The GAMMA Seal is the result of a large-scale development project covering many years of attempts to combine the capability of conventional mechanical seals to operate at high speeds with the simplicity of the Rotary Shaft Lip Seal. Figure 92 shows the different types, which are characterized by simple design. The basic design consists of two parts, a sealing element and metal case. The GAMMA Seal is designed to be fixed to the shaft at a pre-determined distance from the a sealing surface, which is positioned perpendicularly to the shaft, for example, the end wall of a bearing housing. During rotation, the sealing lip rubs against the counterface under a contact pressure calculated to achieve a sealing function. The seal also operates as a deflector ring, and its centrifugal action improves sealing. Due to the effect of centrifugal force, the sealing lip tends to reduce its contact pressure with increasing speed. As a result, the curve for power loss is very favorable (see Figure 86). At a peripheral speed of around 12 m/s, friction losses begin to diminish and cease completely at about 20 m/s, when the sealing lip has completely lifted free of counterfaces. The GAMMA Seal then functions as a combined deflector ring and clearance seal. The GAMMA Seal is primarily intended for sealing against foreign matter, liquid splatter and grease.