CN204083378U - Close the low flow resistance axial flow type check valve of latter end band Slow Close protective function - Google Patents

Abstract

The utility model discloses a kind of low flow resistance axial flow type check valve of closing latter end band Slow Close protective function, its key problem in technology is: tail cone body is provided with tail cone water conservancy diversion group hole and passes into tail cone chamber, the front end of tail cone body is provided with tail cone restriction, damping lobe is installed on valve rod tail end, and its external diameter and tail cone restriction aperture are quite, periphery, front side is provided with the throttling conical surface; Be provided with cylindrical shape backward at flap bizet, flap cylindrical shell that cylindrical coordinates with valve body inner bag pilot hole; Through flow hole is provided with between the internal cavities of tail cone chamber and flap, valve body inner bag; Be provided with forward and backward guide sleeve in valve and carry out supporting guiding to valve rod, valve flowing channel is streamlined structure.Beneficial effect is: effective Slow Close can be provided to protect at valve closing latter end, Slow Close protection mechanism reliable operation, structure is simple, cost of production is low; Not easily produce damage without exposing pipeline, there is not external leakage hidden danger, valve working temperature is unrestricted, and valve has lower crushing and larger negotiability.

Description

Close the low flow resistance axial flow type check valve of latter end band Slow Close protective function

Technical field

The utility model relates to a kind of valve mechanism, is specifically related to a kind of structure of axial flow type check valve.

Background technique

In industries such as petrochemical industry, rock gas, chemical industry, electric power, urban water supply and sewerages, in order to prevent in the system and pipeline of conveying fluid because power failure or equipment failure cause reverse flow of fluids, make motor and pump reversing, and then the safe operation affecting pipeline and equipment even brings the badly damaged of pipe network and equipment, and delivery side of pump or pipeline need to arrange safety check.For the especially bigbore safety check of all kinds of safety check, if do not arrange Slow Close operator guards in valve mechanism design, when causing medium to flow backwards due to reasons such as terminations of pumping, under the spring-force driven dual of the spring set by the huge thrust of the medium of reverse flow and some valve internal, flap with acceleration or with ever-increasing fluctuating acceleration to closing direction rapid movement and closedown, except bringing the damage of intense impact and the vibration produced therefrom and strong noise and even sealing surface to sealing surface and valve, more seriously, because the flow velocity of fluid in pipeline is down to zero rapidly from maximum refluence speed, the kinetic transformation of fluid is static energy, the static pressure in pipeline can be made to raise rapidly, generation may have the water hammer of destruction to pipe-line system, serious destructive water hammer even can make pipeline and valve body produce explosion, consequence is comparatively serious.Therefore, the safety check that bore is larger should arrange Slow Close operator guards; The better set-up mode of Slow Close operator guards is that the closing motion of latter end to flap of only closing at flap arranges damping; when medium flows backwards; flap the leading portion of closing still can quick closedown with the safety of available protecting pump and system; and carry out slowing down, realizing Slow Close at closedown latter end, to alleviate or to eliminate impact and water hammer.

