JP2005147690A - High pressure cycle testing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure cycle testing device capable of suppressing facility cost, and shortening a test time. <P>SOLUTION: This high pressure cycle testing device 1 is equipped with a specimen support means 2 for supporting inside a specimen S having a gas passage 14 open to the outside and having a front end opening and a rear end opening, a cylindrical cylinder 3 having on the front end an opening open to the gas passage 14 of the specimen support means 2, a piston 4 having a packing part 5 slide-contacted to the cylinder 3 and movable forward and backward, a servomotor 6 for moving the piston 4, a gas supply means 7 for supplying gas to the front part inside the cylinder 3, and a sensor means 8 for detecting the pressure inside the gas passage 14 of the specimen support means 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-pressure cycle test apparatus, and more particularly to a high-pressure cycle test apparatus that applies a required cycle load to a specimen such as a pipe or a valve to test durability.

  Conventionally, in a cycle test of materials and equipment in high-pressure gas and the like, as shown in FIG. 3, a compressor (52), an accumulator (53), a first control valve (54), a second control valve (55) and Produce a test device (51) equipped with a sensor (56), and send high-pressure gas to the specimen (S) via an external compressor (52), accumulator vessel (53), control valve (54), etc. In general, a cycle load is applied.

  In the conventional high-pressure cycle test apparatus shown in FIG. 3, as the pressure increases, the equipment cost for the high-pressure cycle test apparatus becomes enormous, the amount of gas used is large, and the running cost is high. In addition, the burden for gas recovery also increases. In addition, in order to avoid temperature expansion due to adiabatic compression accompanying high pressure introduction, it is necessary to introduce gas slowly, so that there is a problem that it takes a long test time.

  It is an object of the present invention to provide a high-pressure cycle test apparatus that can reduce the equipment cost and shorten the test time.

  The high-pressure cycle test apparatus according to the present invention has a gas passage leading to the outside and a specimen support means for internally supporting a specimen having an opening at one end and an opening at the other end, and a gas passage of the specimen support means at one end. A cylindrical cylinder having an opening; a piston having a packing portion that is in sliding contact with the cylinder; movable in the cylinder length direction; drive means for moving the piston; and gas supply means for supplying gas into the cylinder. It is characterized by being.

  The specimen is usually a piping device such as a pipe and a valve constituting the fluid control apparatus, and the durability of the new material and the new structure is evaluated.

  As the driving means for moving the piston, for example, a hydraulic servo motor is used, and the piston is reciprocated in a predetermined cycle by hydraulic pressure. The gas supply means supplies gas for setting an initial pressure before moving the piston. The cylinder is first set to a constant pressure by the gas supply means, and the pressure is increased by the advance of the piston. When the piston is stopped at a predetermined position, a constant high pressure is maintained, and when the piston is retracted, the pressure is lowered, thereby applying a required cycle load to the specimen.

  The specimen support means includes, for example, a fixed holding part having a holding surface against which one end opening of the specimen is pressed, and a movable holding part having a holding surface pressed against the other end opening of the specimen and movable. The gas passage is provided in a penetrating manner in the fixed holding portion so as to communicate with the test space of the specimen. In this way, the specimen can be held fluid-tight by setting the movable holder after the specimen is held by the fixed holder, so that preparation work for the test can be easily performed. it can. The shapes of the fixed holding portion and the movable holding portion are changed according to the shape of the specimen. Further, the specimen support means preferably further has a cylindrical cover part that is detachably secured between the fixed holding part and the movable holding part, thereby protecting the specimen. It is possible to apply pressure between the specimen and the cover.

  The gas supply means preferably comprises a gas introduction pipe that leads to a gas source, and an on-off valve and a check valve provided in the middle of the gas introduction pipe. If it does in this way, the gas lost by the leak during a test will be replenished via a check valve, and test conditions will be kept constant.

