JPH0625719B2 - Alternating fatigue testing machine - Google Patents
Alternating fatigue testing machineInfo
- Publication number
- JPH0625719B2 JPH0625719B2 JP60074917A JP7491785A JPH0625719B2 JP H0625719 B2 JPH0625719 B2 JP H0625719B2 JP 60074917 A JP60074917 A JP 60074917A JP 7491785 A JP7491785 A JP 7491785A JP H0625719 B2 JPH0625719 B2 JP H0625719B2
- Authority
- JP
- Japan
- Prior art keywords
- plunger
- piston
- container
- test piece
- pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/32—Investigating strength properties of solid materials by application of mechanical stress by applying repeated or pulsating forces
- G01N3/36—Investigating strength properties of solid materials by application of mechanical stress by applying repeated or pulsating forces generated by pneumatic or hydraulic means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/003—Generation of the force
- G01N2203/0042—Pneumatic or hydraulic means
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- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は容器状試験体の内外に交番して高圧を負荷する
交番疲労試験機に関する。[Field of Industrial Application] The present invention relates to an alternating fatigue tester that alternately applies pressure inside and outside a container-shaped test body to apply a high pressure.
組み合わせ応力下における試験片の変形や疲労強度など
を調べる試験機は、第３図に示されるように、略中空円
筒形状の試験片１の両端が取り付けボルト２により試験
機本体フレーム３に固定されている固定軸であるロード
セル４と負荷軸６に固定され、図示しないリニアアクチ
ユエータおよびロータリアクチユエータによつて負荷軸
６を介し、符号Ａ，Ｂでそれぞれ示される軸方向荷重，
ねじり荷重が試験片１に加えられるようになつている。
この第３図に示す試験機はフラクチヤー１９７７，ボリ
ユーム２，アイ・シー・エフ４（Fracture 1977, Vol
・２，ICF ４）第1161〜第１１６８頁の中に示されてい
る。As shown in FIG. 3, the tester for examining the deformation and fatigue strength of the test piece under the combined stress is fixed to the tester main body frame 3 by the mounting bolts 2 at both ends of the substantially hollow cylindrical test piece 1. Is fixed to the load cell 4 and the load shaft 6 which are fixed shafts, and the axial load indicated by the reference signs A and B, respectively, via the load shaft 6 by a linear actuator and a rotary reactor (not shown),
A torsion load is applied to the test piece 1.
The test machine shown in FIG. 3 is a Fracture 1977, Vol.
-2, ICF 4) As shown in pages 1161 to 1168.
しかし、前記従来の試験機では、試験片１に作用する力
は、第３図矢印Ａに示す軸方向力と、第３図矢印Ｂに示
すねじり荷重だけであり、そのため試験片１の断面内に
は第４図斜線で示す第II象限又はIV象限の応力状態しか
得ることができず、第Ｉ、第III象限における応力状態
を得ることはできなかつた。However, in the conventional tester, the forces acting on the test piece 1 are only the axial force shown by the arrow A in FIG. 3 and the torsional load shown by the arrow B in FIG. In Fig. 4, only the stress states in the quadrants II or IV shown by diagonal lines in Fig. 4 can be obtained, and the stress states in the quadrants I and III cannot be obtained.
また、前記した文献の中には、円筒形状試験片１内の内
圧を高めるようにして、第４図における第Ｉ象限および
第III象限の応力状態をも達成できるようにした試験機
もある旨の記載があるが、その詳細は開示されていな
い。Further, some of the above-mentioned documents include a tester that can increase the internal pressure in the cylindrical test piece 1 to achieve the stress states in the quadrants I and III in FIG. However, the details are not disclosed.
そこで、発明者らの考察によると、円筒形状試験片１内
の内圧を高める構造としては、第５図に示されるよう
に、負荷軸６に試験片１の内部に延びる流体通路９を穿
設し、ポンプなどの流体加圧源からこの通路９を介して
試験片１内に高圧流体を供給することにより試験片１の
内圧を高め、第Ｉ象限の応力状態を得るようにした構造
を考えることができる。そして試験片１の疲労強度を調
べるには、試験片１内への加圧流体供給路にサーボ弁を
設け、一定周期で試験片１の内圧を高めるようにするこ
とにより行うことができる。Therefore, according to the consideration of the inventors, as a structure for increasing the internal pressure in the cylindrical test piece 1, as shown in FIG. 5, the load shaft 6 is provided with a fluid passage 9 extending inside the test piece 1. Then, consider a structure in which the internal pressure of the test piece 1 is increased by supplying a high-pressure fluid into the test piece 1 through the passage 9 from a fluid pressure source such as a pump, and a stress state in the quadrant I is obtained. be able to. The fatigue strength of the test piece 1 can be examined by providing a servo valve in the pressurized fluid supply path into the test piece 1 and increasing the internal pressure of the test piece 1 at a constant cycle.
