A cross edge rolling process for increasing a thickness of a strip in longitudinal edge strips on both longitudinal sides of the strip. According to the invention, this is achieved in that firstly a step extending in the longitudinal direction of the strip is produced by means of a roll profiling process, wherein the strip is supported during the cross edge rolling process on said step against a compression force acting transversely to the strip, so that the strip is not compressed outside the longitudinal edge strip. After the edging process for increasing the thickness of the longitudinal edge strips, the strip is bent by means of a roll profiling process to form a C-profile rail.

A method for manufacturing a protective sheath for a fan blade leading edge is described. The method may comprise generating a preform plate from a stock plate wherein the preform plate has a flattened surface and an inclined surface having a spike flanked by a first side and a second side. The method may further comprise bending the first side and the second side away from the spike to generate a sheath intermediate followed by generating the protective sheath from the sheath intermediate by shaping an outer surface and an inner surface of the sheath intermediate to match the contour of the fan blade leading edge.

This invention relates to a combined ring rolling method for spherical valve body, which has the following procedures: 1) design for ring blank by computing ring blank volume and selecting reasonable rolling ratio according to the dimensions of forged ring; 2) design for rolling gap which includes the shapes and dimensions of working surfaces of main roll, mandrel and passive rolls according to the dimensions of ring blank and forged ring, the stable deformation condition of combined ring rolling and structure requirement of rolling equipment; 3) rolling forming with three stages of surface cross rolling, ring rolling and shaping by controlling of feeding speed of main roll and working positions of passive rolls. This invention has the technical economical advantages of low consumptions of energy and materials, high productivity and low production cost.

This invention relates to a combined ring rolling method for spherical valve body, which has the following procedures: 1) design for ring blank by computing ring blank volume and selecting reasonable rolling ratio according to the dimensions of forged ring; 2) design for rolling gap which includes the shapes and dimensions of working surfaces of main roll, mandrel and passive rolls according to the dimensions of ring blank and forged ring, the stable deformation condition of combined ring rolling and structure requirement of rolling equipment; 3) rolling forming with three stages of surface cross rolling, ring rolling and shaping by controlling of feeding speed of main roll and working positions of passive rolls. This invention has the technical economical advantages of low consumptions of energy and materials, high productivity and low production cost.

Methods and apparatus for an enhanced driving bit according to various aspects of the present technology include a bit comprising a plurality of driving surfaces having a limited length and a shoulder portion positioned between the driving surfaces and a mid-body portion of the bit. The length of the driving surfaces is selected to allow complete insertion into a recessed socket area of a fastener such that the entire driving surface is positioned within the recessed socket area. The shoulder surface is configured to distribute localized stresses away from the driving surfaces to the mid-body portion more efficiently to reduce a potential for breakage of the driving surfaces during use.

Methods and apparatus for an enhanced driving bit according to various aspects of the present technology include a bit comprising a plurality of driving surfaces having a limited length and a shoulder portion positioned between the driving surfaces and a mid-body portion of the bit. The length of the driving surfaces is selected to allow complete insertion into a recessed socket area of a fastener such that the entire driving surface is positioned within the recessed socket area. The shoulder surface is configured to distribute localized stresses away from the driving surfaces to the mid-body portion more efficiently to reduce a potential for breakage of the driving surfaces during use.

Methods and apparatus for an enhanced driving bit according to various aspects of the present technology include a bit comprising a plurality of driving surfaces having a limited length and a shoulder portion positioned between the driving surfaces and a mid-body portion of the bit. The length of the driving surfaces is selected to allow complete insertion into a recessed socket area of a fastener such that the entire driving surface is positioned within the recessed socket area. The shoulder surface is configured to distribute localized stresses away from the driving surfaces to the mid-body portion more efficiently to reduce a potential for breakage of the driving surfaces during use.

Provided is a metal strip for a pipe with which the weight of a pipe can be reduced while maintaining the strength of a joint portion that tends to be structurally the weakest. A metal strip L is formed by rolling. The thickness of each of a head end portion 1a and a tail end portion 1b, which are longitudinal end portions 1, is greater than the thickness of an intermediate portion excluding the longitudinal end portions 1. The metal strips are connected to each other in series by welding, and a pipe is made by performing a pipe-forming operation.

Provided is a metal strip for a pipe with which the weight of a pipe can be reduced while maintaining the strength of a joint portion that tends to be structurally the weakest. A metal strip L is formed by rolling. The thickness of each of a head end portion 1a and a tail end portion 1b, which are longitudinal end portions 1, is greater than the thickness of an intermediate portion excluding the longitudinal end portions 1. The metal strips are connected to each other in series by welding, and a pipe is made by performing a pipe-forming operation.

A driveshaft assembly includes an inner tube. The inner tube has splines formed from a plurality of teeth alternating with a plurality of recesses formed on the inner tube. An outer tube has splines formed from a plurality of teeth alternating with a plurality of recesses formed thereon. The outer tube coaxially receiving the inner tube. The splines of the inner tube engaging the splines of the outer tube. A plurality of protrusions is formed on one of an inner surface of the splines of the outer tube and an outer surface of fewer than an entirety of the plurality of recesses of the splines of the inner tube.