  The specimen support means is, for example, a cylindrical concave concentric with the opening of the specimen on each holding surface of the fixed holding section and the movable holding section so as to be suitable for giving a high-pressure cycle load to the inside of the tube. And a short cylindrical protrusion, a cylindrical inner seal that is closely fitted in the opening of the specimen is closely fitted in the recess, and a protrusion of the specimen is fitted in the protrusion. A cylindrical outer seal that is closely fitted to the outer peripheral edge of the opening is closely fitted, and a communication passage that connects the gas passage of the fixed holding portion and the test space of the specimen to the inner seal of the fixed holding portion. Is provided in a penetrating manner.

  According to the high-pressure cycle test apparatus of the present invention, by directly connecting the specimen support means and the cylinder, a high pressure is generated in the minimum necessary specimen support means and the cylinder, and the gas sealed in the cylinder is reciprocated by the piston. Since a cycle load is generated, the risk of high-pressure equipment is reduced, gas is not discharged, and running costs are reduced. Further, by using a hydraulic servo motor and a cylinder instead of the compressor and the pressure accumulating vessel, a compact facility can be obtained, and manufacturing at low cost is possible. In addition, free pressure creation is possible and there is no temperature rise due to adiabatic compression, etc., so the time for boosting can be shortened, thereby shortening the cycle time and enabling stable testing It becomes.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, the left side of the figure is the front and the right side is the back.

  1 and 2 show an embodiment when the high-pressure cycle test apparatus of the present invention is applied to a test of a cylindrical specimen such as a tube.

  The high-pressure cycle testing apparatus (1) includes a specimen support means (2) having a gas passage (14) communicating with the outside and supporting a specimen (S) having a front end opening and a rear end opening inside, and a front end. A cylindrical cylinder (3) having an opening communicating with the rear end opening of the gas passage (14) of the specimen support means (2) and closed at the rear end, and a packing portion (5) in sliding contact with the cylinder (3) It has a piston (4) that can move back and forth (cylinder length direction), a servo motor (6) as a driving means for moving the piston (4), and a gas that supplies gas to the front part of the cylinder (3) Supply means (7) and sensor means (8) for detecting the pressure in the gas passage (14) of the specimen support means (2) are provided.

  The specimen support means (2) includes a rectangular parallelepiped block-shaped fixing holder (11) having a holding surface against which the rear end opening of the specimen (S) is pressed, and the specimen (S). The movable holding part (12) having a rectangular parallelepiped block shape that has a holding surface pressed against the front end opening of the movable body, and is detachably passed between the fixed holding part (11) and the movable holding part (12). It consists of a cylindrical cover part (13). The gas passage (14) is provided in a penetrating manner in the fixed holding portion (11) so as to communicate with an internal space that is a test space of the cylindrical specimen (S).

  The servo motor (6) reciprocates the piston (4) in a predetermined cycle by hydraulic pressure, and it can be a triangular wave, trapezoidal wave, pulse wave, etc. as a pressure waveform, and various times can be set for one cycle. It is possible.

  The gas supply means (7) performs initial filling of the gas in the front space in the cylinder (3) and automatically replenishes the gas lost due to leakage, and includes a gas introduction pipe (27) leading to a gas source, It consists of an on-off valve (28) and a check valve (29) provided in the middle of this.

  As shown in detail in FIG. 2, the holding surface of the fixed holding portion (11) is larger than the cylindrical recess (15) and the recess (15) concentric with the rear end opening of the specimen (S). A short cylindrical protrusion (16) having a diameter is provided. In the recess (15), the rear part of the cylindrical inner seal (17) whose front part is closely fitted into the inner diameter of the specimen (S) is closely fitted. The rear part of the cylindrical outer seal (18) whose front part is closely fitted into the outer diameter of the specimen (S) is closely fitted into the protrusion (16). The inner seal (17) is provided with a communication passage (17a) penetrating the gas passage (14) of the fixed holding portion (11) and the internal space of the specimen (S). Similarly, the holding surface of the movable holding portion (12) has a cylindrical recess (19) concentric with the front end opening of the specimen (S) and a short cylindrical shape having a larger diameter than the recess (19). A protrusion (20) is provided. In the recess (19), the front part of the cylindrical inner seal (21) whose rear part is closely fitted into the inner diameter of the specimen (S) is closely fitted. A front part of a cylindrical outer seal (21) whose rear part is closely fitted into the outer diameter of the specimen (S) is closely fitted into the projecting part (20). The inner seal (21) has the same shape as the inner seal (17) provided on the holding surface side of the fixed holding portion (11), and a penetrating communication path (21a) is formed.

