JP2005315736A - Apparatus for testing gas sealing performance and method for evaluating it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of testing the gas sealing performance of sealing members without being affected by temperature changes or pressure changes. <P>SOLUTION: A sealing member S1 for a ring-like gap is provided between a housing 11 and a shaft 12 to form two chambers (an A chamber and a B chamber) partitioned by the sealing member S1. After different gases are sealed in the A chamber and the B chamber and the shaft 12 is rotated for a prescribed time, the gases each sealed in the A chamber and the B chamber are analyzed by gas chromatography to evaluate the gas sealing performance of the sealing member S1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to, for example, a gas seal performance test apparatus and a gas seal performance evaluation method for testing a gas seal performance of a seal member provided in an annular gap between two members provided to be relatively movable. .

Conventionally, as a method of measuring the amount of gas movement in two spaces separated by a seal member, (1) the two spaces are set to a constant volume, and the volume of gas flowing in or out is measured with a flow meter. 2) A method is used in which two spaces are closed and the amount of gas movement is measured from a change in pressure. For example, Patent Document 1 describes a burette method, a pressurized standing method, a vacuum standing method, a helium leak detector, a soap film flow meter, and the like.
Japanese Patent Application Laid-Open No. 2001-066216

  By the way, in a seal member provided in the annular gap between the housing and the shaft, there are portions that slide with the housing and the shaft, and sliding heat is generated as the shaft moves, so the temperature in the vicinity of the seal member changes significantly. To do. For example, depending on the structure around the seal member and the axial speed, in the case of a radial lip seal, the temperature in the vicinity of the seal member may rise to about 100 to 150 ° C.

  In such a case, in the measurement methods (1) and (2), since the influence of gas expansion accompanying a temperature rise is large, there is a concern that the measurement becomes difficult and the accuracy is low.

  The present invention has been made in view of the circumstances as described above, and an object thereof is to provide a technique capable of testing the gas seal performance of a seal member without being affected by temperature change or pressure change. To do.

In order to achieve the above object, in the gas seal performance test apparatus according to the present invention,
Two members that are coaxially mounted relative to each other, and
By providing a test seal member in the annular gap between the two members, a first chamber and a second chamber separated by the test seal member;
Gas supply means for supplying different gases to the first chamber and the second chamber,
Driving means for relatively moving the two members;
In a state where a test seal member is provided in the annular gap and gas is supplied to the first chamber and the second chamber by the gas supply means, relative movement between the two members is performed by the drive means for a predetermined time. A gas outflow portion for allowing the gas enclosed in the first chamber and the second chamber to flow out of the first chamber and the second chamber, respectively, in order to analyze the gas sealed in the first chamber and the second chamber by gas chromatography. When,
It is characterized by providing.

  With this configuration, the amount of gas movement can be measured from the gas composition, and the gas seal performance can be tested without being affected by changes in temperature and pressure.

In the above configuration, the two members are configured by a housing having an opening on one end side in the axial direction and a bottom end on the other end side in the axial direction, and a shaft member inserted through the opening,
By providing the opening side seal member in the annular gap on the opening side than the position where the test seal member is provided,
A space that is separated from the test seal member provided in the annular gap and is formed on the bottom side of the housing from the test seal member is defined as the first chamber,
It is also preferable that a space formed by the test seal member and the opening side seal member provided in the annular gap is the second chamber.

Further, in the above configuration, a space that is separated from the opening side seal member provided in the annular gap and is formed on the opening side from the opening side seal member is defined as a third chamber.
In the housing, provided in each of the parts constituting the first chamber, the second chamber, and the third chamber, and provided with a gas introduction part for introducing the gas supplied by the gas supply means,
It is also preferable that the gas outflow portion is provided in each of the parts constituting the first chamber and the second chamber in the housing.

  Further, in the above configuration, the drive means for sealing the gas to be evaluated in the second chamber and sealing the gas different from the gas to be evaluated in the first chamber and performing analysis by gas chromatography When the two members are moved relative to each other, it is preferable that the gas to be evaluated is supplied to the third chamber by the gas supply means.

  Further, in the above configuration, the two members may be provided to be relatively rotatable, and the opening side seal member may be configured by a magnetic fluid seal.

In the above configuration, a gas chromatograph for analyzing the gas sealed in the first chamber and the second chamber;
A communication passage that communicates the gas chromatograph with the gas outflow portions of the first chamber and the second chamber;
It is also preferable to comprise.

