MECHANICAL SEAL

PURPOSE:To enable a mechanical seal for a pump or the like to be easily removably attached by providing a rotation stopping ring between a stopping ring and an annular body with first and second catching portions which engage respectively catching portions of the annular body and a housing. CONSTITUTION:In the assemblage of a mechanical seal, first a rotor 37 incorporating integrally a rotary seal ring 25, a seal ring 26, a spring 27 and a rotary transmitting portion 28 is inserted into a rotary shaft 15 to mount a fixed seal ring 22 on a housing 21. Next, an annular body 23 is inserted and a rotation stopping ring 32 is adapted to bear against the annular body 23 while a second catching portion 35 is put into a catching hole 36 in the housing 21 and a jig is inserted into holes 38, 39 in a stopping ring 31 to move the holes close to each other for reducing the diameter of the ring 31 while press inserting the ring until it fits in a groove 30 of the housing 21. Thus, the annular body 23 is caught by the housing 21 at the second catching portion 35, of the rotation stopping ring 32 and by a catching hole 33 of the annular body 23 at the first catching portion 34 to limit the rotation of the annular body. This assemblage can be easily carried out all from the same spot in the axial direction and the disassembly also easily carried out in the reverse order.