Frederic W Buse Stephen A Jaskiewicz

Sealless pumps are developed to eliminate the liquid leakage to the atmosphere that occurs from pumps that employ packing or mechanical seals. This leakage is usually toxic or dangerous to the environment. Sometimes the leakage is valuable. Eighty percent of the applications are for pressures below 200 lb/in2 (13.8 bar) and below 250°F (120°C).

Sealless pumps are divided into two categories: magnetic drive pumps and canned motor pumps. The two categories compete against themselves in certain applications, but for the most part they each have their own market niche into which they are applied. Both have encapsulated inner driven mechanisms. On a magnetic drive pump (see Figure 5 in Section 2.2.7.1), the impeller is mounted to an inner magnet carrier. The inner and outer magnetic carriers are sealed by what is called a shell, which contains pump internal pressure. On a canned motor pump (see Figure 1 in Section 2.2.7.2), the impeller is mounted directly to the motor rotor. The atmospheric sealing element between the motor stator and rotor is called a liner or "can." Both magnetic drive and canned motor pumps use product lubricated bearings of compatible design and materials. These bearings are usually cooled and lubricated by the pump liquid.

The following sections describe both magnetic drive and canned motor pumps.

End of Days Apocalypse

End of Days Apocalypse

This work on 2012 will attempt to note them allfrom the concepts andinvolvement by the authors of the Bible and its interpreters and theprophecies depicted in both the Hopi petroglyphs and the Mayan calendarto the prophetic uttering of such psychics, mediums, and prophets asNostradamus, Madame Blavatsky, Edgar Cayce, and Jean Dixon.

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