article__p {\n font-size: 15px;\n color: var(--text-secondary);\n line-height: 1.8;\n margin-bottom: 14px;\n }\n\n .article__list {\n margin: 0 0 14px 0;\n padding-left: 20px;\n list-style: disc;\n }\n\n .article__list li {\n font-size: 14.5px;\n color: var(--text-secondary);\n line-height: 1.8;\n margin-bottom: 4px;\n }\n\n \/* ============================================================\n CALLOUT BOXES\n ============================================================ *\/\n .infobox {\n background: var(--green-xlight);\n border-left: 3px solid var(--green);\n border-radius: 0 var(--radius-md) var(--radius-md) 0;\n padding: 12px 16px;\n margin: 16px 0;\n }\n\n .infobox__title {\n display: flex;\n align-items: center;\n gap: 6px;\n font-size: 13px;\n font-weight: 600;\n color: var(--green-dark);\n margin-bottom: 5px;\n }\n\n .infobox__text {\n font-size: 13.5px;\n color: var(--green);\n line-height: 1.65;\n }\n\n .infobox--grey {\n background: var(--bg-muted);\n border-left-color: var(--border-mid);\n }\n\n .infobox--grey .infobox__title { color: var(--text-secondary); }\n .infobox--grey .infobox__text { color: var(--text-secondary); }\n\n .warnbox {\n background: var(--amber-light);\n border-left: 3px solid var(--amber);\n border-radius: 0 var(--radius-md) var(--radius-md) 0;\n padding: 12px 16px;\n margin: 16px 0;\n }\n\n .warnbox__title {\n display: flex;\n align-items: center;\n gap: 6px;\n font-size: 13px;\n font-weight: 600;\n color: #92400e;\n margin-bottom: 5px;\n }\n\n .warnbox__text {\n font-size: 13.5px;\n color: var(--amber);\n line-height: 1.65;\n }\n\n \/* ============================================================\n IMAGE\n ============================================================ *\/\n .article__figure {\n margin: 20px 0;\n text-align: center;\n }\n\n .article__figure img {\n max-width: 100%;\n }\n\n .article__figure figcaption {\n font-size: 13px;\n color: var(--text-muted);\n margin-top: 8px;\n }\n\n \/* ============================================================\n TABLE\n ============================================================ *\/\n .article__table-wrap {\n overflow-x: auto;\n margin: 16px 0;\n border-radius: var(--radius-md);\n border: 1px solid var(--border);\n }\n\n .article__table {\n width: 100%;\n border-collapse: collapse;\n font-size: 14px;\n }\n\n .article__table thead {\n background: var(--green);\n }\n\n .article__table th {\n text-align: left;\n font-weight: 600;\n color: #ffffff;\n padding: 10px 14px;\n border-bottom: 1px solid var(--border);\n white-space: nowrap;\n }\n\n .article__table td {\n padding: 10px 14px;\n color: var(--text-secondary);\n border-bottom: 1px solid var(--border);\n line-height: 1.6;\n vertical-align: top;\n }\n\n .article__table tr:last-child td { border-bottom: none; }\n\n .badge {\n display: inline-block;\n font-size: 12px;\n font-weight: 600;\n padding: 2px 8px;\n border-radius: 20px;\n background: var(--green-light);\n color: var(--green-dark);\n }\n\n \/* ============================================================\n RESPONSIVE\n ============================================================ *\/\n @media (max-width: 900px) {\n .article-body { flex-direction: column; padding: 20px 20px 48px; }\n }\n \n \/* Glossary tooltips *\/\n .glossary-term {\n border-bottom: 1px dotted var(--green);\n color: var(--green);\n font-style: italic;\n cursor: help;\n }\n .glossary-tooltip {\n position: fixed;\n z-index: 9999;\n background: #fff;\n border: 1px solid var(--border-mid);\n border-radius: var(--radius-md);\n box-shadow: var(--shadow-md);\n padding: 10px 14px;\n max-width: 300px;\n font-family: 'Inter', sans-serif;\n font-size: 13px;\n }\n .glossary-tooltip__title {\n font-weight: 600;\n color: var(--text-primary);\n margin-bottom: 4px;\n }\n .glossary-tooltip__def {\n font-size: 12.5px;\n color: var(--text-secondary);\n line-height: 1.6;\n }\n .glossary-tooltip__tag {\n display: inline-block;\n margin-top: 6px;\n font-size: 9px;\n font-weight: 600;\n padding: 2px 7px;\n border-radius: 20px;\n background: var(--green-light);\n color: var(--green-dark);\n text-transform: uppercase;\n letter-spacing: 0.04em;\n }\n\n <\/style>\n<\/head>\n<body>\n\n<div id=\"tt-angolo-di-pressione\" class=\"glossary-tooltip\" hidden=\"\">\n <div class=\"glossary-tooltip__title\">Pressure angle<\/div>\n <div class=\"glossary-tooltip__def\">Angle between the direction of the contact force between mating teeth and the tangent to the pitch circle at the point of contact. The standard value is 20\u00b0.<\/div>\n <span class=\"glossary-tooltip__tag\">Glossary<\/span>\n<\/div>\n<div id=\"tt-distanza-di-montaggio-md\" class=\"glossary-tooltip\" hidden=\"\">\n <div class=\"glossary-tooltip__title\">Mounting distance (MD)<\/div>\n <div class=\"glossary-tooltip__def\">Nominal distance between the reference plane of a bevel gear and the apex of the pitch cone. It determines correct axial positioning within the mating pair.<\/div>\n <span class=\"glossary-tooltip__tag\">Glossary<\/span>\n<\/div>\n\n <div class=\"article-page\">\n <div class=\"article-body\">\n <div class=\"article-body__main\"><script type=\"application\/ld+json\">\n{\n \"@context\": \"https:\/\/schema.org\",\n \"@graph\": [\n {\n \"@type\": \"TechArticle\",\n \"@id\": \"#article\",\n \"headline\": \"Interchangeability of bevel pairs: they're always replaced together\",\n \"description\": \"The time comes to replace a bevel pair: the pinion is worn, the gear wheel still seems good. You order only the pinion, mount it, put it back into service. After a few hours: abnormal noise, heating, accelerated wear. You've just paid twice for the same intervention.