JP2005113983A - Mechanical seal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mechanical seal device to be manufactured at low cost and capable of sealing combustible gas and volatile gas by supplying lubricating liquid to the only seal surface, and capable of preventing contamination of a sealed fluid with the lubricating oil. <P>SOLUTION: In the mechanical seal device, pressure of the lubricating liquid T of a lubrication chamber 31 is set at the nearly atmospheric pressure condition, and a lubrication lead-in groove 3 for leading the lubricating oil T of the lubrication chamber 31 into a clearance between a lubrication chamber 31 side seal surface 2A and an opposite seal surface 10A is provided in one of the seal surface 2A and the opposite seal surface 10A. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a mechanical seal device. More specifically, the present invention relates to a mechanical seal device that seals combustion gas such as H2 gas and LNG, volatile gas, harmful gas, and the like.

Technical background

  Conventionally, a sealing device has not been a problem as a fire or pollution even if a small amount of air, water or oil to be leaked leaks to the outside. However, in recent years, it has become necessary to seal fluids such as special gases such as H 2 gas, LNG, toxic gas, and volatile gas. In this sealing device, two mechanical seals are arranged in parallel in the axial direction, and a high-pressure buffer fluid such as an inert gas is supplied between the two mechanical seals to thereby seal the two mechanical seals and the buffer fluid. There is a tandem type or double type mechanical seal that seals the fluid to be sealed by the sealing pressure (see, for example, Patent Document 1 and Patent Document 2). In this mechanical seal, a dynamic pressure generating groove is provided on a sliding sealing surface so that the sealing surface is in a non-contact state during sliding to prevent frictional heat and wear on the sealing surface. However, the non-contact type mechanical seal has a problem that a sealed fluid leaks because a gap is generated between the sealing surfaces. Also, the leaked harmful sealed fluid must be collected and disposed of. Furthermore, there are a problem that the apparatus is expensive due to a plurality of mechanical seals, and a problem that the installation place of the apparatus is enlarged. Furthermore, a sealing ring having a sealing surface provided with a dynamic pressure generating groove has a problem that it is expensive because it requires processing accuracy and quality.

  Furthermore, there exists the mechanical seal 100 shown in FIG. 7 as a 1st related technique similar to this invention (refer patent document 3). The mechanical seal 100 is completely different from the present invention in the use for sealing a sealed fluid. However, since there are similarities in shape, the technical differences will be described. This mechanical seal 100 is provided in a rotary joint. A casing 101 of the rotary joint includes a cylindrical frame 110 and a head portion 111 attached to the cylindrical frame 110. The casing 101 is provided with an annular frame 107 via bolts 112. A seal hole 113 is provided inside the casing 101. The seal hole 113 communicates with a flow path 114 that can communicate with an external flow path. Furthermore, one end of a main spindle 119 of the machine tool is housed in the seal hole 113 from the frame 107 side.

  A rotary joint is provided in order to allow the fluid M to pass through the flow path of the rotating main shaft 119 of the machine tool thus configured and the flow path 114 of the fixed casing 101. In the rotary joint, the floating sheet 102 in which the shaft portion 115 is movably attached to the seal hole 113 of the casing 101 and the rotary tube shaft 104 screwed into the flow path of the main shaft 119 are arranged in an opposed state. The flow path 118 of the floating sheet 102 and the flow path 120 of the rotary tube shaft 104 are communicated so that the sealed fluid M flows even in a rotating state.

  A fixing seal ring 121 is provided at the end of the floating sheet 102. On the sealing surface of the fixing seal ring 121, semicircular lubricating grooves 121C and 121D as viewed from above are provided radially at two equal intervals along the circumference on the inner circumference and the outer circumference. A rotating seal ring 122 is also provided on the end surface of the rotary tube shaft 104. The sealing surface of the rotating seal ring 122 is in a flat state. The flange portion 116 of the floating sheet 102 is elastically pressed by the spring 106 so that the sealing surface of the fixing sealing ring 121 and the sealing surface of the rotation sealing ring 122 are in close contact with each other. Further, a stop pin 105 is engaged with the notch 117 of the flange portion 116 so that the floating sheet 102 does not rotate. The lubrication groove 121C on the seal surface allows the sealed fluid that passes through the flow holes 121A of both the sealing rings 121 and 122 to flow into the lubrication groove 121C, and is pumped from the lubrication groove 121C to the seal surface by the pressure of the sealed fluid and lubricated. Is configured to do.

