A device for cold rolling a thread on a tubular support member of a rotary shouldered thread connection includes obtaining an original root depth of a thread root, cold rolling the thread until a minimum increased root depth tolerance is achieved.

A method of cold rolling a thread on a tubular support member of a rotary shouldered thread connection includes obtaining an original root depth of a thread root, cold rolling the thread until a minimum increased root depth tolerance is achieved. The thread may be cold rolled with a wheel tip having an elliptical profile.

Provided is a method for performing an external pipe thread process on a hollow blank by at least twice rolling, wherein amount of rolling wheels in a rolling wheel set, used in any two back-to-back rolling processes in a processing sequence, are different in parity. Further provided are various roll-processing modules and corresponding rolling apparatuses, achieving the above processing method and having a simple structure, portability and practicality. A hollow blank is not liable to deform when performing an external pipe thread rolling process thereon, thereby improving a processing yield.

A high-strength screw (1) includes a head (2) having a tool engagement external contour (7) and a tool engagement internal contour (8). For example, the tool engagement external contour (7) is an external hexagonal and the tool engagement internal contour (8) is an internal hexagonal. A plurality of additional pocket-shaped impressions (13) are arranged in the tool engagement internal contour (8) between corners (12).

A thread rolling head includes a bearing housing, in which at least two profile rollers, preferably at least three, are each rotatably mounted on an eccentric shaft. A shank is coupled to the housing, and adjacent profile rollers delimit an insertion section into which a workpiece can be longitudinally inserted. The bearing housing includes two housing parts rotatable relative to each other to change the spacing between the profile rollers. An adjustment element interacts with one of the two housing parts and can rotate about the longitudinal axis thereof. Rotation of the adjustment element in a first direction causes rotation of the two housing parts in a third rotational direction, while its rotation in the second direction causes rotation of the housing parts in a fourth rotational direction counter to the third rotational direction. A display apparatus displays a change of the spacing between the profile rollers.

A thread-rolling apparatus includes a base, a feeding unit, a thread-forming assembly, and a distance-sensing assembly. The base mainly includes a movable portion, a first body, and a second body between the movable portion and the first body. The thread-forming assembly includes cooperating first and second dies and a working passage formed between the dies. The distance-sensing assembly includes at least one sensing unit disposed on the first body and a processing module connected to the sensing unit. The cooperation between the sensing unit and the processing module senses changes in a first distance between the first body and the second body in a non-contact manner whereby abnormal variations can be quickly observed and properly coped, and a second distance of the working passage can be in a normal state. Accordingly, the yield rate of the thread-rolling apparatus can be efficiently increased.

The invention relates to a thread rolling tool for rolling or repairing a thread with a tool body (12) a profiled roller (36) that is mounted on the tool body (12), and at least one counter roller (14.1) that has a counter roller rotational axis (D.sub.14.1) and is mounted on the tool body (12). According to the invention, it is recommended that the profiled roller (36) and/or the at least one counter roller (14) is mounted so that it is axially displaceable.

The invention provides a self-drilling screw structure and a manufacturing method thereof, wherein the manufacturing method includes: providing screw body, forming drill tail screw rod section, forming concave neck portion, forming drill tail cutting edge and forming thread. The self-drilling screw structure including a screw head portion and a screw rod portion, the screw rod portion is sequentially provided with a threaded screw rod section, a drill tail screw rod section and a drill bit screw rod section, the drill tail screw rod section has a rod diameter of drill tail, a plurality of drill tail cutting edges and a plurality of drill tail chip discharge grooves, the drill bit screw rod section is provided with a concave neck portion, and the drill bit screw rod section is protruded to form a plurality of drill bit cutting edges and the plurality of drill bit chip discharge grooves.

A device (20) for root-rolling a thread (T) on an object (O) includes: a body (21), an accumulator piston (24) mounted for sealed sliding movement within a body passageway (22), a coarse adjustment screw (25) threaded onto the body, a Belleville spring stack (26) compressed between the coarse adjustment screw and the accumulator piston, an actuator piston (28A or 28B) mounted for sealed sliding movement within a cylindrical opening (23) in the body, and a thread roll (32) rotatably mounted on the actuator piston. A fine adjustment screw is threaded (33) into a first opening (34) on the body, and communicates with a fluid chamber between the accumulator and actuator pistons. The positions of the coarse and fine adjustment screws may be selectively adjusted to controllably vary the fluid pressure within the chamber. The device may be mounted on a machine tool (35) and selectively moved toward the object to root-roll a thread on the object when the object and device are rotated relative to one another.