CN209483729U - Hydraulic-driven axial flow valve - Google Patents

Abstract

The utility model provides hydraulic-driven axial flow valve, belong to valve field, valve body and spool including coaxial arrangement, the valve body includes inlet and outlet, directed cavity is equipped with close to one end of the water outlet in the valve body, it is fixedly installed between the directed cavity and the inner wall of the valve body by dowel, the directed cavity is stifled equipped with tail close to the sealing of one end of the water outlet, one end of the spool, which is located in the directed cavity, and the two is sealed is slidably connected, the other end of the spool and the water inlet are equipped with the opening and closing for controlling the water inlet.The utility model spool is arranged concentrically with valve body, substantially reduces vibration and noise caused by turbulent flow, and body cavity is streamlined using leading directly to, and greatly reduces flow resistance.

Description

Hydraulic-driven axial flow valve

Technical field

The utility model belongs to valve field, is related to hydraulic-driven axial flow valve.

Background technique

Axial flow valve, that is, axial flow type check valve is a kind of a kind of component on the medium pipeline of one-way flow, it belongs to One kind of automatic valve, on the outlet of oil, gas and various defeated pump for pipe systems and other places, we can see this fire-fighting and stone Makeup is set.When it is installed on pipeline, maximum effect is exactly in order to prevent medium from flowing in the opposite direction, to a certain degree On prevent the generation of accident, axial flow type check valve currently on the market runs smoothly, fluid resistance also very little, also there is low noise The features such as sound and very strong leakproofness.

In hydraulic medium transmission process, pipeline can bear negative pressure, during conveying, it is also possible to generate turbulent flow shake It is dynamic, transfer pipeline is caused to damage.

Utility model content

Problem to be solved in the utility model is to be to provide hydraulic-driven axial flow valve, and spool is arranged concentrically with valve body, greatly Big to reduce vibration and noise caused by turbulent flow, body cavity is streamlined using leading directly to, and greatly reduces flow resistance.

In order to solve the above technical problems, the technical solution adopted in the utility model is: hydraulic-driven axial flow valve, including it is coaxial The valve body and spool of setting, the valve body include inlet and outlet, and one end in the valve body close to the water outlet is set There is directed cavity, be fixedly installed between the directed cavity and the inner wall of the valve body by dowel, the directed cavity is close to described One end sealing of water outlet is stifled equipped with tail, and one end of the spool, which is located in the directed cavity, and the two is sealed is slidably connected, The other end of the spool and the water inlet are equipped with the opening and closing for controlling the water inlet.

Further, the valve body includes intermediate straightway, the introduction segment of the close water inlet and goes out described in The equal arc gradual change of the relatively described straightway of internal diameter of the export section at the mouth of a river, the introduction segment and export section is gradually reduced and final defeated It is out the fixed diameter of linear, the introduction segment is equipped with chamfering far from one end of the water outlet.

Further, the internal diameter of the introduction segment is the 7/10 of the straightway internal diameter, and the wall thickness of the introduction segment is greater than The wall thickness of the straightway, the outer diameter of the introduction segment are equal to the internal diameter of the export section, and the wall thickness of the export section is less than etc. In the wall thickness of the straightway.

Further, the introduction segment is equipped with positioning convex platform close to one end of water inlet, sets on the inner cavity of the introduction segment There is sealing filament ring, one end and the positioning convex platform of the sealing filament ring are equipped with, and the other end extend into the introduction segment Internal to be equipped with the valve, the outer ring of the sealing filament ring matches setting, the positioning with the inner ring of the introduction segment The first O-ring is equipped between boss and the sealing filament ring, the sealing filament ring is equipped with far from the inner ring of described inlet port one end Sealing ring.

Further, the length of the directed cavity is greater than the 1/2 of the length of straigh line of the valve body, the directed cavity outer ring One end end face from close to described water inlet one end to close to the water outlet is gradually reduced and slope is 2.2~3.2 degree.

Further, the quantity of the dowel is five and length is identical as the length of the directed cavity, described in five The axis of the relatively described directed cavity of dowel is uniformly arranged, and the junction of the dowel and the directed cavity is equipped with the first circle The inner wall junction of angle, the dowel and the valve body is equipped with the second fillet, the radius of first fillet and described second The radius of fillet is identical.

