13 - Mechanical seals

Abstract

This chapter deals with the history and development of mechanical seals—a device that forms a barrier between rotary and stationary parts in pumps. This chapter also studies the type of mechanical seals such as the single, unbalanced, inside-mounted mechanical seal; the single, outside-mounted, unbalanced seal; the single, balanced, internal mechanical seal; and the single, balanced, external mechanical seal. The mechanical seal manufactures develop O-rings as secondary seals. The list of advantages of O-rings and balanced seal is also listed in this chapter. The concept of balance seal is explained mathematically. The chapter further discusses the cartridge mechanical seal that has all the rotary and stationary parts as one integral unit along with its advantages. This chapter also explains the double seals, the tandem dual seal, the back-to-back double seal, and face-to-face dual seal. The support system for dual seals namely the thermal convection tank, the turbo tank, and the pumping tank is explained in this chapter. Overall, this chapter explains the mechanical seals, its development, and types of mechanical seals with its advantages.