Abstract: A device for measuring undulation of a brake disc in a railway wheel with brake discs includes a wheel support supporting a hub's bore of the railway wheel; a first displacement gauge for measuring a height displacement of the brake disc frictional surface for one round to follow rotation of the wheel support; and a second displacement gauge for measuring a height displacement of a railway wheel rim surface for one round to follow rotation of the wheel support. A computing unit calculates a difference between maximum and minimum values of the height displacement of the frictional surface by acquiring measurement data from the first displacement gauge, calculates a difference between the maximum and minimum values of the height displacement of the rim's surface by acquiring measurement data from the second displacement gauge, and derives a difference between the both calculated differences as brake disc undulation.

Abstract: A device for assembling a railway wheel with brake discs, the brake discs arranged to face each other across a railway wheel web and a center-deviation prevention key penetrating the web, includes a disc support supporting an internal hole of one of the brake discs; a wheel support provided concentrically with the disc support within the disc support, and supporting a hub's bore of the railway wheel on the brake disc supported by the disc support; and a bolt support provided concentrically with the disc support and the wheel support outside of the disc support, and supporting the bolt to correspond to bolt holes formed in the brake discs and the web of the railway wheel. The disc support and the wheel support are individually rotatable about a railway wheel central axis. The disc and wheel supports and the bolt support move up and down relatively to each other.

Abstract: A device for assembling a railway wheel with brake discs, the brake discs arranged to face each other across a railway wheel web and a center-deviation prevention key penetrating the web, includes a disc support supporting an internal hole of one of the brake discs; a wheel support provided concentrically with the disc support within the disc support, and supporting a hub's bore of the railway wheel on the brake disc supported by the disc support; and a bolt support provided concentrically with the disc support and the wheel support outside of the disc support, and supporting the bolt to correspond to bolt holes formed in the brake discs and the web of the railway wheel. The disc support and the wheel support are individually rotatable about a railway wheel central axis. The disc and wheel supports and the bolt support move up and down relatively to each other.

Abstract: A device for measuring undulation of a brake disc in a railway wheel with brake discs includes a wheel support supporting a hub's bore of the railway wheel; a first displacement gauge for measuring a height displacement of the brake disc frictional surface for one round to follow rotation of the wheel support; and a second displacement gauge for measuring a height displacement of a railway wheel rim surface for one round to follow rotation of the wheel support. A computing unit calculates a difference between maximum and minimum values of the height displacement of the frictional surface by acquiring measurement data from the first displacement gauge, calculates a difference between the maximum and minimum values of the height displacement of the rim's surface by acquiring measurement data from the second displacement gauge, and derives a difference between the both calculated differences as brake disc undulation.