Assembly of Rings
SEEGER® retaining systems can only fulfill their function if they are assembled correctly. During assembly, the ring is subjected to higher stresses than when it is in operation. Improper assembly damages the ring and/or the groove.
These rings are equipped with assembly holes and are typically fitted and dismantled using special pliers. It is important to use the appropriate pliers as designed for each single ring. Please refer to the pliers data chart for the correct pliers/ring combination. If rings are over-expanded, elastic deformation of SEEGER® rings can occur during assembly. This leads to very high bending stresses, so it is important to note:
During assembly, a SEEGER® ring should be expanded or closed only to the extent necessary to pass over the shaft or into the bore. The shaft and bore must be of the same nominal diameter as the ring.
This rule applies particularly to rings made of materials with lower elastic yield, such as bronze and corrosion-resistant stainless steel. Overstressing during assembly leads to plastic deformation of the ring; resulting in a ring that fits loosely or without adequate pre-load in the groove. Bore rings should only be closed (ring ends touching each other) just enough to allow insertion into the bore.
Special attention should be paid to shaft rings, as there is always a risk of overexpansion because they have no physical limit. Assembly tools with “stops” or limits should therefore be used to avoid overexpansion. Since the rigid grip rings are particularly endangered by overexpansion, the appropriate pliers are equipped with limiting screws.
The most reliable protection against overexpansion is an assembly using tapered mandrels.
Figure 4.1: Taper Assembly in Bore
Figure 4.2: Taper Assembly on Shaft
Since SEEGER® snap rings (circlips) are not equipped with assembly holes, it is best to assemble those using tapered mandrels. Snap rings with pointed ends for shafts (type SW up to 38 mm nominal diameter) can be assembled using circlips pliers and, to some extent, can also be dismantled with them. Dismantling snap rings, however, poses special problems, particularly in the case of smaller and relatively rigid rings. Special tools are not available and the rings must be levered out of the groove.
SEEGER® L-rings and SEEGER® W-rings must be assembled on the shaft, or inserted in the bore, using pliers and then pressed on with a bush or drift until they snap into the groove. SEEGER® circular self-locking rings for shafts or bores must be assembled using special bushes or drifts.
Radially-mountable Seeger-Rings (Retaining Rings)
The main advantage of radially-mounted Seeger-Rings (retaining rings) is that they are easy to be assembled. These Seeger-Rings, types RA and H, are assembled without the need for a special tool, by pressing them into the shaft groove.
Delivery of Seeger-Rings
Since open-ended retaining rings tend to hook together or get tangled when supplied loosely in boxes or bags, it makes removal and use very time-consuming. Seeger can provide rings in shrink wrapped stacks, which eliminates excess handling, facilitates automated assembly and virtually eliminates the potential of mixed material. It is recommended to order this stacked packaging for most assembly operations. Our technical advisory service will be pleased to answer further inquiries.
For questions about the assembly of Seeger-Rings, please dial +49 6174 205-0 and ask for a representative in our Engineering Department.