A propeller blade retention element comprises a body portion formed of a corrosion resistant metal, and at least one bearing race portion attached to the body portion, the race portion being formed of an induction hardenable, corrosion resistant metal.

A propeller blade retention element comprises a body portion formed of a corrosion resistant metal, and at least one bearing race portion attached to the body portion, the race portion being formed of an induction hardenable, corrosion resistant metal.

In this steel component, the concentration of C in a surface layer is 0.85 mass % or more to 1.2 mass % or less, which is higher than the concentration of C in a starting material steel, the surface layer has a volume ratio of a retained-austenite structure higher than 0% and lower than 10%, the remainder of the surface layer is a martensitic structure, the area fraction of grain boundary carbides in the surface layer is lower than 2%, a layer inside the surface layer is higher than the surface layer in a volume ratio of a retained-austenite structure, and in the layer inside the surface layer, the remainder is a martensitic structure.

In this steel component, the concentration of C in a surface layer is 0.85 mass % or more to 1.2 mass % or less, which is higher than the concentration of C in a starting material steel, the surface layer has a volume ratio of a retained-austenite structure higher than 0% and lower than 10%, the remainder of the surface layer is a martensitic structure, the area fraction of grain boundary carbides in the surface layer is lower than 2%, a layer inside the surface layer is higher than the surface layer in a volume ratio of a retained-austenite structure, and in the layer inside the surface layer, the remainder is a martensitic structure.

A process of manufacturing of segment for carbon thrust bearing uses stainless-steel (SS) round bars/sheets/logs of suitable grade as raw material. The SS round bars/sheets/logs undergo cutting operation to cut into SS billets. The billets successively undergo heating and hot forging processes to form segments of desired shapes. Thereafter, the segment is subjected to heat treatment process i.e. stress relieving, hardening and tempering process successively for obtaining consistent and uniform grain structure, mechanical properties and physical properties of segments which are cost-effective in terms of lower maintenance and lower handling efforts. After heat-treatment process, segment undergoes surface-finishing processes i.e. grinding, lapping and polishing successively for obtaining mirror like surface finishing that gives greater anti-friction property and lower co-efficient of friction. The manufacturing process according to present invention yields consistent grain structure, refine, dense and uniform microstructure of segments which imparts optimum strength, ductility, toughness and resistance to impact and fatigue.

An induction heating system includes an induction heating head assembly configured to move relative to a workpiece. The induction heating system may also include a temperature sensor assembly configured to detect a temperature of the workpiece and/or a travel sensor assembly configured to detect a position, movement, or direction of movement of the induction heating head assembly relative to the workpiece, and to transmit feedback signals to a controller configured to adjust the power provided to the induction heating head assembly by a power source based at least in part on the feedback signals. In certain embodiments, the induction heating system may also include a connection box configured to receive the feedback signals, to perform certain conversions of the feedback signals, and to provide the feedback signals to the power source. Furthermore, in certain embodiments, the induction heating system may include an inductor stand assembly configured to hold the induction heating head assembly against the workpiece.

An induction heating system includes an induction heating head assembly configured to move relative to a workpiece. The induction heating system may also include a temperature sensor assembly configured to detect a temperature of the workpiece and/or a travel sensor assembly configured to detect a position, movement, or direction of movement of the induction heating head assembly relative to the workpiece, and to transmit feedback signals to a controller configured to adjust the power provided to the induction heating head assembly by a power source based at least in part on the feedback signals. In certain embodiments, the induction heating system may also include a connection box configured to receive the feedback signals, to perform certain conversions of the feedback signals, and to provide the feedback signals to the power source. Furthermore, in certain embodiments, the induction heating system may include an inductor stand assembly configured to hold the induction heating head assembly against the workpiece.

A rolling apparatus including an external member having a raceway surface on an inner peripheral surface thereof, an internal member having a raceway surface on an outer peripheral surface thereof, and a plurality of rolling elements which are rotatably provided between the raceway surface of the external member and the raceway surface of the internal member. A surface of at least one of the internal member, the external member, and the rolling elements is subjected to carbonitriding or nitriding; an area percentage of a nitride containing Si and Mn is 1% or more and 20% or less; surface hardness is HV750 or more. When depth from the raceway surface or depth from a rolling surface of the rolling element is defined as Z and diameter of the rolling element is defined as d, hardness at Z=0.045 d is HV650 to 850, and hardness at Z=0.18 d is HV400 to 800.

A rolling apparatus including an external member having a raceway surface on an inner peripheral surface thereof, an internal member having a raceway surface on an outer peripheral surface thereof, and a plurality of rolling elements which are rotatably provided between the raceway surface of the external member and the raceway surface of the internal member. A surface of at least one of the internal member, the external member, and the rolling elements is subjected to carbonitriding or nitriding; an area percentage of a nitride containing Si and Mn is 1% or more and 20% or less; surface hardness is HV750 or more. When depth from the raceway surface or depth from a rolling surface of the rolling element is defined as Z and diameter of the rolling element is defined as d, hardness at Z=0.045 d is HV650 to 850, and hardness at Z=0.18 d is HV400 to 800.

When a rod-shaped workpiece (W) having an outer peripheral surface with a circular cross section is inductively heated to a quenching temperature while being conveyed at a predetermined velocity along an axial direction of the rod-shaped workpiece (W), the rod-shaped workpiece (W) being currently conveyed is heated to a predetermined temperature equal to or lower than the quenching temperature by a first heating coil (2A), which is electrically connected to a first high-frequency power supply (3) and has a constant output. Then, the rod-shaped workpiece (W) being currently conveyed is heated so as to be maintained at the quenching temperature by a second heating coil (2B), which is electrically connected to a second high-frequency power supply (4) and has a constant output.