\",\n \"inLanguage\": \"en\",\n \"mentions\": [\n {\n \"@id\": \"#term-angolo-di-pressione\"\n },\n {\n \"@id\": \"#term-distanza-di-montaggio-md\"\n }\n ]\n },\n {\n \"@type\": \"DefinedTermSet\",\n \"@id\": \"#glossario\",\n \"name\": \"Glossario - Interchangeability of bevel pairs: they're always replaced together\",\n \"hasDefinedTerm\": [\n {\n \"@type\": \"DefinedTerm\",\n \"@id\": \"#term-angolo-di-pressione\",\n \"name\": \"Pressure angle\",\n \"description\": \"Angle between the direction of the contact force between mating teeth and the tangent to the pitch circle at the point of contact. The standard value is 20\u00b0.\",\n \"inDefinedTermSet\": \"#glossario\"\n },\n {\n \"@type\": \"DefinedTerm\",\n \"@id\": \"#term-distanza-di-montaggio-md\",\n \"name\": \"Mounting distance (MD)\",\n \"description\": \"Nominal distance between the reference plane of a bevel gear and the apex of the pitch cone. It determines correct axial positioning within the mating pair.\",\n \"inDefinedTermSet\": \"#glossario\"\n }\n ]\n }\n ]\n}\n<\/script>\n\n\n\n <h1 class=\"article__title\">Interchangeability of bevel pairs: they’re always replaced togetherr<\/h1>\n<p class=\"article__subtitle\">The time comes to replace a bevel pair: the pinion is worn, the gear wheel still seems good. You order only the pinion, mount it, put it back into service. After a few hours: abnormal noise, heating, accelerated wear. You’ve just paid twice for the same intervention.<\/p>\n<h2 class=\"article__h2\" id=\"the-rule-of-the-pair\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><polyline points=\"23 4 23 10 17 10\"><\/polyline><polyline points=\"1 20 1 14 7 14\"><\/polyline><path d=\"M3.51 9a9 9 0 0 1 14.85-3.36L23 10M1 14l4.64 4.36A9 9 0 0 0 20.49 15\"><\/path><\/svg><\/span>\n The rule of the pair\n<\/h2>\n<p class=\"article__p\"><strong>Pinion<\/strong> and <strong>gear wheel<\/strong> of a bevel pair are always replaced together. Never a single component, regardless of who made them. This rule holds between different manufacturers, but it also holds between gears from the same manufacturer, the same model and the same batch.<\/p>\n<p class=\"article__p\">Bevel pairs are produced and tested together, as a pair. Mixing components from different batches or suppliers means giving up that verification and accepting the risk of a pairing that doesn’t work as expected.<\/p>\n<h2 class=\"article__h2\" id=\"hidden-variations-between-manufacturers\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M10.29 3.86L1.82 18a2 2 0 0 0 1.71 3h16.94a2 2 0 0 0 1.71-3L13.71 3.86a2 2 0 0 0-3.42 0z\"><\/path><line x1=\"12\" y1=\"9\" x2=\"12\" y2=\"13\"><\/line><line x1=\"12\" y1=\"17\" x2=\"12.01\" y2=\"17\"><\/line><\/svg><\/span>\n Hidden variations between manufacturers\n<\/h2>\n<p class=\"article__p\">Two bevel pairs with the same module, the same tooth count and the same <strong><dfn id=\"def-angolo-di-pressione\"><span class=\"glossary-term\" data-tooltip=\"tt-angolo-di-pressione\" title=\"Angle between the direction of the contact force between mating teeth and the tangent to the pitch circle at the point of contact. The standard value is 20\u00b0.\">pressure angle<\/span><\/dfn><\/strong> seem interchangeable. In reality each manufacturer can set a series of parameters differently: the depth of the back cone, the pitch-cone angle, the position of the tooth foot, the tolerances on hub and bore. Even small differences in these values shift the contact zone between teeth.<\/p>\n<p class=\"article__p\">A Stagnoli pinion paired with a gear wheel from another manufacturer, even if compatible on paper, can produce contact on the tip or on the heel instead of centered. The result is visible after a few hours: noise, heating and early wear.<\/p>\n<div class=\"warnbox\">\n <div class=\"warnbox__title\">\n <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M10.29 3.86L1.82 18a2 2 0 0 0 1.71 3h16.94a2 2 0 0 0 1.71-3L13.71 3.86a2 2 0 0 0-3.42 0z\"><\/path><line x1=\"12\" y1=\"9\" x2=\"12\" y2=\"13\"><\/line><line x1=\"12\" y1=\"17\" x2=\"12.01\" y2=\"17\"><\/line><\/svg>\n Warning\n <\/div>\n <p class=\"warnbox__text\">Geometric compatibility on paper doesn’t mean correct pairing in service. The parameters that determine the contact zone don’t appear in standard catalogs.<\/p>\n<\/div>\n<h2 class=\"article__h2\" id=\"batch-and-mold-variations\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><polygon points=\"12 2 2 7 12 12 22 7 12 2\"><\/polygon><polyline points=\"2 17 12 22 22 17\"><\/polyline><polyline points=\"2 12 12 17 22 12\"><\/polyline><\/svg><\/span>\n Batch and mold variations\n<\/h2>\n<p class=\"article__p\">Even among pairs from the same manufacturer there are micro-variations linked to mold wear, differences between raw-material batches and the natural tolerances of molding.<\/p>\n<p class=\"article__p\">After a few hundred hours of operation, pinion and gear wheel run in against each other: the teeth carve a reciprocal contact pattern adapted to the pair. Replacing only one of the two means pairing a new tooth with an already run-in tooth. The contact surface shrinks, the local pressure rises and the new component wears out much sooner than it should.<\/p>\n<h2 class=\"article__h2\" id=\"correct-replacement-procedure\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><polyline points=\"9 11 12 14 22 4\"><\/polyline><path d=\"M21 12v7a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V5a2 2 0 0 1 2-2h11\"><\/path><\/svg><\/span>\n Correct replacement procedure\n<\/h2>\n<p class=\"article__p\">When a bevel pair is to be replaced:<\/p>\n<ol class=\"article__list\">\n <li>Disassemble both gears.