A mechanical joint according to which a gasket includes wipers, or protrusions, on an internal surface of the gasket, on an external surface of the gasket, or on both internal and external surfaces of the gasket.

The present invention improves surface roughness by knocking down protruding parts while leaving recessed parts in the surface of a metal product, protrusions/recesses having been formed in said surface via blasting, and improves surface hardness and compressive residual stress. Treatment is performed upon a metal product in which protrusions/recesses have been formed in the surface thereof via blasting. Spherical shot that are less hard than the surface hardness of the metal product and have a particle size that is greater than the width of recessed parts of the protrusions/recesses are sprayed toward and collide against the surface of the metal product as crushing shot, and the protruding parts of the protrusions/recesses formed on the surface of the metal product are selectively knocked down, thereby providing a metal product surface member in which the surface roughness of the metal product has been improved.

The present invention improves surface roughness by knocking down protruding parts while leaving recessed parts in the surface of a metal product, protrusions/recesses having been formed in said surface via blasting, and improves surface hardness and compressive residual stress. Treatment is performed upon a metal product in which protrusions/recesses have been formed in the surface thereof via blasting. Spherical shot that are less hard than the surface hardness of the metal product and have a particle size that is greater than the width of recessed parts of the protrusions/recesses are sprayed toward and collide against the surface of the metal product as crushing shot, and the protruding parts of the protrusions/recesses formed on the surface of the metal product are selectively knocked down, thereby providing a metal product surface member in which the surface roughness of the metal product has been improved.

The present peening calibration unit comprises a casing, a transducer, and a transmission unit. The casing defines a top and a bottom. The transducer is positioned along at least a section of the top of the casing. The transducer generates an electric signal upon application of peening energy thereto. The transmission unit receives the electric signal generated by the transducer and transmits a digital signal representative of the received electrical signal wirelessly. The transmission unit is located inside the casing. Furthermore, a peening calibration battery pack and a peening calibration system are described.

The present peening calibration unit comprises a casing, a transducer, and a transmission unit. The casing defines a top and a bottom. The transducer is positioned along at least a section of the top of the casing. The transducer generates an electric signal upon application of peening energy thereto. The transmission unit receives the electric signal generated by the transducer and transmits a digital signal representative of the received electrical signal wirelessly. The transmission unit is located inside the casing. Furthermore, a peening calibration battery pack and a peening calibration system are described.

A tool bit includes a drive portion configured to be engaged by a tool, the drive portion including a first maximum outer dimension, a shank extending from the drive portion and including a reduced outer diameter, and a tip coupled to an end of the shank opposite from the drive portion. The tip includes a compressive residual stress layer formed by blasting to increase a wear resistance of the tip relative to the shank. The tip additionally includes a second maximum outer dimension. The reduced outer diameter of the shank is smaller than the first maximum outer dimension of the drive portion and the second maximum outer dimension of the tip.

A tool bit includes a drive portion configured to be engaged by a tool, the drive portion including a first maximum outer dimension, a shank extending from the drive portion and including a reduced outer diameter, and a tip coupled to an end of the shank opposite from the drive portion. The tip includes a compressive residual stress layer formed by blasting to increase a wear resistance of the tip relative to the shank. The tip additionally includes a second maximum outer dimension. The reduced outer diameter of the shank is smaller than the first maximum outer dimension of the drive portion and the second maximum outer dimension of the tip.

A stabilizer formed by using a metal bar having a solid structure and configured to reduce a displacement between right and left wheels, including a torsion part extending in a vehicle width direction, being capable of a torsional deformation, and having a diameter of 10 to 32 mm, is provided. The stabilizer has a chemical composition containing at least C: 0.15% by mass or more to 0.39% by mass or less, Mn, B, and Fe, and also has a metal structure 90% or more of which is a martensite structure.

A stabilizer formed by using a metal bar having a solid structure and configured to reduce a displacement between right and left wheels, including a torsion part extending in a vehicle width direction, being capable of a torsional deformation, and having a diameter of 10 to 32 mm, is provided. The stabilizer has a chemical composition containing at least C: 0.15% by mass or more to 0.39% by mass or less, Mn, B, and Fe, and also has a metal structure 90% or more of which is a martensite structure.

The invention provides a production method for stabilizers which produces with high productivity in a compact production line, without tempering. The production method for stabilizers of the invention includes: forming a steel bar material containing at least C: 0.15 wt % to 0.39 wt %, Mn, B and Fe into a product shape by bending; and quenching the bent steel bar material in a medium having a heat transfer coefficient higher than or close to that of water.