JPH0656755U - Testing equipment for metal fatigue testing - Google Patents

Abstract

(57) [Summary] [Purpose] Metal fatigue tests are conducted in a corrosive environment such as crude oil and hydrogen sulfide gas, and the surrounding environment is not contaminated. [Structure] Two rods 1 whose other ends are respectively connected to the vibrator 15 and the frame 11 with the metal fatigue test piece T as the middle.
Capsule 2 in which 2 and 12 and a tubular body 21 surrounding the test piece are hermetically sealed with a rubber lid 22 fitted to the intermediate portion of the rod 12.
And a gas nozzle 31 for supplying liquid and gas into the capsule 2, a liquid nozzle 32, and an exhaust pipe 33 for guiding exhaust gas from the capsule to the gas treatment facility 6.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a metal fatigue test apparatus for fatigue testing a metal test piece such as a steel material in a special environment such as corrosiveness.

[0002]

[Prior art]

 Conventionally, as a fatigue test of a metal test piece such as a steel material, a fatigue test in the air in the room or a fatigue test in water or artificial seawater has been performed. Naturally, the fatigue test in the air in the room is an open test, and the fatigue test in one-way water or artificial seawater is performed with the test piece immersed in the water tank. Water of specified components and temperature or artificial seawater is continuously supplied, but these waters do not affect the surrounding environment unless they leak out of the system.

However, steel materials and other metal materials used for oil drilling equipment and crude oil tankers are exposed to the hydrogen sulfide gas atmosphere contained in crude oil, which causes the metals to corrode or hydrogen embrittlement. It is known to cause fatigue failure in the environment, and it is necessary to reproduce such a corrosive environment and perform a fatigue test in that environment. However, in conventional open-air laboratory tests, it is not possible to continuously supply toxic hydrogen sulfide gas to the test piece, and even in a test device equipped with a water tank, hydrogen sulfide gas is continuously supplied. If it is supplied to the test piece part, the gas just supplied is discharged from the water tank, so it is necessary to collect and process it.

[0004]

[Problems to be solved by the device]

 The present invention realizes a special environment such as corrosiveness, and safely treats the generated exhaust gas so as not to adversely affect the surrounding environment. The purpose is to realize a fatigue testing device.

[0005]

Means for Solving the Problems The present invention includes two rods arranged in a straight line, the other end of which is connected to a vibration exciter and a fixed end with a metal fatigue test piece as an intermediate. A capsule in which both ends of a tubular body surrounding the metal fatigue test piece part are sealed with lids of a flexible material fitted in the intermediate parts of the two rods, and liquid and gas are supplied into the capsule. A metal fatigue test apparatus comprising a liquid supply means, a gas supply means, and an exhaust means for guiding the exhaust gas from the capsule to a gas treatment device, and preferably, the capsule is further surrounded by a cover body. A test device for a metal fatigue test, comprising: an air supply means for continuously supplying clean air into the cover body; and an exhaust means for guiding exhaust gas from the inside of the cover body to a gas treatment device. .

[0006]

[Work]

 In the present invention, the test piece is housed in a capsule formed by sealing both ends of a cylindrical body with a lid made of a flexible material fitted in the middle part of two rods holding the test piece. A corrosive liquid or gas was supplied to the test pieces so that the test pieces were immersed in them. The two rods are arranged in a straight line with the metal fatigue test piece in the middle and the other ends connected to the vibrator and the fixed end, respectively, and the distance between the two rods changes with a constant period. Therefore, if the lid of the capsule is made of a material that is not a flexible material such as ordinary metal or resin, it is difficult to seal the gas in this portion because the rod repeats sliding at the portion that penetrates the lid. However, in the test apparatus of the present invention, due to the above-mentioned configuration, even if the rod reciprocates, the capsule lid itself follows due to bending, so that a gap may be created between the rod and the lid. None, the gas inside is completely sealed and does not leak to the surroundings.

[0007]

【Example】

 An embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a front view of a compact type fatigue tensile test piece T according to the ASTM standard used in this example. This test piece is made by cutting a thick steel plate with a plate thickness of 10 to 12.5 mm into a rectangular shape, and making a notch with a saw in the upper center to make a U shape. The tip of the U shape is 2 mm long by electric discharge machining and the tip radius is A 0.1 mm notch is made, and pin holes are provided on both sides of the notch for connecting to a pull rod that bears a load. A strain gauge G may be attached to the position directly under the notch to measure the crack length from the strain due to stress.

FIG. 1 is an overall configuration diagram of the test apparatus. 1 is a test apparatus main body, 2 is a part of the capsule, T is a test piece, 4 is a control device, 5 is a gas supply unit, and 6 is a gas. It is a processing device. The capsule 2 is supported in the center of the test apparatus body 1 via the pull rod 12. The two pull rods 12 and 12 are aligned on a straight line which is connected to the vibrator 15 and the frame 11 of the test apparatus body 1 which is the fixed end with the test piece T in the capsule 2 as the middle. It is arranged. The shaker 15 is a hydraulic cylinder operated by a servo valve 16 and is connected to a hydraulic unit 17 composed of a hydraulic pump and the like, and the servo valve 16 is controlled by the controller 4.

Hydrogen sulfide gas is supplied into the capsule 2 from a gas supply unit 5 equipped with a gas cylinder, a switching valve, a pressure regulator, a pressure gauge and the like through a gas nozzle 31. Further, the crude oil is injected into the capsule by the liquid nozzle 32, and the test piece is dipped and exposed in these gas and liquid. On the other hand, the gas inside is discharged from the capsule 2 through the primary exhaust pipe 33, and is guided to the gas processing device 6 and processed. For the treatment of exhaust gas containing a large amount of hydrogen sulfide gas, an aqueous solution of sodium hydroxide (caustic soda) is suitable.