In the gas seal performance evaluation method of the present invention,
By providing a seal member in an annular gap between two members that are coaxially and relatively assembled together, two chambers separated by the seal member are formed,
Gas sealing of the sealing member is performed by sealing the different gases in the two chambers and then relatively moving the two members for a predetermined time and then analyzing the gases sealed in the two chambers by gas chromatography. It is characterized by evaluating performance.

  By measuring the amount of gas movement from the gas composition by such a method, it becomes possible to evaluate the gas seal performance without being affected by temperature change or pressure change.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the technique which can test the gas-seal performance of a sealing member, without receiving to the influence of a temperature change or a pressure change.

  The best mode for carrying out the present invention will be exemplarily described in detail below with reference to the drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in this embodiment should be appropriately changed according to the configuration of the apparatus to which the invention is applied and various conditions. It is not intended to limit the scope to the following embodiments.

  FIG. 1 is a schematic diagram for explaining a configuration of a gas seal performance test apparatus 1 according to an embodiment of the present invention.

  The gas seal performance test apparatus 1 according to the present embodiment is roughly composed of an apparatus main body 10, a gas supply unit (gas supply means) 20, and a gas chromatograph unit 30.

  First, the apparatus main body 10 will be described.

The apparatus main body 10 includes a housing 11, a shaft 12 as a shaft member that is inserted through a shaft hole (opening) 11 a of the housing 11 and is rotatably provided to the housing 11, and a driving unit that rotationally drives the shaft 12. And a bearing 14 that rotatably supports the shaft 12 is provided. (In the following description, the portion composed of the housing 11 and the shaft 12 inserted through the shaft hole 11a of the housing 11 may be referred to as a test device head portion 15).
The housing 11 has a shaft hole 11a on one end side in the axial direction, and is provided with a bottomed shape (a container shape having only the shaft hole 11a as an opening) on the other end side in the axial direction. The tip end of the shaft 12 inserted through the shaft hole 11a is positioned closer to the shaft hole 11a than the bottom 11b of the housing 11.

  Two seal members are disposed in the annular gap between the housing 11 and the shaft 12. Here, the seal member provided on the bottom 11b side of the housing 11 is referred to as a seal member (test seal member) S1, and the seal member provided on the shaft hole 11a side is referred to as a seal member S2.

  By providing the seal members S1, S2 in the annular gap between the housing 11 and the shaft 12, three chambers (spaces) separated by the annular gap between the housing 11 and the shaft 12 and the seal members S1, S2. Will be formed. Here, a space formed on the bottom 11b side from the seal member S1 is a chamber A (first chamber), a space formed between the seal members S1 and S2 is a chamber B (second chamber), and a shaft hole is formed from the seal member S2. The space provided on the 11a side is referred to as C room (third room).

  The housing 11 communicates with the gas supply unit 20 and the A chamber, the B chamber, and the C chamber, and introduces gas from the gas supply unit 20 into the A chamber, the B chamber, and the C chamber, respectively. 11d and 11e are provided.

  Further, the housing 11 communicates with the gas chromatograph section 30 and the A and B chambers, respectively, and the gas that has flowed out (taken out, collected and released) from the A and B chambers. Gas outflow portions 11 f and 11 g for introducing (injecting) the gas into the gas inlet 30 are provided.

  Next, the gas supply unit 20 will be described.

  The gas supply unit 20 includes a gas cylinder (gas storage unit) 21 for storing gas, a gas flow rate control unit 22 for controlling the flow rate of gas flowing out from the gas cylinder 21, a gas flow rate control unit 22 and a gas introduction unit. A communication path 23 is provided for communicating between 11c, 11d, and 11e. Here, the communication paths communicating with the gas introduction portions 11c, 11d, and 11e in the communication path 23 are referred to as communication paths 23a, 23b, and 23c, respectively.

FIG. 1 shows a case where three gas cylinders 21 and three gas flow rate control units 22 respectively corresponding to the three gas cylinders 21 are provided. As shown in FIG. A communication passage 23 is connected from the gas flow rate control unit 22 via a valve 24.
a, 23b, and 23c can be communicated.

  Further, in the communication passages 23a and 23b, a valve 25 is also provided downstream (on the gas introduction portions 11c and 11d side) of the joining portion where the gases flowing out from the three gas flow rate control portions 22 join. And between the gas introduction parts 11c and 11d and the valve | bulb 25, the pressure gauge PI which detects the pressure of the gas in the communicating path 23 is provided, respectively.

  Next, the gas chromatograph unit 30 will be described.

  The gas chromatograph unit 30 includes a gas chromatograph 31, a gas sampler 32 for injecting a sample into the gas chromatograph 31, a carrier gas unit 33 containing a carrier gas introduced into the gas chromatograph 31, a detector 34, and an exhaust gas. A mouth 35 is provided.

