This threaded fastening element (2) comprising a threading (14) extending along a central axis (A), the threading (14) having at least one screw thread having an apical angle decreasing gradually, continuously and monotonously, between a first apical angle (α1) and a second apical angle (α2) strictly smaller than the first apical angle. The threaded fastening element is a screw or a nut.

A hole expanding screw comprises a screw head and a screw shank. The screw head includes a top and a neck extending from the top and gradually shrinking toward a direction opposite the top. The screw shank includes a shank body connected with the neck, a hole expanding portion connected with the shank body, a cone connected with the hole expanding portion, a thread running helically from the cone through the hole expanding portion to the shank body. The outer diameter of the hole expanding portion is greater than the diameter of the shank body and smaller than the diameter of the thread. The hole expanding portion includes a plurality of hole expanding blocks arranged into several rows and a plurality of debris exhaust channels formed among the hole expanding blocks, wherein each two neighboring rows of the hole expanding blocks are arranged in a staggered way.

A self-drilling screw (10) having a head (20), a shaft (30) at least partially wearing a thread (35) and a drill point (40). The base material of the screw (10) including the drill point (40) is integrally manufactured from an austenitic 300 series steel with a surface hardness (uncoated) of 400-600 HV 0.3. The surface of the screw has a top coating of Zn—Ni with a Ni-content between 12-15% deposited on the austenitic base material. This self-drilling screw (10) is manufactured from a blank of raw austenite 300 series steel which is initially squeezed by cold forming to reduce its diameter in a first operation and, in following cold forming operations the head, the drill point and a thread are formed.

A flooring screw comprises a screw head, a screw shank connected with the screw head, and a cone connected with screw shank. The screw shank includes a first shank section connected with the screw head, a second shank section connected with the cone, a first thread formed on the first shank section, a second thread extended from the cone to the second shank section and running helically along a direction opposite the direction of the first thread, and a third shank section between the first shank section and the second shank section. The third shank section includes a plurality of peaks protruding outward radially and a plurality of troughs formed between the peaks and recessed radially with respect to the peaks. The peaks and the troughs form an unsmooth surface on the third shank section.

The invention relates to a screw (10) including a head (12), a shaft (14), and a thread (16), with the thread (16) having at least two different thread sections (18, 20), with an external diameter D.sub.Gn of a thread section (18) near the head being smaller than an external diameter D.sub.Gf of a thread section (20) distant from the head and greater than an external diameter D.sub.Sf of the shaft (14) in the area of the thread section (20) distant from the head. According to the invention it is provided that the thread (16) extends up to the bottom of the head (12). The invention further relates to a fastening arrangement (24), the use thereof, and a method.

A wall anchor for use in a cavity wall includes an elongate body having a driven end portion and a driving end portion. The driven end portion is adapted to be threadedly mounted on the inner wythe of the cavity wall. The elongate body includes a barrel portion adjacent the driven end portion. A first end of the barrel portion is adapted to abut the inner wythe of the cavity wall when installed. A thermal coating is disposed on the first end of the barrel portion. The thermal coating is configured and arranged to reduce thermal transfer in the cavity wall between the elongate body and the inner wythe when installed.

A screw includes a head and a shank extending from the head, and a hole-enlarging portion formed on the shank. The hole-enlarging portion features no thread and a substantially triangular transverse section. The hole-enlarging portion includes three inclined edges spaced from one another in the circumferential direction of the shank, and a guiding slope is formed between two adjacent inclined edges. The shank defines a longitudinal axis and is provided with a thread. Each inclined edge extends toward the head in an inclined direction relative to a horizontal axis perpendicular to the longitudinal axis. The inclined direction of each inclined edge is identical to a direction in which the thread extends toward the head.

The present invention provides a fastening element for increasing fixing stability, the fastening element having a drill part formed at the bottom tip of the lower end of a fixing piece so that a fixing groove can be easily formed by means of the drill part when the fixing groove is formed on a structure, wherein one side of the drill part is formed to be pointed and the other side thereof is formed to be blunt so that the fastening element is easily screw-fastened to the fixing groove of the structure and, simultaneously, can be prevented from being loosened by external vibration and the like. The present invention has a protruding part protruding downward from the lower surface of a flange, so that the protruding part is pressed and fixed to the upper surface of the structure so as to enable the fastening element to be more firmly fixed to the structure. In addition, a polygonal upper flange is formed on the upper surface of the flange, and thus a fastening part or the upper flange of the fixing piece is fastened using a wrench and the like, so that the fastening element can be easily fixed onto the structure.

A screw and anchor assembly include a male fastener and a female anchor. The male fastener only has threads or half-circular fins on half of the surface area. The other half is just like a regular cylinder. The female anchor only has threads or half-circular fins on half of the inner surface area. The other half is just like the inner wall of a regular cylinder. The user may push the male fastener into the female anchor, so the half-circular fins on the male fastener engages with the half-circular fins inside the female anchor and locks the male fastener to the female anchor. When the user needs to remove the male fastener, simply turns the male fastener 180 degrees and disengages the half-circular fins on the male fastener from the half-circular fins on the female anchor, then pull the male fastener from the female anchor.

A cold formed anchor for use in an insulated cavity wall includes a unitary body formed with a driver portion and having large and small diameter portions. The driver portion may be formed with structure for connecting a veneer tie to the anchor. A method of making the cold formed anchor includes cold forming a driver portion and a reduced diameter portion from a blank.