  The thus configured rotary joint introduces the sealed fluid from the lubricating groove 121C to the sealing surface using the pressure of the sealed fluid. In order to introduce the sealed fluid from the lubricating groove 121C to the sealing surface by the pressure of the sealed fluid, the sealed fluid requires pressure. Furthermore, the sealed fluid must be liquid. Therefore, when the gas to be burned is sealed as in the present invention, the mechanical seal having such a configuration cannot lubricate the seal surface, which causes seizure and wear on the seal surface. For this reason, in the case where the sealed fluid is a combusting gas, the sealed fluid also leads to combustion due to heat generated when the seal surface slides. Further, when the lubricating liquid is forcibly supplied from the outer peripheral surface side to the lubricating groove 121D on the outer peripheral surface, the lubricating grooves 121D and 121C provided on the inner and outer peripheral sides are connected to flow into the inner peripheral side, and the flow hole 121A There is a problem of being mixed into the sealed fluid flowing through. In addition, since a device for supplying the lubricating liquid is required, there is a problem of increasing the equipment cost. On the other hand, there is a problem that the gas sealed fluid flowing through the flow hole 121A is sent from the inner circumferential lubricating groove 121C to the outer circumferential lubricating groove 121D by centrifugal force and flows out to the outer circumferential side of the sealing surface. For this reason, the mechanical seal shown in FIG. 7 can be applied only to a rotary joint through which a liquid that can be lubricated flows.

  Further, as a second related technique of the present invention, there is a sealing ring 200 shown in FIG. 8 (see Patent Document 4). The sealing ring 200 is provided with a number of spiral grooves 215 on the sealing surface 210. This sealing surface 210 is arranged opposite to the sealing surface of the rotation sealing ring 122 in the same manner as the fixing sealing ring 121 of FIG. Then, a high-pressure fluid on one circumferential side is entrained and interposed between both seal surfaces. At the same time, a dynamic pressure is generated between the seal surfaces by the spiral groove 215 so that the seal surfaces are not in contact with each other. In this way, in a seal in which both seal rings are in a non-contact state, wear of the seal surface can be prevented, but since the fluid to be sealed leaks from between the two seal surfaces when the seal surface transitions to a non-contact state. It becomes a problem. For this reason, in the case of a special sealed fluid that does not allow leakage as in the present invention, or when lubricating oil cannot be mixed into the sealed fluid, there is a problem in using such a sealing ring 200 for a mechanical seal. Exist.

Japanese Patent No. 2728283 (FIG. 1) US Pat. No. 4,290,611 (FIG. 1) Japanese Unexamined Patent Publication No. 2000-130665 (FIG. 1) JP-A-53-126462 (FIG. 5)

The present invention has been made in view of the above problems.
Therefore, the problem to be solved by the present invention is to prevent frictional heat during sliding of the sealing surface of the sealing ring and to prevent wear due to sliding. Another object is to prevent lubricating oil from entering the sealed fluid. Furthermore, even if the fluid to be sealed is at a high pressure, the fluid to be sealed is prevented from leaking from the sealing surface. And it is in reducing the manufacturing cost of a mechanical seal apparatus.

The present invention has been made to solve the technical problems as described above. The technical solution for solving the problem is configured as follows.
The mechanical seal device of the present invention according to claim 1 is a mechanical seal device for sealing volatile fluid, low boiling point fluid, combustible fluid and the like. And a first sealing ring having a sealing surface, a second sealing ring having an opposing sealing surface in close contact with the sealing surface of the first sealing ring, and a cover provided on one circumferential surface side of the first sealing ring and the second sealing ring. A passage for sealing fluid, and a lubricating chamber for lubricating liquid on the other peripheral surface side of the first sealing ring and the second sealing ring, and the pressure of the lubricating liquid in the lubricating chamber is lower than the pressure of the sealed fluid In addition, a lubricating introduction groove is provided on one sealing surface of the lubricating chamber side sealing surface and the opposing sealing surface to guide the lubricating liquid in the lubricating chamber into between the sealing surface and the opposing sealing surface.

  In the mechanical seal device of the present invention according to claim 2, the lubrication chamber is provided on the inner peripheral surface side of the first seal ring and the second seal ring.

  According to a third aspect of the present invention, there is provided a mechanical seal device according to a third aspect of the present invention, wherein the lubrication introducing groove formed on the seal surface of the first seal ring is formed in an arc shape from the inner peripheral surface along the seal surface, The lubrication introduction groove is formed on the seal surface of half or less of the above.

  In the mechanical seal device according to the fourth aspect of the present invention, the lubricating liquid sealed in the lubricating chamber is lubricating oil, and the pressure of the lubricating liquid is substantially equal to the pressure of the lubricating oil from the supply source.

  In the mechanical seal device of the present invention according to claim 5, the second sealing ring is made of carbon material and has an opposing seal surface on the protruding end surface, and the radial width of the opposing seal surface is larger than the radial width of the seal surface. It is formed in small dimensions.

  In the mechanical seal device according to the first aspect of the present invention, since the lubricating introduction groove for allowing the lubricating liquid lower than the pressure of the sealed fluid to enter is formed between the sealing surface and the opposing sealing surface, Even when a special volatile sealed fluid is present on the side, the lubricating action of the sealing surface is exerted by the lubricating liquid. For this reason, heat generation between the seal surfaces is prevented, and wear of the seal surfaces is prevented. For example, even if the sealed fluid is a gas that burns, ignition of the combustion gas due to friction is prevented. In addition, since the lubricating action is exerted by the lubricating liquid in a contact state between both the sealing surfaces, the sealing ability is exhibited over a long period of time. Further, since the lubricating liquid in the lubricating chamber is lower than the pressure of the sealed fluid, the lubricating liquid can be prevented from entering the sealed fluid side. Also, the pressure of the lubricating liquid supplied to the lubricating chamber need only be sealed in the tank. For this reason, equipment such as a pump for supplying the lubricating liquid is not required, and the manufacturing cost of the mechanical seal device can be reduced.

  In the mechanical seal device according to the second aspect of the present invention, since the lubrication chamber is provided on the inner peripheral side of the both sealing rings, the lubricating liquid that has flowed into the lubrication introduction groove when the two sealing rings rotate relative to each other on the sealing surface. It becomes possible to intervene sufficiently between the sealing surfaces by the centrifugal force in between. For this reason, there is an effect that the lubricating liquid can be supplied between the seal surfaces even in a state where the lubrication introduction groove is minutely inserted between the seal surfaces. Also, heat generation between the seal surfaces is prevented to prevent the sealed fluid from igniting due to frictional heat, and the sealed fluid is prevented from leaking to the lubrication chamber through the lubricating liquid between the seal surfaces. To do. And the sealing effect between sealing surfaces is exhibited.

  In the mechanical seal device according to the third aspect of the present invention, the lubrication introduction groove is formed in an arc shape, and the lubrication introduction groove is formed in half or less of the width of the seal surface. It is possible to increase the contact surface with no lubrication introduction groove with the surface and to exert a sealing ability to seal the lubricating liquid together with the sealed fluid. Further, the lubrication introduction groove makes it easier for the lubricating liquid to enter between the seal surfaces to exert a lubricating action. Further, the arc-shaped lubrication introduction groove can introduce the lubricating liquid between the seal surfaces regardless of whether the rotation sealing ring rotates in the forward or reverse direction.

