A mechanical seal in which a rotary ring can be more reliably positioned. A rotary ring unit 100 includes: a sleeve 120 fixed to a rotary shaft 500; and a rotary ring 110 of which a movement in an axial direction and a rotation with respect to the sleeve 120 is restricted, a fixed ring unit 200 includes: a fixed ring 210 configured to slide on an end surface of the rotary ring 110; and a bellows 250 which presses the fixed ring 210 toward the rotary ring 110, and the sleeve 120 is provided with a stopper 140 which restricts a movement of the rotary ring 110 toward the fixed ring 210.

The purpose of the present invention is to provide a mechanical seal in which a stationary-side sealing ring can follow the movement of a rotating-side sealing ring to provide reliable sealing properties and by which the entire device can be made compact. A mechanical seal in which a rotating-side sealing ring 13 attached to a shaft 2 and a stationary-side sealing ring 21 attached to a housing 3 slide relative to each other and seal between the housing 3 and the shaft 2 includes a case 22 which is attached to the housing 3 and which contains the stationary-side sealing ring 21, and a seal member 23 which is disposed between the case 22 and the stationary-side sealing ring 21, and the case 22 includes a holding part 22d which regulates the seal member 23 from moving to both sides in the axial direction thereof.

A mechanical seal includes: a mating ring; a seal ring; a casing which includes a pop-out regulation portion supporting the seal ring not to be rotatable and to be axially movable and coming into contact with the seal ring to regulate the seal ring from popping out toward the mating ring; an urging member disposed between the seal ring and a back wall of the casing axially overlapping with the seal ring and axially urges the seal ring toward the mating ring; and an annular secondary seal sealing a gap between the casing and the seal ring. The casing includes a regulation wall which regulates the secondary seal from moving toward the side opposite to the mating ring and an axial dimension between the seal ring and the regulation wall is equal to or less than a half of an axial dimension of the secondary seal while the seal ring and the pop-out regulation portion are in contact with each other.

A seal assembly includes a housing at least partially defining a seal opening and at least partially surrounding a rotatable shaft. A carbon seal is located at least partially in the seal opening and includes a sealing surface. The rotatable shaft includes a radially facing surface that has a carbide based coating and a diamond-like carbon coating in engagement with the sealing surface on the carbon seal.

A non-collapsible flexible sealing membrane (or bellows) for incorporation in a mechanical seal assembly and use in rotary shaft equipment. The sealing membrane includes a substantially radially outward extending first flange portion, which can be urged into an axially shiftable ring by a biasing mechanism. The sealing membrane further includes a substantially axially outboard extending second coaxial portion, substantially radially inward of the balance diameter of the seal. The horizontal portion is advantageously held fixed to a stub sleeve by an annular band. The angle between the vertical portion and the horizontal portion of sealing membrane enables directional control of the forces acting on stub sleeve and primary ring.

A seal assembly for a rotatable shaft assembly includes a seal housing and each of a main seal and a dust seal extending circumferentially around a seal housing center axis. The dust seal includes a radially inward dust seal lip, and is formed by a sealing layer having a plurality of ventilation openings formed therein, and a debris-blocking filter layer attached to the sealing layer and positioned across the ventilation openings. The main seal and dust seal assist in maintaining lubricating oil within a seal cavity. The dust seal prevents entry of debris whilst ventilating the seal cavity to limit carbonization of oil on seal assembly components. In an implementation the seal assembly is part of a rotatable crankshaft assembly.

A mechanical seal includes a pair of seal rings that rotate relative to each other; and a retainer that holds the seal ring. The retainer includes an annular base portion, an annular holding portion that is externally fitted to an outer periphery of the seal ring, and an annular connection portion that connects the base portion and the annular holding portion in an axial direction, and an annular space partially surrounded by the base portion, the annular connection portion, and the annular holding portion is formed between the outer periphery of the seal ring and an inner periphery of the retainer. The retainer has a plurality of beams which are disposed in the annular space to connect the annular base portion and the annular holding portion.

A mechanical seal assembly adapted for arrangement around a rotating shaft of a pump has first and second seals. Both include primary and mating rings, biasing mechanisms and annular flexible sealing membranes. The two seals can have different seal balances or different biasing forces (or both) to allow the second seal to run dry for extended periods.

The rotary face seal with magnet loading replaces known spring mechanisms with magnetic technology that provides a consistent load with minimal variation, which is not affected by natural frequency and material fatigue due to cyclic loading. This improves seal performance and service life. The tubular magnetic ring is advantageous because it replaces existing seals within stationary cartridge with a puller type magnetic assembly design that results with the stationary cartridges being an exact exchange. The use of magnetic technology attached to the outside diameter of the rotating mating ring, which is attached to the shaft, that does not produce eddy currents because it is of a single pole configuration. The single pole magnetic assembly design is achieved by either axial or radial magnet orientation, such as in the form of a tubular magnetic band locating in a circumferential notch in the rotating mating ring.

A sliding component includes a pair of seal rings which are arranged to rotate relative to each other. The seal rings have sliding surfaces, respectively, which are facing each other. The sliding surfaces are provided with: a land continuously extending in a circumferential direction; inward recessed portions recessed in an axial direction, extending to a radially inner side, and open to the radially inner side; and outward recessed portions recessed in the axial direction, extending to a radially outer side, and open to the radially outer side.