组合滚针轴承
 
　　FYB—组合滚针轴承是由向心滚针轴承和推力轴承部件组合的轴承单元，其结构紧凑 体积小，旋转精度高，可在承受很高径向负荷同时承受一定的轴向负荷。并且产品 结构形式多样、适应性广、易于安装。广泛用于机床、冶金机械、纺织机械和印刷 FYB—组合滚针轴承使用在配合轴设计为轴承滚道处，或配本公司专门生产的IR标准 圈进行镶套处理，其结构将更加紧凑。广泛用于机床、冶金机械、纺织机械和印刷 机械等各种机械设备，并可使机械系统设计的十分紧凑灵巧。

△结构形式
　　该类轴承有向心滚针与推力满装球、或与推力球、或与推力圆柱滚子、或与角接触球组合为一体，可承受单向或双向轴向载荷。也可根据用户特殊结构要求设计。

△产品精度
　　尺寸公差和几何精度按JB/T8877。
　　滚针直径相互差在2μm，精度等级为G2级（国标GB309）。
　　无内圈轴承装配前内切圆直径符合公差等级F6。
　　轴承径向游隙符合GB/T4604的0组规定值。
　　特殊精度等级按GB/T307.1。
　　对于轴承游隙、内切圆、精度等级特殊要求的详细情况应与本公司联系。

△材料
　　滚针材料为GCr15轴承钢，淬硬HRC60—65。
　　内外圈材料为GCr15轴承钢，淬硬HRC61—65。
　　保持架材料为优质低碳钢或增强尼龙。

△特殊说明
　　NKIA、NKIB系列轴承轴向载荷不得超过径向载荷的25%。
　　用于交变轴向载荷的支承场合必须对置安装。
　　推力轴承部件必须施加达轴向基本额定静载荷1%的预载荷。
　　使用塑料保持架时（后缀TN）连续工作不得超过运转温度+120°C。
　　推力轴承部件在轴承座中应自由活动。
　　轴承一般配置设计见滚动轴承应用技术中相关推荐。

△标准
　　GB/T6643—1996滚动轴承 滚针和推力圆柱滚子组合轴承 外形尺寸（GB-11）
　　JB/T3122—1991滚动轴承 滚针轴承和推力球组合轴承 外形尺寸（JB-1）
　　JB/T3123—1991滚动轴承 滚针轴承和角接触球组合轴承 外形尺寸（JB-1）
　　JB/T6644—1993滚动轴承 滚针和双向推力圆柱滚子组合轴承尺寸和公差（JB-3）
　　JB/T8877—2001滚动轴承 滚针组合轴承 技术条件（JB-12）
Combined Needle Roller Bearing

FYB---combined needle roller bearing is a bearing unit composed of radial needle roller bearing and thrust bearing parts. It features compact structure, small size and high rotating accuracy and bearing certain axial load while holding very high radial load, and multiple structure styles, broad adaptability and easy installation. It is widely used in lathe, metallurgical, textile and printing machinery.

FYB---combined needle roller bearing can be more compact in structure when it is used in auxiliary shafts designed as bearing raceway, or when it is inlayed with IR standard rings specially made by this company. This product can make the design of machine system highly compact and nimble.

Types of Designs:
This kind of bearing is a combination unit between radial needle rollers and full-component thrust balls, thrust cylindrical rollers or otherwise angular contact balls. It can bear one-way or two-way axial load. Special structure can be designed as well according to the requirements of customers.

Product Precision Accuracy:
Dimensional tolerance and geometrical accuracy is based on JB/T8877.
Mutual difference of needle roller diameter is 2μm, and the precision grade is G2 (ISO GB309).
The diameter of inscribed circle conforms to tolerance grade F6 before the fitting of outer ring with cage and roller assembly.

Bearing radial running clearance conforms to the value defined by 0 group of GB/T4604.
Special accuracy grade is based on GB/T307.1
For fuller information on the special requirements of bearing running clearance, inscribed circle and accuracy grade, please contact this company.

Materials:
Material for needle roller is GCr15 bearing steel, quench-hardening HRC60---65.
Material for inner and outer races is GCr15 bearing steel, quench-hardening HRC61---65.
Material for cages is quality low-carbon steel or reinforced nylon.

Special Directions:
Axial load of NKIA, NKIB series of bearings is not allowed to exceed radial load by 25%.
Being used for supporting alternative radial load, it must be installed in opposition.
Thrust bearing parts must exert preload up to 1% of axial basic rated static-load.
When plastic cages are used (suffixed with TN), operating temperature is not allowed to surpass +1200C during continuous work.

Thrust bearing parts can move freely in bearing bracket.
For general-disposition design of bearings, refer to the relevant recommendation in the applied technology of rolling bearings.