Various implementations include a ring material used for producing a ring molded article. The ring molded article has two convex portions which respectively protrude on opposite sides of the ring molded article in a direction of a center axis thereof and extend in a direction of a circumference of the ring molded article. A straight line passing through centers of gravity of first and second side regions is inclined by an angle relative to the center axis of the ring material, the first and second side regions are obtained by virtually dividing a one half section of the ring material based on a middle of a maximum height of the ring material in the direction of the center axis of the ring material, and a range of the angle is 7 degrees to 40 degrees.

A forging and inclined window hole punching composite die includes an upper die holder, a connection sleeve, an upper die sliding sleeve, a pressure plate, inclined window puncher pins, a center puncher pin, first connection screw rods, first springs, second connection screw rods, second springs, hydraulic assistant systems, a lower die and a bottom plate. Bottom surface of the pressure plate of the composite die is a plane to avoid deformation of a front molding surface. Hydraulic power is added to the inclined window puncher pins to increase the pressure for punching inclined holes, avoid quality problems and increase a demolding force. A multi-split synchronous hydraulic device may well realize synchronization of the plurality of inclined window puncher pins.

The brake disc includes two first members and at least one second member. Each of the first members has a sliding surface, and has almost a disc shape or an almost annular plate shape. The second member has a plurality of fins and a fin holding part. Each of the two first members and the at least one second member is manufactured by pressing. The brake disc is manufactured as the two first members and the at least one second member manufactured by pressing are joined to each other.

The brake disc includes two first members and at least one second member. Each of the first members has a sliding surface, and has almost a disc shape or an almost annular plate shape. The second member has a plurality of fins and a fin holding part. Each of the two first members and the at least one second member is manufactured by pressing. The brake disc is manufactured as the two first members and the at least one second member manufactured by pressing are joined to each other.

A wheel automatic closed die forging production line includes a sawing machine, a first transfer track, a bar heating furnace, a first manipulator, an oscillating rolling machine, a second manipulator, a primary forging hydraulic machine, an intermediate heating furnace, a third manipulator, a finish forging hydraulic machine, a wheel transfer block, a fourth manipulator, a cutting, expanding and punching hydraulic machine, a second transfer track, a spinning machine, a fifth manipulator, a third transfer track, a heat treatment furnace, a fourth transfer track, a machining unit, a sixth manipulator and a fifth finished product track, and can improve mechanical and the physical properties of the wheel product, the wheel forging effect and the yield. Aluminum and magnesium alloy wheel compression molding is realized, reducing cost, time and labor for secondary machining and reshaping, and improving production safety and efficiency.

Aluminum wheels include a rim and a disc having a mounting portion. The mounting portion includes an inner mounting face and an outer mounting face. The mounting portion also includes a coarse grain region and a fine grain region. The coarse grain region can be adjacent, and at least partially form, one of the inner mounting face or the outer mounting face. The coarse grain region includes aluminum alloy grains of a first average grain length that is greater than 1 mm. The fine grain region extends between the coarse grain region and the other of the inner mounting face or the outer mounting face. The fine grain region includes aluminum alloy grains of a second average grain length that is less than 0.5 mm.

Aluminum wheels include a rim and a disc having a mounting portion. The mounting portion includes an inner mounting face and an outer mounting face. The mounting portion also includes a coarse grain region and a fine grain region. The coarse grain region can be adjacent, and at least partially form, one of the inner mounting face or the outer mounting face. The coarse grain region includes aluminum alloy grains of a first average grain length that is greater than 1 mm. The fine grain region extends between the coarse grain region and the other of the inner mounting face or the outer mounting face. The fine grain region includes aluminum alloy grains of a second average grain length that is less than 0.5 mm.

A flywheel energy storage system incorporates various embodiments in design and processing to achieve a very high ratio of energy stored per unit cost. The system uses a high-strength steel rotor rotating in a vacuum envelope. The rotor has a geometry that ensures high yield strength throughout its cross-section using various low-cost quenched and tempered alloy steels. Low-cost is also achieved by forging the rotor in a single piece with integral shafts. A high energy density is achieved with adequate safety margins through a pre-conditioning treatment. The bearing and suspension system utilizes an electromagnet that off-loads the rotor allowing for the use of low-cost, conventional rolling contact bearings over an operating lifetime of several years.

A flywheel energy storage system incorporates various embodiments in design and processing to achieve a very high ratio of energy stored per unit cost. The system uses a high-strength steel rotor rotating in a vacuum envelope. The rotor has a geometry that ensures high yield strength throughout its cross-section using various low-cost quenched and tempered alloy steels. Low-cost is also achieved by forging the rotor in a single piece with integral shafts. A high energy density is achieved with adequate safety margins through a pre-conditioning treatment. The bearing and suspension system utilizes an electromagnet that off-loads the rotor allowing for the use of low-cost, conventional rolling contact bearings over an operating lifetime of several years.

The invention provides a method and a product for manufacturing a titanium alloy dual-structure turbine disk based on partial hydrogenation, which includes the following steps: coating a glass coating on the partial surface of a titanium alloy billet where hydrogen-blocking is required, and sintering the titanium alloy billet coated with the glass coating; performing hydrogenation treatment on the titanium alloy billet, such that the hydrogen concentration at the hydrogenation-required portion reaches the predetermined level; removing the glass coating from the titanium alloy billet; preheating the titanium alloy billet, and then performing high temperature die forging in the forging dies; performing vacuum dehydrogenation treatment on the forged turbine disk to remove hydrogen element inside the forging, so that the hydrogen content is 0.015 wt. % or less.