Existing safety check product adopts following three kinds of Slow Close operator guards usually: 1, arrange rocking arm and heavy hammer structure produces the moment contrary with flap closing direction to postpone the shut-in time (see Fig. 1 and Fig. 2) of flap in the roller end passing valve body.The shortcoming of this structure is: the effect of (1), Slow Close protection is poor, flap is assisted to maintain fully open position, the vibration eliminating flap and drift, to alleviate and to eliminate the wearing and tearing of rotating shaft and the impact noise of flap and valve body when the effect of weight is more and is embodied in valve opening; (2), the opposing torque of weight is attached to the whole process that flap is closed, and is unfavorable for the safety protection to pump and system; (3), the rotating shaft position that passes valve body generally can arrange filler compacting structure, and larger filler frictional force can hinder the motion of rotating shaft and flap, affects the operational safety of valve.2, adopt oil hydraulic cylinder oil pressure Slow Close, the set-up mode of oil cylinder is according to the difference of valve and Slow Close structural design, and some product damping functions are only arranged on flap and close latter end, and what have is then arranged on the whole process that flap closes.The shortcoming of this kind of slow-closing structure is: (1), structure are more complicated, and manufacture cost is high; (2), when refluence pressure is large or occur turbulent flow, cylinder piston motion is accelerated, and causes cushioning effect not obvious; (3), oil pipeline exposes, and easily breaks, and refuels also inconvenient; (4), the Sealing that uses in oil cylinder is rubber parts, and therefore the operating temperature of valve is restricted, and can only be used for normal temperature operating mode; (5), when oil cylinder is for arranging damping to flap whole process, the closing velocity of flap is comparatively slow, have impact on the performance of valve to the protective action of pump and system; (6), when oil cylinder arranges damping for closing latter end to flap, during valve closing, the piston rod end of flap fast approaching oil cylinder can produce stronger impact and impact sound; And the slippage of piston rod end and the valve flap contacts face surface of contact that the process of fastening likely can be hindered after damaging because of strong collision to certainly exist, this will cause piston rod jam and make flap be difficult to arrive closed positions.3, built-in Slow Close piston cylinder is set and using the operating mode medium in valve as the working medium of piston cylinder, as shown in Figure 3, Figure 4, its shortcoming is: (1), when in medium containing impurity time, impurity may make piston produce jam or cause piston or cylinder surface to occur pulling, thus can affect the reliability of damping mechanism work; (2), easily occur the phenomenon of impurity blocking bypass tube, after bypass tube is blocked, damping mechanism cannot play a role; (3), be the liquid easily freezed as what carry in pipeline, as working medium be water time, once the medium in bypass tube because of low temperature with do not flow and freeze, also can cause damping mechanism ineffective.

Above-mentioned Slow Close operator guards is mainly used in the butterfly-type safety check of Swing check valve, two bias or three eccentricity.For the safety check that some specific operation uses, safety check as supporting in petrochemical plant olefin hydrocarbon apparatus pipeline, because the working pressure of medium is lower, requires the safety check selecting low pressure drop; Some remote field long-distance transport pipes as on natural gas line the safety check installed, also require to reduce possible leak leak source and the outside demountable structure do not led to body cavity except requiring low pressure loss as far as possible.These specific product type selections require all to impel user to select the safety check-axial flow type check valve of another kind of type, are the comparatively typical structure of one of existing axial flow type check valve product as shown in Figure 5.Axial flow type check valve due to valve body be overall full-closed structure, the external leakage of medium can be blocked completely, and carried out the prerequisite of reasonable and sufficient optimal design at the runner of valve under, axial flow type check valve can obtain relative lower flow resistance coefficient and crushing, can obtain the negotiability larger than the safety check of other type.For the axial flow type check valve that axial flow type check valve especially bore is larger, equally also need to arrange Slow Close operator guards to alleviate or eliminate impact when flap is closed and water hammer; Structural feature due to axial flow type check valve is different from the safety check of other type, valve rod is positioned at closing or hemi-closure space in the middle of valve; this brings difficulty to the setting of Slow Close operator guards, and therefore existing axial flow type check valve temporarily also lacks the product being provided with Slow Close operator guards with use value and can be used for relevant applying working condition for type selecting and supporting.

Summary of the invention

In order to overcome the above-mentioned some shortcomings part existing for existing product, the utility model provides a kind of structure of low flow resistance axial flow type check valve of the closedown latter end band Slow Close protective function at valve, this structure can provide effective Slow Close to protect at the closedown latter end of valve thus valve effectively be alleviated while the safety of pump and system that can adequately protect or eliminates impact and water hammer, Slow Close operator guards reliable operation, structure is simple with manufacture, cost of production is low, not easily produce damage, there is not external leakage hidden danger, operating temperature is unrestricted; In addition valve has lower crushing and larger negotiability.

