The present disclosure provides 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, wherein 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, wherein a coating made of an elastic sealant is attached to the underside of the screw head.

The present disclosure provides 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, wherein 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, wherein a coating made of an elastic sealant is attached to the underside of the screw head.

A fastener includes a shank having a first end and a second end defining a length. The fastener includes a thread provided on the shank, the thread including a first region adjacent to the first end and a second region between the first region and a head at the second end, the thread includes a leading edge and a trailing edge, each edge forming an angle with a surface of the shank, the leading edge forming a non-normal angle with the surface of the shank and the trailing edge forming an angle about normal to the surface of the shank. The fastener may include an arcuate detent region in the shank between respective turns of the thread, the detent region having a length, the length decreasing from the first end toward the second end between the respective turns. The fastener may include a plurality of flutes positioned along a length of the shank.

A fastener includes a shank having a first end and a second end defining a length. The fastener includes a thread provided on the shank, the thread including a first region adjacent to the first end and a second region between the first region and a head at the second end, the thread includes a leading edge and a trailing edge, each edge forming an angle with a surface of the shank, the leading edge forming a non-normal angle with the surface of the shank and the trailing edge forming an angle about normal to the surface of the shank. The fastener may include an arcuate detent region in the shank between respective turns of the thread, the detent region having a length, the length decreasing from the first end toward the second end between the respective turns. The fastener may include a plurality of flutes positioned along a length of the shank.

A fastener includes a shank having a first end and a second end defining a length. The fastener includes a thread provided on the shank, the thread including a first region adjacent to the first end and a second region between the first region and a head at the second end, and a pilot thread. The pilot thread may have first second and third revolutions with different heights and widths which are designed to remove various portions of material from a pre-drilled hole into which the fastener is to be inserted.

An assembly for connecting a wooden sill plate to a concrete foundation slab. The assembly comprises a tapping drill bit and an anchor device. The tapping drill bit comprises a flute having a first flute section and a second flute section, the first flute section being longer and having a smaller diameter than the corresponding dimensions of the second flute section. The anchor device comprises a first anchor section and a second anchor section. The anchor device is structured such that the first anchor section is configured for embedment into the concrete foundation slab, and the second anchor section is configured for embedment in the wooden sill plate. The anchor device thereby delivers an advantageous distribution of shear forces that act on the wooden sill plate in relation to the concrete floor slab.

A thread-forming screw which is provided in particular for thin, perforated sheet metal contains a threaded shank which below the screw head is initially configured so as to be cylindrical and then continues to a conical forming portion. The screw shank within the forming portion has a rib forming an incomplete counter thread.

A screw structure is disclosed herein. It comprises a head; a rod body integrally extended from the head and having a flat shank part and a tapered tip at a terminal of the flat shank part; a first screw thread disposed on the rod body and having a positioning tooth at a terminal thereof, a plurality of cutting units and a plurality of shaving collection spaces; a plurality of second screw threads disposed on the rod body; and a reamer thread disposed at an upper end of the rod body.

A method for rating a fastener arrangement that includes a mineral substrate having a hole and a screw which is disposed in the hole, includes unscrewing the screw out of the hole, following the unscrewing, optically inspecting the hole for presence or absence of grout in the hole, and rating the hole as satisfactory when grout has been optically detected in the hole and rating the hole as unsatisfactory when grout has not been optically detected in the hole.

A combined thread forming and thread locking fastener is disclosed. A fastener includes three thread zones. A first thread zone utilizes a first thread forming thread profile with an increasing outer diameter. A second thread zone extends from the end of the first zone utilizing the first thread forming thread profile and continues with a constant diameter. The third thread zone utilizes a thread locking thread profile continuing along substantially the remainder of the shaft of a fastener.