Pumps, centrifugal chemical pump, sealing

Sealing the Centrifugal Chemical Pump Although detailed treatment of shaft seals is presented in the subsection Sealing of... 

The most common maintenance problem with centrifugal pumps is with the seals. Mechanical seal problems account for most of the pump repairs in a chemical plant, with bearing failures a distant second. The absence of an external motor (on canned pumps) and a seal is appeahng to those experienced with mechanical seal pumps. 

Figure 3-1A. Sealless Magnetic Drive Centrifugal Pump, no seals, no leakage, no coupling. Chemical resistance depends on materials of construction. See Table 3-2. (By permission, LaBour Pump Co.)...

A wide variety of excellent pumps is available in the chemical industry. It is sometimes a problem to choose the best from the large number available. This discussion will be limited to centrifugal pumps. Assuming that one has sized the pump, decided on a centrifugal pump, and chosen a suitable list of vendors, the main choices involve (1) metallurgy, (2) seal-less pumps versus conventional centrifugal pumps, and (3) the type of seals for conventional pumps. 

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