To achieve these goals, the utility model is by the following technical solutions:

A kind of low flow resistance axial flow type check valve of closing latter end band Slow Close protective function, its major part comprises valve body, flap, at valve body inlet side inwall and and the valve seat that is tightly connected between valve body, by the valve rod that screw thread and weld seam and flap connect as one, be installed on the damping lobe of valve rod tail end, be threaded connection the valve body inner bag tail end that is installed on valve body and the basic shape of outer surface is tip towards the tail cone body of the taper in valve outlet direction and the spring seat of valve body inner bag lumen and the spring that are fixedly installed in valve body, its basic technological scheme and major technique key are: the inside of tail cone body is cavity--tail cone chamber, tail cone body is provided with the tail cone water conservancy diversion group hole be made up of multiple through hole inside from its conical outer surface, tail cone body is provided with towards the front end in valve inlet direction circular tail cone restriction, when valve wide open, the damping lobe being installed on the revolution bodily form of valve rod tail end is positioned at tail cone chamber, the crown flap main body of flap front portion--flap bizet is provided with columnar flap cylindrical shell backward, the cylindrical of flap cylindrical shell is with the endoporus of valve body inner bag front end--inner bag pilot hole coordinates, through hole-the through flow hole between internal cavities between multiple connection flap bizet, flap cylindrical shell and valve body inner bag and tail cone body is also provided with at the step plane place of spring seat rear end.

In order to improve the performance with improving product, the utility model addition of following several further technological scheme:

The shape of the outer surface of the flap bizet of flap front portion is: middle part be to lordosis to valve body inlet side, the circular arc turning surface of surface for inwardly concaving, the recessed circular arc turning surface of circular arc turning surface laterally then for bulging, two sections of circular arc turning surface are tangent and form the streamline channel surface be smoothly connected.

The outside diameter of damping lobe is suitable with the aperture of tail cone restriction.

The periphery, front side of damping lobe is provided with the conical surface.

The housing of valve body is connected with uniform several gussets that are connected with between valve body inner bag, and the shape connecting gusset is the streamlined platy structure that two ends zoom in forward with arc surface.

Guide sleeve and rear guide sleeve before the endoporus place at spring seat two ends is arranged respectively, valve rod polished rod surface with front guide sleeve, rear guide sleeve endoporus assemble after for being slidably matched; Front guide sleeve and rear guide sleeve and valve rod surface-mounted before all carry out surface peening through thermo-chemical treatment.

In order to improve the manufacturability of product manufacturing, the utility model addition of following two further technological schemes:

It is the step hole that milling cutter is inwardly milled into from the conical surface that the section of opening is worked in the aperture, outside in tail cone water conservancy diversion group hole, and through hole is inwardly drill-through to tail cone chamber from step hole plane.

The flap shell portion of flap for be welded mutually with flap bizet with cylindrical component after roughing, and both weld, and rear one-tenth is as a whole forms flap through fine finishing.

In order to improve the operational safety of product, the utility model also addition of following two further technological schemes:

After front guide sleeve and rear guide sleeve load the installation step hole at spring seat two ends, load hole circlip in the annular groove that the aperture of the mounting hole often held processes, loads two circlip for holes in each annular groove.

Inside and outside concentric arrangement, dual spring that rotation direction is contrary is provided with in valve.

The beneficial effects of the utility model are: effective Slow Close can be provided to protect at the closedown latter end of valve, thus valve are effectively alleviated while the safety of pump and system that can adequately protect or eliminates impact and water hammer, avoid producing water flow impulsion; The structure of Slow Close protection mechanism is simple, only on the conventional structure not with Slow Close protection, add a damping lobe, thus product manufacturing is simple, cost of production is low, and the conversion of the product of band Slow Close operator guards and the conventional structure not with Slow Close protection when assembling is also comparatively simple, facilitates organization of production; Without exposing oil pipeline and medium bypass tube, not easily producing damage, without the need to refueling, and there is not blocking and the frozen problem of bypass tube yet; Without external structure, thus there is not external leakage hidden danger and there is not the problem that filler surface friction drag hinders flap motion; There is not the impact of flap and Slow Close mechanism and the jam of collision and part or pull, Slow Close operator guards reliable operation; Because Slow Close operator guards is embedding structure, without non-metallic seal, thus the operating temperature of valve can not be restricted; Specific aim, the better Slow Close protection mechanism of suitability can be selected and be built with to valve easily according to the different conditions of medium.In addition, compared with the safety check of other type, the valve of this structure has lower crushing and larger negotiability.