しかし、ポンプなどの流体加圧源からの加圧流体をサー
ボ弁を介して試験片１内に供給する構造の試験機では、
試験片１の内圧を１０〜２００kg／cm2の範囲でしか高
めることができず、試験できる試験片の応力状態の範囲
が限られたものとなつていた。However, in a tester having a structure in which a pressurized fluid from a fluid pressure source such as a pump is supplied into the test piece 1 via a servo valve,
The internal pressure of the test piece 1 could be increased only in the range of 10 to 200 kg / cm 2 , and the range of stress states of the test piece that could be tested was limited.
本発明は前記問題点に鑑みなされたもので、その目的
は、試験片に交番して作用する応力の大きさおよび応力
作用方向を広く制御することのできる交番疲労試験機を
提供することにある。The present invention has been made in view of the above problems, and an object thereof is to provide an alternating fatigue tester capable of widely controlling the magnitude of stress and the acting direction of stress acting in alternation on a test piece. .
本発明に係る交番疲労試験機は、密閉容器内に容器状試
験体を配置し、サーボ弁により駆動されるピストンと、
このピストンのそれぞれの端面に連設されたプランジヤ
とよりなるピストン−プランジヤシリンダ装置を備えた
交番疲労試験機において、それぞれのプランジヤを所定
断面積を有する小径プランジヤで形成し、それぞれの小
径プランジヤをそれぞれのプランジヤ摺動室内で一体に
反復摺動させ、一方のプランジヤ摺動室を密閉容器内に
連通させるとともに、他方のプランジヤ摺動室を容器状
試験体内に連通させ、容器状試験体内外に交番して高圧
流体を供給するそれぞれの配置に、容器状試験体の内外
圧を調整する逃し弁を設けた構成とする。The alternating fatigue tester according to the present invention has a container-shaped test body arranged in a closed container, and a piston driven by a servo valve,
In an alternating fatigue tester equipped with a piston-plunger cylinder device consisting of a plunger continuously connected to each end surface of this piston, each plunger is formed by a small diameter plunger having a predetermined cross-sectional area, and each small diameter plunger is formed. Repeatedly sliding in the plunger slide chamber of one unit, one of the plunger slide chambers is in communication with the closed container, and the other plunger slide chamber is in communication with the container-like test body, and is alternated inside and outside the container-like test body. Then, a relief valve for adjusting the internal and external pressures of the container-shaped test body is provided in each arrangement for supplying the high-pressure fluid.
本発明によれば、比較的低い圧力によつてピストンを駆
動させ、このピストンの駆動によりピストン径に比べ小
径のプランジヤが駆動し、容器状構造の試験体内外へ交
番して高圧流体が供給されることになる。According to the present invention, a piston is driven by a relatively low pressure, and a plunger having a diameter smaller than the piston diameter is driven by the driving of the piston, and a high pressure fluid is alternately supplied to the inside and outside of the test body of the container-shaped structure. Will be.
次に、本発明の実施例を図面に基づいて説明する。 Next, an embodiment of the present invention will be described with reference to the drawings.
第１図は本発明に係る交番疲労試験機の要部を示す図で
あり、略中空円筒形状の試験片１の両端はボルト１２に
よつて固定軸であるロードセル14と負荷軸１６に固定さ
れている。試験片１は、カプセル１８で密閉された構造
となつており、このカプセル１８の一端は、ロードセル
１４にボルト１２Ａによつて固定され、他端は負荷軸１
６と相対回動可能となつている。固定軸１４には試験片
１の内部に延びる流体通路９が穿設され、一方カプセル
１８には、カプセル内に延びる流体通路16が穿設されて
おり、これらの流体通路９，１６を介して試験片１の内
部１Ａおよび外部１Ｂにピストン−プランジヤシリンダ
装置２０から加圧流体が交互に供給されるようになつて
いる。FIG. 1 is a view showing a main part of an alternating fatigue tester according to the present invention. Both ends of a substantially hollow cylindrical test piece 1 are fixed to a load cell 14 and a load shaft 16 which are fixed shafts by bolts 12. ing. The test piece 1 has a structure in which it is sealed with a capsule 18. One end of the capsule 18 is fixed to the load cell 14 with a bolt 12A, and the other end is the load shaft 1.