  In the mechanical seal device according to the fourth aspect of the present invention, the pressure of the lubricating liquid is substantially equal to the self-weight pressure of the lubricating oil, and the lubricating liquid is constituted by the lubricating oil. The lubricating oil can be infiltrated between the seal surfaces by the lubrication introduction groove. For this reason, the lubricating action between the seal surfaces is optimally exhibited. At the same time, even a combustible gas can be reliably sealed without any problem, and the lubricating liquid can be prevented from being mixed into the sealed fluid side. Furthermore, heat generation due to sliding of the seal surface is prevented, and heat generation of the sealed fluid that is combustion gas is prevented.

  In the mechanical seal device of the present invention according to claim 5, the second sealing ring is a carbon material, and the radial width of the opposing seal surface is smaller than the width of the seal surface. Lubricating liquid can be easily interposed on the sealing surface. For this reason, it is possible to prevent heat generation between the sealing surfaces and increase the surface pressure by the small width of the opposing sealing surface to exert a sealing effect.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a mechanical seal device according to an embodiment of the present invention will be described in detail with reference to the drawings. Each drawing described below is based on a design drawing.

  FIG. 1 is a mechanical seal device 1 showing a first preferred embodiment according to the present invention. The mechanical seal device 1 is attached to seal the sealed fluid L flowing in the passage 30 between the rotary shaft 50 and the housing 60. A hole is provided in the housing 60, and the rotary shaft 50 for power passes through the hole. A seal housing 61 is attached to the end surface of the housing 60 via an O-ring so as to close the hole. A stepped space is provided on the inner surface of the seal housing 61. A stainless steel case 61 </ b> A that holds the fixing seal ring 10 is fitted in this space via an O-ring. The case 61 </ b> A is held by a pin 61 </ b> C fixed to the seal housing 61 so as not to rotate. The seal housing 61 is provided with a supply passage 62 for supplying the lubricating liquid T in the tank (not shown). This tank is provided at a position higher than the mechanical seal device 1. Further, the seal housing 61 is provided with a fluid passage 63 for quenching or flushing the mechanical seal device 1 as necessary.

  A sleeve 51 is fitted on the rotary shaft 50. An oil seal 25 is provided at the atmosphere side end between the sleeve 51 and the seal housing 61. The oil seal 25 seals the lubricating liquid T supplied from the supply passage 62 from leaking to the atmosphere side. A stainless steel collar 51 </ b> A is fitted to the step portion of the sleeve 51. The collar 51 </ b> A has an O-ring disposed between the collar 51 </ b> A and the sleeve 51, and is fixed by a set screw 52. The inner peripheral step 2D of the rotation sealing ring 2 is fitted to the outer peripheral step of the collar 51A. A drive pin 51B is provided on the end surface of the outer peripheral step of the collar 51A. The drive pin 51B is engaged with a notch 2F (see FIG. 2) provided on the outer peripheral surface 2C side of the back surface of the rotary seal ring 2 so that the rotary seal ring 2 rotates together with the rotary shaft 50. Further, an O-ring 20A is disposed between the inner peripheral step 2D of the rotation sealing ring 2 made of carbonized carbonized material and the outer peripheral step of the collar 51A. The pressure of the sealed fluid L acts on the back surface of the rotation seal ring 2 to press the seal surface 2A. The pressure acting on the back surface of the rotation seal ring 2 is sealed by the O-ring 20A.

  As shown in FIGS. 2 and 3, the rotation sealing ring 2 is provided with a sealing surface 2A on one end surface. The sealing surface 2A is provided with a lubrication introduction groove 3 (3A) on the inner peripheral side. The lubrication introduction groove 3A is formed in an arc shape having a radius R along the seal surface 2A from the inner peripheral surface 2B side on the seal surface 2A. Further, the depth h in the radial direction from the inner circumferential surface 2B of the lubrication introducing groove 3 is formed to be equal to or less than h = H / 2 with respect to the radial width H of the seal surface 2A. The depth h in the radial direction of the lubrication introduction groove 3 is formed at H / 3 in FIG. Further, the axial width W of the lubrication introducing groove 3 is preferably 0.05 mm to 1.5 mm in FIG. The arcuate lubrication introduction groove 3 is formed so that the lubricating liquid can be supplied between the seal surfaces 2A and 10A even if the rotation sealing ring 2 rotates forward and backward. The shape of the lubrication introduction groove 3 is not necessarily an arc shape. For example, the semi-elliptical groove or the semi-elliptical groove can be inclined in the rotational direction with respect to the radial direction. However, the length of the semi-elliptical groove is not more than half of the radial width of the seal surface 2A, and the depth h of the lubrication introduction groove is very short with respect to the seal surface 2A. Further, the shape of the lubrication introduction groove 3 can be formed for forward rotation or reverse rotation.

