CN106415087A

CN106415087A - Seal structure for butterfly valve

Info

Publication number: CN106415087A
Application number: CN201580017251.3A
Authority: CN
Inventors: 邱明平
Original assignee: Kitz Corp
Current assignee: Kitz Corp
Priority date: 2014-03-28
Filing date: 2015-03-26
Publication date: 2017-02-15
Anticipated expiration: 2035-03-26
Also published as: JP6495243B2; WO2015147197A1; JPWO2015147197A1; CN106415087B

Abstract

Provided is a seal structure for a butterfly valve with which sealing characteristics near a valve vane are improved and an increase in operating torque is prevented by suppressing a force that deforms a resin lining layer during operation when the valve is closed, said butterfly valve being openable/closable while ensuring sealing characteristics and having a low operating torque even when the resin lining layer is thickened. A lining layer (10) comprising a resin material is provided on a disk (2) surface and on the inner peripheral surface of a body (3), and at least a valve vane portion (20) is sealed by press contact to an inner peripheral seal surface (21) of the body (3) when a stem (5) is rotated. The internal diameter of a sheet liner (11) is configured, when the valve is open, to be an internal diameter (Phid2) that is deformed by the elastic force of a backup rubber (4) so as to be smaller than the external diameter (PhiD1) of the disk (2), whereas said internal diameter of the sheet liner (11) is configured, when the valve is closed, to be an internal diameter (Phid1) prior to deformation by the elastic force of the backup rubber to a smaller diameter (4) due to a pressing force from the disk (2), said pre-deformation internal diameter (Phid1) being configured to be the same as the disk external diameter (PhiD1) or somewhat larger than the disk external diameter.

Description

The seal construction of butterfly valve

Technical field

The present invention relates to the seal construction of butterfly valve, resin-lined particularly to implementing to valve body and clack box inner peripheral surface Seal construction near the sealing of the valve wing of butterfly valve and clack box.

Background technology

Butterfly valve is to be guaranteed with the boss portion contact surface of seat ring by the boss portion of the root of the stem shaft being formed at valve body The valve wing contact surface of the sealing near stem shaft dress portion, the valve wing outer peripheral face by valve body and seat ring guarantees than stem shaft dress portion Seal construction by the side face sealing of valve flank.By such butterfly valve basic industry or semiconductor manufacturing factory Middle using and in the case of so that highly corrosive fluid is flow through or be used in the chemical fluid such as chlorine or hydrochloric acid, medicinal liquid, solvent, food In the case of in stream etc. of association, it is more that the valve body of convection cell contact and clack box inner peripheral surface implement resin-lined situation.Make For this resin-lined part, chemical resistance or thermostability good fluororesin are usually used, but because fluororesin lacks flexibility, so The side face sealing being possible to valve flank declines and seat leakage occurs.So, in order to improve the sealing of the valve flank of butterfly valve Property, generally propose by the circle of rubber system be disposed in resin-lined part rear side, using this rubber system circle elastic repulsive force more Mend the deficiency of the elastic force near the valve wing and improve the butterfly valve of sealing.

As this butterfly valve, for example, disclose the butterfly valve of patent documentation 1.In this butterfly valve, as clack box The resin-lined layer being made up of the seat ring of fluororesin is arranged on the inner surface of valve body, between this seat ring and valve body The bracing ring of rubber system inserted by folder, plays elastic force by this bracing ring in sealing and guarantees the sealing and valve body between.In setting In the case of the seal construction of such butterfly valve, attaching bracing ring in the groove on being formed at valve body, via this support Seat ring is installed on valve body circle, then, in attaching and installs valve body via valve rod on the valve body of this seat ring.

In this butterfly valve, if so that valve body is rotated by valve rod operation the valve flank of valve body is pushed to seat ring, Then this seat ring is while compressed to the outer direction together with bracing ring, and valve seal.

Same technology is also disclosed that in patent documentation 2.In this butterfly valve, describe the half of the outer peripheral edge making valve body Footpath is set to the radius phase with the inner peripheral surface of the valve seat diametrically being fastened by the elastomeric element that annular rubber etc. is constituted Deng or more slightly larger than the radius of the inner peripheral surface of valve seat.

Patent documentation 1：Japanese Unexamined Patent Publication 2003-166654 publication.

Patent documentation 2：Japanese Unexamined Patent Publication 2012-219819 publication.

But, in the butterfly valve of patent documentation 1, due to when valve closing seals except resist bracing ring elastic force power with Also need to the power of seat ring itself compression outward, so bringing the rising of operation torque.In the case, if suppression seat ring Compression, then can reduce while guaranteeing sealing operation torque, but not on the books and hint such for suppressing The shape of the compression of seat ring and construction.And then, it is used in valve closing so that the power that seat ring compresses is become with the thickness of seat ring Become much larger greatly, have the further up problem of operation torque.Therefore, it is also difficult to set seat ring in this butterfly valve Count thicker and so that chemical resistance and thermostability is improved.

On the other hand, in the butterfly valve of patent documentation 2, be equivalent to because the radius of the inner peripheral surface of valve seat represents that attaching The size of the state of the elastomeric element of bracing ring（Fig. 2 with reference to patent documentation 2）, so when valve closing seals, with patent documentation 1 Situation same, in addition it is also necessary to power by seat ring itself compression in addition to resisting the power of elastic force of bracing ring.

Additionally, patent documentation 1,2 is all because bracing ring is its thickness flat pattern less than width dimensions, thus with The opening and closing of valve and by bracing ring, swimmingly undergauge or expanding aspect need to improve.

Content of the invention

The present invention is to develop to solve the problems, such as conventional, its objective is to provide one kind especially improving near the valve wing Sealing while, when valve closing operates suppression the power of resin-lined layer compression prevented from operate the rising of torque, increasing Plus also can be while sealing is guaranteed while opening with certain relatively low operation torque in the case of the thickness of this resin-lined layer The seal construction of the butterfly valve of closed operation.

To achieve these goals, the invention about technical scheme 1 is a kind of seal construction of butterfly valve, on valve disc surface With via in supporting and being respectively provided with the inner peripheral surface of the rubber valve body that can rotate ground axle suspension valve disc and be made up of resin material Lining, and it is being located at the valve shaft hole axis dress valve at as the diametric(al) opposed locations of the valve seat bush of valve body sidelining layer Bar, when by this valve rod rotation process up to major general's valve disc valve alar part crimping be sealed on valve body inner peripheral surface；Valve seat bush interior Footpath sets as follows：In valve opening, the internal diameter of above-mentioned valve seat bush is deformed into the external diameter with valve disc under the elastic force effect supporting rubber It is in a ratio of the internal diameter of path, on the other hand, valve disc pushes in valve closing, become and become to path under the elastic force effect supporting rubber Internal diameter before shape, the internal diameter before this is deformed is set to comprise tolerance identical with valve disc external diameter or more slightly larger than valve disc external diameter.

Invention about technical scheme 2 is a kind of seal construction of butterfly valve, by by support rubber thickness be set to The width dimensions of this support rubber substantially with size or slightly longer than the width dimensions of this support rubber, in valve closing easily by valve seat The internal diameter of bushing is restored to the internal diameter before deforming.

Invention about technical scheme 3 is a kind of seal construction of butterfly valve, by the internal diameter of valve seat bush when in valve closing To the internal diameter before deformation restore when, rubber will be supported with expanding and protrusion that swell in the direction of the width is received into and is located at valve In clearance portion between body and valve seat bush.

Invention about technical scheme 4 is a kind of seal construction of butterfly valve, and the width supporting rubber is set to and valve disc The roughly the same size of valve wing difference.

Invention about technical scheme 5 is a kind of seal construction of butterfly valve, and inner liner is fluororesin.

Invention about technical scheme 6 is a kind of seal construction of butterfly valve, in the valve disc as valve disc sidelining layer Two surface sides of the valve flank end of lining arrange the conical surface of predetermined angular, formed and crimp sealing with valve seat bush between these conical surfaces Sealing, the width of this sealing is set to the size roughly the same with the width of the arbor end side of valve disc.

According to the invention about technical scheme 1, the internal diameter of valve seat bush restores under the elastic force supporting rubber in valve opening For being deformed into the internal diameter being in a ratio of path with the external diameter of valve disc, in valve closing for valve disc pushes under the elastic force supporting rubber to Internal diameter before path deformation, is set to identical with valve disc external diameter by the internal diameter before deforming this（Comprise tolerance）Or outside than valve disc Footpath is slightly larger, does not need the power of resin-lined layer compression when valve closing operates, is prevented from operating the rising of torque.And, It is also possible to not apply to operate the power of this liner layer compression for valve closing sealing in the case of increased the thickness of resin-lined layer State, it is possible to be easily opened and closed operation with certain relatively low operation torque.

According to the invention about technical scheme 2, by the thickness supporting rubber is set to the substantially same size with width dimensions Or slightly longer than the width dimensions of this support rubber, the deformation leeway of radial direction becomes big, due to by this bracing ring with the opening and closing of valve Swimmingly undergauge or expanding, the internal diameter of valve seat bush is easily restored to the internal diameter before deforming, it is possible to preventing from operating torque Rising.

According to the invention about technical scheme 3, by being received into the protrusion of expanding support rubber in clearance portion, send out Wave the pushing sealing force of equalization, be able to maintain that there is no excessive sealing state.

According to the invention about technical scheme 4, valve seat lining when can guarantee valve closing in being provided with the scope supporting rubber Cover the sealing with valve disc and be reliably prevented seat leakage, even valve disc is not fully rotated into the situation of closed state, Also this error is absorbed and play higher sealing.

According to the invention about technical scheme 5, by making inner liner be fluororesin, chemical resistance and heat-resisting can improved Operation torque when while property operating valve closing suppresses relatively low, and the sealing because of valve disc of this inner liner can be suppressed to bring Wear and tear and deteriorate and improve durability.

According to the invention about technical scheme 6, when valve closing seals from arbor to as with the sealing surface of valve seat bush Valve disc liner substantially uniformly transmits pushing force, while playing good torque by uniform face pressure sealing force, makes valve Alar part uprises and is reliably prevented seat leakage with the sealing of valve body inner peripheral surface.

Brief description

Fig. 1 is the axonometric chart of the Partial Resection of butterfly valve.

Fig. 2 is the central longitudinal section of the butterfly valve of Fig. 1.

Fig. 3 is the central horizontal magnification sectional view of the butterfly valve of Fig. 1.

Fig. 4 is the central longitudinal section of the butterfly valve of Fig. 2.

Fig. 5 is the main enlarged view of a portion of Fig. 4.

Fig. 6 is that the part of the attaching state of the valve seat bush in the central horizontal magnification sectional view represent Fig. 3 omits section view Figure.

Fig. 7 is the sectional view representing the state of valve disc rotation in Fig. 3.

Fig. 8 is the enlarged partial cross section representing near the valve alar part of valve disc.

Fig. 9 is the sectional view representing valve seat bush.

Figure 10 is the central transverse sectional view of the comparative example representing butterfly valve.

Figure 11（a）It is the axonometric chart representing valve seat bush.Figure 11（b）It is the longitudinal section of valve seat bush.

Figure 12（a）It is the axonometric chart representing valve disc.Figure 12（b）It is the longitudinal section of valve disc.

Figure 13 is the sectional view representing the state making valve seat bush deform.

Figure 14 is the A-A sectional view of Figure 13.

Figure 15（a）It is the axonometric chart of the valve seat bush that valve disc in attaching.Figure 15（b）It is the valve seat bush that valve disc in attaching Longitudinal section.

Figure 16（a）It is the axonometric chart of the valve seat bush that valve rod in attaching.Figure 16（b）It is the valve seat bush that valve rod in attaching Longitudinal section.

Figure 17 is to represent the side view supporting rubber.

Description of reference numerals

1 valve body

2 valve discs

3 valve bodies

4 support rubber

5 valve rods

10 inner liners

11 valve seat bush

12 valve disc liners

12a inclined plane

The 12b conical surface

12c sealing

13 valve shaft holes

20 valve alar parts

φ D1 valve disc external diameter

The internal diameter of valve seat bush during φ d2 valve opening

The internal diameter of valve seat bush during φ d1 valve closing

L supports the width of rubber

S valve wing difference

The width of Wa sealing

The width of the arbor end side of Wb valve disc.

Specific embodiment

Hereinafter, explained based on accompanying drawing the butterfly valve of the present invention seal construction preferred embodiment and its make With.In Fig. 1, Fig. 2, represent one of the butterfly valve of seal construction using the present invention, in figure 3, represent the butterfly valve of Fig. 1 Central horizontal magnification sectional view.Hereinafter, represent that the size example of the butterfly valve of nominal diameter 100A illustrates.

The butterfly valve of Fig. 1（Hereinafter referred to as valve body 1）For example it is used in semiconductor manufacturing factory or the pipe of food association In road etc..Valve body 1 has valve disc（ジスク）2nd, the valve body 3 of barrel shape, support rubber 4, by top valve rod 5a and lower valve The valve rod 5 that bar 5b is constituted, on the surface of valve disc 2 with via supporting rubber 4 can rotate the valve body 3 that ground axle suspension valve disc 2 Inner circumferential side, is provided with the inner liner 10 being made up of valve seat bush 11, valve disc liner 12.

As shown in figure 5, in valve body 1, being located at the valve shaft hole 13 at the diametric(al) opposed locations of valve seat bush 11 Axis fills valve rod 5, near this stem shaft dress portion 14, in the rotation process of valve rod 5 by boss portion 15 He being located at valve disc 2 side Be located at the boss portion sealing surface 16 of valve body 3 side by valve disc 2 up and down respectively sealing it is ensured that so-called upper-lower seal（Once close Envelope）Sealing.In the inner circumferential side of valve body 1, as shown in figure 3, by will be careful in the valve alar part 20 of valve disc 2 and valve body 3 Front cover 21 crimps sealing in a circumferential direction it is ensured that the side face sealing of this valve alar part 20 side, prevents seat leakage.

In Fig. 1～Fig. 5, the valve disc 2 of valve body 1 has arbor（Core gold）22, this arbor 22 is for example with stainless steel alloy Be formed as discoid for material.On arbor 22, such as with 3mm about thickness be covered with above-mentioned valve disc liner 12, this valve disc Liner 12 becomes the inner liner 10 that valve disc 2 surface connects liquid level side.Valve disc liner 12 is made up of resin material, in present embodiment In, by PFA（Tetrafluoroethene perfluorinated alkoxy vinyl ether copolymer）Deng fluororesin setting, can play higher corrosion-resistant Property and thermostability.Valve disc liner 12 integratedly covers in this arbor via the through hole 23 of the appropriate position being formed at arbor 22 On the outside of 22 positive and negative, prevent the disengaging from arbor 22.

As shown in Fig. 2, Fig. 4, Fig. 5, upper and lower in valve disc 2, then liner cylindrical portion 26 described later, as valve rod hole portion shape Become the polygon hole portion 24 having the hexagon shape for inserting top and the bottom valve rod 5a, 5b.In valve rod hole portion 24, insert embedding respectively Close the polygonal portion of the hexagon shape that each end side in top and the bottom valve rod 5a, 5b is formed, thus, valve disc as connecting portion 25 2 can be rotated the earth's axis via these top and the bottom valve rod 5a, 5b is contained in valve body 3.By such installation constitution, top and the bottom valve Bar 5a, 5b can be arranged with respect to the valve disc 2 being installed on valve body 3 with plugging off.The valve rod hole portion 24 of valve disc 2 side, top and the bottom valve As long as the connecting portion 25 of bar 5a, 5b side can mutually be fitted together to or hexagon shape beyond polygon-shaped, for example, it is possible to It is located in the various inserted structures that top and the bottom valve rod and valve disc can be decomposed by two sides opposite side or corner axle, spline connection etc..

In Fig. 4, Fig. 5, in the insertion side of upper and lower, valve disc liner 12 top and the bottom valve rod 5a, 5b as valve disc 2, with This valve disc liner 12 forms liner cylindrical portion 26.By this liner cylindrical portion 26 by the connecting side of top and the bottom valve rod 5a, 5b Cover in the axial direction.

As shown in the enlarged partial cross section of Fig. 8, in two surface sides of valve disc liner 12, from the center side of valve disc 2 to end Be provided with inclined plane 12a near side, then this inclined plane 12a and in valve alar part 20 side end, conical surface 12b is provided with predetermined angular.? Between the conical surface 12b of two surface sides, it is formed with sealing 12c in vertical direction in figure, this sealing 12c can in valve closing Crimping is sealed on valve seat bush 11.

In the present embodiment, conical surface 12b from inclined plane 12a being obliquely installed with tilt angle alpha, this tilt angle alpha quilt It is set to 20 °.In the case, it is set as 45 ° by the inclination angle beta from vertical surface side, the width Wa of sealing 12c and arbor The width Wb of 22 terminal part 22a is set as roughly the same width W.For example, the width Wb in the end side of arbor 22 is 3mm In the case of, the width Wa of sealing is set to 3mm, by the structure so making valve disc end side be width Wa=width Wb Make, power sealing 12c being subject to because of the pushing with valve seat bush 11 with the terminal part 22a of arbor 22 with sealing 12c identical width bears, and prevents the decline of the sealing face pressure at this position, is arranged on and has standby higher torque during valve closing concurrently Can be with the seal construction of sealing.Define the external diameter φ D1 of the valve disc 2 of above-mentioned valve disc liner 12（With reference to Fig. 3）In this embodiment party It is set as the external diameter of φ 100mm in formula.

As shown in Figure 1 and Figure 2, the valve body 3 of the above-mentioned valve disc of attaching 2 is made up of top valve body 3a, bottom valve body 3b, their examples As shaped by cast irons such as malleable cast iron, being bolted 27 can mutually removably fix.Valve rod 5 axle in top and the bottom valve body 3a, 3b Dress side is provided with axle dress hole 28,28, difference attaching top and the bottom valve rod 5a, 5b in these each axle dress holes 28.Then this axle dress hole 28, It is provided with the attaching recess 29,29 of expanding shape in the side that keeps of valve disc 2, interior as shaft sealing part 17 via this attaching recess 29 Dress seal sleeve 30, seal member 31, disc spring 32, plate member 33, also attaching bearing 34.

In the side face sealed sides of the valve alar part 20 of top and the bottom valve body 3a, 3b, with the width of 10mm, attaching slot 35 is formed as The depth more shallow than the thickness supporting rubber 4, removably attaching can support rubber 4 in this attaching slot 35.In top and the bottom valve body The both sides of 3a, 3b, being provided with can be by bolt 27 by the bolt hole being fixedly connected with each other 36.

Valve body 3 is for example covered and attaching with the wall thickness of 3mm by the valve seat bush 11 shown in Fig. 9 in the inner circumferential side of valve body 3, should Valve seat bush 11 becomes the inner liner 10 connecing liquid level side.Valve seat bush 11 is made up of resin material, in the present embodiment, with valve The situation of disk liner 12 is same, with the setting of the fluororesin such as PFA.Valve seat bush 11 has the annulus being installed in valve body inner circumferential side 40 and project flange part 41 on the two ends outer peripheral edge being formed at this annulus 40, the valve rod 5 in the top and the bottom of annulus 40 Be formed with axle charging tube part 42,42 at attachment positions, can be provided with inserting respectively in this axle charging tube part 42 top and the bottom valve rod 5a, 5b.

The axle dress side of top and the bottom valve rod 5a, 5b in the inner circumferential of annulus 40 and valve disc 2, fills direction in the axle of valve rod 5 On project and be formed with above-mentioned boss portion sealing surface 16, in a circumferential direction, across this boss portion sealing surface 16 in valve alar part 20 The side that sealing 12c abuts is formed with the above-mentioned inner circumferential sealing surface 21 of arc-shaped.

Inner circumferential sealing surface 21 is the plane parallel with stream shaft core direction, additionally, the sealing 12c of valve disc 2 is formed as making It is the R shape of the part with the sphere of wick-like with discoideus valve disc 2.It is made up of these inner circumferential sealing surfaces 21 and sealing 12c Valve base sealing be two positions contact area more carefully be wire so-called " linear sealing ", so frictional force is less, be conducive to by The rising of operation torque during valve closing suppresses relatively low.

The inner circumferential sealing surface 21 of present embodiment is set to, and makes the internal diameter φ d1 in Fig. 6 that this track formed be φ 100mm, the width L of inner circumferential sealing surface 21 is in Fig. 6（b）In be set to 10mm.In the rear side of inner circumferential sealing surface 21, with valve It is equipped with support rubber 4 between body 3, from this support rubber 4, the inner circumferential sealing surface 21 of valve seat bush 11 is pushed away to the direction of undergauge Pressure.

Left and right shown in Fig. 3 two supports rubber 4,4 for example to be formed as being attached in attaching slot 35 by fluorubber Width and length dimension, in fig. 2, are disposed in the left and right sides of valve body 3 in the way of clipping seal sleeve 30 respectively.In the figure 7, Support rubber 4 to be set to the width of the size roughly the same with valve wing difference S of valve disc 2, be set to valve wing sealed sides in The roughly the same length of the width L of all sealing surfaces 21.In Fig. 6（b）In, support the thickness T of rubber 4 to be set as identical with width L Size, the width L in present embodiment and thickness T is set as 10mm.Here, represent can be by valve disc 2 for valve wing difference S Carry out the ultimate value of the inclination of valve alar part 20 of valve closing sealing, according to valve alar part 20 end from the end face of valve body 3 to a side The difference of length S1 and length S2 of valve alar part 20 end from the end face of valve body 3 to another side obtain.

The thickness T supporting rubber 4 passes through to be set as and width L identical size as described above, crushes for certain Rate ensure that suitable broken surplus.If in the case that thickness T is relatively thin because of the deviation of size the amplitude of fluctuation of percentage of damage Become big, operation torque during valve closing steeply rise or close deterioration probability higher.

On the other hand, if thickness T is blocked up, in the maximum outside diameter of valve body 3 and minimum outer diameter by the size limitation of pipe arrangement Under conditions of attaching slot 35 must be set as deeper size it is possible to cannot ensure for meeting valve body compressive resistance Little wall thickness.If additionally, blocked up, the impact change being brought by thermal expansion is big, and operation torque during valve closing is possible to steeply rise.

Thus, support the thickness T of rubber can to set in the scope of 0.9L T 1.1L, be preferably set as T=L Or T 1.1L.

So, the thickness T supporting rubber 4 is set to and support rubber 4 width L size substantially with size or slightly Long, by using the support rubber 4 of narrower width compared with the support rubber 4 of flat pattern as prior art, expanding change Obtain easily, by easily the internal diameter of valve seat bush 11 being restored to the internal diameter before above-mentioned deformation in valve closing, be prevented from operating The rising of torque.

Inner circumferential size x of the support rubber 4 shown in Figure 17 is formed as and the central footpath being equivalent to the attaching slot 35 shown in Fig. 2 The substantially same size of arc length y.The end 4a supporting rubber 4 is cut so that its whole face can be closely contacted on seal sleeve by oblique On 30 outer peripheral face.By these structures, be attached to support rubber 4 in attaching slot 35 will not local relaxing, can be by valve The back side of the inner circumferential sealing surface 21 of seat pad set 11 equably pushes.

Here, in order to represent the feature of the seal construction of the present invention, it is divided into 3 states to illustrate.

As Fig. 6（a）Shown, if valve seat bush 11 is arranged in the state of not having attaching to support rubber 4, valve disc 2 In the case of on valve body 3, that is, under the formation state of valve seat bush 11, the internal diameter φ d1 of the inner circumferential sealing surface 21 of valve seat bush 11 It is set to and valve disc external diameter φ D1 identical φ 100mm.

Now, in the figure, from the bottom surface of attaching slot 35 to inner circumferential sealing surface 21 be about 11.7mm apart from HA, from dress The bottom surface of access slot 35 is about 8.7mm to the back side of inner circumferential sealing surface 21 apart from HB.Thus, the inner circumferential sealing surface of valve seat bush 21 wall thickness is 3mm.In this case, it is provided with clearance portion G between valve body 3 and valve seat bush 11.This clearance portion G is in valve closing Shi Chengwei is by the protrusion described later 37 in the Inner peripheral portions of the support rubber 4 being pushed via valve seat bush 11 by valve disc 2 at it The space of adjacent position storage.

As Fig. 6（b）Shown, if not having attaching valve disc 2 to be arranged on valve by being provided with the valve seat bush 11 supporting rubber 4 In the case of on body 3, by the elastic force supporting rubber 4, valve seat bush 11 necking deformation, the internal diameter of this inner circumferential sealing surface 21, i.e. In the sealing 12c crimping sealing of so-called valve disc 2, the internal diameter φ d2 in high portion 45 is φ 97.4 from φ 100mm undergauge.This When, become from 11.7mm apart from HA1 from the bottom surface of attaching slot 35 to inner circumferential sealing surface 21 and turn to 13mm, but valve seat bush 11 is interior The wall thickness of all sealing surfaces 21 maintains 3mm.

In addition, when by supporting rubber 4 to be installed on valve body 3, due to attaching slot 35 as described above depth ratio this The thickness T of support rubber 4 is shallow, so supporting rubber 4 to inner circumferential side inner circumferential sealing surface with valve seat bush 11 in the state of prominent 21 back side abuts, and is provided with clearance portion G between this valve seat bush 11 and valve body 3.That is, clearance portion G is for above-mentioned clearance portion G The valve seat bush 11 adding undergauge is for being restored to Fig. 6（a）State space.

In figure 3, the valve body 1 of valve disc 2 is installed on via the valve body 3 supporting rubber 4 to be provided with valve seat bush 11 In the case of, according to the rotation status of valve disc 2, different with the internal diameter of valve seat bush during valve closing 11 in valve opening.In valve opening, pass through To undergauge direction deformation under the elastic force supporting rubber 4, in valve seat bush 11, the internal diameter in high portion 45 is deformed into as described above Less than valve disc external diameter φ D1, become Fig. 6（b）State internal diameter φ 97.4mm.On the other hand, during valve closing shown in Fig. 3, lead to Crossing valve disc 2 opposing supports the elastic force of rubber 4 to carry out urging valve seat bushing 11, and in valve seat bush 11, the internal diameter in high portion 45 passes through valve disc Pushing and be restored to the internal diameter before deforming, the internal diameter φ d1 before this deformation is and Fig. 6（a）State identical valve disc external diameter φ D1 identical φ 100mm.Now, from the bottom surface of attaching slot 35 to inner circumferential sealing surface 21 be about 11.7mm apart from HA, from dress Access slot 35 bottom surface is about 8.7mm to the back side of inner circumferential sealing surface 21 apart from HB.Thus, the inner circumferential sealing surface of valve seat bush 11 Wall thickness 3mm on 21 is maintained.

So, the valve disc 2 urging valve seat bushing 11 in valve closing, when carrying out valve base sealing, high portion in valve seat bush 11 45（Inner circumferential sealing surface 21）Simply return to not have attaching support rubber 4 state, i.e. the formation of valve seat bush 11 when size, and It is not compressed, so not remaining permanent strain on valve seat bush 11 and keeping good inner circumferential sealing surface 21, can be persistently long Phase maintains higher seat leakage.

And, the torque needing when valve closing operates only from make power from support rubber 4 to expanding direction elastic deformation produce, So operation torque is substantially reduced, can continue to maintain for a long time the operation torque of this reduction.

And, these features do not depend on the wall thickness of valve seat bush 11, for example make wall thickness thickening to 4mm about or such as Fruit be exceed nominal diameter 125A the larger butterfly valve of bore then wall thickness is set as 5mm within it is also possible to maintain higher Seat leakage, low torque.

The side face sealing position being formed in the inner circumferential sealing surface 21 of the valve alar part 20 by above-mentioned valve disc 2 and valve body 3, in Fig. 7 In, in the case of making valve disc 2 from closed state to the rotation of valve opening side, in this valve disc 2 with valve wing difference S range of rotation（It is provided with The scope in middle high portion 45）Interior, be formed as and this inner circumferential sealing surface 21 identical broad-ruler by supporting rubber 4 as described above Very little, play the elastic force of this support rubber 4 it is ensured that high leakproofness.In the scope of this valve wing difference S, also same with above-mentioned situation Prevent the compression of valve seat bush 11 it is ensured that sealing and operation torque.

In the case of which kind of valve closing sealing, when in valve closing, the internal diameter before the interior radial deformation of valve seat bush 11 is multiple When former, support rubber 4 with expanding and protrusion 37 that swell in the direction of the width all deform with squeeze flat to being located at valve body 3 and valve In clearance portion G between seat pad set 11, received by this clearance portion G.Therefore, play impartial pushing sealing force throughout circumference, It is able to maintain that do not have excessive sealing state.

Here, represent the comparative example being used for comparing with the seal construction of the butterfly valve of the present invention in Fig. 10.This valve seat serves as a contrast Set 50 is in Figure 10（a）If in do not have attaching support rubber 4, valve disc 2 state be arranged on valve body 3 in the case of, if Be from the bottom surface of attaching slot 35 to the back side of inner circumferential sealing surface 51 apart from HC be 10mm, the internal diameter φ dA1 of inner circumferential sealing surface 51 Shape as φ 97.4mm.Thus, though in attaching slot 35 attaching thickness 10mm support rubber 4, also will not be from this Rubber 4 is supported to apply the power of undergauge direction.

In Figure 10（b）In, by this valve seat bush 50 via supporting in the case that rubber 4 is arranged on valve body 3, by The elastic force of support rubber 4, valve seat bush 50 necking deformation, the internal diameter of its inner circumferential sealing surface 51 is by undergauge.And, fill on valve body 3 Connect valve disc 2, in valve opening, the internal diameter φ dA2 making inner circumferential sealing surface 51 than φ 97.4mm undergauge, in valve closing, by valve disc 2 Push, the size of this valve disc external diameter φ D1 is by expanding to φ 100mm.

So, the feelings of the valve seat bush 50 less than valve disc external diameter φ D1 of the internal diameter φ dA1 before the deformation being brought by valve disc 2 Under condition, when valve disc 2 rotation becomes closed valve state, in addition to the pushing deformation supporting rubber 4, there is additionally required and so that valve seat is served as a contrast Set 50 compresses, that is, reduces the thickness of valve seat bush 50 and make the power of its elastic deformation.And, it is thickening with this valve seat bush 50, The power of compression also becomes big, proportional to the thickness of valve seat bush 50, and operation torque also increases.But, due in operation torque There is the limit allowed, so being difficult to the thickness of valve seat bush 50 is set as the size of more than certain degree.On the other hand, if Make the lower thickness of valve seat bush 50, then because resistance to through performance declines, so being difficult to meet chemical resistance and the thermostability of needs.

In addition, the butterfly valve of nominal diameter 100A of actual measurement present embodiment and the identical nominal diameter being equivalent to Figure 10 The valve closing operation of butterfly valve when torque capacity after confirm, the butterfly valve of present embodiment is with respect to being equivalent to the identical of Figure 10 The torque that the butterfly valve of nominal diameter is capable of about 23% reduces.

Then, in the axle envelope sealing position of the valve rod 5 of valve seat bush 50, such as Fig. 9（b）As shown in set at a proper angle Put the periphery conical surface 60 of the periphery end of each axle charging tube part 42, by this periphery conical surface 60, axle charging tube part 42 is formed as chock shape, The base portion 64 of this axle charging tube part 42 is set to than the periphery conical surface 60 wall thickness.And then, the height of axle charging tube part 42 arranges comparatively short. By such shape, when being applied with external force from peripheral direction on the periphery conical surface 60, only this periphery conical surface 60 nearby deforms, By preventing the deformation near the root of axle charging tube part 42, be formed in the inner circumferential of axle charging tube part 42 as valve rod patchhole Valve shaft hole 13 will not deform and ensure that its out of roundness.

In the inner circumferential of each axle charging tube part 42, it is provided with the prominent shape sealing 61 of the ring-type projecting to inner circumferential side, this prominent shape is close Envelope portion 61 can crimp the periphery Shangdi setting being sealed in liner cylindrical portion 26.Thus, the sealing near this prominent shape sealing 61 Power uprises, and prevents the leakage between axle charging tube part 42 and liner cylindrical portion 26.

In the outer circumferential side of axle charging tube part 42 base portion, depression is formed with ring-type groove portion 62, and axle charging tube part 42 is formed as, via this Ring-type groove portion 62 is more protrusively provided than annulus 40.By arrange ring-type groove portion 62, applying power on valve seat bush 11 and In the case of making annulus 40 and flange part 41 be deformed into generally elliptical shape on the attaching direction of top and the bottom valve rod 5a, 5b, Axle charging tube part 42 is not easy to be affected by, and prevents from deforming.

In Fig. 4, Fig. 5, above-mentioned seal sleeve 30 as shaft sealing part 17, seal member 31, disc spring 32, plate member In the 33 each attaching recesses 29 being installed in top and the bottom valve body 3a, the 3b being covered by above-mentioned valve seat bush 11, divide in its inner circumferential Other plug-in mounting is positioned holding in the state of top and the bottom valve rod 5a, 5b.Bearing 34 is in the attaching recess with top and the bottom valve body 3a, 3b 29 eccentric positions compared, can respectively from ring-type groove portion 62 side be located at clamping top and the bottom valve rod 5a, 5b and axle dress hole 28 it Between.By this bearing 34, the rotation of top and the bottom valve rod 5a, 5b becomes smooth.

Disc spring 32 is for example arranged to the external diameter being attached in attaching recess 29 by the spring steel implementing surface treatment, The ratio seal sleeve 30 being disposed in attaching recess 29 is by being centrifuged the position of side.Between disc spring 32 and seal sleeve 30, for example by Rustless steel is provided with flat annular plate part 33, and via this plate member 33, the pushing force of disc spring 32 is by seal sleeve 30 Upper surface side Transmit evenly, above-mentioned upper-lower seal（Once sealing）Function.

