The phenomenon of wear marks in the sealing contact area of u200bu200brolling bearings: the sealing lip contact area on the rib has a groove in the circumferential direction, which is often bright. Because of the infiltration of dirt, there are often wear and tear of the sealing lip and damage to the bearing. In some cases, corrosion in the sealing area can be found, see Figure 87. Reason: Excessive external contaminants, especially in humid environments. Dry lips work. Remedy: Increase the seal, such as a flinger. Lubricate the sealing lip. Discoloration of the seal contact area: brown or blue in the seal lip contact area, especially in the case of shaft seals. Overheating causes hardening and excessive wear of the seal, see section 3.6.1. Reason: The contact area between the lip and the shaft is overheated due to interference or high seal press-in force. There is insufficient lubrication in the contact area of u200bu200bthe sealing lip. Remedy: Lubricate the sealing lip and reduce the sealing pressure within the allowable range of the sealing effect.