If matched pairs of tapered roller bearings arranged face-to-face or back-to-back are mounted together with a third bearing, the bearing arrangement is statically indeterminate.

如果面对面或背对背配置的相配圆锥滚子轴承对与第三个轴承安装在一起，轴承配置为静态不确定。

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Double row angular contact ball bearings are a form of back-to-back pairs of single row angular contact ball bearings, which support axial load in both directions as well as support radial load.

单列角接触轴承背对背的配对形式，可承受两个方向的轴向载荷，同时可承受径向载荷。

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NKE spindle bearings of universal design (suffix UL) feature a light preload when mounted in pairs or sets either face to face or back to back.

NKE的通用设计(后缀ul)，主轴轴承具有轻预紧安装时成对或成套面对面或背靠背。

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Jeanswear producer Levi Strauss, which raised prices earlier this year to cover higher cotton costs, said earlier this week it ended up slashing prices at retail this fall in order to move merchandise as families bought fewer pairs of back-to-school jeans rather than spend more.

FORBES: Cotton's Pinch on Clothing Stores Continues

Most pairs make it back to the barn for minor surgery: new ankle padding, a sole or an eyelet.

FORBES: Entrepreneurs

Bling Nation is looking to change that with its service, which pairs RFID-enabled stickers with a back-end system that charges purchases to credit cards (via PayPal) and sends text-message receipts to cellphones.

FORBES: Bling Nation Prepares National Rollout Of Mobile Payments, Handset Partnerships