三排滾柱式回轉支承有三個座圈，上下及徑向滾道路各自分開，使得每一排滾柱的負載都能確切地加以確定。能夠同時承受各種載荷，是四種產品中承載能力ZD的一種，軸、徑向尺寸都較大，結構牢固，特別適用于要求較大直徑的重型機械，如斗輪式挖掘機、輪式起重機、船用起重機、港口起重機，鋼水運轉臺及大噸位汽車起重機等機械上。

The three-row roller slewing bearing has three seat-rings,which separate the upper,lower and radial races,via which the load of each row of the rollers may be specified.It may bear different loads simultaneously and its load capacity is the largest one among the four models.

Thanks to the large size of its axle and radius,it is sturdy and especially suitable for heavy-duty machines which require large working radius.such as bucket-wheel excavators,wheeled cranes,ship cranes,ladle turrets,heavyduty mobile cranes etc.