Further, the directed cavity is equipped with exhaust passage hole and medium with external connection close to one end that the tail blocks up Access opening, the exhaust passage hole and dielectric channel hole are each provided on the dowel, and the exhaust passage hole is set by matching The sealing silk plug set realizes opening and closing, is equipped with the second O-ring between the sealing silk plug and the valve body, the dielectric channel hole and Spool is driven to be connected to respect to the hydraulic-driven component of valve body.

Further, the hydraulic-driven component includes hydraulic conversion cylinder, the hydraulic conversion cylinder by water pipe with it is described Dielectric channel hole connection, the hydraulic conversion cylinder realize movement by the oil cylinder that hydraulic station drives.

Further, the spool includes valve rod, and the valve rod is equipped with whale core close to one end of the water inlet and moves head, separately One end is equipped with piston, and the piston is located in the directed cavity and the two is slidably connected, the outer ring of the piston and the guiding It is equipped with multiple third O-rings disposed in parallel between the inner wall of chamber, is additionally provided on the valve rod disposed in parallel with the piston Guide pad, it is dynamic between the piston that the guide pad is located at the whale core, the guide pad be located at the directed cavity it is interior and with The directed cavity is slidably connected, and the valve rod is hollow bar structure.

Further, it is shell-like structure that the whale core, which moves head, and the whale core moves the sealing and branch that head includes circular sliding slopes The opening and closing of the water inlet is realized in the inner wall cooperation of support part, the sealing and the valve body, and the support portion is located at described close The one end of envelope portion far from the water inlet, the support portion are coaxially disposed with open circles taper and with the valve rod, the support Portion is gradually reduced from the water inlet to the section of the water outlet and slope is 2.5~3.5 degree, in the retraction shape of the valve rod Under state, the support portion is bonded setting with the section of the directed cavity, and in bonding position, the outer diameter of the support portion is led with described Outer diameter to chamber is identical.

Compared with prior art, the utility model has the advantage that as follows with good effect.

1, the utility model spool and valve body are arranged concentrically, and substantially reduce vibration and noise, body cavity caused by turbulent flow It is streamlined using leading directly to, greatly reduce flow resistance；

2, the equal arc gradual change of the relatively straight line segment of internal diameter of introduction segment and export section is gradually reduced and final output is linear Fixed diameter, under opening state, after medium enters valve inner, pressure reduces, and avoids causing the inner wall of valve body larger Impact, the stability of lift structure；

3, the outer diameter of introduction segment is equal to the internal diameter of export section, is conducive to the quick outflow of medium, to a certain extent further Impact of the medium to valve body and spool, the stability of lift structure are reduced, the wall thickness for exporting section is less than or equal to the wall of straightway Thickness under the premise of not influencing intensity, saves material, reduces cost；

4, the slope of directed cavity outer ring is consistent with the slope of support portion on the dynamic head of whale core, under valve opening state, guiding The outer ring of chamber and whale core move head, are shrunk to complete " whale core ", and meticulously dynamic head is consistent with the outer ring slope of directed cavity forms one Streamline, streamline is very good, the structure of similar whale, and medium passes through out from water inlet by being connected a plurality of cavities that muscle separates Mouth of a river discharge, inlet and outlet coaxial arrangement, and also valve body is full-bore, will not generate turbulent flow vibration；

5, exhaust passage hole is set, when being filled with hydraulic medium for the first time, it is necessary to open the exhaust silk above exhaust passage hole It is stifled, the air in directed cavity is emptied, guarantees the movement travel of piston, dielectric channel hole is set, connect, has with hydraulic-driven component Help realize the reciprocating motion that piston is stable.

Detailed description of the invention

The attached drawing for constituting a part of the utility model is used to provide a further understanding of the present invention, this is practical new The illustrative embodiments and their description of type are not constituteed improper limits to the present invention for explaining the utility model.? In attached drawing:

Fig. 1 is the complete section schematic diagram under the utility model hydraulic-driven axial flow valve closed state；

Fig. 2 is the complete section schematic diagram under the utility model hydraulic-driven axial flow valve opening state；

Fig. 3 is the portion the A detail drawing of the utility model Fig. 1；

Fig. 4 is the portion the B detail drawing of the utility model Fig. 1；

Fig. 5 is the portion the C detail drawing of the utility model Fig. 1；

Fig. 6 is the portion the D detail drawing of the utility model Fig. 1；

Fig. 7 is the front view of the utility model valve body；

Fig. 8 is the E-E cross-sectional view of the utility model valve body；

Fig. 9 is the cross-sectional view of the utility model spool；

Figure 10 is the portion the F detail drawing of the utility model Fig. 1.

