Assembly of Seeger Retaining Rings
Seeger retaining systems can only fulfill their function if they are assembled perfectly. During assembly, the ring is mostly subjected to higher stresses than during later operation. Improper assembly damages the ring and/or the groove.
Axially-mountable Seeger-Rings
These rings are equipped with assembly holes and are mostly fitted and dismantled using special pliers. It is important to use the plier suitable for each single ring. This is given for each ring size in the data charts; a list of the pliers is given on pages 109 110. Elastic deformation of Seeger rings during assembly leads to very high bending stresses and so the following always applies:
"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 stainless steel. Overstressing during assembly leads to plastic deformations with the result that rings fit loosely or without adequate prestress in the groove. Extreme overstressing of bore rings is not possible because these can only be expanded up to contact of the ring ends. Nevertheless, bore rings should only be closed just enough to allow insertion into the bore. On shaft rings, however, there is always a risk of overexpansion because they have no limit. Assembly tools with 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 assembly using tapers (Figure 14).
Since circlips are not equipped with assembly holes, it is best to assemble them using tapers. Circlips with pointed ends for shafts (type SW up to 38 mm nominal diameter) can also be assembled using circlips pliers and, to some extent, can also be dismantled with them. Dismantling circlips, however, poses great 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 fitted 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 and Seeger triangular retainers must be assembled using special bushes or drifts. Please contact our technical advisory service.
Radially-mountable Seeger-Rings
The main advantage of radially-mountable Seeger rings is that they are easily assembled. These Seeger rings types RA and H are assembled simply, and without the need for a special tool, by pressing them into the shaft groove. It is recommended to use Seeger ring dispensers (see Page 111) to further shorten assembly times. These are available for Seeger retaining rings to DIN 6799 in dimensions of 1,2 to 12 mm and Seeger crescent rings in dimensions of 3 to 28 mm. For use in Seeger ring dispensers, the rings can be supplied in magazines. For this purpose, the Seeger retaining rings and Seeger crescent rings are held together by a rail or adhesive tape. They are removed from the dispenser using an applicator which simultaneously service to force them into the groove. Angled applicators are also available for assembly in poorly accessible locations.
Delivery of Seeger-Rings
Since open retaining rings tend to hook together when supplied in boxes or bags, making removal very time-consuming, it is recommended to order stacked deliveries. Our technical advisory service will be pleased to answer further inquires.