A track link which is a tracked undercarriage component is made of a steel having a specific component composition, and includes a high hardness portion having a hardness of HRC 57 or more and HRC 60 or less, and a low hardness portion. The high hardness portion includes a first matrix including a martensite phase and a residual austenite phase, and first nonmetallic particles dispersed in the first matrix and including at least one species selected from the group consisting of MnS, TiCN, and NbCN, and it does not include a M.sub.23C.sub.6 carbide. The low hardness portion includes a second matrix including a martensite phase, and second nonmetallic particles dispersed in the second matrix and including at least one species selected from the group consisting of MnS, TiCN, and NbCN, and it does not include a M.sub.23C.sub.6 carbide.

A link assembly includes a first member, a second member opposing the first member and being rotatable around a rotating shaft, a seal housing formed between the first and second members, and a seal assembly disposed inside the seal housing. The seal assembly has a seal ring and a load ring. The seal ring has a support ring and a lip ring. The seal ring is disposed between the first member and the load ring. The load ring is disposed between the seal ring and the second member. The lip ring abuts the load ring. The lip ring has a first lip part that abuts the first member and protrudes in an axial direction of the rotating shaft, and a second lip part that abuts the second member and protrudes in a radial direction perpendicular to the rotating shaft.

A link assembly includes a first member, a second member opposing the first member and being rotatable around a rotating shaft, a seal housing formed between the first and second members, and a seal assembly disposed inside the seal housing. The seal assembly has a seal ring and a load ring. The seal ring has a support ring and a lip ring. The seal ring is disposed between the first member and the load ring. The load ring is disposed between the seal ring and the second member. The lip ring abuts the load ring. The lip ring has a first lip part that abuts the first member and protrudes in an axial direction of the rotating shaft, and a second lip part that abuts the second member and protrudes in a radial direction perpendicular to the rotating shaft.

A track joint assembly includes adjacent first and second track links each having an elongate link body with an upper rail surface located in part upon first and second link body ends and in part upon a middle section of the link. The upper rail surface forms part of a track rail having a segment formed by each of the middle sections of the elongate link bodies of the first and second track links and a compound segment formed by the two adjacent track links. The upper rail surface is formed of a sacrificial wear material that has a varying cross-sectional area structured to limit scalloping of the track links.

A track joint assembly includes adjacent first and second track links each having an elongate link body with an upper rail surface located in part upon first and second link body ends and in part upon a middle section of the link. The upper rail surface forms part of a track rail having a segment formed by each of the middle sections of the elongate link bodies of the first and second track links and a compound segment formed by the two adjacent track links. The upper rail surface is formed of a sacrificial wear material that has a varying cross-sectional area structured to limit scalloping of the track links.

An apparatus for cleaning the outer side of the hull of a marine vessel and for cleaning the wall of cargo holds, the apparatus including a housing provided with magnetic continuous tracks at opposing lateral sides of the housing, a front wheel and a rear wheel for each of the magnetic continuous tracks, each magnetic continuous track including a plurality of links interconnected by drive pins, the links having an inwardly facing side and an outwardly facing side, a guide configured to engage the drive pins for preventing the links in a first portion of the extent of the of at least one of the magnetic continuous tracks between the front wheel and the rear wheel from moving in the direction in which the outwardly facing side faces and a submersible apparatus for cleaning the outer side of the hull of a marine vessel and for cleaning the wall of cargo space in the cargo holds that comprises a watertight housing provided with continuous magnetic tracks at opposing lateral sides of the housing. A watertight housing provided with continuous magnetic tracks at opposing lateral sides of said housing. At least one drive motor in the housing operably connected to at least one continuous magnetic track for driving the continuous magnetic tracks. The housing being provided with a main side between the continuous magnetic tracks.

An apparatus for cleaning the outer side of the hull of a marine vessel and for cleaning the wall of cargo holds, the apparatus including a housing provided with magnetic continuous tracks at opposing lateral sides of the housing, a front wheel and a rear wheel for each of the magnetic continuous tracks, each magnetic continuous track including a plurality of links interconnected by drive pins, the links having an inwardly facing side and an outwardly facing side, a guide configured to engage the drive pins for preventing the links in a first portion of the extent of the of at least one of the magnetic continuous tracks between the front wheel and the rear wheel from moving in the direction in which the outwardly facing side faces and a submersible apparatus for cleaning the outer side of the hull of a marine vessel and for cleaning the wall of cargo space in the cargo holds that comprises a watertight housing provided with continuous magnetic tracks at opposing lateral sides of the housing. A watertight housing provided with continuous magnetic tracks at opposing lateral sides of said housing. At least one drive motor in the housing operably connected to at least one continuous magnetic track for driving the continuous magnetic tracks. The housing being provided with a main side between the continuous magnetic tracks.

A drive system for a net cleaner to produce efficient propulsion without damage to the cage net. The drive system includes flexible engagement stumps protruding from a base of a driving belt with tips or studs mounted on an end of the stumps. The tips or studs engage the net and propel the net cleaner. The stumps flex to insure that, if excessive pressure is applied to a stud, the stump will bend and the net will release without damage. A guard prevents the stump from directly engaging a cage net. A track belt produces efficient propulsion without damage to the cage net. The track belt includes flexible engagement stumps protruding from a base of a driving belt with tips or studs mounted on an end of the stumps.

A track shoe assembly includes a pad portion, and a grouser that extends from the pad portion along a direction that is perpendicular to the pad portion, terminating at a free end. A first cap is attached to the grouser, at least partially covering the free end of the grouser. The cap comprises a wear resistant material such as a white iron material or a carbide material.

A track shoe assembly includes a pad portion, and a grouser that extends from the pad portion along a direction that is perpendicular to the pad portion, terminating at a free end. A first cap is attached to the grouser, at least partially covering the free end of the grouser. The cap comprises a wear resistant material such as a white iron material or a carbide material.