  Further, a communication passage 36 is provided between the apparatus main body 10 and the gas chromatograph unit 30 to allow the gas outflow portions 11f and 11g of the housing 11 and the gas sampler 32 to communicate with each other.

  In the communication path 36, a valve 37, a needle valve 38, and a valve 39 are provided in order from the gas outflow portions 11f and 11g toward the gas sampler 32 side. When the valve 37 is opened, the gas in the A chamber and the B chamber of the housing 11 flows out to the gas chromatograph unit 30 side. The needle valve 38 is for adjusting the amount of gas in the A chamber and B chamber that flows into the gas chromatograph unit 30 side. The valve 39 switches the gas flow path whose flow rate is reduced by the needle valve 38 between the gas sampler 32 side and the exhaust port 35 side.

  In the gas seal performance test apparatus 1 configured as described above, the gas flow rate control unit 22 adjusts the gas flow rate supplied from the gas cylinder 21 and the needle valve 38 adjusts the gas outflow amount, thereby And the gas pressure in the B chamber can be controlled, and the gas seal performance test can be performed under a pressurized condition.

  Next, a test method for the gas seal performance test will be described.

  In the present embodiment, the seal member S1 shown in FIG. 1 is a seal member to be evaluated. Further, the seal members S1 and S2 are attached so that the B chamber side becomes the sealed side, and fluid such as oil and water can be sealed in the B chamber.

  The chamber A is replaced with a reference gas, and the chamber B is replaced with a gas to be sealed (test gas). That is, the reference gas is introduced into the A chamber and the test gas is introduced into the B chamber through the communication passages 23a and 23b and the gas introduction portions 11c and 11d from the gas cylinder 21 in which the reference gas and the test gas are respectively enclosed. The

  In this case, by adjusting the valve 24, a path connecting the gas cylinder 21 and the three chambers (A chamber, B chamber, C chamber) is set, and the valve 37 is closed and the valve 25 is opened. Then, the gas is sealed in the A and B chambers by controlling the gas flow rate by the gas flow rate control unit 22. In this case, each of the A chamber and the B chamber can be set to a desired gas pressure by detecting the pressure of the gas in the communication passage 23 with the pressure gauge PI.

Here, it is generally considered that the seal member sucks air from the atmosphere side to the oil tank side, and the seal member S2 is no exception, and some gas moves between the B chamber and the C chamber. It is thought that has occurred.

  Therefore, about 100 ml / min of the test gas is supplied to the C chamber from the gas cylinder 21 through the communication path 23c and the gas introduction part 11e. If it is not desirable that the test gas leaks, an inert gas such as nitrogen or argon may be supplied. Further, when there is no problem even if very little air is sucked into the B chamber, the gas may not be supplied. Further, a sealing member with extremely low suction performance may be used as the sealing member S2.

  Then, the shaft 12 is rotated with respect to the housing 11 by operating the motor 13. After the shaft 12 is rotated for a predetermined time, the valve 37 is opened so that the gas in the A chamber and the gas in the B chamber flow into the gas chromatograph unit 30.

  In the gas chromatograph unit 30, as described above, the gas sampler 32 injects the gas in the A chamber and the gas in the B chamber into the gas chromatograph 31. And the amount of gas movement from the A chamber to the B chamber and from the B chamber to the A chamber is measured.

  Next, more specific test (measurement) results will be described.

  An SC type oil seal (shaft diameter 50 mm, outer diameter 72 mm, height 12 mm) made of fluororubber was used as the seal member S1, and a seal member with extremely low oil suction performance was used as the seal member S2.

  Then, the A chamber, the B chamber, and the C chamber were formed by attaching these seal members S1 and S2 to the annular gap between the housing 11 and the shaft 12 of the apparatus main body 10 shown in FIG.

  By injecting oil (polyalphaolefin) into the formed B chamber, the oil was filled to the vicinity of the shaft center of the shaft 12 in the B chamber. Thereafter, chamber A was replaced with helium (He) gas and chamber B was replaced with nitrogen gas. Nitrogen gas was supplied to the C chamber at about 100 ml / min.

  The helium gas sucked by the seal member S1 (moved from the A chamber to the B chamber) by rotating the shaft 12 at a predetermined speed and analyzing (measuring) the helium gas concentration in the B chamber every predetermined time. The amount of was calculated.

  In the gas chromatography, argon was used as the carrier gas, the detector 34 was a thermal conductivity detector, and the column was molecular sieve 13X (manufactured by GL Sciences).

  FIG. 4 shows the measurement results of the gas seal performance test conducted using the gas seal performance test apparatus 1 shown in FIG. 1 under the above conditions.