Accompanying drawing explanation

Fig. 1 is that existing safety check product arranges rocking arm and heavy hammer structure to postpone the product schematic diagram of the shut-in time of flap.

Fig. 2 is the left view of Fig. 1.

Fig. 3 is the product schematic diagram that existing safety check product arranges the Slow Close piston cylinder structure using operating mode medium as piston cylinder working medium.

Fig. 4 is the left view of Fig. 3.

Fig. 5 is the structural representation of the axial flow type check valve product of prior art.

Fig. 6 is the schematic diagram of the utility model embodiment.

Fig. 7 is the utility model embodiment one--damping valve structure schematic diagram when medium is liquid.

Fig. 8 is the utility model embodiment two--damping valve structure schematic diagram when medium is gas.

Fig. 9 is the left view of Fig. 7, Fig. 8.

Figure 10 is the utility model embodiment one--when medium is liquid, valve starts the schematic diagram entering the Slow Close stage.

Figure 11 is the utility model embodiment one--when medium is liquid, flap enters the schematic diagram in last decelerating phase.

Figure 12 is the utility model embodiment one--schematic diagram when valve enters closed condition when medium is liquid.

Figure 13 is the utility model embodiment two--when medium is gas, valve starts the schematic diagram entering the Slow Close stage

Figure 14 is the utility model embodiment two--when medium is gas, flap enters the schematic diagram in last decelerating phase.

Figure 15 is the utility model embodiment two--schematic diagram when valve enters closed condition when medium is gas.

Figure 16 is that product of the present utility model cancels damping lobe, as the schematic diagram during conventional products assembling do not protected with Slow Close.

In figure, 1, valve body; 1-1, connection gusset; 1-2, valve body inner bag; 1-3, inner bag pilot hole; 1-4, inner bag front-end face; 2, valve seat; 2-1, sealing surface of seat; 3, flap; 3-1, flap bizet; 3-2, valve clack sealing surface; 3-3, flap cylindrical shell; 4, valve rod; 5, tail cone body; 5-1, tail cone restriction; 5-2, tail cone chamber; 5-3, tail cone water conservancy diversion group hole; 6, damping lobe; 6-1, damping lobe inner cone; 6-2, damping lobe cylindrical; 7, nut; 8, spring pad; 9, cotter pin; 10, front guide sleeve; 11, spring; 12, spring seat; 13, through flow hole; 14, spring overcoat; 15, bolt; 16, rear guide sleeve; 17, circlip for hole.

Embodiment

Below in conjunction with accompanying drawing and two embodiments, the technical solution of the utility model is further elaborated.

Embodiment one

Axial flow type check valve described in the present embodiment is mainly used in the pipeline of liquid medium, automatic blocking-up valve when flowing backwards as preventing medium.