  The fixing seal ring 10 disposed opposite to the rotation seal ring 2 is movably fitted to the two steps of the case 61A. As shown in FIG. 4, the fixing seal ring 10 has a notch groove 10 </ b> F formed on the back outer peripheral surface 10 </ b> C side. The cutout groove 10F is held by a locking pin 61B provided in the case 61A so that the fixing sealing ring 10 does not rotate. Further, an O-ring 20B is disposed between the first step surface 10D of the fixing seal ring 10 and the case 61A. Then, when the pressure of the sealed fluid L acts on the back surface of the fixing seal ring 10, the sealed fluid L is applied so that the fixing seal ring 10 can be pressed in the direction of the opposing seal surface 10A by the pressure of the sealed fluid L. Seal. Further, the fixing sealing ring 10 is always pressed elastically by the coil spring 21. A plurality of the coil springs 21 are arranged at equal intervals along the circumferential direction between the case 61 </ b> A and the fixing sealing ring 10.

  As shown in FIG. 4, an opposing seal surface 10 </ b> A that is in close contact with the seal surface 2 </ b> A is provided on the end surface of the fixing seal ring 10. The fixing seal ring 10 has an inner peripheral surface 10B and an outer peripheral surface 10C, and a first step surface 10D and a second step surface 10E on the inner peripheral surface 10B side. The fixing sealing ring 10 is made of a carbon material. Moreover, it can also be made from a carbonized carbon material if necessary. The radial width of the opposed seal surface 10A may be formed to be smaller than the radial width of the seal surface 2A.

The lubricating liquid T supplied from the supply passage 62 is supplied to the lubricating chamber 31. The lubrication chamber 31 is formed on the inner peripheral surface 2B of the rotation sealing ring 2 and the inner peripheral surface 10B side of the fixing sealing ring 10. The lubricating liquid T supplied to the lubricating chamber 31 is preferably a lubricating oil. The lubricating oil is the following oil. That is, engine oil, gear oil, brake oil, spindle oil, turbine oil, machine oil, flame retardant hydraulic oil, and the like. For example, for turbine oil, its viscosity may correspond to ISOVG 32 to 68. Also, other lubricating oils having a viscosity corresponding to ISOVG32 to 68 are preferred, but lubricating oils having a viscosity higher than this viscosity may be used. The lubricating liquid T is supplied between the seal surfaces 2A and 10A via the lubrication introduction groove 3. The lubricating liquid T supplied between the seal surfaces 2A and 10A seals the sealed fluid L between the seal surfaces 2A and 10A between the seal surfaces on the outer periphery of the region peripheral surface where the lubrication introduction groove 3 is provided. To do. For this purpose, the lubricity and viscosity of the lubricating liquid T are selected according to the properties of the sealed fluid L. In the first embodiment, the sealed fluid is H ₂ gas. LNG may be used as a sealed fluid. The sealed fluid L is a combustion gas, a volatile gas, a harmful gas, or the like. This mechanical seal device 1 exhibits a sealing effect even when the sealed fluid L is at a high pressure. For example, in the case of H ₂ gas, the gas pressure is 10 kg / cm ² G or more. Since this H ₂ gas is used for a reciprocating compressor of an automobile, it is necessary to prevent the lubricating liquid T from flowing into the combustion chamber of the engine. However, the sealing method of the mechanical seal device 1 of the present invention is the lubricating liquid T Can be prevented from flowing into the combustion chamber.