  As shown in FIG. 4, in the gas seal performance test of the present embodiment, the test time and the amount of helium gas sucked are substantially proportional. Even when the shaft speed of the shaft 12 increases, the proportional relationship between the test time and the amount of helium gas sucked is maintained. Thereby, even if sliding heat_generation | fever arises with a shaft rotation, it turns out that a gas seal performance can be tested (evaluated), without receiving the influence of the expansion of gas accompanying a temperature rise.

As described above, according to the present embodiment, the gas seal performance is tested and evaluated without being affected by temperature change or pressure change by measuring the amount of gas movement from the gas composition. It becomes possible.

  In this embodiment, the shaft 12 is provided to be rotatable with respect to the housing 11, but the housing side may be provided to be rotatable with respect to the shaft member. In this case, the portion connected to the gas supply unit 20 and the gas chromatograph unit 30 may be provided on the shaft member side. Thereby, the gas seal performance can be tested (evaluated) with higher accuracy according to the specifications of the seal member.

  In the present embodiment, the housing 11 and the shaft 12 are rotatably provided, but the housing 11 and the shaft 12 may reciprocate. In this case, a gas seal performance test of a reciprocating seal member can be performed.

(Embodiment 2)
The gas seal performance test apparatus 1 described with reference to FIG. 1 in Embodiment 1 includes the gas chromatograph unit 30, and the gas chromatograph unit 30 and the apparatus main body 10 are connected by the communication path 36. The gas seal performance test apparatus according to the second embodiment of the present invention does not include the gas chromatograph unit 30 as in the first embodiment.

  That is, in the gas seal performance test apparatus according to the present embodiment, by collecting (taking out) the gas in the A chamber after the shaft 12 rotates for a predetermined time with respect to the housing 111 and the gas in the B chamber, The collected gas is analyzed by a gas chromatograph provided separately from the gas seal performance test apparatus.

  FIG. 2 is a schematic diagram showing the test apparatus head unit 110 of the gas seal performance test apparatus according to the present embodiment. The gas seal performance test apparatus according to the present embodiment is the same as the gas seal performance test apparatus 1 described in the first embodiment except that the gas chromatograph unit 30 and the communication path 36 are removed. The apparatus head unit 15 is different, and other basic configurations are the same as those of the first embodiment. The same configurations as those of the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  Also in the present embodiment, as in the first embodiment, the seal member S1 is a seal member to be evaluated, and the seal members S1 and S2 are attached so that the B chamber side is the sealing side, It is possible to enclose a fluid R such as oil or water.

  In the present embodiment, the housing 111 is provided with the same gas introduction portions (11c, 11d, 11e) as those in the first embodiment, and further, gases for collecting the gases in the A chamber and the B chamber, respectively. Sampling ports (gas outflow portions) 112 and 113 are provided.

  In the gas seal performance test, the motor 13 is operated to rotate the shaft 12 with respect to the housing 111 for a predetermined time, and then gas is sampled from the gas sampling ports 112 and 113 by a gas sampling member such as a syringe. With this configuration, the collected gas can be analyzed by gas chromatography.

  Here, in the housing 111, gas sampling bags 114 and 115 are provided so as to be connectable.

The gas sampling back is a bag-like member that is flexible and has low gas permeability, and is provided with a port that can be connected to a port (communication hole) provided in the housing 111. When the gas moves in the A chamber or the B chamber, the pressure changes unless the volume of the container changes. Therefore, the volume can be changed by providing a sampling back.

  By providing the gas sampling bags 114 and 115 in this way, it is possible to reduce the gas pressure change in the A chamber and the B chamber.

  FIG. 3 is a view for explaining another form of the test apparatus head section.

  The test apparatus head section 210 shown in FIG. 3 does not have the shaft holes 11a and 111a like the housing shown in FIGS. 1 and 2, but is provided with one end of the housing opened.

  In this opening, a magnetic fluid seal S3, which is a seal member using magnetic fluid, is provided in an annular gap between the shaft 12 and the housing 211 (corresponding to the position where the seal member S2 is provided in FIGS. 1 and 2). ing.

  In such a case, the sealing member S1 may be attached with the A chamber as the sealing side. It is possible to enclose a fluid R such as oil or water in the A chamber.

  Further, in such a case, the A chamber is replaced with a gas to be sealed (test gas), and the B chamber is replaced with a reference gas. That is, the test gas is introduced into the A chamber and the reference gas is introduced into the B chamber through the communication passages 23a and 23b and the gas introduction portions 11c and 11d from the gas cylinder 21 in which the reference gas and the test gas are respectively enclosed. So that

  During the gas seal performance test, the motor 13 is operated, the shaft 12 is rotated with respect to the housing 211 for a predetermined time, and then the gas is collected from the gas sampling ports 212 and 213 with a syringe, whereby gas chromatography is performed. It becomes possible to analyze by graphy.

