1.1 This specification covers mechanical end-face seals for centrifugal and positive displacement pumps for shipboard use. 1.2 The following types of seals are not included in this specification: lip seals, oil seals, cir This specification covers mechanical end-face seals for centrifugal and positive displacement pumps for shipboard use. Mechanical seals shall be classified by type, grade, and class. Types: type A - inside single mounted seals, type B - outside single