  The rear end of the cylinder (3) is closed by a closing block (23), and the intermediate part of the piston (4) is inserted through a through hole (23a) provided in the closing block (23) so as to be movable back and forth. ing. The closing block (23) is provided with a seal (24) for sealing between the piston (4) and the edge of the through hole (23a). The front end of the cylinder (3) is fluid-tightly fixed to the fixed holding portion (11) by welding or the like.

  The packing portion (5) includes a plurality of sets of seal rings (25) sequentially fitted on the small diameter portion at the front end of the piston, and a fixing ring (26) that prevents the seal ring (25) from coming off.

  According to the high-pressure cycle test apparatus (1), the cylinder (3) is first brought to a constant pressure by the gas supply means (7). Then, the pressure is increased by moving the piston (4) forward, the piston (4) is stopped at a predetermined position, a constant high pressure is maintained, and the pressure is decreased by moving the piston (4) backward. The required cycle load is applied to the specimen (S). Gas lost due to leakage during the test is replenished via the check valve (29) and the test conditions are kept constant throughout the test.

  In the above embodiment, an example in which a load is applied to the inside of the tube (S) as a specimen has been described, but by slightly changing the shapes of the fixed holding portion (11) and the movable holding portion (12), the tube It is also possible to apply a load outside (S). In this case, the cover part (13) is a container for applying pressure between the specimen (S) and the cover part (13). Further, the specimen can be a fluid control device such as a valve by changing the shapes of the fixed holding portion and the movable holding portion.

1 is a side view showing an embodiment of a high-pressure cycle test apparatus according to the present invention. It is an expanded longitudinal cross-sectional view of the principal part. It is a side view which shows the conventional high-pressure cycle test apparatus which the high-pressure cycle test apparatus by this invention makes object.

Explanation of symbols

(1) High pressure cycle test equipment
(2) Specimen support means
(3) Cylinder
(4) Piston
(5) Packing part
(6) Servo motor (drive means)
(7) Gas supply means
(11) Fixed holding part
(12) Movable holding part
(14) Gas passage
(15) Recess
(16) Projection
(17) Inner seal
(17a) Communication passage
(18) Outer seal
(27) Gas introduction pipe
(28) On-off valve
(29) Check valve
(S) Specimen

Claims (4)

  A specimen support means for internally supporting a specimen having a gas passage leading to the outside and having an opening at one end and an opening at the other end, a cylindrical cylinder having an opening leading to the gas passage of the specimen support means at one end, and a cylinder A high-pressure cycle test comprising a piston that has a packing portion that is in sliding contact with the cylinder, is movable in the cylinder length direction, a drive unit that moves the piston, and a gas supply unit that supplies gas into the cylinder. apparatus.   The specimen support means includes a fixed holding part having a holding surface against which one end opening of the specimen is pressed, and a movable holding part having a holding surface pressed against the other end opening of the specimen, and movable. 2. The high-pressure cycle testing apparatus according to claim 1, wherein the passage is provided in a penetrating manner in the fixed holding portion so as to communicate with the test space of the specimen.   The high-pressure cycle testing apparatus according to claim 1 or 2, wherein the gas supply means includes a gas introduction pipe communicating with a gas source, and an on-off valve and a check valve provided in the middle thereof.   Each holding surface of the fixed holding part and the movable holding part is provided with a cylindrical recess and a short cylindrical protrusion that are concentric with the opening of the specimen. A cylindrical inner seal that is tightly fitted into the outer periphery of the specimen is tightly fitted, and a cylindrical outer seal that is tightly fitted into the outer periphery of the opening of the specimen is tightly fitted into the protrusion, 3. The high-pressure cycle test apparatus according to claim 2, wherein a communication passage that communicates the gas passage of the fixed holding portion and the test space of the specimen is provided in the inner seal of the fixed holding portion in a penetrating manner.

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