As will be described later, the capsule 2 of the present embodiment has no internal gas leakage as a basic structure, but the various nozzles described above and the vinyl hoses connected to these nozzles are in and out. No gas leaks from the connection, etc., but should not pollute the environment should the capsule be damaged. Therefore, the capsule 2 of this embodiment is further surrounded by a cover body. The cover body is constructed by attaching transparent resin side covers 14, 14 on both sides of a rectangular metal frame of the frame 11 of the test apparatus main body 1. The non-drying sealant is applied to the entire surface of the side cover 14 which is attached. An air supply port 34 through which clean air such as compressed air is blown inside is provided in a part of the cover body, and the exhaust gas from the inside of the cover body is also exhausted from the inside of the cover body by the secondary exhaust port 35. Be led to.

FIG. 2 is a partial sectional view of the capsule 2. The two pull rods 12, 12 are connected to the test piece T in the capsule 2 by a pin 13, and the other end of each pull rod 12 is a vibrator 15 and a fixed end of the test apparatus main body 1, respectively. It is connected in a straight line to the frame 11 via a universal joint or the like, and a load is repeatedly applied in the direction of the arrow. The capsule 2 has a structure in which both end surfaces of a cylindrical casing 21 are sealed by rubber disk-shaped end covers 22. The casing 21 is made of a transparent resin so that the inside can be observed. On the upper part, the gas nozzle 31, the liquid nozzle 32, the primary exhaust pipe 33, and a lead wire outlet 36 from the strain gauge G are provided. The bottom is provided with a drainage port 37 used when draining the internal liquid.

As described above, the edge portions of the rubber disk-shaped end cover 22 are fixed to both end surfaces of the casing 21 by the ring nuts 23 via the gaskets 24. Therefore, both ends of the casing 21 and the inner surface of the ring nut 23 are threaded. The center portion of the end cover 22 has an increased thickness as shown in FIG. 2, is fitted to the stepped portion of the pull rod 12, and is tightened with a nut 27. When tightening the nut 27, insert the washer 26 to avoid friction with the surface of the end cover 22, and do not overtighten the nut 27 so that the center part of the end cover 22 does not swell out in the diameter direction and cause gas leakage. It is fastened with a hose band 25 etc.

FIG. 3 is a cross-sectional view of the test apparatus main body 1 taken in a direction perpendicular to the test piece, showing the arrangement of the gas nozzles 31 and the liquid nozzles 32 in the capsule 2, and the test apparatus main body. A state in which a cover body is formed by the frame 11 of the body 1 and side covers 14 and 14 made of transparent resin on both surfaces and surrounds the capsule 2 is shown. In the above description, the fatigue test was performed on a metallic material in an atmosphere of crude oil and hydrogen sulfide gas.However, the test device of the present invention is not limited to this example, and any liquid or in a special environment such as a gas atmosphere can be used. It goes without saying that it can also be applied to fatigue tests in. Further, even if the shape or the mounting method of the test piece is different, it can be easily dealt with by changing the end portion of the pull rod 12.

[0014]

[Effect of device]

 According to the present invention, a special environment in which crude oil and hydrogen sulfide gas coexist can be realized in a capsule to perform a fatigue test, and a toxic gas is hermetically sealed in the device so that leakage is completely captured. Since gas treatment is performed by using the gas treatment, it has excellent effects such as not deteriorating the surrounding environment.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view of the capsule part of the present invention.

FIG. 3 is a partial cross-sectional view of the main body of the test apparatus of the present invention.

FIG. 4 is a front view of a test piece used in the present invention.

[Explanation of symbols]

 1 Main body of test equipment 11 Frame 12 Pull rod 13 Pin 14 Side cover 15 Vibrator 16 Servo valve 17 Hydraulic unit 2 Capsule 21 Casing 22 End cover 23 Ring nut 24 Gasket 25 Hose band 26 Washer 27 Nut 31 Gas nozzle 32 Liquid nozzle 33 Primary exhaust pipe 34 Air supply port 35 Secondary exhaust port 36 Lead wire outlet 37 Drainage port 4 Control device 5 Gas supply unit 6 Gas treatment device T Specimen G Strain gauge

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Kosuke Takanashi 1st Kawasaki-cho, Chuo-ku, Chiba, Chiba Prefecture Technical Research Division, Kawasaki Steel Co., Ltd. (72) Mitsuo Shiratori 1st Kawasaki-cho, Chuo-ku, Chiba-shi Kawasaki Steel Corporation Technical Research Division

Claims (2)

[Scope of utility model registration request] 1. Two rods (12) arranged in a straight line, the other end of which is connected to the vibrator (15) and the fixed end with the metal fatigue test piece (T) as the middle, and A capsule formed by sealing both ends of a tubular body (21) surrounding a metal fatigue test piece (T) with a flexible material lid (22) inserted into an intermediate portion of the two rods (12) ( 2), liquid supply means (32) for supplying liquid and gas into the capsule (2), gas supply means (5, 31), and exhaust gas from the capsule (2) to the gas treatment device (6). A testing device for a metal fatigue test, comprising: a leading exhaust means (33). 2. A capsule body (2) is further covered with a cover body (11,
An air supply means (34) that is surrounded by 14) and continuously supplies clean air to the inside of the cover body, and an exhaust means (35) that guides exhaust gas from the inside of the cover body to the gas treatment device (6). The test apparatus for fatigue testing of metals according to claim 1, comprising: