The invention relates to a two-steel screw comprising a top part and a cutting part, the top part consisting of a corrosion-resistant material and having a screw head and a shank portion, and the cutting part consisting of a hardenable material, the top part being permanently connected to the cutting part in the region of the shank portion by way of impact extrusion.

A fastener for securing a substrate to an underlying roof structure, comprising a head and an elongate shank extending therefrom, the shank having a threaded section and a drilling tip, with the drilling tip being configured to enable the fastener to be self-drilling, and wherein the head is configured to be arranged substantially flush with the substrate when the substrate is secured to the roof structure by the fastener.

A double ended dual attached fastener includes a first portion having a stud bolt, a second portion configured to anchor to a panel member, and a flange nut partitioning the first end and the second end. The flange nut includes a flat interior annular surface facing the second portion. The flange nut includes a plurality of radially spaced weld projections extending toward the second portion. The weld projection includes a material that amendable to form a weld joining the flange nut to a panel member through which the second portion is inserted. The second portion defines a fastener selected from a group consisting of a self-tapping friction screw, a self-piercing rivet, and a swage bolt.

Screw for introducing into an underground, comprising a screw shaft and a screw head which is adjoining the screw shaft, in which a drive is formed for rotary driving the screw by a drive element, wherein the drive comprises a hollow wing section at an outer side of the screw with a circular hollow core and hollow wings which are provided along the circumference, wherein the drive comprises a hollow recess section at an inner side of the screw, and wherein the drive at a transition between the hollow wing section and the hollow recess section comprises a chamfer section whose outer surface is angled with respect to an outer surface of the hollow wing section and with respect to an outer surface of the hollow recess section.

The invention relates to a screw and a screw assemblage. The screw includes a screw head and a screw shaft which protrudes from an underside of the screw head and has a self-forming or self-cutting thread. The underside of the screw head has a bearing area and at least one annular recess extending around the shaft between the bearing area and the shaft. A coating made of an elastic sealant is attached to the underside of the screw head. The invention further relates to a method for manufacturing an electrically conductive assemblage.

A screw with an asymmetrical thread for securing wooden members together is disclosed. The screw includes a shaft with a head at one end and a tip at the other end. A continuous asymmetrical thread extends along the shaft. The asymmetrical thread has a front surface facing the tip and a rear surface facing the head, the front and rear surfaces each having an angle relative to a plane normal to the shaft. The asymmetrical thread has a first section and a second section. The portion of asymmetrical thread in the first section has front and rear surfaces of first angles with respect to the plane normal to the shaft. The portion of asymmetrical thread in the second section has front and rear surfaces of second angles different than the first angles. The asymmetrical thread includes a transition portion between the first and second sections. The transition portion is positioned along the shaft such that the transition portion is located proximate the interface of the wooden members when the screw secures the wooden frame members together and the head of the screw engages the first of the wooden members.

A building structure including a first building member and a second building member may be connected by a plurality of fasteners, each fastener having a head, a threaded portion having a through hardness of between HRB 70 and HRC 40, a thread-forming portion of at least HRC 50 hardness enabling the fastener to form threads in at least the second steel building member, and a fluted lead portion of at least HRC 50 hardness with a nominal diameter between 70 and 95% of major diameter, such that the fastener is capable of providing a ratio of strip torque to thread-forming torque of at least 3.0 and a ratio of strip torque to drive torque greater than 6.0 when the second steel building member having a thickness of 0.25 inch and the fluted lead portion having at least one diameter within nominal diameter between 80 and 98% of major diameter.

A self-drilling screw includes a shank and at least one thread. The shank includes a self-drilling portion, a head portion spaced from the self-drilling portion along a longitudinal axis, and a straight rod portion between the self-drilling portion and the head portion. The thread is spirally formed on the straight rod portion and includes a plurality of thread convolutions. Each thread convolution is provided with three to eight recesses spaced apart circumferentially, and a screw thread portion is formed between two adjacent recesses. The recess features a recess length circumferentially, and the screw thread portion features a screw thread length circumferentially. The screw thread length is 25% to 200% of the recess length. The self-drilling screw can be driven into articles to be fastened quickly without loss of binding forces between the self-drilling screw and the articles.

A method of constructing a building comprising the steps of attaching a first panel to a second panel. The first panel is one of a single plenum panel and a multi-plenum panel and the second panel is one of a single plenum panel and a multi-plenum panel.

A fastening structure includes: plural overlapping co-fastened members, a clearance hole being formed at at least one mating face of mutual mating faces of the plural co-fastened members, and a screw utilizing frictional heat to bore a hole and form a thread, passing through the clearance hole, and fastening the plural co-fastened members together.