{"id":1075,"date":"2026-10-09T02:48:16","date_gmt":"2026-10-09T02:48:16","guid":{"rendered":"https:\/\/sun-gears.net\/sun-gear-runout-concentricity\/"},"modified":"2026-10-09T05:45:07","modified_gmt":"2026-10-09T05:45:07","slug":"sun-gear-runout-concentricity","status":"publish","type":"post","link":"https:\/\/sun-gears.net\/hi\/sun-gear-runout-concentricity\/","title":{"rendered":"Sun Gear Runout and Concentricity: Why Datums Matter"},"content":{"rendered":"
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KNOWLEDGE<\/div>\n

Sun Gear Runout and Concentricity: Why Datums Matter<\/h1>\n

Runout only has meaning relative to the surface that defines the operating axis. On a sun gear, that datum may be a bore, spline, shaft or bearing seat.<\/p>\n

Technical Guide<\/span>Sun Gear<\/span>Planetary Gear<\/span><\/div>\n
\u090f\u0915 \u0909\u0926\u094d\u0927\u0930\u0923 \u0915\u093e \u0905\u0928\u0941\u0930\u094b\u0927 \u0915\u0930\u0947\u0902<\/a>Knowledge Center<\/a><\/div>\n<\/div>\n
\"Sun<\/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 useful manufacturing question is how runout, coaxiality and datum control protects the function defined on the drawing. Process names are not quality levels by themselves; the required tooth, runout, hardness and interface results are what matter.<\/p>\n

Heat treatment can move the part, so machining allowance and final datum recovery should be planned before hardening when tight gear, bore or shaft relationships are required.<\/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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Inspection should match the acceptance plan. Tooth-size checks, runout, profile\/lead, hardness and dimensional measurements are selected according to the drawing and application rather than applied as a generic bundle.<\/p>\n

If reports or certificates are required, state them at RFQ stage so the manufacturing and sampling plan can include them.<\/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
\n\n\n\n\n\n\n\n\n\n\n
\u0935\u0938\u094d\u0924\u0941<\/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
\u0915\u0930\u094d\u0924\u0935\u094d\u092f<\/td>\nRated\/peak torque, speed, reversals\/shock, life, lubrication and environment.<\/td>\n<\/tr>\n
\u092a\u094d\u0930\u0915\u094d\u0930\u093f\u092f\u093e<\/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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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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\u0906\u0930\u090f\u092b\u0915\u094d\u092f\u0942<\/div>\n

\u0915\u094b\u091f\u0947\u0936\u0928 \u0915\u093e \u0905\u0928\u0941\u0930\u094b\u0927 \u0915\u0930\u0947\u0902 \/ \u0906\u0930\u090f\u092b\u0915\u094d\u092f\u0942 \u092d\u0947\u091c\u0947\u0902<\/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

\u0906\u0930\u090f\u092b\u0915\u094d\u092f\u0942 \u092d\u0947\u091c\u0947\u0902<\/a><\/div>\n