Seal sleeve 30 is for example by carbon containing PTFE（Politef）Be formed as being attached to attaching recess Deng fluororesin Substantially a ring-shaped in 29, by with valve seat bush 11 directly contact in the way of be installed in attaching recess 29.In seal sleeve 30 It is formed with the inner circumferential conical surface 63 with the inner circumferential lower side of the opposed locations of the periphery conical surface 60, these inner circumferential conical surfaces 63 and the periphery conical surface 60 It is set to identical tilt angle theta with respect to vertical, the abutting contacting by face is crimping sealing.In the present embodiment, this The tilt angle theta of a little inner circumferential conical surfaces 63 and the periphery conical surface 60 is set to 20 °, when applying to push from disc spring 32 to seal sleeve 30 During power, by the chock effect brought by these inner circumferential conical surfaces 63 and the periphery conical surface 60, the direction in valve rod footpath produces by point The pushing force that power is brought, makes axle charging tube part 42 touch with liner cylindrical portion 26 by this pushing force, by this liner cylindrical portion 26 with Valve rod 5 outer peripheral face touches, sealing（Secondary seal）Function.And then it is also possible to set in the inner circumferential side of liner cylindrical portion 26 Put ring-shaped protrusion (not shown), in the case, it is possible to increase the face pressure of sealing.

Attaching seal member 31 between the liner cylindrical portion 26 of seal sleeve 30 and inner circumferential upper side.Seal member 31 by The metal coil spring 65 being formed with corrosion-resistant metal and the cap assembly 66 of the ring-type being formed with fluororesin are constituted, coil Spring 65 is embedded in integrated in the attaching groove 67 of the ring-type being formed on cap assembly 66.By this structure, sealing Part 31 is arranged to, and while make up the low elastic force of fluororesin with the elastic force of coil spring 65, can play in radiation direction Resilient sealing force, the elastic force by coil spring 65 in low pressure, the elastic force by fluid pressure and coil spring 65 in high pressure, Play higher sealing force respectively.

By this seal member 31, close with the periphery conical surface 60 of axle charging tube part 42 in the inner circumferential conical surface 63 making seal sleeve 30 While connecing, liner cylindrical portion 26 inner circumferential side is made to touch with valve rod 5 outer peripheral face, sealing（Three sealings）Function, true Protect chemical resistance and to while the toleration of superhigh temperature ultralow temperature it is ensured that top and the bottom valve rod 5a, 5b rotation when dynamic Sealing.In addition, in order to ensure the position of this seal member 31 and three sealings of liner cylindrical portion 26, needing liner cylindrical portion 26 length reaches this position, is determined by the length of this liner cylindrical portion 26.

Seal member 31 its peristome 31a of present embodiment configures towards the foreign side of valve disc 2.Thus, even if contingency Above-mentioned once sealing, the hydraulic performance decline of secondary seal and fluid reach seal member 31, the coil spring 65 of seal member 31 Will not contact with liquid and maintain three sealing functions.The configuration direction of such seal member 31 is especially being disposed metal corruption It is effective in the case of the higher liquid of probability of erosion.

As shown in figure 5, between the axle charging tube part 42 of seal sleeve 30 and valve seat bush 11, be formed with the 1st space part 71, 2nd space part 72.By arranging these the 1st space part 71, the 2nd space parts 72, when valve disc 2 is to the attaching of valve body 3 when in order to When improving sealing power and making the fastening force of valve body 3 become strong, apply stronger pushing from the lateral valve seat bush 11 of valve disc liner 12 Power, makes the material of the inner liner 10 of deformation avoid.Specifically, the 1st space part 71 is for making the axle charging tube part 42 of deformation, interior The space that lining cylindrical portion 26, the material of seal sleeve 30 avoid, the 2nd space part 72 is for making the seal sleeve 30 of deformation, axle The space that the material of charging tube part 42 avoids.By arranging these the 1st space part 71, the 2nd space parts 72, sealing position pressure each other Relay will not be raised to more than required, plays higher sealing while suppression operation torque.

Due to being respectively equipped with the 1st space part 71, the 2nd space part 72 between valve seat bush 11 and seal sleeve 30, so When being applied with stronger pushing force by disc spring 32, the material of deformation avoids, and resistance during rotation is alleviated, and operation torque subtracts Little.And then, can prevent part injury or deformation, fracture, remain higher close at the axle envelope sealing position of both sides of upper and lower sides Feng Xing.

As described above, in the seal construction of valve body 1, the internal diameter of the valve seat bush 11 during valve opening is supporting rubber 4 Elastic force under be deformed into ratio valve disc external diameter φ D1 path, the internal diameter φ d1 of the valve seat bush 11 during valve closing is to support rubber 4 It is deformed into the internal diameter before path under elastic force, be set to by the internal diameter φ d1 before deforming this identical with valve disc external diameter φ D1（Bag Containing tolerance）Or than valve disc external diameter φ D1 big slightly footpath, will not sealing from valve disc 2 periphery apply make valve seat when valve closing seals The power of bushing 11 compression, it is possible to prevent from operating the rising of torque while guaranteeing high leakproofness.And, increased tree It is also possible to not applying to make power that this inner liner 10 compresses and operating and seal shape for valve closing in the case of the thickness of fat inner liner 10 State, it is possible to be easily opened and closed operation with certain relatively low operation torque.

In the case, inner liner 10 is arranged by fluororesin, thus will close while improving chemical resistance and thermostability Valve operation when operation torque suppress relatively low, can suppress valve disc 2 sealing when abrasion and deterioration, improve durability.

In addition, in the present embodiment, the internal diameter φ d1 of the inner circumferential sealing surface 21 of valve seat bush 11 is set as and valve disc External diameter φ D1 identical φ 100mm, but have respectively in each part ± 0.1mm about machining tolerance.

Thus, such as

It is φ 99.9mm with respect to the external diameter φ D1 of valve disc 2, the internal diameter φ d1 of the inner circumferential sealing surface 21 of valve seat bush 11 is φ 100.1mm

It is φ 100.1mm with respect to the external diameter φ D1 of valve disc 2, the internal diameter φ d1 of the inner circumferential sealing surface 21 of valve seat bush 11 is φ 99.9mm

Like that, the internal diameter φ d1 of the inner circumferential sealing surface 21 of valve seat bush 11 situation roughly the same with the external diameter φ D1 of valve disc 2, It is that valve seat bush 11 will not be comprised in the present invention by the construction of compression seal when valve closing seals.

Additionally, the internal diameter being φ 100mm, the inner circumferential sealing surface 21 of valve seat bush 11 as the external diameter φ D1 with respect to valve disc 2 For φ 102mm like that, the internal diameter φ d1 of the inner circumferential sealing surface 21 of valve seat bush 11 bigger by 2% about slightly than the external diameter φ D1 of valve disc 2 The situation in slightly larger footpath, be also when valve closing seals valve seat bush 11 will not be comprised in the present invention by the construction of compression seal.

If the internal diameter φ d1 of valve seat bush 11 be value during the big footpath than the external diameter φ D1 of valve disc 2 more than 2%, valve seat serves as a contrast The change that set 11 is deformed into diameter before and after path under the elastic force supporting rubber 4 becomes big, it is possible to showing in durability Now affect.

Thus, from the viewpoint of the durability of the sealing guaranteeing with valve disc 2 and valve seat bush 11, valve seat bush 11 exists Support the internal diameter φ d1 being deformed into before path under the elastic force of rubber 4 preferably roughly the same with valve disc external diameter φ D1.This reality As long as apply the internal diameter φ d1 before the above-mentioned deformation of the valve seat bush 11 of mode be set as 99.9% with respect to valve disc external diameter φ D1～ 102% is just permissible, is more preferably set to 100%～102% just permissible.