<\/li>\n <li>Order a complete new set, pinion and gear wheel with the same code and, if possible, the same batch.<\/li>\n <li>Mount respecting the <strong><dfn id=\"def-distanza-di-montaggio-md\"><span class=\"glossary-term\" data-tooltip=\"tt-distanza-di-montaggio-md\" title=\"Nominal distance between the reference plane of a bevel gear and the apex of the pitch cone. It determines correct axial positioning within the mating pair.\">mounting distance (MD)<\/span><\/dfn><\/strong> indicated on the drawing.<\/li>\n <li>Verify the contact with the <strong>Prussian blue method<\/strong>: spread a thin layer of colored paste on the teeth of one of the gears, rotate the pair by hand for a few turns and read the pattern left on the other gear. A centered pattern covering <strong>50-70%<\/strong> of the tooth width indicates correct contact. A pattern shifted toward the tip or the heel signals an axial-positioning error to correct before putting it back into service.<\/li>\n <li>Only after confirming the contact, put it back into service.<\/li>\n<\/ol>\n<div class=\"infobox infobox--grey\">\n <div class=\"infobox__title\">\n <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><line x1=\"9\" y1=\"18\" x2=\"15\" y2=\"18\"><\/line><line x1=\"10\" y1=\"22\" x2=\"14\" y2=\"22\"><\/line><path d=\"M15.09 14c.18-.98.65-1.74 1.41-2.5A4.65 4.65 0 0 0 18 8 6 6 0 0 0 6 8c0 1 .23 2.23 1.5 3.5A4.61 4.61 0 0 1 8.91 14\"><\/path><\/svg>\n From the field\n <\/div>\n <p class=\"infobox__text\">Replacing a single element to save money almost always costs more than the complete set: the new component wears out in a short time and you find yourself doing a second intervention shortly after the first.<\/p>\n<\/div>\n\n <\/div>\n <\/div>\n <\/div>\n\n\n<script>\n (function () {\n var hideTimers = {};\n function positionTooltip(trigger, tooltip) {\n var margin = 8;\n tooltip.style.visibility = 'hidden';\n tooltip.style.top = '-9999px';\n tooltip.style.left = '-9999px';\n tooltip.removeAttribute('hidden');\n var ttRect = tooltip.getBoundingClientRect();\n var trRect = trigger.getBoundingClientRect();\n var vw = window.innerWidth, vh = window.innerHeight;\n var top = trRect.bottom + margin;\n var left = trRect.left;\n if (top + ttRect.height + margin > vh) {\n var above = trRect.top - ttRect.height - margin;\n top = above >= margin ? above : Math.max(margin, vh - ttRect.height - margin);\n }\n if (left + ttRect.width + margin > vw) left = vw - ttRect.width - margin;\n if (left < margin) left = margin;\n tooltip.style.top = top + 'px';\n tooltip.style.left = left + 'px';\n tooltip.style.visibility = '';\n }\n function showTooltip(ttId, trigger) {\n if (hideTimers[ttId]) { clearTimeout(hideTimers[ttId]); hideTimers[ttId] = null; }\n positionTooltip(trigger, document.getElementById(ttId));\n }\n function hideTooltip(ttId) {\n hideTimers[ttId] = setTimeout(function () {\n var tt = document.getElementById(ttId);\n if (tt) tt.setAttribute('hidden', '');\n hideTimers[ttId] = null;\n }, 180);\n }\n function cancelHide(ttId) {\n if (hideTimers[ttId]) { clearTimeout(hideTimers[ttId]); hideTimers[ttId] = null; }\n }\n document.querySelectorAll('[data-tooltip]').forEach(function (trigger) {\n var ttId = trigger.getAttribute('data-tooltip');\n trigger.addEventListener('mouseenter', function () { showTooltip(ttId, trigger); });\n trigger.addEventListener('mouseleave', function () { hideTooltip(ttId); });\n });\n ['tt-angolo-di-pressione', 'tt-distanza-di-montaggio-md'].forEach(function (ttId) {\n var tt = document.getElementById(ttId);\n if (!tt) return;\n tt.addEventListener('mouseenter', function () { cancelHide(ttId); });\n tt.addEventListener('mouseleave', function () { hideTooltip(ttId); });\n });\n })();\n<\/script>\n\n<\/body><\/html>\n","protected":false},"excerpt":{"rendered":"<p>Matched wear dynamics and geometric constraints that make the partial replacement of a single bevel gear technically incorrect.<\/p>\n","protected":false},"parent":0,"template":"","meta":{"_acf_changed":false},"campo-applicazione":[5457],"categoria-ct":[5445],"class_list":["post-25601","centro-tecnico","type-centro-tecnico","status-publish","hentry","campo-applicazione-assembly","categoria-ct-s-torque-and-s-speed-bevel-gear-sets"],"acf":[],"yoast_head":"\n<title>Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop<\/title>\n<meta name=\"description\" content=\"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop\" \/>\n<meta property=\"og:description\" content=\"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/\" \/>\n<meta property=\"og:site_name\" content=\"Stagnoli Gears Shop\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/StagnoliGears\" \/>\n<meta property=\"article:modified_time\" content=\"2026-07-10T11:55:04+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/\",\"name\":\"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#website\"},\"datePublished\":\"2026-06-30T09:20:47+00:00\",\"dateModified\":\"2026-07-10T11:55:04+00:00\",\"description\":\"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Interchangeability of bevel pairs: they’re always replaced together\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#website\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/\",\"name\":\"Stagnoli\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#organization\",\"name\":\"Stagnoli