JPS63180334A - Method of forming screw thread and tubular body with screw thread formed by said method - Google Patents

Abstract

The production of the internal thread of a connection sleeve (4), which is used as a coupling element for parts of a rock support or of a drill rod, by machine-forming, in particular by thread-cutting, entails great effort since, in the round thread used here, a considerable amount of machining work is required. Furthermore, it is disadvantageous in this application in the machining of the thread that the long-term strength of the connection sleeve is considerably impaired due to the notch effect in the base region of the thread turns. A connection sleeve and a method for its production are proposed, in which the internal thread is produced without machining by shaping the outside of the connection sleeve (4) in the manner of a thread so that the image of this shaping forms the internal thread to be produced on the inside. Apart from the increase in strength caused by the non-cutting shaping, which is usually cold shaping, due to material reinforcement, the further advantage results that the shaping required here can be applied in a single operation so that the production costs of connection sleeves (4) of this type can be reduced. Furthermore, it is advantageous that the external thread, interacting with the internal thread of the connection sleeve, of the components to be connected to one another can have a basic shape which corresponds to the outside thread-type shaping of the connection sleeve (4). <IMAGE>

Description

[Detailed Description of the Invention] The invention further relates to a threaded tubular body formed by the method.

It is common practice to connect extension rods of locking anchors, drilling rods, and the like to each other by means of threaded connections. For this purpose, two parallel drilling rods or locking anchor parts that are connected to each other are connected by a connecting sleeve with an external thread and a corresponding internal thread. Particularly in drilling rods, these threaded parts simultaneously serve as a coupling for coupling a rock hammer or other drive device.

In view of the high load applied and the severe soiling, it is common to use nine threads or something close to a round thread to make these threaded joints easier to handle.

It is well known to produce the internal threads of articulating sleeves such as those mentioned above by cutting processes, in particular by means of thread milling machines or the like. In this case, not only is the cutting amount range of thread cutting disadvantageous, but also the vertical direction of the connecting sleeve is weak due to the cutting amount of the material, and moreover, during cutting, the bottom of the thread turning part, that is, the thread groove part, the sleeve is Notching characteristics occur that adversely affect durability.

The purpose of the present invention is to easily produce a heap at a low cost;
It is an object of the present invention to provide a method for forming threads without cutting, which enables the manufacture of a threaded connection member that guarantees high strength, and a tubular body having threads formed by the method. This object is achieved according to the invention by forming a threaded turn on one side of the tubular cylinder and forming a thread on the other side by copying the threaded turn caused by a corresponding deformation on the opposite side.

The present invention is based on the direct formation of threads by engaging a forming tool on the surface of a tubular member in a well-known non-notched forming process, and this configuration can be applied, for example, to external forming, resulting in The inner formation should occur adjacent to the outer formation. The manufacture of the sleeve begins with a smooth tubular workpiece that receives an internal thread by external molding and annealing the internal thread profile into a round thread. The dimensions of the initial smooth tubular workpiece are sized depending on the dimensions of the reverse threads that are screwed into the sleeve, so that a minimum clearance is provided between the thread turns when screwed together. Internal threads formed in this manner have a significant advantage as they can be manufactured in a single forming configuration.

Compared to thread cutting processes, the manufacturing costs of sleeves with internal threads are considerably reduced.

The production of an internal thread in the sleeve according to claim 2 represents the most important case for implementing the method of the invention. In principle, all non-cutting forming methods can be used for thread manufacturing, including hot forming and cold forming methods. The use of cold forming methods is particularly advantageous due to the low tolerances, as well as the strength of the workpieces, in particular with respect to forming.

The feature recited in claim 3 simply requires some modification of the forming tool for the purpose of adapting to the curved thread side of the female thread as well as for the purpose of setting the necessary gap between the female thread and the male thread. However, it has the advantage that the same working method can be used for both the production of the internal thread and the cooperating external thread.

It is particularly advantageous according to claim 7 to use the method according to the invention for the production of articulating sleeves used for connecting extension rods to locking anchors, drilling rods, etc. In these cases, which are characterized by extremely high 81 negative loads, it is particularly advantageous to reinforce the articulating sleeve with the above-mentioned forming process, thus achieving high strength. Also, in these applications, where severe fouling is possible, round threads or similar threads are preferred for satisfactory handling in extreme conditions of use.