  As described above, also in the present embodiment, it is possible to obtain the same effect as that described in the first embodiment. Further, the use of the magnetic fluid seal S3 can further improve the sealing performance for sealing the inside of the housing. That is, it is possible to more reliably block the gas in the room B from the atmosphere (the gas in the room B can be further prevented from leaking to the atmosphere side, and the atmosphere can be prevented from flowing into the room B. Can be suppressed more).

FIG. 1 is a schematic diagram showing a gas seal performance test apparatus according to Embodiment 1 of the present invention. FIG. 2 is a schematic cross-sectional view showing a test apparatus head portion of a gas seal performance test apparatus according to Embodiment 2 of the present invention. FIG. 3 is a schematic cross-sectional view showing another form of the test apparatus head portion in the second embodiment of the present invention. FIG. 4 is a diagram showing measurement results of a gas seal performance test performed using the gas seal performance test apparatus shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Gas seal performance test apparatus 10 Apparatus main body 11, 111, 211 Housing 11a, 111a Shaft hole 11b Bottom part 11c, 11d, 11e Gas introduction part 11f, 11g Gas outflow part 12 Shaft 13 Motor 14 Bearing 15, 110, 210 Test apparatus head Section 20 Gas supply section 21 Gas cylinder 22 Gas flow rate control section 23a, 23b, 23c Communication path 24, 25 Valve 30 Gas chromatograph section 31 Gas chromatograph 32 Gas sampler 33 Carrier gas section 34 Detector 35 Exhaust port 36 Communication path 37, 39 Valve 38 Needle valve 112,113 Gas sampling port 114,115 Gas sampling back

Claims (7)

Two members that are coaxially mounted relative to each other, and
By providing a test seal member in the annular gap between the two members, a first chamber and a second chamber separated by the test seal member;
Gas supply means for supplying different gases to the first chamber and the second chamber,
Driving means for relatively moving the two members;
In a state where a test seal member is provided in the annular gap and gas is supplied to the first chamber and the second chamber by the gas supply means, relative movement between the two members is performed by the drive means for a predetermined time. A gas outflow portion for allowing the gas enclosed in the first chamber and the second chamber to flow out of the first chamber and the second chamber, respectively, in order to analyze the gas sealed in the first chamber and the second chamber by gas chromatography. When,
A gas seal performance testing apparatus comprising: The two members are composed of a housing having an opening on one end side in the axial direction and a bottom end on the other end side in the axial direction, and a shaft member inserted through the opening,
By providing the opening side seal member in the annular gap on the opening side than the position where the test seal member is provided,
A space that is separated from the test seal member provided in the annular gap and is formed on the bottom side of the housing from the test seal member is defined as the first chamber,
The gas seal performance test apparatus according to claim 1, wherein a space formed by the test seal member and the opening side seal member provided in the annular gap is the second chamber. A space formed by the opening side seal member provided in the annular gap and formed on the opening side from the opening side seal member is defined as a third chamber,
In the housing, provided in each of the parts constituting the first chamber, the second chamber, and the third chamber, and provided with a gas introduction part for introducing the gas supplied by the gas supply means,
3. The gas seal performance test apparatus according to claim 2, wherein the gas outflow portion is provided in a portion of the housing that constitutes the first chamber and the second chamber. 4.   A gas to be evaluated is sealed in the second chamber, and a gas different from the gas to be evaluated is sealed in the first chamber, and the two members are relatively moved by the driving means for analysis by gas chromatography. 4. The gas seal performance test apparatus according to claim 3, wherein the gas to be evaluated is supplied to the third chamber by the gas supply means.   5. The gas seal performance test apparatus according to claim 2, wherein the two members are provided so as to be relatively rotatable, and the opening side seal member is configured by a magnetic fluid seal. A gas chromatograph for analyzing the gas sealed in the first chamber and the second chamber;
A communication passage that communicates the gas chromatograph with the gas outflow portions of the first chamber and the second chamber;
The gas seal performance test apparatus according to claim 1, comprising: By providing a seal member in an annular gap between two members that are coaxially and relatively assembled together, two chambers separated by the seal member are formed,
Gas sealing of the sealing member is performed by sealing the different gases in the two chambers and then relatively moving the two members for a predetermined time and then analyzing the gases sealed in the two chambers by gas chromatography. A gas seal performance evaluation method characterized by evaluating performance.

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