Redesign and Fabrication of a Mechanical Seal for Pumps

For this project, the main objective is to redesign a new mechanical seal that will last longer and reduce the possibility of leak. The redesign process is based on the previous case histories and the “sequence-of-events” records, which categorize the possible root causes for the mechanical seal failure. The problems for this mechanical that has been identified from “sequence-of-events” are it generates excessive heat at the mating face; leak and its design do not follow the standard of American Petroleum Institute 682. The excessive heat will lead to the leak of the pump when the heat melts the o-ring. Beside that, excessive heat will vaporize the sealing fluid. The bubble produced, will reduce the efficiency of the pump. The solution for excessive heat is by redesigning the rotary face. To reduce the effect of back pressure subjected on the rotary face, proper balance ratio be used as a basis to design this rotary face. For API standard, the seal face has been changed to the solid seal face instead of inserted seal face. Beside that, the deflection of the shaft is reduced by simplified the design and reduce the weight of parts that subjected on the shaft. The main outcome of the project is the fabrication of a new mechanical seal which has been tested under a pressure test based on API 682 standard. Consequently, all the design requirements been met successfully.