Be the basic structure schematic diagram of the low flow resistance axial flow type check valve technological scheme of the closedown latter end band Slow Close protective function that the utility model proposes as shown in Figure 6, its major part comprises: valve body (1), valve seat (2), flap (3), valve rod (4), tail cone body (5), damping lobe (6), spring (11), spring seat (12) and front guide sleeve (10) and rear guide sleeve (16).Valve seat (2) can in different ways according to the difference of valve aperture size in the means of fixation of valve body (1) inlet side inwall: in small-bore valve, valve seat (2) can be fixed on valve body (1) with threaded engagement, seal with O type circle, large bore valves valve seat then should not adopt with the connection of valve body the mode be threaded, and need with the pattern of valve component and arrange certain mechanical connecting structure to fix valve seat, in the present embodiment, have employed three open loops loaded in valve body annular groove and fix valve seat (2), also sealing is ensured with O type circle, the surface of valve seat or valve component is that the conical surface of arc surface and both sides is smoothly connected, the conical surface of both sides is then substantially identical with the bearing of trend of valve body adjacently situated surfaces after the extension of both sides, makes valve seat or valve component and the valve body surface coherent streamline channel surface forming smoothness mutually, in valve body, the surface at other runner position also adopts smooth fairing ace.Be threaded connection between valve rod (4) and flap (3) after screwing, with argon-arc welding seam, both connected as one.Tail cone body (5) is threaded connection the tail end of the valve body inner bag (1-2) being installed on valve body (1), and the basic shape of tail cone body (5) outer surface is the taper of tip towards valve body (1) Way out.

Spring seat (12) is fixedly installed in valve body inner bag (1-2) middle part of valve body (1) by bolt (15), as supporting and the guiding element of spring (11), simultaneously also as supporting and the guiding element of flap (3) and valve rod (4) assemblying body.Due to the heavier-weight of flap (3) and valve rod (4) assemblying body, make easily to produce between the guide surface of valve rod (4) and spring seat (12) to pull, especially the axial flow type check valve that bore is larger is all the more so, therefore front guide sleeve (10) and rear guide sleeve (16) is provided with respectively at the endoporus place at spring seat (12) two ends, polished rod surface and the front guide sleeve (10) of valve rod (4), for being slidably matched after the endoporus assembling of rear guide sleeve (16), simultaneously, front guide sleeve (10) and rear guide sleeve (16) and valve rod (4) surface-mounted before all carry out in surface peening-the present embodiment through thermo-chemical treatment, front guide sleeve (10), ionic nitrizing treatment is all carried out in the surface of rear guide sleeve (16) and valve rod (4), the tension that can significantly improve the surface that is slidably matched hinders ability.After front guide sleeve (10) and rear guide sleeve (16) load the installation step hole at spring seat (12) two ends, load hole circlip (17) in the annular groove that the aperture of the mounting hole often held processes, loads two circlip for holes (17) in each annular groove; Circlip is adopted to prevent guide sleeve from deviating from, disassemble or assemble are quick, facilitate assembling and the maintenance of product, two circlips are loaded in annular groove simultaneously outside each guide sleeve, can reliability be improved, effectively avoid guide sleeve to be taken away the installation step hole at spring seat (12) two ends under the drive of the valve rod (4) of movement.

For the consideration of spring rate characteristic and the needs of raising reliability, the spring (11) of the present embodiment adopts two springs differing in size contrary with rotation direction to be installed in parallel, concentric arrangement inside and outside two springs.The setting of dual spring is adopted first to be consider: the spring force of a spring is split as and allows two springs jointly share, then the cross section of each spring is much less than the cross section of original spring, thus in identical length, spring can be arranged the more number of turns thus enable the stiffness characteristics of spring meet the needs of valve working better; In addition it is also apparent for adopting dual spring to be conducive to improving reliability: because spring material is through hardening process, when the unexpected impact of bearing valve opening and closing, be difficult to the unexpected situation definitely avoiding occurring spring breakage, therefore arrange dual spring help ensure valve use more reliably.The benefit that two spring rotation directions are contrary is: spring, when compressing and stretch, certain torsion can occur, thus likely can be driven by the end face of spring in the process of opening fast or closing when flap (3) and rotate, this can increase valve rod, guide sleeve surface and flap and wearing and tearing and abrasive possibility occur sealing surface of seat.After being provided with dual spring in valve, need the supporting and the guiding element that are used as outside spring at the arranged outside spring overcoat (14) of outside spring, and nationality helps bolt (15) to compress and fixing spring overcoat (14) and spring seat (12) simultaneously.The setting of dual spring is mainly used in bigbore axial flow type check valve, and smaller diameter valve still adopts single spring structure due to the restriction in space in valve, and now spring outwards does not just need to arrange spring overcoat (14).

