軸承（Bearing）是當(dang)代機械設備(bei)中一種重(zhong)要零部件。它的主(zhu)要功能是支撐機械旋轉體，降低其(qi)運動過(guo)程(cheng)中的摩擦系(xi)數，并保證其(qi)回轉精度。

    按運(yun)動元(yuan)件摩擦性質的(de)不同，軸(zhou)(zhou)承(cheng)可分為滾動軸(zhou)(zhou)承(cheng)和滑動軸(zhou)(zhou)承(cheng)兩大(da)類。其(qi)中滾動軸(zhou)(zhou)承(cheng)已經標準(zhun)化、系列化，但與滑動軸(zhou)(zhou)承(cheng)相(xiang)比它的(de)徑向尺(chi)寸、振動和噪聲(sheng)較大(da)，價格也較高。

    滾動軸(zhou)承一般(ban)由外圈(quan)、內圈(quan)、滾動體和(he)保持架四部分組(zu)成(cheng)。按滾動體的形狀，滾動軸(zhou)承分為球軸(zhou)承和(he)滾子軸(zhou)承兩大類。

    早期的直線運(yun)(yun)動(dong)(dong)軸(zhou)承(cheng)(cheng)形(xing)式(shi)，就(jiu)是在一(yi)排撬板下放置一(yi)排木桿(gan)。現代(dai)(dai)直線運(yun)(yun)動(dong)(dong)軸(zhou)承(cheng)(cheng)使用的是同一(yi)種(zhong)工作原理，只(zhi)(zhi)不過有時用球代(dai)(dai)替滾(gun)(gun)子(zi)(zi)。最(zui)簡單(dan)的旋(xuan)轉軸(zhou)承(cheng)(cheng)是軸(zhou)套軸(zhou)承(cheng)(cheng)，它只(zhi)(zhi)是一(yi)個(ge)夾在車(che)輪和輪軸(zhou)之間的襯套。這種(zhong)設(she)計隨(sui)后被滾(gun)(gun)動(dong)(dong)軸(zhou)承(cheng)(cheng)替代(dai)(dai)，就(jiu)是用很多圓柱形(xing)的滾(gun)(gun)子(zi)(zi)替代(dai)(dai)原先(xian)的襯套，每(mei)個(ge)滾(gun)(gun)動(dong)(dong)體就(jiu)像一(yi)個(ge)單(dan)獨的車(che)輪。

    調心滾子軸承有(you)兩(liang)列對稱型球面滾子(zi)，主(zhu)要承(cheng)(cheng)(cheng)(cheng)(cheng)受(shou)(shou)(shou)徑(jing)向(xiang)載(zai)荷(he)，同(tong)時也能(neng)(neng)(neng)(neng)承(cheng)(cheng)(cheng)(cheng)(cheng)受(shou)(shou)(shou)任一方向(xiang)的軸(zhou)向(xiang)載(zai)荷(he)，但(dan)不能(neng)(neng)(neng)(neng)承(cheng)(cheng)(cheng)(cheng)(cheng)受(shou)(shou)(shou)純軸(zhou)向(xiang)載(zai)荷(he)。該類軸(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)外圈滾道是球面形(xing)，故其(qi)調心(xin)性能(neng)(neng)(neng)(neng)良好，能(neng)(neng)(neng)(neng)補償同(tong)軸(zhou)度誤(wu)差，當(dang)軸(zhou)受(shou)(shou)(shou)力(li)(li)彎曲或安裝不同(tong)心(xin)時軸(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)仍可正常使用(yong)，調心(xin)性隨軸(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)尺寸系(xi)列不同(tong)而異，一般(ban)所(suo)允(yun)許的調心(xin)角度為1~2.5度 ，該類型軸(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)的負(fu)荷(he)能(neng)(neng)(neng)(neng)力(li)(li)較(jiao)大(da)，除能(neng)(neng)(neng)(neng)承(cheng)(cheng)(cheng)(cheng)(cheng)受(shou)(shou)(shou)徑(jing)向(xiang)負(fu)荷(he)外軸(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)還能(neng)(neng)(neng)(neng)承(cheng)(cheng)(cheng)(cheng)(cheng)受(shou)(shou)(shou)雙(shuang)向(xiang)作用(yong)的軸(zhou)向(xiang)負(fu)荷(he)，具有(you)較(jiao)好的抗(kang)沖擊能(neng)(neng)(neng)(neng)力(li)(li)，一般(ban)來說調心(xin)滾子(zi)軸(zhou)承(cheng)(cheng)(cheng)(cheng)(cheng)所(suo)允(yun)許的工作轉速較(jiao)低。適用(yong)于重載(zai)或振動載(zai)荷(he)下工作。