A Seminar on Mechanical Seal By Mr.Kusekar S.K. Under the guidance of Dr.Pawar M.S.(Principal)

Mechanical Seal Failure Modes and Cause EventsA mechanical seal may fail during its service by wear, corrosion, fracture, and so on. In a plant, leakage from a machine or machine components is reported as a failure mode or symptom. A cause event that singly or in combination with other cause events leads to various failure modes or a general failure mode, includes, design-related, process-related, and operation- and maintenance-related cause events.The list of cause events is prepared after consultation with design and practicing engineers. Some of these cause events will directly influence the failure mode of a mechanical seal, whereas, the others will be influenced by a stage relation 1Cause Event

1. Direct Cause Event1. A problem of abrasive contaminants,2. Improper seal material, 3.Problem of maintaining pressure velocity coefficient (PV value),4. Excessive fluid pressure,5. Improper seal design, 6.Insufficient seal lubrication, excessive seal face temperature,7. Failure of secondary seal,lead to seal failure directly. For example, excessive seal face temperature leads to high heat generation causing seal failure. Similarly insufficient seal lubrication leads to seal failure because inadequate lubrication causes high heat generation in the seal, which leads to seal failure. These cause events are called direct cause

2 2. Indirect Cause Event1.problem of misalignment, 2.improper seal assembly,3. installation and4. poor maintenance practices are called indirect cause events. For example, poor maintenance practices such as inadequate cooling lead to an increase in the seal face temperature, which further causes seal failure..

3MECHANICAL SEAL DESIGN WITH SUPERIOR THERMAL CHARACTERISTIC

Heat Transfer Consideration in Mechanical SealsH= P VA f

4Thermal Effects on Seal Performance and Behavior Thermally Induced Radial Taper Thermally Induced Waviness Heat Checking and Hot Spotting Blistering of Carbon

# Effects on Process Fluid Heat Exchangers, Surface Treatments and Coatings

5Mechanical Seal Application

Mechanical seals are used to prevent leakages in pumpCompressorMechanical shaft seal.Any failure of mechanical seal hazardus to the system.

6Conclusion

A mechanical face seal is an important component of variety of pumps used in chemical,petrochemical and process industry. The primary function of a mechanical seal is to prevent leakage of the process fluid from the pump housing and shaft to the environment.The factors that affect the performance of a mechanical seal to leak are friction, wear and its thermal characteristics. Improving upon the thermal characteristics of a mating ring in a mechanical seal would enhance its performance. Implanting a heat exchanger in the mating ring hold great promise for improving the performance of mechanical seals from the viewpoint of reducing heat at the interface and hence enhance the performance of the mechanical seal.

7Mechanical seals are used to prevent leakages in pump,compressor,mechanical shaft seal.Any failureofmechanical seal hazardous to the system

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