As shown in Figure 7, the inside of tail cone body (5) is cavity--tail cone chamber (5-2), tail cone body (5) is provided with tail cone water conservancy diversion group hole (5-3) (see Fig. 9) of being made up of multiple through hole inside from the conical outer surface of tail cone body (5), for the ease of processing, each aperture, outside in tail cone water conservancy diversion group hole (5-3) is worked the section of opening milling cutter and is inwardly milled into formation step hole from the conical surface, and through hole is inwardly drill-through to tail cone chamber (5-2) from step hole plane; Towards the front end in valve inlet direction on tail cone body (5), and be provided with circular tail cone restriction (5-1); At the tail end of valve rod (4), the damping lobe (6) of the revolution bodily form is installed, damping lobe (6) is fixed with nut (7) and spring pad (8), and nut (7) is locking by cotter pin (9); When valve wide open, the damping lobe (6) being installed on valve rod (4) tail end is positioned at tail cone chamber (5-2); The diameter of damping lobe cylindrical (6-2) is suitable with the aperture of tail cone restriction (5-1), and the periphery, front side of damping lobe (6) is with the conical surface--damping lobe inner cone (6-1).In the present embodiment, damping lobe inner cone (6-1) is the narrower conical surface.

Valve flap structure aspect, from flap (3) anterior crown main body--flap bizet (3-1) backward, is provided with columnar flap cylindrical shell (3-3) (see Fig. 6), in the present embodiment, flap cylindrical shell (3-3) part is for be welded mutually after roughing with cylindrical component and flap bizet (3-1), become as a whole after both welding and form flap (3) through fine finishing, the external diameter of flap cylindrical shell (3-3) is less than the maximum outside diameter of flap bizet (3-1), is provided with a plane as spacing plane during flap (3) standard-sized sheet between the maximum outside diameter place of flap bizet (3-1) and flap cylindrical shell (3-3) cylindrical, cylindrical and valve body inner bag (1-2) front end of flap cylindrical shell (3-3) part endoporus--inner bag pilot hole (1-3) coordinates, when flap (3) arrives fully open position, aforesaid flap bizet (3-1) is with the front plan of the spacing plane between flap cylindrical shell (3-3) cylindrical with valve body inner bag (1-2)--inner bag front-end face (1-4) contacts, the fully open position of flap (3) is determined, flap bizet (3-1) outer surface links up mutually with valve body inner bag (1-2) outer surface simultaneously, smooth water-drop-shaped and fairshaped surface is connected to form with the outer surface of tail cone body (5) three.

Through hole-the through flow hole (13) between internal cavities between multiple connection flap bizet (3-1), flap cylindrical shell (3-3) and valve body inner bag (1-2) and tail cone body (5) is also provided with at the step plane place of spring seat (12) rear end., need to process the through flow hole (13) consistent with spring seat (12) in the corresponding position of the step plane of spring overcoat (14) after being provided with spring overcoat (14) when the structure that have employed dual spring.

When medium flows backwards, medium enters tail cone chamber (5-2) from the tail cone water conservancy diversion group hole (5-3) tail cone body (5), then enters into the internal cavities between flap bizet (3-1) and flap cylindrical shell (3-3) and valve body inner bag (1-2) by tail cone restriction (5-1) and through flow hole (13); Because the medium of the internal cavities entering into flap (3) does not have flow velocity substantially, medium static pressure is gone up completely, and the medium in flap (3) outside is the medium flow backwards at a high speed, the medium static pressure of a part has been converted into the kinetic energy of medium, thus the medium static pressure in flap (3) outside will lower than the medium static pressure of flap (3) inside, the spring force that pressure difference adds spring (11) can promote flap (3) and move to valve seat (2) direction, and flap (3) is closed.