Gears\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/wp-content\\\/uploads\\\/logo-stagnoli-shop.svg\",\"contentUrl\":\"https:\\\/\\\/shop.stagnoligears.com\\\/wp-content\\\/uploads\\\/logo-stagnoli-shop.svg\",\"width\":1,\"height\":1,\"caption\":\"Stagnoli Gears\"},\"image\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/StagnoliGears\",\"https:\\\/\\\/www.youtube.com\\\/@stagnoli_gears\",\"https:\\\/\\\/www.linkedin.com\\\/showcase\\\/stagnoli-gears\\\/\"]}]}<\/script>\n","yoast_head_json":{"title":"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop","description":"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","og_locale":"en_US","og_type":"article","og_title":"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop","og_description":"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.","og_url":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","og_site_name":"Stagnoli Gears Shop","article_publisher":"https:\/\/www.facebook.com\/StagnoliGears","article_modified_time":"2026-07-10T11:55:04+00:00","twitter_card":"summary_large_image","twitter_misc":{"Est. reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","url":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","name":"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop","isPartOf":{"@id":"https:\/\/shop.stagnoligears.com\/en\/#website"},"datePublished":"2026-06-30T09:20:47+00:00","dateModified":"2026-07-10T11:55:04+00:00","description":"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.","breadcrumb":{"@id":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/shop.stagnoligears.com\/en\/"},{"@type":"ListItem","position":2,"name":"Interchangeability of bevel pairs: they’re always replaced together"}]},{"@type":"WebSite","@id":"https:\/\/shop.stagnoligears.com\/en\/#website","url":"https:\/\/shop.stagnoligears.com\/en\/","name":"Stagnoli","description":"","publisher":{"@id":"https:\/\/shop.stagnoligears.com\/en\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/shop.stagnoligears.com\/en\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/shop.stagnoligears.com\/en\/#organization","name":"Stagnoli Gears","url":"https:\/\/shop.stagnoligears.com\/en\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/shop.stagnoligears.com\/en\/#\/schema\/logo\/image\/","url":"https:\/\/shop.stagnoligears.com\/wp-content\/uploads\/logo-stagnoli-shop.svg","contentUrl":"https:\/\/shop.stagnoligears.com\/wp-content\/uploads\/logo-stagnoli-shop.svg","width":1,"height":1,"caption":"Stagnoli Gears"},"image":{"@id":"https:\/\/shop.stagnoligears.com\/en\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/StagnoliGears","https:\/\/www.youtube.com\/@stagnoli_gears","https:\/\/www.linkedin.com\/showcase\/stagnoli-gears\/"]}]}},"_links":{"self":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/centro-tecnico\/25601","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/centro-tecnico"}],"about":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/types\/centro-tecnico"}],"wp:attachment":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/media?parent=25601"}],"wp:term":[{"taxonomy":"campo-applicazione","embeddable":true,"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/campo-applicazione?post=25601"},{"taxonomy":"categoria-ct","embeddable":true,"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/categoria-ct?post=25601"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}

{"id":25601,"date":"2026-06-30T11:20:47","date_gmt":"2026-06-30T09:20:47","guid":{"rendered":"https:\/\/shop.stagnoligears.com\/?post_type=centro-tecnico&p=25601"},"modified":"2026-07-10T13:55:04","modified_gmt":"2026-07-10T11:55:04","slug":"interchangeability-of-bevel-pairs-always-replaced-together","status":"publish","type":"centro-tecnico","link":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","title":{"rendered":"Interchangeability of bevel pairs: they’re always replaced together"},"content":{"rendered":"\n\n \n \n \n Interchangeability of bevel pairs: they’re always replaced together<\/title>\n\n <link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n <link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin=\"\">\n <link href=\"https:\/\/fonts.googleapis.com\/css2?family=Inter:wght@400;500;600;700&display=swap\" rel=\"stylesheet\">\n\n <style>\n *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }\n\n :root {\n --green: #1a6b3c;\n --green-dark: #0f4a28;\n --green-mid: #2d8a55;\n --green-light: #e8f4ed;\n --green-xlight: #f2faf5;\n --amber: #b45309;\n --amber-light: #fef3c7;\n\n --bg: #ffffff;\n --bg-soft: #f8f9fa;\n --bg-muted: #f1f3f5;\n --border: #e5e7eb;\n --border-mid: #d1d5db;\n\n --text-primary: #111827;\n --text-secondary: #4b5563;\n --text-muted: #9ca3af;\n\n --radius-sm: 6px;\n --radius-md: 8px;\n --radius-lg: 12px;\n --shadow-sm: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);\n --shadow-md: 0 4px 12px rgba(0,0,0,.08), 0 2px 4px rgba(0,0,0,.04);\n }\n\n body { min-height: 100vh; }\n\n .article-page {\n display: flex;\n flex-direction: column;\n min-height: 100vh;\n }\n\n .article-body {\n padding: 40px 28px 64px;\n display: flex;\n align-items: flex-start;\n gap: 36px;\n max-width: 1180px;\n margin: 0 auto;\n width: 100%;\n font-family: 'Inter', sans-serif;\n font-size: 15px;\n letter-spacing: 0.02em;\n color: var(--text-primary);\n }\n\n .article-body__main {\n flex: 1;\n min-width: 0;\n max-width: 820px;\n }\n\n .article__title {\n font-size: 24px;\n font-weight: 700;\n color: var(--text-primary);\n line-height: 