Shaft Collars
The Shaft Collars is a cylindrical mechanical part that’s positioned on the rotating shaft and can be an integral part of the sliding bearing.
Generally, the Shaft Collars and the bearing housing have an interference fit and a clearance match the shaft.
1, concept
A sleeve made of a complete cylindrical protective shaft is called a Shaft Collar.
The bearing shell is equivalent to the outer ring of the sliding bearing, the sleeve is integral and the opposite shaft is moving, while the bearing shell is segmented and the opposite shaft is rotating.
In the LEGOMindstorms series and BioTransRoSys series of robot components, the sleeves are particularly referred to as the silver-gray LEGO regular shaft holders, which are split into full sleeves and 1/2 sleeves.
The primary materials of all kinds of Shaft Collarss on the major hydropower generating units are ZQAl9-4, ZQSn10-1 and ZQSn6-6-3.
2, the difference
A Shaft Collars is a sleeve on a propeller shaft or a yoke shaft. Bearings (known as “shafts” in Japan) are parts that fix and decrease the coefficient of friction of the strain during mechanical transmission.
The Taper Pulleys similarity between the Shaft Collars and the 
bearing is that both bear the load of the shaft.
The difference between the two is that the sleeve is of integral structure, and the relative motion between the shaft and the sleeve is when rotating; and the bearing is usually split, and the rotation is the relative motion of the inner and outer rings of the bearing itself. But in essence, the Shaft Collars is truly a kind of sliding bearing.
3, common factors behind damage
During the long-term procedure of the Shaft Collars, the surface of the journal is put through the pressing pressure of the growth sleeve and the composite mechanical force, that may cause its permanent deformation, and the diameter may be reduced by 0.1mm~0.3mm. Consequently, the mechanical expansion and the effectiveness of the force are not up to the mandatory tightening power, and a coordinating gap occurs between your sleeve and the main shaft, causing put on of the sleeve.
4, the most recent repair method
Because of the large worth of components, the traditional repair methods are relatively expensive. With the advancement of advanced technology such as polymer composite materials overseas, some repair strategies with quick fix and low priced are favored. This method has also been released in China, and the older Fushun Blue 2211F components. The material gets the comprehensive mechanical properties, excellent adhesion and heat and corrosion level of resistance which cannot be compared with the traditional method. The maximum compressive power can reach 1200kg/cm2, and the adhesion (overlap shear tensile check) is definitely 225kg on the smooth steel surface area. /cm2. Therefore, it can be used for the fix of wear of large Shaft Collars parts. Moreover, the equipment doesn’t need to become disassembled in a huge level, which saves a whole lot of manpower and material resources for the business.