Cartridge seal stack

A rotary cartridge seal stack assembly comprising:

• a plurality of rotary cartridge seals disposed in and abutting relationship between a housing bore and a shaft, each rotary cartridge real comprising:
• a cold flowable plastic ring having body means for sealably engaging a housing bore and lip means for sealably engaging a shaft rotating within said housing bore;
• separable metal retainer means for fixing said plastic ring within said housing bore and around said shaft, said separable metal retainer means having a surface of revolution with a rear portion having a diameter suitable for press fitting into said housing bore and a front portion of lesser diameter ending in a ring;
• and
• means defining an internal groove in said body means for engaging the ring therein in order to latch the plastic ring and metal retainer means together with residual stress in an axial direction within the plastic ring due to the groove and ring dimensions and shape, said internal groove having a diameter greater than the ring and wherein a width of said internal groove is smaller than a width of the ring in order to maintain axial stress in the plastic ring.

A rotary cartridge seal stack assembly compressing:

• a plurality of rotary cartridge seals disposed in an abutting relationship between a housing bore and a shaft, each rotary cartridge real comprising:
• a cold flowable plastic ring having body means for sealably engaging a housing bore and lip means for sealably engaging a shaft rotating within said housing bore;
• spring means, disposed between the body means and the lip means, for biasing said lip means against the shaft;
• separable metal retainer means for fixing said plastic ring and spring within said housing bore and around said shaft, said separable metal retainer means having a surface of revolution with a rear portion having a radius suitable for press fitting into said housing bore and a front portion of lesser radius ending in a ring, said rear portion and ring being connected by a thin spring portion;
• and
• means defining an internal groove in said body means for engaging the ring therein in order to latch the plastic ring and metal retainer means together with residual stress in a radial direction within the plastic ring due to biasing action by the retainer means spring portion.

A rotary cartridge seal stack assembly comprising:

• a plurality of rotary cartridge seals disposed in an abutting relationship between a housing bore and a shaft, each rotary cartridge real comprising:
• a cold flowable plastic ring having body means for sealably engaging a housing bore and lip means for sealably engaging a shaft rotating within said housing bore;
• spring means, disposed between the body means and the lip means, for biasing said lip means against the shaft;
• separable metal retainer means for fixing said plastic ring within said housing bore and around said shaft, said separable metal retainer means having a surface of revolution with a rear portion having a radius suitable for press fitting into said housing bore and a front portion of lesser radius ending in a ring;
• means defining an internal groove in said body means for engaging the ring therein in order to latch the plastic ring and metal retainer means together;
• and
• spring portion means, connecting the retainer rear portion and ring, for controlling residual stress in a radial direction within the plastic ring and preventing shrinkage of the plastic ring toward the shaft.