Since the manufacturing method according to the invention is related to the flow of material, it has nothing to do with the actual formed shape (for example, it is suitable for the production of threads of the aforementioned type in which no sharp edges are formed, as occurs in metric threads). In the case of drilling rods, the entire outer shape, including that of the articulating sleeve, is provided with a beveled formation, which facilitates the guidance or evacuation of drilling dust to the outside using the narrow drilled hole. do.

The use of the method according to the invention for the production of articulating sleeves for use in trench supports for excavated water is very advantageous in accordance with claim 8.

It is particularly advantageous that the articulating sleeve according to the invention can be produced in practically any length. A most satisfactory structural shape is also obtained with good guidance of the threaded spindle.

The object of the invention, as far as it relates to a tubular body with a thread and a threaded connection, is achieved by the threaded connection according to the invention and the tubular body according to the invention, which correspond to claims 5 to 8.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to embodiments of the threaded connection member shown in the accompanying drawings.

The rock-cutting end of the gastric anchor, which is also used as a drilling rod, is designated by 1 in FIG. The end 1 therefore consists of a tubular body which supports a known drilling head 2 at its end remote from the drilling ground. The rock drilling head 2 is provided with a central hole (not shown), which serves to guide the rock drilling means.

This central hole communicates with the interior space of the end part 1.

The end 8IS1, i.e. the tubular body 1, has a threaded section 3 which is connected to an extension rod 5 by means of an articulating sleeve 4. Extension rod 5 supports threaded part 6. The extension rod 5, like the end 1, is configured as a tubular body. In principle, a plurality of such extension rods 5 can be articulated with each other, so that the overall length of the locking anchor can be adapted to a wide range of current requirements. Additionally, illustrations of rock anchors disposed in the area of the rock-cutting end to which a rock-drilling hammer or other drive device is coupled during rock-cutting operations have been omitted for clarity.

The threaded parts 3 and 6 of the tubular bodies 1 and 5, which are shown as external threads, and the internal thread of the articulating sleeve 4, which is connected to the threaded part 3.6 (not shown), are in the illustrated embodiment formed as round threads; Round screws can be handled without easily breaking down despite the heavy contamination that occurs during rock drilling operations. According to the invention, the internal thread of the articulating sleeve 4 is formed by a non-cutting forming process, here a cold forming operation, in which the connecting sleeve 4 is formed on the outer side 7 using a forming tool as shown in FIG. forming an internal thread by effectively displacing the material inward to complement the outer contour; Description will be made below with respect to FIGS. 2 to 4. As is clear from the connecting sleeve 4 shown in FIG. 2, the outer side 7 consists of a helical turning deformation part 8 having an arcuate cross section, and between the independent turning deformation parts 8 there is a slightly deformed smooth ground surface. Part 9 stays.

FIG. 3: A threaded turning part 11 is formed on the inner side 10 of the spring sleeve by a molding process, and its cross-sectional shape corresponds to a circular arc, so it can be regarded as a round thread. These screw turning portions 11 are located directly opposite the deformation portion 8 . The gist of the invention is to control the formation of these female thread turns 11 at least sufficiently precisely by means of an effective deformation on the outside, both with respect to the depth and the pitch of the thread, and that the thread turns 11 in this embodiment are connected to the threaded part 3. The main feature is that it can function as a female thread for the male thread formed by 6.

FIG. 4 shows the effective connection in this manner of the internally threaded turn of one articulating sleeve 4 with the externally threaded turn of the other threaded part 3. The threaded parts 3 and 6 are likewise produced in a cold forming process, so that they have a contour that substantially corresponds to that of the outer side 7 of the articulating sleeve 4.

The invention is not limited to its use in connecting sleeves for rock anchors. Basically, it can be used advantageously in all cases where the inside of the tubular body has to be provided with a round thread or an equivalent thread.

