{"id":1072,"date":"2026-10-09T02:47:53","date_gmt":"2026-10-09T02:47:53","guid":{"rendered":"https:\/\/sun-gears.net\/how-to-choose-sun-gear-planetary-gearbox\/"},"modified":"2026-10-09T05:44:37","modified_gmt":"2026-10-09T05:44:37","slug":"how-to-choose-sun-gear-planetary-gearbox","status":"publish","type":"post","link":"https:\/\/sun-gears.net\/kk\/how-to-choose-sun-gear-planetary-gearbox\/","title":{"rendered":"How to Choose the Right Sun Gear for a Planetary Gearbox"},"content":{"rendered":"
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KNOWLEDGE<\/div>\n

How to Choose the Right Sun Gear for a Planetary Gearbox<\/h1>\n

The right sun gear is selected from the complete planetary geometry, center interface, operating duty and inspection needs\u2014not from diameter alone.<\/p>\n

Technical Guide<\/span>Sun Gear<\/span>Planetary Gear<\/span><\/div>\n
Request a Quote<\/a>Knowledge Center<\/a><\/div>\n<\/div>\n
\"How<\/figure>\n<\/div>\n<\/section>\n
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Why this topic changes the sun gear decision<\/h2>\n<\/div>\n
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The first step is to define system-level sun gear selection in the context of the complete planetary stage. Sun, planet and ring gear tooth data share one center-distance relationship, and the number of planets can add assembly constraints.<\/p>\n

Changing one sun-gear variable can alter ratio, contact, packaging or the mating gear requirements. Preserve the controlled calculation for replacement work and use a system-level review for new designs.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

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Practical design and replacement implications<\/h2>\n<\/div>\n
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Start with tooth count, module or DP, pressure angle, helix information and any specified profile shift. Then add planet and ring tooth counts and the number of planets.<\/p>\n

The center connection\u2014bore, key, spline, hollow center or integrated shaft\u2014should be defined after the mesh is understood, not treated as a separate cosmetic feature.<\/p>\n<\/div>\n

\"Practical<\/figure>\n<\/div>\n<\/div>\n<\/section>\n
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What to control on the RFQ or drawing<\/h2>\n<\/div>\n
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Item<\/th>\nWhat to define<\/th>\n<\/tr>\n<\/thead>\n
Tooth system<\/td>\nTooth count, module\/DP, pressure angle, helix and profile shift\/modification when applicable.<\/td>\n<\/tr>\n
Planetary context<\/td>\nMating planet\/ring data and planet count when available.<\/td>\n<\/tr>\n
Center interface<\/td>\nBore, keyway, spline, hollow center or integrated shaft plus functional datums.<\/td>\n<\/tr>\n
Duty<\/td>\nRated\/peak torque, speed, reversals\/shock, life, lubrication and environment.<\/td>\n<\/tr>\n
Process<\/td>\nControlled material, heat treatment, finishing and coating requirements.<\/td>\n<\/tr>\n
Acceptance<\/td>\nTooth\/runout\/dimensional inspection and required documentation.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n<\/section>\n
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A practical product-interface example<\/h2>\n<\/div>\n
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A planetary design may use several center connections. When torque must be carried through a compact toothed interface, splined sun gears<\/a> are a natural option to compare with keyed bores or integrated sun gear shafts, especially when compact torque transfer and repeatable alignment are important.<\/p>\n

The final choice should still follow torque, engagement length, alignment, service access and the controlled planetary drawing.<\/p>\n<\/div>\n<\/div>\n<\/section>\n

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Frequently asked questions<\/h2>\n<\/div>\n
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\nCan one loose sun gear answer every design question?<\/summary>\n

Usually not. Mating gear data and the center interface provide important cross-checks.<\/p>\n<\/details>\n

\nShould material or tolerance be copied from a similar part?<\/summary>\n

Only when the controlled design allows it. Similar appearance is not proof of the same duty or specification.<\/p>\n<\/details>\n

