Nafi Sayer is a type of mechanical seal that is used to prevent the leakage of fluids and gases from the water pump or electric motor housing. This seal has two fixed and moving parts that face pressure and friction and make the fluid inside the chamber unable to leak out. Other umbilicals have different types depending on the type of pump, fluid, pressure, temperature and operating conditions. Some of the common types of umbilical cords are: ceramic, silicon, coal, steel, etc.