FIG. 5 shows an embodiment of an articulating sleeve 4, which allows both sides of the I-cut hole to be used as a counter-groove strut arrangement, thus having two different threaded parts, namely threaded parts 12 of opposite turns. and 13. Into the end of this articulating sleeve 4 a known threaded spindle can be inserted which serves to support the trench wall of the borehole. These threaded spindles have an external contour that essentially corresponds to that of the tubular bodies 1 and 5 of FIG. 1, but these threaded spindles are not shown for the sake of conciseness of the drawing. In order to realize the removal of the threaded spindle or its contact with the groove wall of the borehole which it has to support by rotation of the articulating sleeve 4 relative to the threaded spindle, the articulating sleeve 4 is subjected to a rotational movement in a similar manner, although not shown in the drawing. It is equipped with a mechanism that causes In the simplest case, this auxiliary mechanism can be a hole into which a lever can be inserted. It also serves to enable rotational movement with corresponding tools.

It is also possible to weld a nut or a shaped tube to the connecting sleeve 4. If desired, a plastic nut can be cast or pressed onto the outer surface of the articulating sleeve 4.

Since the articulating sleeve with internal threads formed according to the invention can be formed to any practical length, a particularly reliable articulating sleeve is obtained which improves the bending resistance of threaded spindles of wellbore trench supports. It will be done. At the same time, this method allows the separating part of the column to be made relatively small due to the length of the connecting sleeve.

[Brief explanation of the drawing]

The drawings show an embodiment of a tubular body with a thread formed by the method of the present invention, FIG. 1 is a partial front view of a locking anchor simultaneously used as a piercing rod, FIG. 2 is an enlarged front view of a connecting sleeve, and FIG. Figure 3 shows N-1 of the connecting sleeve in Figure 2.
FIG. 4 is a sectional view of a part of the spring joint, and FIG. 5 is a front view of the connecting sleeve of the present invention used for the groove struts on both sides. 1. Drilling side end 2.. Rock drilling head 3.. Threaded portion 4.. Connecting sleeve 5.. Extension rod 6..
Threaded portion 7・Outside 8・Turning deformation portion 9・Smooth ground surface portion 10・Inside 11・Screw turning portion 1
2.Threaded part 13...Threaded part patent applicant G.D. Ankergesellschaft Mitsutveschlenkter

Claims (8)

[Claims] (1) A method of non-cutting forming a thread on one side or surface of a tubular cylindrical body, especially a sleeve, in which a threaded turn is formed on one side of the cylindrical body, and a copy of the threaded turn formed by a corresponding deformation on the opposite side. A method for forming threads, which is characterized by forming threads by drilling. (2) A patent characterized in that a thread is formed on the inner side 11 of the tubular cylinder, and a thread turning part is formed on the outside 8 of the cylinder using room temperature deformation processing such as rolling, flat processing, press processing, etc. A method for forming a thread according to claim 1. (3) The basic shape of the thread profile formed by the threaded turn on the outside 8 or other side of the cylindrical body is used as a counter-profile for the threaded connection; or Thread forming method according to item 2. (4) A tubular body having a female thread having a shape similar to a round thread, particularly in the connecting sleeve 4, the female thread being deformed into a male thread shape, particularly a copy of the normal temperature deformation. (5) The tubular body according to claim 4, characterized in that the connecting sleeve is formed with threads running in opposite directions from both ends of the connecting sleeve 4 to the middle thereof. (6) A tubular body having a male thread having a shape similar to a round thread, characterized in that the male thread is a deformed copy of the female thread, preferably deformed at room temperature. (7) In a tubular body used for threaded connection between two cylindrical hollow members, such as rock anchors or drilling rods, the ends of the members to be connected to each other are provided with external threads,
5. The tubular body according to claim 4, wherein the external thread profile matches the basic shape of the thread-like deformation formed on the outside of the tubular body forming the threaded sleeve. (8) In a tubular body used for threaded connection between two cylindrical hollow members, in particular threaded spindles of groove struts, the ends of the threaded spindles that are connected to each other are provided with male threads, the male thread profile forming the connection sleeve 4. The tubular body according to claim 4 or 5, characterized in that the thread-shaped deformation formed on the outside of the tubular body has a basic shape that corresponds to the basic shape.