Labyrinth seals

The TSV series labyrinth seals are also suitable for higher peripheral speeds because they are non-contact. The round cord pressed between the labyrinth ring and the shaft ensures that the labyrinth ring does not slip despite the loose fit. The round cord made of fluorine rubber is suitable for temperatures up to +200 °C. The labyrinth seal allows the shaft to be misaligned by up to 0.5° on both sides. If necessary, the labyrinth can be relubricated. The simplest form of non-contact seal is the labyrinth seal, a narrow, smooth gap where the shaft passes through the housing. This type of seal is sufficient for sealing grease-lubricated bearing points in dry, dust-free rooms. The sealing effect of the gap can be increased if one or more concentric grooves are made in the through hole. The lubricating grease escaping through the gap is deposited in the grooves and prevents the ingress of contaminants. In the case of oil lubrication and horizontal shaft, helical grooves can be made in the through hole or on the shaft, which must be right-hand or left-hand depending on the direction of rotation of the shaft. These grooves return escaping oil to the bearing point. The prerequisite for this, however, is that the direction of rotation of the shaft does not change. Single or multi-threaded labyrinth seals have a significantly better sealing effect than simple gap seals, but they also require greater manufacturing effort. The sealing effect can be increased by occasionally pressing a water-insoluble lubricating grease, e.g. a lithium-calcium soap grease, through a lubricating channel into the labyrinth passages. The channels of the labyrinth seal can be arranged axially or radially, depending on the housing, self-retaining or non-self-retaining bearing design, mounting methods, space available, etc. The width of the axial channels in the labyrinth remains constant with axial displacement of the shaft in service unchanged and can therefore be very small. If the shaft is misaligned in relation to the housing during operation, labyrinths with bevelled labyrinth webs are used.