Appended drawing reference:

1- valve body；11- straightway；12- introduction segment；121- chamfering；13- exports section；14- dowel；The first fillet of 141-； The second fillet of 142-；2- spool；21- valve rod；22- piston；The second O-ring of 221-；23- whale core moves head；231- sealing； 232- support portion；2311- First Transition arc section；2312- the first oblique line section；The second transition circle segmental arc of 2313-；2314- is horizontal Section；3- directed cavity；4- tail is stifled；The 4th O-ring of 41-；5- exhaust passage hole；51- seals silk plug；52- third O-ring；6- sealing Silk ring；The first O-ring of 61-；62- sealing ring；7- dielectric channel hole；71- water pipe；72- hydraulic conversion cylinder；73- oil cylinder；74- liquid Pressure station.

Specific embodiment

It should be noted that in the absence of conflict, the feature in the embodiments of the present invention and embodiment can To be combined with each other.

In the description of the present invention, it should be understood that term " center ", " longitudinal direction ", " transverse direction ", "upper", "lower", The orientation or positional relationship of the instructions such as "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outside" is It is based on the orientation or positional relationship shown in the drawings, is merely for convenience of describing the present invention and simplifying the description, rather than indicate Or imply that signified device or element must have a particular orientation, be constructed and operated in a specific orientation, therefore cannot understand For limitations of the present invention.In addition, term " first ", " second " etc. are used for description purposes only, and should not be understood as indicating Or it implies relative importance or implicitly indicates the quantity of indicated technical characteristic." first ", " second " etc. are defined as a result, Feature can explicitly or implicitly include one or more of the features.It is in the description of the present invention, unless another It is described, the meaning of " plurality " is two or more.

In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, term " is pacified Dress ", " connected ", " connection " shall be understood in a broad sense, for example, it may be being fixedly connected, may be a detachable connection, or integrally Connection；It can be mechanical connection, be also possible to be electrically connected；Can be directly connected, can also indirectly connected through an intermediary, It can be the connection inside two elements.For the ordinary skill in the art, on being understood by concrete condition State the concrete meaning of term in the present invention.

It elaborates with reference to the accompanying drawing to specific embodiment of the utility model.

As shown in FIG. 1 to FIG. 9, the utility model be hydraulic-driven axial flow valve, valve body 1 and spool 2 including coaxial arrangement, Valve body 1 includes inlet and outlet, and one end of close water outlet is equipped with directed cavity 3, directed cavity 3 and valve body 1 in valve body 1 It is fixedly installed between inner wall by dowel 14, directed cavity 3 is equipped with tail stifled 4, one end of spool 2 close to the sealing of one end of water outlet It is located in directed cavity 3 and the two is sealed is slidably connected, the other end and water inlet of spool 2 are equipped with beating for control water inlet It is open and close, inlet and outlet coaxial arrangement.

Preferably, valve body 1 includes intermediate straightway 11, the introduction segment 12 close to water inlet and the export close to water outlet The equal arc gradual change of the relatively straight line segment 11 of internal diameter of section 13, introduction segment 12 and export section 13 is gradually reduced and final output is linear Fixed diameter, introduction segment 12 far from water outlet one end be equipped with chamfering 121, have certain guide functions to medium；More preferably Ground, the internal diameter of introduction segment 12 are the 7/10 of 11 internal diameter of straightway, are guaranteed under valve opening state, and medium, which enters, quick reduction To the impact inside valve body 1, the intensity of poppet body 1, the wall thickness of introduction segment 12 is greater than the wall thickness of straightway 11, facilitates sealing The installation of silk ring 6, guarantees the intensity of 6 installation place of sealing filament ring, and the outer diameter of introduction segment 12 is equal to the internal diameter of export section 13, is conducive to The quick outflow of medium further reduced impact of the medium to valve body 1 and spool 2, the stabilization of lift structure to a certain extent Property, the wall thickness of export section 13 is less than or equal to the wall thickness of straightway 11, under the premise of not influencing intensity, saves material, reduces cost.

