Special PTFE compounds with excellent resistance to wear and a good sealing action have specially developed for oil seals with PTFE sealing lips. .PTFE sealing lips are PTFE compound discs that are mechanically formed to a diameter slightly smaller than the shaft. The forming of the lip creats a shape that takes advantage of the hoop strength of the PTFE compound discs. This hoop strength provides the load that is critical for low or no pressure applications to obtain a positive seal.The sealing element typically has a smooth surface contacting the shaft. For applications sealing liquid at below 0.1Mpa, a hydrodynamic spiral feature can be machined into the surface of the sealing element to provide a positive pumping action to drive fluid away from the air side of the seal.It is critical to match the seal to the shaft rotation to ensure positive sealing. Sealing element Material Selection: LP1001 Premium grade virgin PTFE for static, slow-dynamic or light-duty application. Also for food-contact service requiring FDA approval. Color:white LP2030 Highly wear resistant in fast-rotary service and on hardened shafts in well-lubricated rotary service, Color:Dark grey LP8030 Good wear resistant in fast-rotary applications. Less abrasive to soft shaft and in poorly-lubricated service. LP3020 Low coeffication of friction and excellent wear resistance combined with low surface pressure. Color: black