JPH08219962A - Out-of-plane bending tester for piping elbow - Google Patents

Abstract

PURPOSE: To obtain a highly accurate bending tester being employed in the out-of-plane bending test of a piping elbow or generally employed as an apparatus for applying a bending load to various structures. CONSTITUTION: In order to transmit a rotational force to flange coupling bases 4 being coupled with a piping elbow 2 at the opposite ends thereof, a sectoral moment lever 1 freely turnable about the center of the sector is fixed to each flange coupling base 4 by means of a bearing 9 and a supporting metal 8. A wire 3 is fixed, at one end thereof, to the arcuate part of the moment lever 1 and, at the other end thereof, to a load metal 6 subjected to tensile force P. The wire 3 is held perpendicular to the direction connecting the fulcrums of both moment levers 1 and both wires 3 are set in parallel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an out-of-plane bending test of a pipe elbow and a test device generally used as a device for applying a bending load to various structures.

[0002]

2. Description of the Related Art FIG. 2 shows an example of a conventional pipe elbow out-of-plane bending test apparatus. In the figure, (a) is a side view and (b) is a plan view.

The apparatus of FIG. 2 applies out-of-plane bending to the elbow by a link mechanism. In the figure, the pulling force P'is a pair of moments via the load-bearing metal fitting 6'and the connecting rod 5 which constitutes the link mechanism. The flange coupling base 4'transmitted to the lever 1'and fixed on the moment lever 1'is rotated around the fulcrum pins 7 ', 7', so that the pipe elbow 2 is out-of-plane bent.

[0004]

In the conventional device as described above, as shown in FIG. 3 for explaining the working state of force, the pulling force P'is applied to the moment lever 1 '(length 1) by F, It is transmitted as G component force. Then, the out-of-plane bending moment M _O applied to the pipe elbow 2 becomes Fl ′.

As described above, the conventional device has the following drawbacks.

(1) 1'changes with the deformation, and the linearity between the tensile force P'and the out-of-plane bending moment M _O is not established.

(2) The component force G acts as an in-plane bending moment M _{I on the} elbow, and a pure out-of-plane bending test cannot be performed.

An object of the present invention is to provide a new pipe elbow out-of-plane bending test apparatus that solves the above-mentioned problems.

[0009]

As a constitution for achieving the above object, an out-of-plane bending test apparatus for a pipe elbow according to the present invention is a test apparatus for applying a tensile force to a pipe elbow to load an out-of-plane bending moment, In order to transmit the rotational force to the flange joints that connect to both ends of the pipe elbow,
A fan-shaped moment lever that can freely rotate around the center of the fan is attached to each of the flange coupling bases by a bearing and a support fitting, one end of each wire is attached to the arc portion of each moment lever, and the other end of the wire is attached. Are connected to the load-bearing metal fittings that receive tensile force, and the wire between the moment lever and the load-bearing metal fitting is kept perpendicular to the direction connecting the fulcrums of both moment levers, and both wires are arranged in parallel. It is characterized by having done.

[0010]

In the present invention having the above-described structure, the moment lever is fan-shaped and rotated about the fulcrum so that l'in FIG. 3 can always be made equal to 1, and the tensile force P and the surface The relationship of the external bending moment M _O is always constant.

The force applied to the moment lever is shown in FIG.
Therefore, it is possible to avoid the generation of the in-plane bending moment M _I with respect to the elbow 2.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an out-of-plane bending test apparatus for a pipe elbow according to an embodiment of the present invention, (a) is a side view, and (b) is a plan view.

In the drawing, reference numeral 1 denotes a pair of left and right moment levers formed in a fan shape, the bases of which are respectively connected to the ends of the pipe elbow 2 via a flange coupling base 4.

A wire 3 is attached to an arc portion of each fan-shaped moment lever 1, and each other end of the wire 3 is connected to a load-carrying metal fitting 6. Through the wire 3, a pulling force P is applied to each moment lever 1 Is transmitted to the flange coupling base 4 which is integrally coupled to the flange coupling base 4 to rotate.

Due to the rotation of the flange coupling base 4, a pure out-of-plane bending force is applied to the pipe elbow 2 connected thereto.

The moment lever 1 is supported at its base by a cylindrical supporting point 7, and is freely rotated around a fan-shaped center 10 by a bearing 9 and a support metal fitting 8 which are in contact with the moment-lever 1 and two fan-shaped centers. It can move freely in the direction of connecting 10 and transmits only the rotational force to the flange coupling base 4.

The wire 3 between the moment lever 1 and the loading metal fitting 6 is kept at a right angle to the direction connecting the fulcrums of both moment levers 1, and both wires 3 are arranged in parallel.

Since the moment lever 1 is fan-shaped and rotates about a fulcrum, the moment lever length l is always constant, and the relationship between the tensile force P and the out-of-plane bending moment M _O is always constant. At the same time, the force applied to the moment lever 1 is only F in FIG.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various design changes are possible within the scope of the technical idea of the present invention.
All of them belong to the technical scope of the present invention.

[0020]

As described above, according to the present invention, the relationship between the tensile force and the out-of-plane bending moment is always constant and the linearity can be maintained.

Further, the force applied to the moment lever can be concentrated because the component force is removed, a pure out-of-plane bending moment can be applied to the elbow, and the accuracy of the test apparatus can be improved.

[Brief description of drawings]

FIG. 1 shows an out-of-plane bending test apparatus for a pipe elbow according to an embodiment of the present invention, (a) is a side view and (b) is a plan view.

FIG. 2 shows an example of a conventional pipe elbow out-of-plane bending test apparatus, in which (a) is a side view and (b) is a plan view.

FIG. 3 is an explanatory diagram showing how a force works.

[Explanation of symbols]

 1 Moment Lever 2 Piping Elbow 3 Wire 4 Flange Coupling 6 Loaded Bracket 7 Support 8 Support Bracket 9 Bearing 10 Fan-shaped Center

Claims (1)

[Claims] 1. In a test device for applying a tensile force to a pipe elbow to apply an out-of-plane bending moment, in order to transmit a rotational force to a flange coupling base connected to each end of the pipe elbow, a fan-shaped bearing and a support bracket are used. A fan-shaped moment lever that can freely rotate around the center is attached to each of the flange coupling bases, one end of each wire is attached to the arc portion of each moment lever, and the other end of the wire receives a tensile force. Piping characterized by being connected to heavy metal fittings, the wire between the moment lever and the loading metal fitting being kept at a right angle to the direction connecting the fulcrums of both moment levers, and both wires being arranged in parallel Elbow out-of-plane bending test equipment.