\nWhat is the fastest way to get a useful quote?<\/summary>\n

Send the latest drawing or measured tooth\/interface data, mating component information, duty, acceptance needs and quantity.<\/p>\n<\/details>\n<\/div>\n<\/div>\n<\/section>\n

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\u0421\u04b1\u0440\u0430\u043d\u044b\u0441 \u0431\u043e\u0439\u044b\u043d\u0448\u0430 \u0441\u04b1\u0440\u0430\u049b\u0442\u0430\u0440<\/div>\n

\u0411\u0430\u0493\u0430 \u0441\u04b1\u0440\u0430\u0443 \/ RFQ \u0436\u0456\u0431\u0435\u0440\u0443<\/h2>\n

Send the drawing, mating gear information, center interface, duty, inspection needs and quantity. The article is selection guidance; the approved drawing controls production.<\/p>\n

Send RFQ<\/a><\/div>\n

MOQ<\/strong>\u04e8\u043d\u0456\u043c \u0442\u04af\u0440\u0456\u043d\u0435 \u0436\u04d9\u043d\u0435 \u0442\u0430\u043f\u0441\u044b\u0440\u044b\u0441\u0442\u044b\u04a3 \u0436\u0430\u043b\u043f\u044b \u049b\u04b1\u043d\u044b\u043d\u0430 \u049b\u0430\u0440\u0430\u0439 \u0438\u043a\u0435\u043c\u0434\u0456.<\/span><\/div>
\u04ae\u043b\u0433\u0456\u043b\u0435\u0440<\/strong>New customers may request 1-5 pieces when the part and process are suitable.<\/span><\/div>
\u0410\u0440\u0430\u043b\u0430\u0441 \u0442\u0430\u043f\u0441\u044b\u0440\u044b\u0441\u0442\u0430\u0440<\/strong>Different sun gear or related planetary-component models can be combined when the total order value is around USD 1,500 or above.<\/span><\/div>
\u0428\u0430\u0493\u044b\u043d \u0442\u0430\u043f\u0441\u044b\u0440\u044b\u0441\u0442\u0430\u0440<\/strong>Orders from 1-2 pieces can be discussed, normally with a higher unit cost.<\/span><\/div>
\u0416\u0435\u0442\u043a\u0456\u0437\u0443<\/strong>Standard parts: 10-25 working days. Custom components: 20-45 working days. Project equipment: 45-120 working days.<\/span><\/div>
\u0421\u0430\u0443\u0434\u0430 \u0448\u0430\u0440\u0442\u0442\u0430\u0440\u044b<\/strong>EXW, FOB, CIF \u0436\u04d9\u043d\u0435 DAP \u04d9\u0434\u0435\u0442\u0442\u0435 \u049b\u043e\u043b\u0434\u0430\u0443 \u043a\u04e9\u0440\u0441\u0435\u0442\u0456\u043b\u0435\u0434\u0456. FCA, CFR, CPT, CIP \u0436\u04d9\u043d\u0435 DDP \u04d9\u0440 \u0436\u0430\u0493\u0434\u0430\u0439\u0434\u044b \u0436\u0435\u043a\u0435 \u0442\u0430\u043b\u049b\u044b\u043b\u0430\u0443\u0493\u0430 \u0431\u043e\u043b\u0430\u0434\u044b.<\/span><\/div><\/div><\/div>\n<\/div>\n<\/section>","protected":false},"excerpt":{"rendered":"

The right sun gear is selected from the complete planetary geometry, center interface, operating duty and inspection needs\u2014not from diameter alone.<\/p>","protected":false},"author":1,"featured_media":1097,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1072","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-sun-gears"],"_links":{"self":[{"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/posts\/1072","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/comments?post=1072"}],"version-history":[{"count":1,"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/posts\/1072\/revisions"}],"predecessor-version":[{"id":1118,"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/posts\/1072\/revisions\/1118"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/media\/1097"}],"wp:attachment":[{"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/media?parent=1072"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/categories?post=1072"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sun-gears.net\/kk\/wp-json\/wp\/v2\/tags?post=1072"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}