It is possible to rotate relative to 6. The fixed shaft 14 is provided with a fluid passage 9 extending into the inside of the test piece 1, while the capsule 18 is provided with a fluid passage 16 extending into the capsule. The pressurized fluid is alternately supplied from the piston-plunger cylinder device 20 to the inside 1A and the outside 1B of the test piece 1.
ピストン−プランジヤシリンダ装置２０は、シリンダ２
２内にピストン２４が配設され、このピストン２４は摺
動方向前後に突出するプランジヤ（小径プランジヤ）２
５Ａ，２５Ｂを有しており、シリンダ２２に設けられた
サーボ弁２７によつてシリンダ２２内に加圧流体が供給
され、これによつてピストン２４とプランジヤ２５Ａ，
２５Ｂが一体に矢印Ｃ方向に反復摺動するようになつて
いる。シリンダ装置２０のプランジヤ摺動室２６Ａは、
配管２８を介してカプセル１８に穿設された流体通路１
６に接続され、一方、プランジヤ摺動室２６Ｂは、配管
３０を介して負荷軸１６に穿設された流体通路９に接続
されている。このためプランジヤ２５Ａ，２５Ｂによつ
て加圧された加圧流体が試験片１の内部１Ａおよび外部
１Ｂに交番して作用するようになつている。なおサーボ
弁２７の弁駆動部には図示しない制御装置からピストン
２４の振幅が正弦波状となる制御信号が出力されてお
り、これにより試験片１の内外に高圧が正弦波状に交番
して作用するようになつている。The piston-plunger cylinder device 20 includes a cylinder 2
2. A piston 24 is provided in the piston 2, and the piston 24 is a plunger (small-diameter plunger) that projects forward and backward in the sliding direction.
5A and 25B, pressurized fluid is supplied into the cylinder 22 by a servo valve 27 provided in the cylinder 22, whereby the piston 24 and the plunger 25A,
25B slides integrally in the direction of arrow C repeatedly. The plunger sliding chamber 26A of the cylinder device 20 is
Fluid passage 1 drilled in capsule 18 via pipe 28
6, while the plunger slide chamber 26B is connected via a pipe 30 to a fluid passage 9 bored in the load shaft 16. Therefore, the pressurized fluid pressurized by the plungers 25A and 25B alternately acts on the inside 1A and the outside 1B of the test piece 1. A control device (not shown) outputs a control signal that causes the amplitude of the piston 24 to be sinusoidal to the valve drive portion of the servo valve 27, whereby high pressure acts alternately inside and outside the test piece 1 in a sinusoidal manner. It is becoming like this.
いま、ピストン２４の受圧面積をＡ、ピストン２４に作
用するシリンダ内の圧力をＰＡとし、プランジヤ２５Ａ
（２５Ｂ）の横断面積をａとすると、試験片１の内
（外）に作用する圧力Ｐａは、パスカルの原理により となり、低い駆動油圧ＰＡで非常に高い試験圧ＰＡを発
生させることができる。Assuming that the pressure receiving area of the piston 24 is A and the pressure in the cylinder acting on the piston 24 is P A , the plunger 25A
Assuming that the cross-sectional area of (25B) is a, the pressure Pa acting on the inside (outside) of the test piece 1 is based on Pascal's principle. Next, it is possible to generate a very high test pressure P A at a low driving pressure P A.
また、ピストン２４の駆動は、サーボ弁２７から供給さ
れる低圧流体により行われ、試験片１の変形に伴つて高
圧流体の流量が変化するが、この高圧流体の微小変化流
量Ｑａは、シリンダ22内において となり、ピストンの受圧面積Ａは、プランジヤの横断面
積ａに比べて非常に大きいので、流量ＱＡは大きく、そ
れだけサーボ弁２７の弁開度制御が楽である。Further, the piston 24 is driven by the low-pressure fluid supplied from the servo valve 27, and the flow rate of the high-pressure fluid changes as the test piece 1 deforms. Within Since the pressure receiving area A of the piston is much larger than the cross-sectional area a of the plunger, the flow rate Q A is large, and the valve opening control of the servo valve 27 is easier accordingly.
試験片１の内外に交番して負荷する圧力は、サーボ弁２
７の弁開度により調整することができるが、シリンダ２
２内の圧力を基準とする圧力制御でピストン２４を駆動
させる場合には、配管２８側と配管３０側の２つの高圧
流体供給路における漏れ量の違いから、ピストン２４は
第１図左右方向のいずれか（漏れ量の大きい側）に偏向
する虞れがある。このような場合には、ピストン２４を
所定ストローク量だけ変位させる変位制御を行うことが
望ましい。The pressure applied alternately to the inside and outside of the test piece 1 is the servo valve 2
7 can be adjusted by the valve opening degree of the cylinder 2
When the piston 24 is driven by pressure control with the pressure inside 2 as a reference, the piston 24 moves in the left-right direction in FIG. 1 due to the difference in the amount of leakage in the two high-pressure fluid supply paths on the pipe 28 side and the pipe 30 side. There is a risk of deflection to either one (the side with the larger amount of leakage). In such a case, it is desirable to perform displacement control for displacing the piston 24 by a predetermined stroke amount.