Then, the manufacture method of above-mentioned valve body 1 is described.

Above-mentioned valve body 1 can by through deformation operation, to core operation, cylindrical portion insert operation, valve rod connect operation, Valve body integration operation, valve rod positioning process and formed.

In fig. 11, representing first, can make the above-mentioned valve seat bush 11 of the valve disc 2 periphery side seal shown in Figure 12 This valve seat bush 11 deforms in deformation operation.

In Figure 13, Tu14Zhong, represent the state making valve seat bush 11 deformation by external force, by applying under normal temperature state External force and be morphed into ellipse.Before applying this external force, as shown in figure 13, make valve disc 2 rotate to full-gear, connect , apply external force when, make the periphery of valve seat bush 11 parallel with the flange part 41 of this valve seat bush 11, and from axle fitted tube The back side of the inner circumferential sealing surface 21 of valve seat bush 11 is clipped between the nip part 90 of vice by the direction that the shaft core in portion 42 is orthogonal Push so as to the direction being deformed into axle charging tube part 42 is oval as long side.

In the case, push from foreign side, so that being deformed into the length of the inner circumferential sealing surface 21 of elliptoid valve seat bush 11 Side R1 is longer than total length R2 of the liner cylindrical portion 26 including valve disc 2.

The handss that this push-press working is also used as dealer are directly carried out, but it is preferred that using vice or bench vice（vice）Deng Valve seat bush can be remained elliptoid device.By so valve seat bush 11 being remained ellipticity, described later to core With valve disc 2, easy is become to core operation during operation.

As the size of the power applying to valve seat bush 11 when pushing, for being able to maintain that the shape of the elastic force of valve seat bush 11 State, specifically, the releasing by pushing as described later can be restored to positive round or the state close to positive round from ellipse Power, the so-called scope being capable of elastic deformation.Valve seat bush 11 does not need to be entirely positive round before assembling, as long as being encased in valve Become round type just permissible in body 3 and after valve body 1 is set.

As described above, by forming shorter axle charging tube part 42, the periphery conical surface 60 is arranged on this axle charging tube part 42 And so that the base portion 64 of axle charging tube part 42 is become more thickened wall, be additionally provided with ring-type groove portion 62, when clipping valve rod with nip part 90 Prevent the deformation in valve shaft hole 13, maintain its out of roundness.

Then, in core operation, valve seat bush 11 inner circumferential of the state of deformation loads valve disc 2.Now, protect Hold the position of valve disc 2 so that the shaft core of the axle charging tube part 42 of the shaft core of liner cylindrical portion 26 of valve disc 2 side and valve seat bush 11 side Parallel and valve disc 2 is identical with the distance of the open side in upper and lower each valve shaft hole 13, make valve disc 2 move to valve seat bush 11 inner circumferentials, by the shaft core of liner cylindrical portion 26 and axle charging tube part 42 to core.In addition, now can also be in advance in valve shaft hole 13 Insert columned fixture (not shown), with this fixture, valve shaft hole 13 is strengthened from inner circumferential.The length of this fixture is than top and the bottom valve Bar 5a, 5b are short.

After to core operation, in cylindrical portion insertion operation, the external force to valve seat bush 11 is gradually weakened.Thus, Valve seat bush 11 automatically restores to round type from ellipticity under its elastic force, in fig .15, by valve disc 2 is upper and lower Liner cylindrical portion 26 be inserted into constitute valve rod hole axle charging tube part 42 in while valve disc 2 is attached on valve seat bush 11, justify Cylinder portion insertion operation completes.Thus, the state being supported by the axle charging tube part 42 of valve seat bush 11 in the liner cylindrical portion 26 of valve disc 2 Under, the blocking in the state of can connecting top and the bottom valve rod 5a, 5b by valve disc 2 and valve seat bush 11.Alternatively, it is also possible in valve Gap is set between the upper and lower sides of disk 2 and valve seat bush 11, passes through valve body integration process step combinations Fig. 5 described later in the gap Shown shaft sealing part 17, thus constitutes the sealing position of valve disc 2 upper and lower sides.

Connect in operation in valve rod, in figure 16, by the connecting portion 25 of top and the bottom valve rod 5a, 5b end side by shaft core Be aligned gradually inserts to valve rod hole portion 24 on one side, and these top and the bottom valve rod 5a, 5b are connected with valve disc 2.Top and the bottom valve rod 5a, On 5b, it is provided with conical surface portion 91 between the boundary member of cylindric position and connecting portion 25, upper lower valve is prevented by this conical surface portion 91 Bar 5a, 5b to valve disc 2 insertion when liner cylindrical portion 26 damage.

In the insertion of these top and the bottom valve rod 5a, 5b it is possible to accumulate empty in valve rod hole portion 24 with this insertion Gas, but can by this air between top and the bottom valve rod 5a, 5b and liner cylindrical portion 26 dissipation.

In valve body integration operation, will the company of being built-in with top and the bottom valve body 3a, the 3b shaft sealing part 17 with attaching Then in the state of the valve seat bush 11 of the valve disc 2 of top and the bottom valve rod 5a, 5b sandwiches, by top and the bottom valve rod 5a, 5b and valve disc 2 Connect and can be integrated by top and the bottom valve body 3a, 3b with this top and the bottom valve rod 5a, 5b by the state of valve disc 2 rotation process.

In detail, first, attaching shaft sealing part 17 in the attaching recess 29 of top valve body 3a in advance.Now, from The inboard of the attaching recess 29 of bearing 34 is installed, arranges disc spring 32, seal member 31, plate member 33, seal sleeve 30 successively.

On the top valve body 3a that shaft sealing part 17 in such attaching, load be built-in be connected to top and the bottom valve rod 5a, The valve seat bush 11 of the valve disc 2 of 5b.Thus, the first half of valve seat bush 11 is loaded in the valve body 3a of top.

On the other hand, for bottom valve body 3b, also same with top valve body 3a, in attaching recess 29, attaching axle is close in advance Envelope part 17.

In this case, the lower half side of the valve seat bush 11 being loaded in the valve body 3a of top is encased in bottom valve body 3b In, become state valve seat bush 11 being sandwiched by these tops valve body 3a and bottom valve body 3b.

In this case, threaded connection bolt 27 in the bolt hole 36 of top and the bottom valve body 3a, 3b as shown in Figure 2, Top and the bottom valve body 3a, 3b are interfixed.Thus, top and the bottom valve body 3a, 3b are fastened on threaded direction, disc spring 32 quilt Compression, acts on seal sleeve 30 by the pushing force of above-mentioned disc spring 32, the valve seat bush 11 of the upper and lower sides of valve disc 2 and valve disc 2 upper-lower seal as once sealing, axle charging tube part 42 inner circumferential are closely contacted on this liner cylinder on liner cylindrical portion 26 periphery The sealing as secondary seal of portion 26 and the contiguity sealing of valve rod 5 outer peripheral face and the conduct that brought by seal member 31 three times The sealing of sealing, is combined ground function at the axle dress position of top and the bottom valve rod 5a, 5b, by the sealing work(of above-mentioned valve flank Can play with being superimposed together with this axle envelope sealing function, can by the sealing on the whole side face of valve disc 2 after assembling higher Guarantee.