Preferably, introduction segment 12 is equipped with positioning convex platform close to one end of water inlet, and the inner cavity of introduction segment 12 is equipped with sealing Silk ring 6, one end and the positioning convex platform of sealing filament ring 6 are equipped with, and the other end extend into the inside of introduction segment 12 and valve cooperates Setting, the outer ring of sealing filament ring 6 match setting with the inner ring of introduction segment 12, and the first O is equipped between positioning convex platform and sealing filament ring 6 Type circle 61, sealing filament ring 6 are equipped with sealing ring 62 far from the inner ring of inlet port one end, are promoted close between spool 2 and sealing filament ring 6 Feng Xing.

Preferably, the length of directed cavity 3 is greater than the 1/2 of the length of straigh line of valve body 1, slightly larger than the 1/2 of 1 length of valve body, Guarantee that spool 2 and directed cavity 3 have enough lengths of fit, guarantee the stability that spool 2 acts, 3 outer ring of directed cavity from close into Mouth of a river one end to close to water outlet one end end face be gradually reduced and slope be 2.2~3.2 degree, preferably 2.7 degree, streamline knot Structure can effectively avoid the impact of medium, the stability of lift structure.

Preferably, as shown in Figure 7 and Figure 8, the quantity of dowel 14 is five and length is identical as the length of directed cavity 3, The axis that five dowels 14 are oppositely oriented chamber 3 is uniformly arranged, and the junction of dowel 14 and directed cavity 3 is equipped with the first fillet 141, dowel 14 and the inner wall junction of valve body 1 are equipped with the second fillet 142, the radius of the first fillet 141 and the second fillet 142 Radius it is identical, the first fillet 141 and the second fillet 142, which is arranged, can avoid stress concentration, promote the intensity of directed cavity 3.

Preferably, as shown in figs. 1,2 and 6, directed cavity 3 is equipped with the exhaust with external connection close to one end that tail blocks up 4 Access opening 5 and dielectric channel hole 7, exhaust passage hole 5 and dielectric channel hole 7 are each provided on dowel 14, and exhaust passage hole 5 passes through The sealing silk plug 51 of matching setting realizes opening and closing, seals and is equipped with the second O-ring 221 between silk plug 51 and valve body 1, guarantees sealing filament Leakproofness between stifled 51 and valve body 1, prevents medium from revealing, and dielectric channel hole 7 and driving spool 2 are with respect to the liquid that valve body 1 moves Driving assembly is pressed to be connected to, the axis of exhaust passage hole 5 and dielectric channel hole 7 is located in same level, facilitates and is processed, and drops Low processing cost.

Preferably, as shown in Fig. 2, hydraulic-driven component includes hydraulic conversion cylinder 72, hydraulic conversion cylinder 72 passes through water pipe 71 It is connected to dielectric channel hole 7, hydraulic conversion cylinder 72 realizes movement by the oil cylinder 73 that hydraulic station 74 drives, and water pipe 71 is that can hold By the copper pipe of negative pressure, this structure is simple, easy to maintain, reliable and stable.

Preferably, as shown in figure 9, spool 2 includes valve rod 21, valve rod 21 is equipped with whale core close to one end of water inlet and moves head 23, the other end is equipped with piston 22, and piston 22 is located in directed cavity 3 and the two is slidably connected, outer ring and the directed cavity 3 of piston 22 Multiple third O-rings 52 disposed in parallel are equipped between inner wall, as shown in figure 5, the quantity of third O-ring 52 is five and is evenly distributed with The outer ring of piston 22 is set, increases the leakproofness between piston 22 and directed cavity 3, is additionally provided on valve rod 21 flat with piston 22 The guide pad of row setting, guide pad are located at whale core and move between piston 22, and guide pad is located in directed cavity 3 and slides with directed cavity 3 Dynamic connection, plays certain guiding role, guarantees that the linear motion of piston 22 is more accurate, promotes whale core and moves head 23 and sealing filament The precision that ring 6 cooperates, it is highly preferred that valve rod 21 is hollow bar structure, the intensity of poppet stem 21, and the entire spool 2 of reduction Weight, and then reduce the power for the hydraulic-driven component that driving stem 21 moves, save it is more preferable so that structure is more stable.