  FIG. 5 shows the surface pressure D of the opposing seal surface 10A of the sealing ring 10 for fixation. When the lubricant T is supplied from the lubrication introduction groove 3 between the seal surface 2A and the opposing seal surface 10A and the lubricant T is interposed between the seal surface 2A and the opposing seal surface 10A, the distribution of the surface pressure D shown in FIG. It becomes a state. For this reason, the sealed fluid L is sealed by a high surface pressure on the sealed fluid L side out of the surface pressure D distributed between the seal surface 2A and the opposed seal surface 10A. For this reason, the lubricating liquid T is prevented from flowing into the sealed fluid L side. At the same time, the lubricating liquid T interposed between the sliding surfaces of the seal surface 2A and the opposed seal surface 10A lubricates the seal surface 2A and the opposed seal surface 10A to prevent heat generation during sliding. Further, since the inner peripheral surface 10B side of the opposed seal surface 10A slides with the seal surface 2A provided with the lubrication introduction groove 3, the surface pressure D approaches zero. For this reason, the lubricating liquid T can easily enter from the lubrication introduction groove 3 between the sliding surfaces of the seal surface 2A and the opposing seal surface 10A. The lubricating liquid T is atmospheric pressure or the pressure of the own weight of the lubricating liquid T in the tank. Furthermore, nitrogen gas can be injected into the tank to make the pressure of the lubricating oil T lower than the pressure of the sealed fluid L and higher than the atmospheric pressure. For this reason, the lubricating liquid T may be supplied from the tank to the lubrication chamber 31 without being pumped by a pump, so that the cost of equipment can be reduced without using supply equipment. In addition, since only one mechanical seal is required to be configured from the rotation sealing ring 2 and the fixing sealing ring 10, the manufacturing cost of the mechanical seal device 1 can be reduced.

  FIG. 6 is a plan view of the rotary seal ring 2 of the mechanical seal device 1 showing the second embodiment. The rotary seal ring 2 is provided with eight trapezoidal lubricant introduction grooves 3 (3B...) Equally spaced along the circumference of the seal surface 2A as viewed from above. The depth in the radial direction from the inner peripheral surface 2B of each lubrication introduction groove 3B is formed to have a dimension of ½ or less of the width in the radial direction of the seal surface 2A. Further, good results were obtained when the axial width of the lubrication introducing groove 3B was 0.8 mm. The axial width of the lubrication introduction groove 3B was set in the range of 0.2 mm to 1.5 mm, but good results were obtained in all cases. Since the axial width of the lubrication introduction groove 3B is related to the viscosity of the lubricating liquid T, the width dimension is determined according to the viscosity.

  In the above embodiment, the configuration in which the lubrication chamber 31 is provided on the inner peripheral side of the rotation sealing ring 2 and the fixing sealing ring 10 has been described. However, depending on the conditions and pressure of the sealed fluid, the rotation sealing ring 2 is fixed. The lubrication chamber 31 can be provided on the outer peripheral side of the sealing ring 10 for use. Further, the passage 30 for the sealed fluid L can be provided on the inner peripheral surface side of the rotation sealing ring 2 and the fixing sealing ring 10.

  As described above, in the mechanical seal device 1 of the present invention, the lubricating liquid T supplied to the lubrication chamber 31 is at a pressure lower than the pressure of the sealed fluid L and is at atmospheric pressure or higher than atmospheric pressure. . For this reason, the lubricating liquid T need only be supplied and sealed in the lubricating chamber 31, so that it is not necessary to maintain the lubricating liquid T as a buffer fluid with a pump in a high pressure state as in the prior art. For this reason, since the supply equipment of the lubricating liquid T is unnecessary, the cost of the mechanical seal device 1 can be reduced. Further, since the lubricating liquid T is at a lower pressure than the sealed fluid L, it is supplied between the sealing surfaces 2A and 10A via the lubrication introducing groove 3. For this reason, the lubricating liquid T is held between the seal surfaces 2A and 10A to achieve a lubricating action, and frictional heat between the seal surfaces 2A and 10A during sliding can be prevented. Furthermore, the lubricating action and the sealing ability prevent the lubricating liquid T from flowing from the sealing surfaces 2A and 10A to the sealed fluid L side, so that the lubricating liquid T enters the sealed fluid and becomes a problem. Can be prevented. This problem is because, for example, when LNG is supplied to the internal combustion engine via the compressor, if the lubricating liquid is mixed into the combustion gas, the combustion is incomplete in the internal combustion engine.