In valve rod positioning process, by top valve rod 5a, bottom valve rod 5b are positioned with the state that can rotate respectively It is fixed on top valve body 3a, bottom valve body 3b, prevent flying out of they.

In fig. 2, for top valve rod 5a, via dust-proof O-ring 80, thrust washer 81, c-type back-up ring 82 attaching. In the case, in the state of top valve rod 5a is inserted in valve disc 2, in this position of the upper periphery of this top valve rod 5a Put attaching O-ring 80, thrust washer 81, from their top, c-type back-up ring 82 is engaged with top valve rod 5a.In this condition, The cover clamp covering via thrust washer 81 configuration of the top of c-type back-up ring 82（grand plate）83, by this cover clamp 83 Fixed from the top of valve body 1 with screw element (not shown).By such assembling top valve body 3a side, can arrange by via pushing away The anti-construction that flies out of the top valve rod 5a of the c-type back-up ring 82 of power packing ring 81 and cover clamp 83 formation.

For bottom valve rod 5b, via O-ring 80, thrust washer 81, covering end plate 84 attaching.In the case, exist The periphery attaching O-ring 80 of thrust washer 81, will be attached in thrust washer 81 in the axle dress hole 28 being formed on the valve body 3b of bottom, Arranged opposite with the valve foreign side side end face of bottom valve rod 5b.In this case, with end plate 84, axle is filled hole 28 to block, by this end plate 84 are fixed from the lower section of valve body 1 with affixed bolt 85.Thus, the axle of bottom valve rod 5b side installs into.

Additionally, in the case that valve body 1 is decomposed, can as long as being implemented with the order contrary with the situation of above-mentioned assembling With.In the case, as long as after pull down top and the bottom valve body 3a, 3b from valve seat bush 11, as follows by valve seat bush 11 decomposition are just permissible.

In the top and the bottom of valve seat bush 11, from this valve seat bush 11, seal sleeve 30 is gradually extracted and pull down.Will be upper In the case that lower valve rod 5a, 5b pull down, lower valve rod 5a, 5b on these are held respectively, on one side gradually from the valve shaft of valve disc 2 Hole 13 is extracted successively.

After the extracting of upper lower valve rod 5a, 5b, so that valve disc 2 is rotated, become the state of fully open position as shown in Figure 13, Make the flow path portion periphery of valve seat bush 11 parallel with flange part 41, and push from the shaft core orthogonal direction with axle charging tube part 42, It is oval as long side for being morphed into this axle charging tube part 42 direction.Continue this pushing, until being deformed into elliptoid valve seat The long side of bushing 11 exceedes the height of valve disc 2, makes the shaft core of axle charging tube part 42 parallel with the shaft core of liner cylindrical portion 26, and, While making the height of valve disc 2 and distance each other becomes identical degree, gradually by valve disc 2 from valve seat to axle charging tube part 42 Bushing 11 is pulled down.Can decompose as above.

As described above, apply external force to valve seat bush 11 under normal temperature state and be morphed into elliptoid state Under, to load valve disc 2 to this valve seat bush 11 inner circumferential to wick-like state, make valve seat bush 11 be restored to round type from ellipticity, So that liner cylindrical portion 26 is inserted in axle charging tube part 42, valve disc 2 is attached on valve seat bush 11, then, by top and the bottom valve rod The connecting portion 25 of 5a, 5b gradually inserts to the valve rod hole portion 24 of valve disc 2 and connects them, shaft sealing part 17 with attaching The valve seat bush 11 being built-in with valve disc 2 is sandwiched and integrated by top and the bottom valve body 3a, 3b, to manufacture valve body 1, thereby, it is possible to While so that the sealing near the boss portion 15 of valve seat bush 11 is improved, prevent valve seat bush 11 and the resin coating of valve rod 5 The damage of cap easily attaching valve disc 2 are assembling.And, with regard to apportioned effort it is also possible to assembling situation equally simple Singly implement.

In the case, it is deformed into ellipticity, pushes so that this valve seat bush 11 from foreign side by making valve seat bush 11 The long side R1 of inner circumferential sealing surface 21 is longer than total length R2 of valve disc 2, can be reliably prevented what valve disc 2 was contacted with valve seat bush 11 Meanwhile, dismount valve disc 2 to guarantee the axle envelope sealing near boss 15 with respect to valve seat bush 11.

Claims

1. a kind of seal construction of butterfly valve, on valve disc surface with via the valve body supporting rubber can rotate ground axle suspension valve disc Inner peripheral surface on be respectively provided with the inner liner being made up of resin material, and be located at the valve seat bush as valve body sidelining layer Diametric(al) opposed locations at valve shaft hole axis dress valve rod, when by this valve rod rotation process up to major general's valve disc valve alar part Crimping be sealed on valve body inner peripheral surface it is characterised in that

The internal diameter of above-mentioned valve seat bush sets as follows：In valve opening, the internal diameter of above-mentioned valve seat bush is in the elastic force of above-mentioned support rubber It is deformed into the internal diameter being in a ratio of path with the external diameter of above-mentioned valve disc, on the other hand, above-mentioned valve disc pushes in valve closing, becomes under effect It is the internal diameter under the elastic force effect of above-mentioned support rubber to before path deformation, the internal diameter before this is deformed is set to comprise tolerance Identical with above-mentioned valve disc external diameter or more slightly larger than valve disc external diameter.

2. butterfly valve as claimed in claim 1 seal construction it is characterised in that

By the thickness of above-mentioned support rubber is set to the width dimensions of this support rubber substantially with size or than this support rubber The width dimensions of glue are slightly long, easily the internal diameter of above-mentioned valve seat bush are restored to the internal diameter before above-mentioned deformation in valve closing.

3. butterfly valve as claimed in claim 1 or 2 seal construction it is characterised in that

When internal diameter before radially deformation being stated in above-mentioned valve seat bush when in valve closing restores, by above-mentioned support rubber with Protrusion that is expanding and swelling in the direction of the width is received in the clearance portion being located between above-mentioned valve body and above-mentioned valve seat bush.

4. the butterfly valve as any one of claims 1 to 3 seal construction it is characterised in that

The width of above-mentioned support rubber is set to the size roughly the same with the valve wing difference of above-mentioned valve disc.

5. the butterfly valve as any one of Claims 1 to 4 seal construction it is characterised in that

Above-mentioned inner liner is fluororesin.

6. the butterfly valve as any one of Claims 1 to 5 seal construction it is characterised in that

The conical surface of predetermined angular is set in two surface sides of the valve flank end of the valve disc liner as above-mentioned valve disc sidelining layer, Form the sealing crimping sealing with above-mentioned valve seat bush between these conical surfaces, the width of this sealing is set to and above-mentioned valve disc Arbor end side the roughly the same size of width.