A wire thread insert comprises besides a cylindrical helix consisting of a plurality of coils a moving tang projecting into the interior of the helix for installing the wire thread insert into a receiving thread. The wire thread insert is connected to the cylindrical helix via a bending portion such that the moving tang can be redressed into the receiving thread after installation of the wire thread insert. The wire thread insert is installed by means of an installation tool with a mounting spindle, which installs the wire thread insert in the receiving thread via a moving shoulder and the moving tang. A compression blade provided at the mounting spindle bends the moving tang back into the receiving thread while the mounting spindle is removed from the installed wire thread insert.

A wire thread insert comprises besides a cylindrical helix consisting of a plurality of coils a moving tang projecting into the interior of the helix for installing the wire thread insert into a receiving thread. The wire thread insert is connected to the cylindrical helix via a bending portion such that the moving tang can be redressed into the receiving thread after installation of the wire thread insert. The wire thread insert is installed by means of an installation tool with a mounting spindle, which installs the wire thread insert in the receiving thread via a moving shoulder and the moving tang. A compression blade provided at the mounting spindle bends the moving tang back into the receiving thread while the mounting spindle is removed from the installed wire thread insert.

A high-strength screw (1) includes a head (2) and a threaded portion (5) including a thread (6) and a thread end (9) facing away from the head (2) in an axial direction. The threaded portion (5) includes an unhardened portion (12) starting at the thread end (9) and extending in an axial direction. The unhardened portion (12) has a hardness being reduced compared to an axial middle portion (11) of the threaded portion (5).

A rotary cutter for cutting damaged threads of a bolt includes a body rotatable about a rotating axis and having a connecting end and an operative end. A first cutting blade is disposed on an inner periphery of the body facing a cutting space extending along the rotating axis from the operative end towards but spaced from the connecting end. The body further includes a virtual projection plane perpendicular to the rotating axis. A first virtual plane passes through the first cutting blade and extends perpendicularly to the virtual projection plane. A virtual circle and a first virtual reference line are located on the virtual projection plane. The first virtual reference line intersects the rotating axis and passes through an intersection of the first virtual plane and the virtual circle. An angle between the first virtual reference line and the first virtual plane is between 5 and 40.

A cleaning method allows reliable cleaning of thread roots of a female screw. A cleaning method for a female screw includes producing a jet of a cleaning liquid from a nozzle in a direction tilted from an axis of the female screw without inserting the nozzle in the female screw, and directing the jet to impinge on a thread of the female screw while rotating the jet about the axis.

An embedded nut for fast construction purposes comprises a connecting portion and two nut portions located at two opposite ends of the connecting portion. One end of the nut portion away from the connecting portion defines a nut hole, and the connecting portion protrudes outward in a direction away from a central axis of the two nut portions. Methods for manufacturing the embedded nut and for manufacturing a concrete member with the embedded nut are also provided.

Disclosed is a thread chase or tap capable of being inserted past damaged threads of a female threaded coupling and then rotated back to repair the damaged threads. The thread chase can be selectively expanded to engage chase blocks having cutting teeth against threads. Thereafter, a user can rotate the thread chase in a direction sufficient to cause the thread chase to move axially out of the female threaded coupling. Upon doing so, the chase blocks can be pushed outwardly and engage undamaged threads, and rotated so as to move upward and repair damaged threads.

A high-strength screw (2) includes a threaded portion (7) having a thread (8). The screw (2) includes an inner core (16) as seen in cross-section of the screw (2), the core (16) having a first hardness. The screw (2) includes an outer surface layer (17) as seen in cross-section of the screw (2). The screw (2) includes an unhardening layer (18) forming the outer surface layer (17) in the threaded portion (7), the unhardening layer (18) having a second hardness being reduced compared to the first hardness of the core (16).

A cleaning tool is disclosed for cleaning an object (e.g., a threaded fastener) and retaining debris from cleaning the object. The cleaning tool can comprise a housing operable to be rotated by hand or by a hand tool, and a cleaning chamber formed through the housing. A plurality of retaining cavities are formed through the housing and in fluid communication with the cleaning chamber, and a plurality of cleaning elements (e.g., shafts having bristles) are supported by respective retaining cavities, such that a portion of the cleaning elements (e.g., wire bristles) extend into the cleaning chamber for cleaning the object upon rotation of the housing relative to the object. Elastic elements can be supported by the housing for biasing the cleaning elements to accommodate cleaning different sizes of objects. Associated systems and methods are provided.

A screw includes a barrel-shaped central pin is surrounded by a cylindrical bore having a conical bottom The cylindrical insert is seated in the cylindrical bore. The top surface of the central pin is lowered below the top surface of the head. The walls of the pin (4) are convex towards the insert. Manufacturing the screw includes producing the threaded part with the head with the cylindrical recess with the cone-shaped bottom. The cylindrical insert terminates at one end with a bevel with an inclination angle of =10-30. The insert is introduced into the cylindrical recess. The upper part of the insert protruding from head of the screw is pre-shaped. The pin is upset using an appropriate tool and simultaneously the top surface of the pin is lowered below the top surface of the head.