\u0928\u094d\u092f\u0942\u0928\u0924\u092e \u092e\u093e\u0924\u094d\u0930\u093e<\/strong>\u0909\u0924\u094d\u092a\u093e\u0926 \u0915\u0947 \u092a\u094d\u0930\u0915\u093e\u0930 \u0914\u0930 \u0915\u0941\u0932 \u0911\u0930\u094d\u0921\u0930 \u092e\u0942\u0932\u094d\u092f \u0915\u0947 \u0906\u0927\u093e\u0930 \u092a\u0930 \u0932\u091a\u0940\u0932\u093e\u092a\u0928\u0964<\/span><\/div>
\u0928\u092e\u0942\u0928\u0947<\/strong>\u091c\u092c \u092a\u0941\u0930\u094d\u091c\u093e \u0914\u0930 \u092a\u094d\u0930\u0915\u094d\u0930\u093f\u092f\u093e \u0909\u092a\u092f\u0941\u0915\u094d\u0924 \u0939\u094b\u0902, \u0924\u094b \u0928\u090f \u0917\u094d\u0930\u093e\u0939\u0915 1-5 \u092a\u0940\u0938 \u0915\u093e \u0905\u0928\u0941\u0930\u094b\u0927 \u0915\u0930 \u0938\u0915\u0924\u0947 \u0939\u0948\u0902\u0964<\/span><\/div>
\u092e\u093f\u0936\u094d\u0930\u093f\u0924 \u0911\u0930\u094d\u0921\u0930<\/strong>\u0935\u093f\u092d\u093f\u0928\u094d\u0928 \u092a\u094d\u0930\u0915\u093e\u0930 \u0915\u0947 \u0938\u0928 \u0917\u093f\u092f\u0930 \u092f\u093e \u0938\u0902\u092c\u0902\u0927\u093f\u0924 \u0917\u094d\u0930\u0939\u0940\u092f \u0918\u091f\u0915 \u092e\u0949\u0921\u0932\u094b\u0902 \u0915\u094b \u0924\u092c \u0938\u0902\u092f\u094b\u091c\u093f\u0924 \u0915\u093f\u092f\u093e \u091c\u093e \u0938\u0915\u0924\u093e \u0939\u0948 \u091c\u092c \u0915\u0941\u0932 \u0911\u0930\u094d\u0921\u0930 \u092e\u0942\u0932\u094d\u092f \u0932\u0917\u092d\u0917 1,500 \u0905\u092e\u0947\u0930\u093f\u0915\u0940 \u0921\u0949\u0932\u0930 \u092f\u093e \u0909\u0938\u0938\u0947 \u0905\u0927\u093f\u0915 \u0939\u094b\u0964<\/span><\/div>
\u091b\u094b\u091f\u0947 \u0911\u0930\u094d\u0921\u0930<\/strong>1-2 \u092a\u0940\u0938 \u0915\u0947 \u0911\u0930\u094d\u0921\u0930 \u092a\u0930 \u092c\u093e\u0924\u091a\u0940\u0924 \u0915\u0940 \u091c\u093e \u0938\u0915\u0924\u0940 \u0939\u0948, \u0906\u092e\u0924\u094c\u0930 \u092a\u0930 \u0907\u0928\u0915\u0940 \u092a\u094d\u0930\u0924\u093f \u092f\u0942\u0928\u093f\u091f \u0932\u093e\u0917\u0924 \u0905\u0927\u093f\u0915 \u0939\u094b\u0924\u0940 \u0939\u0948\u0964<\/span><\/div>
\u0935\u093f\u0924\u0930\u0923<\/strong>\u092e\u093e\u0928\u0915 \u092a\u0941\u0930\u094d\u091c\u0947: 10-25 \u0915\u093e\u0930\u094d\u092f\u0926\u093f\u0935\u0938\u0964 \u0905\u0928\u0941\u0915\u0942\u0932\u093f\u0924 \u092a\u0941\u0930\u094d\u091c\u0947: 20-45 \u0915\u093e\u0930\u094d\u092f\u0926\u093f\u0935\u0938\u0964 \u092a\u0930\u093f\u092f\u094b\u091c\u0928\u093e \u0909\u092a\u0915\u0930\u0923: 45-120 \u0915\u093e\u0930\u094d\u092f\u0926\u093f\u0935\u0938\u0964<\/span><\/div>
\u0935\u094d\u092f\u093e\u092a\u093e\u0930 \u0915\u0947 \u0928\u093f\u092f\u092e<\/strong>EXW, FOB, CIF \u0914\u0930 DAP \u0906\u092e\u0924\u094c\u0930 \u092a\u0930 \u092e\u093e\u0928\u094d\u092f \u0939\u0948\u0902\u0964 FCA, CFR, CPT, CIP \u0914\u0930 DDP \u092a\u0930 \u092e\u093e\u092e\u0932\u0947 \u0915\u0947 \u0905\u0928\u0941\u0938\u093e\u0930 \u091a\u0930\u094d\u091a\u093e \u0915\u0940 \u091c\u093e \u0938\u0915\u0924\u0940 \u0939\u0948\u0964<\/span><\/div><\/div><\/div>\n<\/div>\n<\/section>","protected":false},"excerpt":{"rendered":"

Runout only has meaning relative to the surface that defines the operating axis. On a sun gear, that datum may be a bore, spline, shaft or bearing seat.<\/p>","protected":false},"author":1,"featured_media":1094,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1075","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-sun-gears"],"_links":{"self":[{"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/posts\/1075","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/comments?post=1075"}],"version-history":[{"count":1,"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/posts\/1075\/revisions"}],"predecessor-version":[{"id":1121,"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/posts\/1075\/revisions\/1121"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/media\/1094"}],"wp:attachment":[{"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/media?parent=1075"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/categories?post=1075"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sun-gears.net\/hi\/wp-json\/wp\/v2\/tags?post=1075"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}