Heat load of mechanical seal face material damage |
09-10 |
In one or two end face appeared gap, this phenomenon shows that the two face is too big, apart when two ends together tightly, can produce a gap. The common cause of end face separation is flashing import mechanical seal medium. For example, water, especially in the hot water system or contain the condensate liquid, water evaporation, and separated the two ends. Pump cavitation and seal block also may cause the cause of the gap is to make the container security seals. In this case, it is not caused by vibration and coupling the champions league, because it is not enough to make face generation gap. The lower end face temperature is a common way to prevent damage of medium evaporation end sharply. At the same time, USES the materials with good thermal conductivity is also good, such as with nickel-based carbide and leaching of copper and graphite group, in addition, the balance type mechanical cable tie wraps, or the use of special corrosion resistant mechanical seal gland from external injection liquid cooling, or directly to the cooling chamber seal, and so on, is very effective to reduce the temperature of the seal face. Failure of mechanical seal, friction pair end surface radial cracks are very fine, radial cracks and blisters or mark, or even cracked. This is caused by sealing overheating, especially ceramic, carbide seal face prone to this type of injury. Poor lubricity of medium, high overload, high operating temperature, velocity, improper matching material combination, etc., including any kind of factor, or is the superposition of several factors, can produce excessive friction heat, if frictional heat can't send out in time, will generate dyeing mechanical seal of hot crack, resulting in excessive wear and high leakage. Solve the overheating of the seal, in addition to change the face area, reduce the load, also can use static type Fixed Length plastic seal and diversion of forced cooling circulating fluid sealing surface, or on the seal face hydrodynamic trough to be solved. Friction on the face, there are many tiny hot spots and discolouration of the isolation zone, suggesting that seals under high pressure and thermal distortion under the influence of deformation. For the thermal deformation of the face, the general method of calculation is not allowed, should use the finite element method to calculate, in order to improve the design of the sealing ring.