試験片１に作用させる内圧と外圧の絶対値が異なる場合
（完全両振りでない場合）は、シリンダ装置２０のプラ
ンジヤ２５Ａと２５Ｂの横断面積を異ならしめるか、あ
るいは配管２８，３０の途中に逃し弁４０，４２をそれ
ぞれ設け、配管２８，３０内の圧力がそれぞれ所定値と
なるように逃し弁４０，４２の弁開度を調整し、試験片
１に任意の大きさの内外圧交番負荷を与えることができ
る。なお、第１図において符号３１はカプセル１８内の
密閉を確保するためのシールリングである。When the absolute values of the internal pressure and the external pressure applied to the test piece 1 are different (when not completely swinging), the cross-sectional areas of the plungers 25A and 25B of the cylinder device 20 are made different, or a relief valve is provided in the middle of the pipes 28, 30. 40 and 42 are provided respectively, and the valve openings of the relief valves 40 and 42 are adjusted so that the pressures in the pipes 28 and 30 respectively become predetermined values, and the test piece 1 is subjected to an alternating internal and external pressure load. be able to. In FIG. 1, reference numeral 31 is a seal ring for ensuring the hermetically sealed inside of the capsule 18.
このように本実施例ではピストン２４とプランジヤ２５
Ａ，２５Ｂの径の大きさを調節することで内外圧差１０
００kg／cm2以上の非常に高い交番応力を試験片１に使
用させることができる。Thus, in this embodiment, the piston 24 and the plunger 25 are
By adjusting the diameter of A and 25B, the pressure difference between the inside and outside is 10
A very high alternating stress of 00 kg / cm 2 or more can be applied to the test piece 1.
第２図は本発明の第２の実施例の要部断面図である。FIG. 2 is a sectional view of the essential parts of the second embodiment of the present invention.
本実施例では、カプセル５４と蓋５６とによつて構成さ
れるカプセル内に容器状構造体５１を配置するととも
に、ピストン−プランジヤシリンダ装置２０によつて容
器状構造体５１内外に交番圧を作用させるように構成さ
れている。前記実施例では図示されてはいないリニアア
クチユエータやロータリアクチユエータによつて矢印
Ａ，Ｂ方向に荷重を与えるようになつているが、本実施
例では、容器状構造体５１の内外圧のみを交番させて変
化させるようになつており、真空チヤンバなどの疲労強
度試験などに適切である。符号５７，５８は蓋５６に穿
設されたカプセル内部への流体送給用通路、符号６０は
試験容器蓋、符号６２は締付ボルトを示している。In the present embodiment, the container-shaped structure 51 is arranged in a capsule constituted by the capsule 54 and the lid 56, and the piston-plunger cylinder device 20 applies an alternating pressure to the inside and outside of the container-shaped structure 51. Is configured to let. In the above-described embodiment, a linear actuator or a rotary actuator (not shown) is used to apply a load in the directions of arrows A and B, but in the present embodiment, the internal and external pressures of the container-like structure 51 are applied. It is designed to be changed only by altering only one, which is suitable for fatigue strength tests such as vacuum chambers. Reference numerals 57 and 58 are passages for fluid supply to the inside of the capsule formed in the lid 56, reference numeral 60 is a test container lid, and reference numeral 62 is a fastening bolt.
その他は前記第１の実施例と同一であるため、同一の符
号を付すことによりその説明は省略する。Since the other points are the same as those in the first embodiment, the description thereof will be omitted by giving the same reference numerals.
以上の説明から明らかなように、本発明によれば第Ｉ〜
第IVの全象限における応力状態を形成することができる
とともに、所定の大きさの内外圧交番負荷を与えること
ができ、かつそれぞれの小径プランジヤが一体に反復摺
動するため高圧流体の出入がほぼ一定し、簡素な機構で
広い範囲での疲労試験を行うことができるという効果が
ある。As apparent from the above description, according to the present invention,
In addition to being able to form a stress state in all quadrants of IV, it is possible to apply a predetermined amount of alternating internal and external pressure loads, and since each small-diameter plunger slides repeatedly as a unit, high pressure fluid is almost in and out. There is an effect that a fatigue test can be performed in a wide range with a constant and simple mechanism.