1.3;\n margin-bottom: 8px;\n }\n\n .article__subtitle {\n font-size: 15px;\n color: var(--text-secondary);\n line-height: 1.75;\n margin-bottom: 24px;\n }\n\n .article__h2 {\n display: flex;\n align-items: center;\n gap: 9px;\n font-size: 17px;\n font-weight: 600;\n color: var(--text-primary);\n padding-bottom: 10px;\n border-bottom: 1px solid var(--border);\n margin-top: 28px;\n margin-bottom: 14px;\n }\n\n .article__h2-icon {\n display: flex;\n align-items: center;\n color: var(--green);\n }\n\n .article__p {\n font-size: 15px;\n color: var(--text-secondary);\n line-height: 1.8;\n margin-bottom: 14px;\n }\n\n .article__list {\n margin: 0 0 14px 0;\n padding-left: 20px;\n list-style: disc;\n }\n\n .article__list li {\n font-size: 14.5px;\n color: var(--text-secondary);\n line-height: 1.8;\n margin-bottom: 4px;\n }\n\n \/* ============================================================\n CALLOUT BOXES\n ============================================================ *\/\n .infobox {\n background: var(--green-xlight);\n border-left: 3px solid var(--green);\n border-radius: 0 var(--radius-md) var(--radius-md) 0;\n padding: 12px 16px;\n margin: 16px 0;\n }\n\n .infobox__title {\n display: flex;\n align-items: center;\n gap: 6px;\n font-size: 13px;\n font-weight: 600;\n color: var(--green-dark);\n margin-bottom: 5px;\n }\n\n .infobox__text {\n font-size: 13.5px;\n color: var(--green);\n line-height: 1.65;\n }\n\n .infobox--grey {\n background: var(--bg-muted);\n border-left-color: var(--border-mid);\n }\n\n .infobox--grey .infobox__title { color: var(--text-secondary); }\n .infobox--grey .infobox__text { color: var(--text-secondary); }\n\n .warnbox {\n background: var(--amber-light);\n border-left: 3px solid var(--amber);\n border-radius: 0 var(--radius-md) var(--radius-md) 0;\n padding: 12px 16px;\n margin: 16px 0;\n }\n\n .warnbox__title {\n display: flex;\n align-items: center;\n gap: 6px;\n font-size: 13px;\n font-weight: 600;\n color: #92400e;\n margin-bottom: 5px;\n }\n\n .warnbox__text {\n font-size: 13.5px;\n color: var(--amber);\n line-height: 1.65;\n }\n\n \/* ============================================================\n IMAGE\n ============================================================ *\/\n .article__figure {\n margin: 20px 0;\n text-align: center;\n }\n\n .article__figure img {\n max-width: 100%;\n }\n\n .article__figure figcaption {\n font-size: 13px;\n color: var(--text-muted);\n margin-top: 8px;\n }\n\n \/* ============================================================\n TABLE\n ============================================================ *\/\n .article__table-wrap {\n overflow-x: auto;\n margin: 16px 0;\n border-radius: var(--radius-md);\n border: 1px solid var(--border);\n }\n\n .article__table {\n width: 100%;\n border-collapse: collapse;\n font-size: 14px;\n }\n\n .article__table thead {\n background: var(--green);\n }\n\n .article__table th {\n text-align: left;\n font-weight: 600;\n color: #ffffff;\n padding: 10px 14px;\n border-bottom: 1px solid var(--border);\n white-space: nowrap;\n }\n\n .article__table td {\n padding: 10px 14px;\n color: var(--text-secondary);\n border-bottom: 1px solid var(--border);\n line-height: 1.6;\n vertical-align: top;\n }\n\n .article__table tr:last-child td { border-bottom: none; }\n\n .badge {\n display: inline-block;\n font-size: 12px;\n font-weight: 600;\n padding: 2px 8px;\n border-radius: 20px;\n background: var(--green-light);\n color: var(--green-dark);\n }\n\n \/* ============================================================\n RESPONSIVE\n ============================================================ *\/\n @media (max-width: 900px) {\n .article-body { flex-direction: column; padding: 20px 20px 48px; }\n }\n \n \/* Glossary tooltips *\/\n .glossary-term {\n border-bottom: 1px dotted var(--green);\n color: var(--green);\n font-style: italic;\n cursor: help;\n }\n .glossary-tooltip {\n position: fixed;\n z-index: 9999;\n background: #fff;\n border: 1px solid var(--border-mid);\n border-radius: var(--radius-md);\n box-shadow: var(--shadow-md);\n padding: 10px 14px;\n max-width: 300px;\n font-family: 'Inter', sans-serif;\n font-size: 13px;\n }\n .glossary-tooltip__title {\n font-weight: 600;\n color: var(--text-primary);\n margin-bottom: 4px;\n }\n .glossary-tooltip__def {\n font-size: 12.5px;\n color: var(--text-secondary);\n line-height: 1.6;\n }\n .glossary-tooltip__tag {\n display: inline-block;\n margin-top: 6px;\n font-size: 9px;\n font-weight: 600;\n padding: 2px 7px;\n border-radius: 20px;\n background: var(--green-light);\n color: var(--green-dark);\n text-transform: uppercase;\n letter-spacing: 0.04em;\n }\n\n <\/style>\n<\/head>\n<body>\n\n<div id=\"tt-angolo-di-pressione\" class=\"glossary-tooltip\" hidden=\"\">\n <div class=\"glossary-tooltip__title\">Pressure angle<\/div>\n <div class=\"glossary-tooltip__def\">Angle between the direction of the contact force between mating teeth and the tangent to the pitch circle at the point of contact. The standard value is 20\u00b0.<\/div>\n <span class=\"glossary-tooltip__tag\">Glossary<\/span>\n<\/div>\n<div id=\"tt-distanza-di-montaggio-md\" class=\"glossary-tooltip\" hidden=\"\">\n <div class=\"glossary-tooltip__title\">Mounting distance (MD)<\/div>\n <div class=\"glossary-tooltip__def\">Nominal distance between the reference plane of a bevel gear and the apex of the pitch cone. It determines correct axial positioning within the mating pair.<\/div>\n <span class=\"glossary-tooltip__tag\">Glossary<\/span>\n<\/div>\n\n <div class=\"article-page\">\n <div class=\"article-body\">\n <div class=\"article-body__main\"><script type=\"application\/ld+json\">\n{\n \"@context\": \"https:\/\/schema.org\",\n \"@graph\": [\n {\n \"@type\": \"TechArticle\",\n \"@id\": \"#article\",\n \"headline\": \"Interchangeability of bevel pairs: they're always replaced together\",\n \"description\": \"The time comes to replace a bevel pair: the pinion is worn, the gear wheel still seems good. You order only the pinion, mount it, put it back into service. After a few hours: abnormal noise, heating, accelerated wear. You've just paid twice for the same intervention.\",\n \"inLanguage\": \"en\",\n \"mentions\": [\n {\n \"@id\": \"#term-angolo-di-pressione\"\n },\n {\n \"@id\": \"#term-distanza-di-montaggio-md\"\n }\n ]\n },\n {\n \"@type\": \"DefinedTermSet\",\n \"@id\": \"#glossario\",\n \"name\": \"Glossario - Interchangeability of bevel pairs: they're always replaced together\",\n \"hasDefinedTerm\": [\n {\n \"@type\": \"DefinedTerm\",\n \"@id\": \"#term-angolo-di-pressione\",\n \"name\": \"Pressure angle\",\n \"description\": \"Angle between the direction of the contact force between mating teeth and the tangent to the pitch circle at the point of contact. The standard value is 20\u00b0.\",\n \"inDefinedTermSet\": \"#glossario\"\n },\n {\n \"@type\": \"DefinedTerm\",\n \"@id\": \"#term-distanza-di-montaggio-md\",\n \"name\": \"Mounting distance (MD)\",\n \"description\": \"Nominal distance between the reference plane of a bevel gear and the apex of the pitch cone. It determines correct axial positioning within the mating pair.\",\n \"inDefinedTermSet\": \"#glossario\"\n }\n ]\n }\n ]\n}\n<\/script>\n\n\n\n <h1 class=\"article__title\">Interchangeability of bevel pairs: they’re always replaced togetherr<\/h1>\n<p class=\"article__subtitle\">The time comes to replace a bevel pair: the pinion is worn, the gear wheel still seems good. You order only the pinion, mount it, put it back into service. After a few hours: abnormal noise, heating, accelerated wear. You’ve just paid twice for the same intervention.<\/p>\n<h2 class=\"article__h2\" id=\"the-rule-of-the-pair\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><polyline points=\"23 4 23 10 17 10\"><\/polyline><polyline points=\"1 20 1 14 7 14\"><\/polyline><path d=\"M3.51 9a9 9 0 0 1 14.85-3.36L23 10M1 14l4.64 4.36A9 9 0 0 0 20.49 15\"><\/path><\/svg><\/span>\n The rule of the pair\n<\/h2>\n<p class=\"article__p\"><strong>Pinion<\/strong> and <strong>gear wheel<\/strong> of a bevel pair are always replaced together. Never a single component, regardless of who made them. This rule holds between different manufacturers, but it also holds between gears from the same manufacturer, the same model and the same batch.<\/p>\n<p class=\"article__p\">Bevel pairs are produced and tested together, as a pair. Mixing components from different batches or suppliers means giving up that verification and accepting the risk of a pairing that doesn’t work as expected.<\/p>\n<h2 class=\"article__h2\" id=\"hidden-variations-between-manufacturers\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M10.29 3.86L1.82 18a2 2 0 0 0 1.71 3h16.94a2 2 0 0 0 1.71-3L13.71 3.86a2 2 0 0 0-3.42 0z\"><\/path><line x1=\"12\" y1=\"9\" x2=\"12\" y2=\"13\"><\/line><line x1=\"12\" y1=\"17\" x2=\"12.01\" y2=\"17\"><\/line><\/svg><\/span>\n Hidden variations between manufacturers\n<\/h2>\n<p class=\"article__p\">Two bevel pairs with the same module, the same tooth count and the same <strong><dfn id=\"def-angolo-di-pressione\"><span class=\"glossary-term\" data-tooltip=\"tt-angolo-di-pressione\" title=\"Angle between the direction of the contact force between mating teeth and the tangent to the pitch circle at the point of contact. The standard value is 20\u00b0.\">pressure angle<\/span><\/dfn><\/strong> seem interchangeable. In reality each manufacturer can set a series of parameters differently: the depth of the back cone, the pitch-cone angle, the position of the tooth foot, the tolerances on hub and bore. Even small differences in these values shift the contact zone between teeth.<\/p>\n<p class=\"article__p\">A Stagnoli pinion paired with a gear wheel from another manufacturer, even if compatible on paper, can produce contact on the tip or on the heel instead of centered. The result is visible after a few hours: noise, heating and early wear.<\/p>\n<div class=\"warnbox\">\n <div class=\"warnbox__title\">\n <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><path d=\"M10.29 3.86L1.82 18a2 2 0 0 0 1.71 3h16.94a2 2 0 0 0 1.71-3L13.71 3.86a2 2 0 0 0-3.42 0z\"><\/path><line x1=\"12\" y1=\"9\" x2=\"12\" y2=\"13\"><\/line><line x1=\"12\" y1=\"17\" x2=\"12.01\" y2=\"17\"><\/line><\/svg>\n Warning\n <\/div>\n <p class=\"warnbox__text\">Geometric compatibility on paper doesn’t mean correct pairing in service. The parameters that determine the contact zone don’t appear in standard catalogs.<\/p>\n<\/div>\n<h2 class=\"article__h2\" id=\"batch-and-mold-variations\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><polygon points=\"12 2 2 7 12 12 22 7 12 2\"><\/polygon><polyline points=\"2 17 12 22 22 17\"><\/polyline><polyline points=\"2 12 12 17 22 12\"><\/polyline><\/svg><\/span>\n Batch and mold variations\n<\/h2>\n<p class=\"article__p\">Even among pairs from the same manufacturer there are micro-variations linked to mold wear, differences between raw-material batches and the natural tolerances of molding.<\/p>\n<p class=\"article__p\">After a few hundred hours of operation, pinion and gear wheel run in against each other: the teeth carve a reciprocal contact pattern adapted to the pair. Replacing only one of the two means pairing a new tooth with an already run-in tooth. The contact surface shrinks, the local pressure rises and the new component wears out much sooner than it should.<\/p>\n<h2 class=\"article__h2\" id=\"correct-replacement-procedure\">\n <span class=\"article__h2-icon\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><polyline points=\"9 11 12 14 22 4\"><\/polyline><path d=\"M21 12v7a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2V5a2 2 0 0 1 2-2h11\"><\/path><\/svg><\/span>\n Correct replacement procedure\n<\/h2>\n<p class=\"article__p\">When a bevel pair is to be replaced:<\/p>\n<ol class=\"article__list\">\n <li>Disassemble both gears.<\/li>\n <li>Order a complete new set, pinion and gear wheel with the same code and, if possible, the same batch.<\/li>\n <li>Mount respecting the <strong><dfn id=\"def-distanza-di-montaggio-md\"><span class=\"glossary-term\" data-tooltip=\"tt-distanza-di-montaggio-md\" title=\"Nominal distance between the reference plane of a bevel gear and the apex of the pitch cone. It determines correct axial positioning within the mating pair.\">mounting distance (MD)<\/span><\/dfn><\/strong> indicated on the drawing.<\/li>\n <li>Verify the contact with the <strong>Prussian blue method<\/strong>: spread a thin layer of colored paste on the teeth of one of the gears, rotate the pair by hand for a few turns and read the pattern left on the other gear. A centered pattern covering <strong>50-70%<\/strong> of the tooth width indicates correct contact. A pattern shifted toward the tip or the heel signals an axial-positioning error to correct before putting it back into service.<\/li>\n <li>Only after confirming the contact, put it back into service.<\/li>\n<\/ol>\n<div class=\"infobox infobox--grey\">\n <div class=\"infobox__title\">\n <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" stroke-linecap=\"round\" stroke-linejoin=\"round\"><line x1=\"9\" y1=\"18\" x2=\"15\" y2=\"18\"><\/line><line x1=\"10\" y1=\"22\" x2=\"14\" y2=\"22\"><\/line><path d=\"M15.09 14c.18-.98.65-1.74 1.41-2.5A4.65 4.65 0 0 0 18 8 6 6 0 0 0 6 8c0 1 .23 2.23 1.5 3.5A4.61 4.61 0 0 1 8.91 14\"><\/path><\/svg>\n From the field\n <\/div>\n <p class=\"infobox__text\">Replacing a single element to save money almost always costs more than the complete set: the new component wears out in a short time and you find yourself doing a second intervention shortly after the first.<\/p>\n<\/div>\n\n <\/div>\n <\/div>\n <\/div>\n\n\n<script>\n (function () {\n var hideTimers = {};\n function positionTooltip(trigger, tooltip) {\n var margin = 8;\n tooltip.style.visibility = 'hidden';\n tooltip.style.top = '-9999px';\n tooltip.style.left = '-9999px';\n tooltip.removeAttribute('hidden');\n var ttRect = tooltip.getBoundingClientRect();\n var trRect = trigger.getBoundingClientRect();\n var vw = window.innerWidth, vh = window.innerHeight;\n var top = trRect.bottom + margin;\n var left = trRect.left;\n if (top + ttRect.height + margin > vh) {\n var above = trRect.top - ttRect.height - margin;\n top = above >= margin ? above : Math.max(margin, vh - ttRect.height - margin);\n }\n if (left + ttRect.width + margin > vw) left = vw - ttRect.width - margin;\n if (left < margin) left = margin;\n tooltip.style.top = top + 'px';\n tooltip.style.left = left + 'px';\n tooltip.style.visibility = '';\n }\n function showTooltip(ttId, trigger) {\n if (hideTimers[ttId]) { clearTimeout(hideTimers[ttId]); hideTimers[ttId] = null; }\n positionTooltip(trigger, document.getElementById(ttId));\n }\n function hideTooltip(ttId) {\n hideTimers[ttId] = setTimeout(function () {\n var tt = document.getElementById(ttId);\n if (tt) tt.setAttribute('hidden', '');\n hideTimers[ttId] = null;\n }, 180);\n }\n function cancelHide(ttId) {\n if (hideTimers[ttId]) { clearTimeout(hideTimers[ttId]); hideTimers[ttId] = null; }\n }\n document.querySelectorAll('[data-tooltip]').forEach(function (trigger) {\n var ttId = trigger.getAttribute('data-tooltip');\n trigger.addEventListener('mouseenter', function () { showTooltip(ttId, trigger); });\n trigger.addEventListener('mouseleave', function () { hideTooltip(ttId); });\n });\n ['tt-angolo-di-pressione', 'tt-distanza-di-montaggio-md'].forEach(function (ttId) {\n var tt = document.getElementById(ttId);\n if (!tt) return;\n tt.addEventListener('mouseenter', function () { cancelHide(ttId); });\n tt.addEventListener('mouseleave', function () { hideTooltip(ttId); });\n });\n })();\n<\/script>\n\n<\/body><\/html>\n","protected":false},"excerpt":{"rendered":"<p>Matched wear dynamics and geometric constraints that make the partial replacement of a single bevel gear technically incorrect.