  As described above, the mechanical seal device of the present invention seals volatile, flammable and harmful gases such as ammonia, LGN, ethylene, hydrocarbons, chlorinated water, gasoline, etc. and seals the lubricating liquid from the sealing surface. It is useful as a mechanical seal device that prevents the fluid from being mixed. In particular, the present invention is useful as a mechanical seal device that seals volatile gas and combustion gas such as a compressor and a cooler, and prevents the lubricating liquid from entering the sealed fluid from the sealing surface. Moreover, the manufacturing cost of the mechanical seal device is low, and the mechanical seal device can be used as a mechanical seal device with a simple structure.

It is sectional drawing of the mechanical seal apparatus concerning 1st Embodiment of this invention. FIG. 2 is a half cross-sectional view of a rotary seal ring in the mechanical seal device of FIG. 1. It is a front view of the sealing ring for rotation of FIG. FIG. 2 is a half cross-sectional view of a fixing seal ring in the mechanical seal device of FIG. 1. It is sectional drawing which shows the surface pressure state of the sealing surface in the sealing ring for fixation of FIG. It is a front view of the sealing ring for rotation in the mechanical seal apparatus concerning 2nd Embodiment of this invention. It is sectional drawing of the rotary joint shown as 1st related technology of this invention. It is a perspective view of a seal ring shown as the 2nd related art of the present invention.

Explanation of symbols

1 Mechanical seal device
2 Sealing ring for rotation
2A Seal surface
2B Inner surface
2C outer peripheral surface
2D inner peripheral step
2F Notch
3 Lubrication introduction groove
3A Lubrication introduction groove
10 Sealing ring for fixing
10A facing seal surface
10B Inner peripheral surface
10C outer peripheral surface
10D 1st step surface
10E Second step surface
10F Notch
25 Oil seal
30 passage
31 Lubrication chamber
50 axis of rotation
51 sleeve
51A color
51B drive pin
52 set screws
60 housing
61 Seal housing
61A case
61B Locking pin
61C pin
62 Supply passage
63 Fluid passage
D Surface pressure
H Width in radial direction
h Radial depth
L Sealed fluid
T Lubricant
W-axis width

Claims (5)

   A mechanical seal device for sealing a fluid such as a volatile fluid, a low boiling point fluid, a flammable fluid, etc., comprising: a first seal ring having a seal surface; and an opposing seal surface in close contact with the seal surface of the first seal ring A second sealing ring, a passage for sealed fluid on one circumferential surface side of the first sealing ring and the second sealing ring, and the other circumferential surface side of the first sealing ring and the second sealing ring. A lubricating chamber for the lubricating liquid, the pressure of the lubricating liquid in the lubricating chamber is lower than the pressure of the fluid to be sealed, and one of the sealing surface on the lubricating chamber side and the opposing sealing surface A mechanical seal device having a lubrication introduction groove for allowing the lubricating liquid in the lubrication chamber to enter between the seal surface and the opposed seal surface.   2. The mechanical seal device according to claim 1, wherein the lubrication chamber is provided on an inner peripheral surface side of the first seal ring and the second seal ring.   The lubrication introduction groove is formed in an arc shape from the inner peripheral surface along the seal surface, and the lubrication introduction groove is formed on a seal surface having a width dimension of 1/2 or less in the radial direction of the seal surface. The mechanical seal device according to claim 1 or 2, wherein the mechanical seal device is provided.   4. The lubricating liquid enclosed in the lubricating chamber is lubricating oil, and the pressure of the lubricating liquid is substantially the own weight of lubricating oil from a supply source. The mechanical seal device described in 1.   The second seal ring is made of carbon material and has the opposed seal surface on the protruding end surface, and the radial width of the opposed seal surface is formed to be smaller than the radial width of the seal surface. The mechanical seal device according to claim 1, claim 2, claim 3, or claim 4.

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