Abstract: In an embodiment, a mechanical seal includes: a bellows 10 sealing between a rotating-side seal ring 5 biased in the axial direction, and an outer periphery face of a rotational shaft 2; a case 11 fitted to the ring 5 and the outer periphery of the bellows 10; and a drive ring 12 tightening the bellows 10 to the shaft 2, wherein cutout grooves 5b running through in the axial direction are provided on the outer periphery area of the ring 5; detent cutout areas 5d are provided on the side face of the ring 5 on a sealing face S side in a manner extending in the circumferential direction from the cutout grooves 5b; and detent convex areas 11e are provided at the edge area of the case 11 on the ring 5 side in a manner facing the cutout grooves 5b and bulging in the inner-diameter direction.

Abstract: The present invention provides a mechanical seal preventing the deformation of the cartilage and exhibiting a good sealing performance. In said mechanical seal, the deformation of the back portion of the cartilage due to the force from the pump housing is absorbed by forming a groove portion having cross section substantially a triangular shape at the back portion of the cartilage. As a result, the deformation hardly transfers to the area near the inner tube portion of the cartilage 16 and the inner tube portion of the back portion; and the relative position of the seal ring, and the bellows or so scarcely changes with respect to the structure of the mating ring or so on the side of the rotation axis, thus the assembling length and the assembled load of the mechanical seal does not change, which allows the mechanical seal to exhibit good sealing performance.

Abstract: A primary technical goal of a mechanical seal device of the present invention is to decrease assembly cost thereof as well as machining cost thereof and to prevent wear of seal surfaces by preventing occurrence of squealing noises of the seal surfaces. The mechanical seal device comprises a first seal ring which is one of a pair of seal rings and disposes an engagement portion at the outer circumferential surface, a retainer ring which has a first support portion supporting an inner diameter surface of the first seal ring and a second support portion engaging the engagement portion and is fixed with either a seal housing or a shaft, and a gasket which joins the retainer ring and the first seal ring in a sealing manner, wherein an engagement clearance (C) formed in a rotational direction between the engagement portion and the second support portion is within 0.5 mm.

Abstract: The present invention provides a mechanical seal preventing the deformation of the cartilage and exhibiting a good sealing performance. In said mechanical seal, the deformation of the back portion 16d of the cartilage due to the force from the pump housing 3 is absorbed by forming a groove portion 16f having cross section substantially a triangular shape at the back portion 16d of the cartilage 16. As a result, the deformation hardly transfers to the area near the inner tube portion 16a of the cartilage 16 and the inner tube portion 16a of the back portion 16d; and the relative position of the seal ring 14, and the bellows 15 or so scarcely changes with respect to the structure of the mating ring 11 or so on the side of the rotation axis 2, thus the assembling length and the assembled load of the mechanical seal 9 does not change, which allows the mechanical seal 9 to exhibit good sealing performance.

Abstract: A primary technical goal of a mechanical seal device of the present invention is to decrease assembly cost thereof as well as machining cost thereof and to prevent wear of seal surfaces by preventing occurrence of squealing noises of the seal surfaces. The mechanical seal device comprises a first seal ring which is one of a pair of seal rings and disposes an engagement portion at the outer circumferential surface, a retainer ring which has a first support portion supporting an inner diameter surface of the first seal ring and a second support portion engaging the engagement portion and is fixed with either a seal housing or a shaft, and a gasket which joins the retainer ring and the first seal ring in a sealing manner, wherein an engagement clearance (C) formed in a rotational direction between the engagement portion and the second support portion is within 0.5 mm.

Abstract: A mechanical seal device for sealing a first seal sliding element and a second seal sliding element by bringing them into abutment, wherein the first seal sliding element is a seal sliding element having silicon carbide as a substrate and contains carbon and the second seal sliding element is a seal sliding element containing silicon carbide as its main ingredient and having 5 to 200 ?m size pores independently dispersed in it, and thereby excellent in durability and dry running wear resistance, preventing seizing or wear of the seal sliding element, and effectively suppressing occurrence of squeaking at the time of sliding.

Abstract: A primary technical goal of a mechanical seal device of the present invention is to decrease assembly cost thereof as well as machining cost thereof and to prevent wear of seal surfaces by preventing occurrence of squealing noises of the seal surfaces. The mechanical seal device comprises a first seal ring which is one of a pair of seal rings and disposes an engagement portion at the outer circumferential surface, a retainer ring which has a first support portion supporting an inner diameter surface of the first seal ring and a second support portion engaging the engagement portion and is fixed with either a seal housing or a shaft, and a gasket which joins the retainer ring and the first seal ring in a sealing manner, wherein an engagement clearance (C) formed in a rotational direction between the engagement portion and the second support portion is within 0.5 mm.