<\/p>\n","protected":false},"parent":0,"template":"","meta":{"_acf_changed":false},"campo-applicazione":[5457],"categoria-ct":[5445],"class_list":["post-25601","centro-tecnico","type-centro-tecnico","status-publish","hentry","campo-applicazione-assembly","categoria-ct-s-torque-and-s-speed-bevel-gear-sets"],"acf":[],"yoast_head":"\n<title>Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop<\/title>\n<meta name=\"description\" content=\"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop\" \/>\n<meta property=\"og:description\" content=\"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/\" \/>\n<meta property=\"og:site_name\" content=\"Stagnoli Gears Shop\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/StagnoliGears\" \/>\n<meta property=\"article:modified_time\" content=\"2026-07-10T11:55:04+00:00\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"3 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/\",\"name\":\"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#website\"},\"datePublished\":\"2026-06-30T09:20:47+00:00\",\"dateModified\":\"2026-07-10T11:55:04+00:00\",\"description\":\"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/technical-hub\\\/interchangeability-of-bevel-pairs-always-replaced-together\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Interchangeability of bevel pairs: they’re always replaced together\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#website\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/\",\"name\":\"Stagnoli\",\"description\":\"\",\"publisher\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#organization\"},\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/?s={search_term_string}\"},\"query-input\":{\"@type\":\"PropertyValueSpecification\",\"valueRequired\":true,\"valueName\":\"search_term_string\"}}],\"inLanguage\":\"en-US\"},{\"@type\":\"Organization\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#organization\",\"name\":\"Stagnoli Gears\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/\",\"logo\":{\"@type\":\"ImageObject\",\"inLanguage\":\"en-US\",\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#\\\/schema\\\/logo\\\/image\\\/\",\"url\":\"https:\\\/\\\/shop.stagnoligears.com\\\/wp-content\\\/uploads\\\/logo-stagnoli-shop.svg\",\"contentUrl\":\"https:\\\/\\\/shop.stagnoligears.com\\\/wp-content\\\/uploads\\\/logo-stagnoli-shop.svg\",\"width\":1,\"height\":1,\"caption\":\"Stagnoli Gears\"},\"image\":{\"@id\":\"https:\\\/\\\/shop.stagnoligears.com\\\/en\\\/#\\\/schema\\\/logo\\\/image\\\/\"},\"sameAs\":[\"https:\\\/\\\/www.facebook.com\\\/StagnoliGears\",\"https:\\\/\\\/www.youtube.com\\\/@stagnoli_gears\",\"https:\\\/\\\/www.linkedin.com\\\/showcase\\\/stagnoli-gears\\\/\"]}]}<\/script>\n","yoast_head_json":{"title":"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop","description":"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","og_locale":"en_US","og_type":"article","og_title":"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop","og_description":"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.","og_url":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","og_site_name":"Stagnoli Gears Shop","article_publisher":"https:\/\/www.facebook.com\/StagnoliGears","article_modified_time":"2026-07-10T11:55:04+00:00","twitter_card":"summary_large_image","twitter_misc":{"Est. reading time":"3 minutes"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","url":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/","name":"Bevel Gear Pairs: Always Replace Together | Stagnoli Gears Shop","isPartOf":{"@id":"https:\/\/shop.stagnoligears.com\/en\/#website"},"datePublished":"2026-06-30T09:20:47+00:00","dateModified":"2026-07-10T11:55:04+00:00","description":"Learn why bevel gear pairs must always be replaced together and how mixing pinions and gears can cause noise, overheating and premature wear.","breadcrumb":{"@id":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/#breadcrumb"},"inLanguage":"en-US","potentialAction":[{"@type":"ReadAction","target":["https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/shop.stagnoligears.com\/en\/technical-hub\/interchangeability-of-bevel-pairs-always-replaced-together\/#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https:\/\/shop.stagnoligears.com\/en\/"},{"@type":"ListItem","position":2,"name":"Interchangeability of bevel pairs: they’re always replaced together"}]},{"@type":"WebSite","@id":"https:\/\/shop.stagnoligears.com\/en\/#website","url":"https:\/\/shop.stagnoligears.com\/en\/","name":"Stagnoli","description":"","publisher":{"@id":"https:\/\/shop.stagnoligears.com\/en\/#organization"},"potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/shop.stagnoligears.com\/en\/?s={search_term_string}"},"query-input":{"@type":"PropertyValueSpecification","valueRequired":true,"valueName":"search_term_string"}}],"inLanguage":"en-US"},{"@type":"Organization","@id":"https:\/\/shop.stagnoligears.com\/en\/#organization","name":"Stagnoli Gears","url":"https:\/\/shop.stagnoligears.com\/en\/","logo":{"@type":"ImageObject","inLanguage":"en-US","@id":"https:\/\/shop.stagnoligears.com\/en\/#\/schema\/logo\/image\/","url":"https:\/\/shop.stagnoligears.com\/wp-content\/uploads\/logo-stagnoli-shop.svg","contentUrl":"https:\/\/shop.stagnoligears.com\/wp-content\/uploads\/logo-stagnoli-shop.svg","width":1,"height":1,"caption":"Stagnoli Gears"},"image":{"@id":"https:\/\/shop.stagnoligears.com\/en\/#\/schema\/logo\/image\/"},"sameAs":["https:\/\/www.facebook.com\/StagnoliGears","https:\/\/www.youtube.com\/@stagnoli_gears","https:\/\/www.linkedin.com\/showcase\/stagnoli-gears\/"]}]}},"_links":{"self":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/centro-tecnico\/25601","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/centro-tecnico"}],"about":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/types\/centro-tecnico"}],"wp:attachment":[{"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/media?parent=25601"}],"wp:term":[{"taxonomy":"campo-applicazione","embeddable":true,"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/campo-applicazione?post=25601"},{"taxonomy":"categoria-ct","embeddable":true,"href":"https:\/\/shop.stagnoligears.com\/en\/wp-json\/wp\/v2\/categoria-ct?post=25601"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}