第１図は本発明の第１の実施例の要部断面図、第２図は
本発明の第２の実施例の要部断面図、第３図は従来の交
番疲労試験機の要部断面図、第４図は第３図に示す従来
の装置で達成できる主応力空間を示す主応力空間図、第
５図は第３図に示す従来の装置の改良に係る交番疲労試
験機の要部縦断面図である。 １……円筒形状試験片，１４……固定軸， １６……負荷軸，１８……カプセル，２０……ピストン
−プランジヤシリンダ装置，２２……シリンダ，２４…
…ピストン，２５Ａ，２５Ｂ……プランジヤ，２６……
サーボ弁，４０，４２……逃し弁。FIG. 1 is a sectional view of the essential parts of a first embodiment of the present invention, FIG. 2 is a sectional view of the essential parts of a second embodiment of the present invention, and FIG. 3 is a sectional view of the essential parts of a conventional alternating fatigue testing machine. 4 and 5 are principal stress space diagrams showing a principal stress space that can be achieved by the conventional device shown in FIG. 3, and FIG. 5 is a main part of an alternating fatigue testing machine according to an improvement of the conventional device shown in FIG. FIG. 1 ... Cylindrical test piece, 14 ... Fixed shaft, 16 ... Load shaft, 18 ... Capsule, 20 ... Piston-plunger cylinder device, 22 ... Cylinder, 24 ...
... Piston, 25A, 25B ... Plunger, 26 ...
Servo valve, 40, 42 ... Relief valve.
Claims (1)
ボ弁により駆動されるピストンと、このピストンのそれ
ぞれの端面に連設されたプランジヤとよりなるピストン
−プランジヤシリンダ装置を備えた交番疲労試験機にお
いて、それぞれのプランジヤを所定断面積を有する小径
プランジヤで形成し、それぞれの小径プランジヤをそれ
ぞれのプランジヤ摺動室内で一体に反復摺動させ、一方
のプランジヤ摺動室を前記密閉容器内に連通させるとと
もに、他方のプランジヤ摺動室を前記容器状試験体内に
連通させ、該容器状試験体内外に交番して高圧流体を供
給するそれぞれの配管に、前記容器状試験体の内外圧を
調整する逃し弁を設けたことを特徴とする交番疲労試験
機。1. An alternation comprising a piston-plunger cylinder device in which a container-shaped test body is arranged in a closed container, and a piston driven by a servo valve and a plunger connected to each end surface of the piston are provided. In the fatigue tester, each plunger is formed by a small diameter plunger having a predetermined cross-sectional area, and each small diameter plunger is repeatedly slid integrally in each plunger sliding chamber, and one plunger sliding chamber is placed inside the closed container. And the other plunger slide chamber is communicated with the container-shaped test body, the inner and outer pressures of the container-shaped test body are alternately applied to the respective pipes that alternately supply the high-pressure fluid inside and outside the container-shaped test body. An alternating fatigue testing machine, which is equipped with a relief valve for adjustment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60074917A JPH0625719B2 (en) | 1985-04-09 | 1985-04-09 | Alternating fatigue testing machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60074917A JPH0625719B2 (en) | 1985-04-09 | 1985-04-09 | Alternating fatigue testing machine |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61233341A JPS61233341A (en) | 1986-10-17 |
| JPH0625719B2 true JPH0625719B2 (en) | 1994-04-06 |
Family
ID=13561211
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60074917A Expired - Lifetime JPH0625719B2 (en) | 1985-04-09 | 1985-04-09 | Alternating fatigue testing machine |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0625719B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2447668B (en) * | 2007-03-20 | 2012-02-08 | Verderg Ltd | Method and apparatus for pipe testing |
| JP5804469B2 (en) * | 2011-03-31 | 2015-11-04 | 学校法人立命館 | Multi-axis load test apparatus and method |
| CN103018107B (en) * | 2012-12-07 | 2016-06-08 | 潍柴动力股份有限公司 | A kind of high-pressure oil pipe fatigue rig |
| CN111881546B (en) * | 2020-06-12 | 2023-11-10 | 合肥通用机械研究院有限公司 | Pressure-bearing equipment test pressure calculation method based on differential pressure type fatigue test system |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2485114A1 (en) * | 1980-06-20 | 1981-12-24 | Framatome Sa | CENTRIFUGAL PUMP WITH REMOVABLE DIFFUSER |
-
1985
- 1985-04-09 JP JP60074917A patent/JPH0625719B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61233341A (en) | 1986-10-17 |
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