Preferably, it is shell-like structure that whale core, which moves head 23, and whale core moves the sealing 231 and support portion that head 23 includes circular sliding slopes 232, the opening and closing of water inlet is realized in the inner wall cooperation of sealing 231 and valve body 1, support portion 232 be located at sealing 231 far from into The one end at the mouth of a river, support portion 232 are coaxially disposed with open circles taper and with valve rod 21, and support portion 232 is from water inlet to water outlet Section be gradually reduced and slope be 2.5~3.5 degree, the slope of support portion 232 is consistent with the slope of 3 outer ring of directed cavity, in valve Under the retracted mode of bar 21, support portion 232 is bonded setting with the section of directed cavity 3, in bonding position, the outer diameter of support portion 232 It is identical as the outer diameter of directed cavity 3；It is symmetrical arranged it is highly preferred that whale core moves the opposite valve rod 21 of head 23, it includes successively that whale core, which moves head 23, The First Transition arc section 2311 of connection, the first oblique line section 2312, the second transition arc and horizontal segment 2314, First Transition circular arc Section 2311 is located between the first oblique line section 2312 and support portion 232, and the second transition circle segmental arc 2313 is located at the first oblique line section 2312 Between horizontal segment 2314, horizontal segment 2314 is located at the top of valve rod 21 and is arranged in parallel with piston 22, First Transition arc section 2311 contact setting with sealing filament ring 6, using the structure on similar whale head, before can greatly reduce close to the part of water inlet Resistance to water-flow under closed state, reduces impact of the medium to spool 2, and under opening state, reducing has while impact to spool 2 Conducive to the quick separation of medium, the intensity and service life of spool 2 are promoted.

Preferably, as shown in Figure 10, tail stifled 4 protrudes setting for arch and to one end close to water outlet, tail stifled 4 with to leading To the 4th O-ring 41 is equipped between the end face of chamber 3, the leakproofness of tail stifled 4 with directed cavity 3, exhaust passage hole 5 and medium are promoted Access opening 7 blocks up 4 settings close to tail, when guarantee is filled with hydraulic medium for the first time, opens the exhaust silk plug above exhaust passage hole 5, row Air in net directed cavity 3, guarantees the movement travel of piston 22.

In practical work process, oil cylinder 73 is connected to hydraulic station 74, and hydraulic station 74 is that oil cylinder 73 provides medium, oil cylinder 73 It drives hydraulic conversion cylinder 72 to act, realizes the variation of medium in directed cavity 3, push piston 22 moves back and forth in directed cavity 3, real Existing whale core moves the closing and opening of 23 pairs of water inlets of head, and then realizes the movement that entire valve opens and closes, and is closing shape Under state, whale core moves head 23 and is equipped with sealing filament ring 6, it can be achieved that zero leakage, and spool 2 is shrunk to completely when valve wide open " whale core ", meticulously dynamic head is consistent with the outer ring slope of directed cavity 3 forms a streamline, and streamline is very good, similar to the structure of whale, Medium is discharged by being connected a plurality of cavities that muscle 14 separates by water outlet, inlet and outlet are coaxially set from water inlet It sets, and valve body 1 is full-bore, turbulent flow vibration will not be generated, when being filled with hydraulic medium for the first time, it is necessary to open exhaust passage hole Exhaust silk plug above 5 empties the air in directed cavity 3, guarantees the movement travel of piston 22, total spool 2 and valve body 1 It is arranged concentrically, substantially reduces vibration and noise caused by turbulent flow, 1 inner cavity of valve body is streamlined using leading directly to, and greatly reduces flowing resistance Power.

One embodiment of the utility model is described in detail above, but the content is only the utility model Preferred embodiment should not be considered as limiting the scope of the present invention.It is all to be made according to application scope of the utility model All the changes and improvements etc., should still belong within the patent covering scope of the utility model.

Claims (10)

1. hydraulic-driven axial flow valve, it is characterised in that: valve body and spool including coaxial arrangement, the valve body include water inlet and Water outlet is equipped with directed cavity close to one end of the water outlet in the valve body, the inner wall of the directed cavity and the valve body it Between be fixedly installed by dowel, the directed cavity is stifled equipped with tail close to the sealing of one end of the water outlet, the one of the spool End, which is located in the directed cavity, and the two is sealed is slidably connected, and the other end of the spool and the water inlet are equipped with control Make the opening and closing of the water inlet.

2. hydraulic-driven axial flow valve according to claim 1, it is characterised in that: the valve body include intermediate straightway, The internal diameter of introduction segment close to the water inlet and the export section close to the water outlet, the introduction segment and export section is with respect to institute State the equal arc gradual change of straightway be gradually reduced and final output be linear fixed diameter, the introduction segment is far from the water outlet One end of mouth is equipped with chamfering.

3. hydraulic-driven axial flow valve according to claim 2, it is characterised in that: the internal diameter of the introduction segment is the straight line The 7/10 of section internal diameter, the wall thickness of the introduction segment are greater than the wall thickness of the straightway, and the outer diameter of the introduction segment is equal to described lead The wall thickness of the internal diameter of section out, the export section is less than or equal to the wall thickness of the straightway.

4. hydraulic-driven axial flow valve according to claim 2, it is characterised in that: the introduction segment is close to one end of water inlet Equipped with positioning convex platform, the inner cavity of the introduction segment is equipped with sealing filament ring, one end of the sealing filament ring and the positioning convex platform Be equipped with, the other end extend into the inside of the introduction segment and the valve body is equipped with, the outer ring of the sealing filament ring with The inner ring of the introduction segment matches setting, and the first O-ring, the sealing are equipped between the positioning convex platform and the sealing filament ring Silk ring is equipped with sealing ring far from the inner ring of described inlet port one end.

5. hydraulic-driven axial flow valve according to claim 1, it is characterised in that: the length of the directed cavity is greater than the valve The 1/2 of the length of straigh line of body, the one end of the directed cavity outer ring from close to described water inlet one end to close to the water outlet End face is gradually reduced and slope is 2.2~3.2 degree.

6. hydraulic-driven axial flow valve according to claim 1, it is characterised in that: the quantity of the dowel is five and length Degree is identical as the length of the directed cavity, and the axis of the relatively described directed cavity of five dowels is uniformly arranged, the connection The junction of muscle and the directed cavity is equipped with the first fillet, and the inner wall junction of the dowel and the valve body is round equipped with second Angle, the radius of first fillet are identical as the radius of second fillet.

7. hydraulic-driven axial flow valve according to claim 1, it is characterised in that: the directed cavity close to the tail block up one End is equipped with exhaust passage hole and dielectric channel hole with external connection, and the exhaust passage hole and dielectric channel hole are each provided at described On dowel, the exhaust passage hole realizes opening and closing, the sealing silk plug and the valve body by the sealing silk plug of matching setting Between be equipped with the second O-ring, the hydraulic-driven component connection of the dielectric channel hole and the opposite valve body of driving spool.

8. hydraulic-driven axial flow valve according to claim 7, it is characterised in that: the hydraulic-driven component includes hydraulic rotation Cylinder is changed, the hydraulic conversion cylinder is connected to by water pipe with the dielectric channel hole, and the hydraulic conversion cylinder is driven by hydraulic station Oil cylinder realize movement.

9. hydraulic-driven axial flow valve according to claim 1, it is characterised in that: the spool includes valve rod, the valve rod Whale core is equipped with close to one end of the water inlet and moves head, and the other end is equipped with piston, and the piston is located in the directed cavity and two Person is slidably connected, and multiple third O-rings disposed in parallel, institute are equipped between the outer ring of the piston and the inner wall of the directed cavity State be additionally provided on valve rod with piston guide pad disposed in parallel, the guide pad be located at the whale core it is dynamic with the piston it Between, the guide pad is located in the directed cavity and is slidably connected with the directed cavity, and the valve rod is hollow bar structure.

10. hydraulic-driven axial flow valve according to claim 9, it is characterised in that: it is shell-like structure, institute that the whale core, which moves head, It states whale core and moves the sealing and support portion that head includes circular sliding slopes, the inner wall of the sealing and the valve body cooperates described in realization The opening and closing of water inlet, the support portion are located at the one end of the sealing far from the water inlet, the support portion and open circles It taper and is coaxially disposed with the valve rod, the support portion is gradually reduced and tiltedly from the water inlet to the section of the water outlet Rate is 2.5~3.5 degree, and under the retracted mode of the valve rod, the support portion is bonded setting with the section of the directed cavity, Bonding position, the outer diameter of the support portion are identical as the outer diameter of the directed cavity.