JP4172691B2 - Expanded graphite sealing material - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ring-shaped expanded graphite sealing material used for seals such as packings and gaskets. More specifically, the present invention is excellent in heat resistance, corrosion resistance and impact resistance, and the reinforcing member simply protrudes. The present invention relates to an expanded graphite sealing material that can be used as a packing, not a reinforcing material for prevention.
[0002]
[Prior art]
Expanded graphite materials have been widely used as sealing materials for packings, gaskets and the like since they have heat resistance, chemical resistance, flexibility, liquid impermeability, and the like. However, if such expanded graphite sealing material is used as it is, the sealing material will protrude into the gap between the equipment and the mounting part, resulting in a decrease in sealing performance and damage to the sealing material due to a decrease in the volume of the sealing material, resulting in a shortened service life. Has the disadvantage of causing
[0003]
Therefore, conventionally, as shown in a cross-sectional view in FIG. 6, an expanded graphite material 101 having a rectangular cross section is formed for the purpose of preventing the protrusion to the gap without impairing the properties of the expanded graphite material as described above. It is formed in a ring shape, and the corners of the four corners in the circumferential direction are covered and protected with reinforcing metal pieces 102a, 102b, 102c, 102d whose cross section is made of an ultra-thin steel plate made of stainless steel or the like. An expanded graphite sealing material 100 is known (see, for example, Patent Document 1).
[0004]
[Patent Document 1]
Japanese Utility Model Publication No. 2-4285 (Page 2, Fig. 1)
[0005]
However, in this expanded graphite sealing material 100, the L-shaped metal pieces 102a, 102b, 102c, and 102d for reinforcement correspond to the gaps between the contact-corresponding surfaces with the equipment, and prevent the protrusion to the gaps. However, since the surface of the L-shaped metal piece to be pressure-bonded to the expanded graphite material 101 is flat and narrow, there is a drawback in that the adhesion strength is low and it is easily peeled off by an external force. Further, in addition to such a weak impact resistance, the heat resistance and the corrosion resistance were not sufficient.
[0006]
Furthermore, the molding of the L-shaped metal piece is usually performed by drawing and requires a molding die for each size of the sealing material, resulting in a problem that the manufacturing cost increases.
[0007]
[Problems to be solved by the invention]
The present invention has been made under the circumstances described above, and its object is to remove the above-mentioned drawbacks of the conventional expanded graphite sealing material, and to have excellent heat resistance, corrosion resistance, and impact resistance. An object of the present invention is to provide an expanded graphite sealing material that can be manufactured at low cost, and that the reinforcing member is not merely a reinforcing material for preventing protrusion, but the member itself can be used as a packing.
[0008]
[Means for Solving the Problems]
The above object of the present invention is a sealing material formed by forming an expanded graphite material into a ring shape, and a protrusion preventing member having a rectangular cross section pressure bonded to a corner of the expanded graphite material is provided as an Inconel wire. A mesh twisted yarn is knitted into a square shape, and the surface of the cross section of the expanded graphite material that is press bonded to the corner is formed with mesh-like irregularities, and the protrusion member is press bonded to the expanded graphite material. This is achieved by providing an expanded graphite sealing material characterized by comprising:
[0012]
Hereinafter, the contents of the present invention will be described in detail based on examples.
[0013]
FIG. 1A is a plan view of an expanded graphite sealing material (hereinafter referred to as “the present sealing material”) according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA in FIG.
[0014]
The sealing material 1 is composed of a ring-shaped expanded graphite material 2 and protrusion preventing members 3 a, 3 b, 3 c provided at corners of the expanded graphite material 2. The protrusion preventing members 3a, 3b, 3c correspond to reinforcing members (L-shaped metal pieces) in the above-described conventional expanded graphite sealing material 100.
[0015]
The expanded graphite material 2 is formed in a ring shape by processing a known expanded graphite sheet having heat resistance, chemical resistance, flexibility, liquid impermeability, etc. into a tape shape and winding it around a mold having a predetermined shape. is there. As shown in FIG. 1 (B), the expanded graphite material 2 is formed in a trapezoidal shape having an inner diameter lower end 2u inclined, and the protrusion preventing members 3a, 3b, 3c are formed in the trapezoidal expansion. It is provided at three acute angle portions of the graphite material 2.
[0016]
The protrusion preventing members 3a, 3b, 3c are made of a material obtained by knitting a twisted yarn of Inconel (trade name of Metal Technology Inc.) wire mesh, which is generally known as an alloy containing Ni, Cr, Fe, C, etc., into a rectangular shape. ing. This material can withstand high-temperature and high-pressure conditions, has resistance to corrosion by various gases, acids, alkalis, etc., and has excellent absorbency against vibration and impact, so when applied to a sealing material, This is particularly preferable because it not only functions as a reinforcing member but also functions as a packing material.
[0017]
In addition, as the material of the protrusion preventing members 3a, 3b, 3c, it is also possible to use other materials such as knitted packing for high temperature and high pressure, a molded product of stainless mesh, stainless wire, stainless spring, stainless pipe and the like.
[0018]
In addition, it cannot be overemphasized that the shape of this sealing material 1, a magnitude | size, etc. can be changed into a various thing according to the use not only in this Embodiment.
[0019]
As shown in the cross-sectional views of FIGS. 2 (A) and 2 (B), the expanded sealing material 2 and the protrusion preventing members 3a, 3b, 3c are integrated from the state (A) to the state (B). Molded.
[0020]
3 (A), (B), (C), and (D) show the tools used when molding the sealing material 1 in the set order as indicated by dotted arrows, and (A) shows a rough die. 10, (B) is a finish punching die 20, (C) is a protrusion prevention die 30, and (D) is a stepping ring 40 in a sectional view.
[0021]
The rough casting mold 10, the finishing casting mold 20, and the protrusion preventing mold 30 are respectively from above, from the presser molds 11, 21, 31, inner diameter molds 12, 22, 32, and outer molds 13, 23, 33. Thus, the step ring 40 is prepared as an upper ring 41 and a lower ring 42 as one set. Using such a tool, the sealing material 1 is molded as follows.
[0022]
First, an expanded graphite sheet is processed into a tape shape and prepared to have a specified weight. Next, the tape-shaped expanded graphite sheet is wound around the inner diameter mold 12 of the rough casting mold 10 and set in the outer mold 13 together with the lower ring 42 of the step ring 40. Thereafter, the upper ring 41 is set, the presser mold 11 is inserted into the outer mold, and the expanded graphite material 2 is preformed into a ring shape by applying pressure from above.
[0023]
Next, the protrusion preventing members 3 a, 3 b, 3 c are prepared to a specified length and set in the inner diameter mold 32 of the protrusion preventing mold 30. This is set in the outer shape die 33, and the presser die 31 is inserted and pressurized from above, so that the protrusion preventing members 3a, 3b, 3c are preformed into a predetermined shape. At the time of this molding, the surfaces of the protrusion preventing members 3a, 3b, 3c that are pressure-bonded to the expanded graphite material 2 are finely meshed by embossing or the like. Thus, by providing a concavo-convex portion on the pressure bonding surface, the bonding area is increased, and when the expanded graphite material 2 enters the concavo-convex portion, the adhesion strength due to the pressure bonding between them is increased.
[0024]
After the preliminarily molded expanded graphite material 2 and the protrusion preventing members 3a, 3b, 3c are set on the inner diameter mold 22 and the outer shape mold 23 of the finishing die 20, the presser mold 21 is inserted from above, and the high pressure Compress and integrally mold. Thus, the seal material 1 is completed.
[0025]
Thus, in this sealing material 1, since the protrusion preventing members 3a, 3b, 3c are firmly pressure-bonded to the corners of the expanded graphite material 2, the conventional expansion can be achieved even when subjected to a considerably strong impact or vibration from the outside. It does not peel off like a graphite sealing material.
[0026]
Further, the molding method described above is the same as normal packing molding, and is not a drawing process like the conventional L-shaped reinforcing metal piece. On the other hand, it is only necessary to prepare the protrusion preventing mold 30 for each predetermined size, for example, every 50 mm, without requiring a molding mold, so that the manufacturing cost can be reduced.
[0027]
Next, the usage method of this sealing material 1 produced as mentioned above is demonstrated based on FIG.4 and FIG.5.
[0028]
FIG. 4 shows an example of use of the present sealing material 1. In order to prevent the fluid 50 from leaking through the gap between the main body 51 and the bonnet 52, the bonnet 52 is illustrated as illustrated in FIG. 4. This shows a case where the presser lid 60 is pressurized and sealed from the direction of the arrow Y2 after being mounted in the recess 53 provided above the direction from the direction of the arrow Y1.
[0029]
When the sealing material 1 is loaded into the recess 53, as shown in an enlarged view of the main part in FIG. 5A, the inner peripheral surface of the sealing material 1 is used to eliminate the interference between the components and facilitate assembly. A gap d is provided between 1 f and the side wall surface 52 f of the bonnet 52. In this state, when the sealing material 1 is pressed and tightened from above by the presser lid 60 in the direction of the arrow Y2, the sealing material 1 is deformed as shown in FIG. 5B, and the protrusion preventing member 3a and the expanded graphite material are used. 2 sticks to the side wall surface 52f and at the same time, the protrusion preventing member 3a protruding into the gap d rises upward to completely seal the gap d. At this time, the protrusion preventing members 3b and 3c and the expanded graphite material 2 act in the same manner on the outer peripheral surface side of the sealing material 1 and completely seal the gap with the main body 51. In this way, leakage of the fluid 50 is prevented.
[0030]
【The invention's effect】
As described in detail above, the expanded graphite sealing material according to the present invention is not only heat resistant and corrosion resistant, but also has an anti-extrusion member that is firmly pressure bonded to the expanded graphite material. Excellent earthquake resistance.
[0031]
Also, unlike drawing, etc., the molding method is the same as normal packing molding, and there is no need to prepare a protrusion prevention die for each size, which can reduce the manufacturing cost and make the product inexpensive. Can be mass-produced.
[0032]
In particular, if the protrusion prevention member is made of a material in which twisted yarns of Inconel wire mesh are knitted into a square shape, this protrusion prevention member is not only a reinforcing material for preventing protrusion, but the member itself can be used as a packing. A graphite sealing material can be provided.
[Brief description of the drawings]
1A is a plan view of an expanded graphite sealing material according to an embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA of FIG.
2A is a cross-sectional view showing a state before integral molding, and FIG. 2B is a cross-sectional view showing a state after integral molding.
FIG. 3 is an exploded view of a tool used when molding an expanded graphite sealing material according to the present invention, where (A) is a rough punching die, (B) is a finish punching die, and (C) is protruding. (D) is a cross-sectional view of a stepping ring.
FIG. 4 is a sectional view showing an example of use of an expanded graphite sealing material according to the present invention.
5 is an enlarged view of a main part of FIG. 4, in which (A) is a state before use, and (B) is a cross-sectional view showing a state after use.
FIG. 6 is a cross-sectional view of a conventional expanded graphite sealing material.
[Explanation of symbols]
1 (related to the present invention) expanded graphite sealing material 2 expanded graphite materials 3a, 3b, 3c protrusion preventing member 10 rough punching mold 20 finish punching mold 30 protrusion preventing mold 40 stepping ring 100 (conventional) Expanded graphite sealing material 101 expanded graphite material 102a, 102b, 102c, 102d reinforcing metal piece

Claims (1)

A sealing material formed by expanding expanded graphite material into a ring shape, a protrusion preventing member having a rectangular cross section that is pressure- bonded to a corner of the expanded graphite material, and a twisted yarn of Inconel wire mesh in a square shape with knit, and characterized in that by subjecting the mesh-like unevenness is formed on the surface to be engaged under pressure in the expanded graphite material corners of the cross section, comprising the anti-extrusion members to pressure bonded to the expanded graphite material Expanded graphite sealing material.

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