{"id":901,"date":"2026-09-10T04:01:54","date_gmt":"2026-09-10T04:01:54","guid":{"rendered":"https:\/\/nm-coupling.net\/technical-guides\/bore-keyway-guide\/"},"modified":"2026-09-10T06:14:01","modified_gmt":"2026-09-10T06:14:01","slug":"bore-keyway-guide","status":"publish","type":"page","link":"https:\/\/nm-coupling.net\/fa\/technical-guides\/bore-keyway-guide\/","title":{"rendered":"NM Coupling Bore & Keyway RFQ Guide"},"content":{"rendered":"

The model number tells us the coupling size. It does not tell us your finished bores. Those come from the shafts the coupling will connect, and the two sides can be different.<\/p>\n

Write the driving and driven sides separately.<\/h2>\n

A useful line item reads like this: model, driving shaft diameter and keyway, driven shaft diameter and keyway, quantity. Add tolerance or fit requirements when they are controlled by your drawing. If one side uses an inch shaft and the other is metric, keep each dimension in its original unit and provide the drawing where possible.<\/p>\n

Check d max before asking for a large bore.<\/h2>\n

Every NM model has a specified maximum bore. Staying below that number is necessary, but it is not the only design check: hub section, keyway, material and duty still matter. A requested bore at the very top of the range should be reviewed with the actual keyway and torque requirement rather than accepted as a geometry-only decision.<\/p>\n

\n
<\/span><\/p>\n

Driving side<\/h3>\n

Shaft diameter, keyway and any fit\/tolerance requirement.<\/p>\n<\/div>\n

<\/span><\/p>\n

Driven side<\/h3>\n

Specify independently; do not write \u201csame\u201d unless it really is.<\/p>\n<\/div>\n

<\/span><\/p>\n

Maximum bore<\/h3>\n

Compare both shafts with d max for the chosen model.<\/p>\n<\/div>\n

<\/span><\/p>\n

Drawing control<\/h3>\n

Attach the machine drawing when tolerances, shoulders or unusual keys matter.<\/p>\n<\/div>\n<\/div>","protected":false},"excerpt":{"rendered":"

Describe both shafts separately and keep finished-bore requirements within each model\u2019s specified d max.<\/p>","protected":false},"author":1,"featured_media":0,"parent":860,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-901","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/pages\/901","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/comments?post=901"}],"version-history":[{"count":1,"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/pages\/901\/revisions"}],"predecessor-version":[{"id":956,"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/pages\/901\/revisions\/956"}],"up":[{"embeddable":true,"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/pages\/860"}],"wp:attachment":[{"href":"https:\/\/nm-coupling.net\/fa\/wp-json\/wp\/v2\/media?parent=901"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}