As shown in Figure 10, when flap (3) returns and closes, when damping lobe (6) moves forward to comparatively close to tail cone restriction (5-1) place, damped lobe inner cone (6-1) and tail cone restriction (5-1) throttling from the medium that tail cone chamber (5-2) will enter into the internal cavities of flap (3), the rate-of flow flowed into reduces gradually, due to flap (3) move forward under inside and outside pressure medium difference and spring-force driven dual time, the volume of the internal cavities of flap (3) and valve body inner bag (1-2) is thereupon extended, when entering the medium of this internal cavities because being reduced by throttle-flow, when can not supplement the extended volume of this internal cavities in time on demand, because liquid medium can be considered to incompressible fluid, thus the medium static pressure of the internal cavities of flap (3) and valve body inner bag (1-2) can decline quickly, the speed of advancement of flap (3) also can comparatively fast decline, in the present embodiment, the stage of damping lobe (6) beginning throttling is set to remainder stroke accounts for total travel about 20%.Along with the continuation of flap (3) moves forward, when damping lobe cylindrical (6-2) starts to enter tail cone restriction (5-1) (see Figure 11), the passage that medium enters the internal cavities of flap (3) and valve body inner bag (1-2) is blocked completely--the stage that in the present embodiment, damping lobe cylindrical (6-2) enters tail cone restriction (5-1) be set to that remainder stroke accounts for total travel about 3 ~ 5%, because medium is incompressible liquid medium, if now passage is blocked completely, do not have medium can enter this internal cavities completely, then flap (3) can stop moving forward at once, because all there is matching gap between damping lobe cylindrical (6-2) and tail cone restriction (5-1) and between flap cylindrical shell (3-3) cylindrical and inner bag pilot hole (1-3), still have a certain amount of medium from this two gap location after damping lobe cylindrical (6-2) enters tail cone restriction (5-1) to continue to enter, and flap (3) has dropped to close to barometric pressure or the back pressure that drops to close to system returning seat to the pressure close to flap during closed position (3) outside (outflow side of refluence medium), thus when having a small amount of refluence medium to continue the internal cavities entering flap (3) and valve body inner bag (1-2) from above-mentioned two gap locations, flap (3) still can continue reach until close (Figure 12) with slower speed.Under the prerequisite correctly arranging the matching gap between damping lobe cylindrical (6-2) and tail cone restriction (5-1) and between flap cylindrical shell (3-3) cylindrical and inner bag pilot hole (1-3), flap (3) can arrive sealing surface of seat (2-1) place with required rational Slow Close speed in the final stage of closing; The remarkable reduction of speed that flap (3) is entering into reduction of speed gradually and closedown latter end 3 ~ 5% stroke of closing latter end 20% stroke can eliminate water hammer and protection sealing surface and valve very effectively from impact failure.

Above-mentioned flap closing process embodies the Slow Close operator guards that the utility model proposes and has mutative damp characteristic.Need here it is noted that the utility model have close total travel at flap and can meet the mutative damp characteristic that different phase control speed requires, be not available for the various Slow Close operator guards that adopt of current all kinds of safety check product.

Safety check product is full-gear when putting into operation, thus the pressure loss of large young pathbreaker to system of the resistance coefficient of its runner has a direct impact, therefore, during safety check product specification, to ensure while product performance should reduce the resistance coefficient of runner by rational design, this is that current all kinds of safety check product is generally out in the cold or fail to cause a problem of enough attention when designing as far as possible.The technical solution of the utility model, in order to reduce the resistance coefficient of valve, has carried out some new designs in the relevant surfaces of runner:

The profile design of the outer surface of the flap bizet (3-1) that flap (3) is anterior is: middle part be to lordosis to valve body (1) inlet side, the surperficial circular arc turning surface for inwardly concaving, recessed circular arc turning surface be then outwardly circular arc turning surface laterally, and two sections of circular arc turning surface are tangent and to form the streamline channel be smoothly connected surperficial.Valve clack sealing surface (3-2) be arranged on outwardly circular arc turning surface close to outside, slightly protrude from the surface of this circular arc turning surface.

