短语词组短语cabling pay -off 成缆放装置pay -off spool 放线盘rotating pay -off 旋转放线装置stationary pay -off 固定放线装置mobile pay -off 移动式放线装置drumpack pay -off 筒式放线装置stempack pay -off 圈式放线装置;捆式放线装置payoff function 支付函数 返回 pay off