The housing of valve body (1) be connected gusset (1-1) with uniform four between valve body inner bag (1-2) and be connected, the shape connecting gusset (1-1) is the streamlined platy structure (as shown in Figure 6) that two ends zoom in forward with arc surface.The connection gusset two ends of existing axial flow type check valve product adopt flush end or semi-circular ends, and MEDIA FLOW can produce vortex when this place; The connection gusset two ends of the technical program be zoom in forward with arc surface, two end part close to pointed streamlined structure, MEDIA FLOW can not produce when these two ends eddy current, can olderly flowage, be conducive to the flow resistance reducing runner.

The surface of the airflow design that above-mentioned flap bizet (3-1) is surperficial with being connected gusset (1-1) and aforesaid valve seat or valve component, valve body adjacently situated surfaces adopt the surface at other runner position in fairing ace coherent mutually and valve body to adopt the fairing ace of smoothness, define reasonable, the smooth streamline channel of valve, there is no the unexpected change of flow direction during media flow, there is no the flip-flop of cross section of fluid channel area, thus make valve have lower crushing and the flow coefficient of Geng Gao.

Embodiment two

From the structure of embodiment one the medium that is suitable for different, the axial flow type check valve described in the present embodiment is mainly used in the pipeline of gas medium, flows backwards for preventing medium.

Because gas medium is completely different from the characteristic of liquid medium; liquid medium is incompressible fluid; and gas medium is compressible fluid; thus the Slow Close operator guards being applied to this two classes medium is also different; for gas medium Slow Close operator guards because medium be that thus compressible fluid has hysteresis quality and low-response to the change of orifice size, need the characteristic for gas medium to design targetedly Slow Close operator guards.

The technological scheme of the present embodiment and the difference of embodiment one are only to have employed the different damping lobe (6) of structure, all the other structures are identical, stating for not doing below the technological scheme of these same structures to apply, only the Slow Close mechanism section relating to damping lobe (6) being illustrated.

As shown in Figure 8, the inside being installed on the tail cone body (5) of valve body inner bag (1-2) rear end is set to cavity-tail cone chamber (5-2), the conical surface of tail cone body (5) is provided with group hole-tail cone water conservancy diversion group hole (5-3) (Fig. 9) flowing into tail cone chamber (5-2) for medium, be provided with in the front end of tail cone body (5) circular, for medium from tail cone chamber (5-2) flow out and at Slow Close time carry out the tail cone restriction (5-1) of throttling; Be provided with the damping lobe (6) of the revolution bodily form at the tail end of valve rod (4), damping lobe (6) compresses with nut (7) and fixing, locking by cotter pin (9); During valve wide open, damping lobe (6) is positioned at the position that tail cone chamber (5-2) bores end side partially, the diameter of damping lobe cylindrical (6-2) and the aperture of tail cone restriction (5-1) are suitable, and the axial length of damping lobe cylindrical (6-2) is longer than length during liquid medium in embodiment one; In the periphery, front side of damping lobe (6) with the conical surface--damping lobe inner cone (6-1), in the present embodiment, damping lobe inner cone (6-1) is the longer conical surface of axial length, for during Slow Close to gas medium throttling.When medium flows backwards, certain media enters tail cone chamber (5-2) from tail cone water conservancy diversion group hole (5-3) and then enters into the internal cavities between flap bizet (3-1) and flap cylindrical shell (3-3) and valve body inner bag (1-2) by tail cone restriction (5-1) and through flow hole (13), because the medium entering into this internal cavities does not have flow velocity substantially, static pressure is gone up, and the medium in flap (3) outside is the medium flow backwards at a high speed, thus the medium static pressure in flap (3) outside will lower than the medium static pressure of flap (3) inside, the spring force that pressure difference adds upper spring (11) can promote flap (3) and move to valve seat (2) direction and flap (3) is closed.

As shown in figure 13, promote flap (3) when gas medium flows backwards and go back to pass, when the front end of the throttling conical surface-damping lobe inner cone (6-1) of damping lobe (6) front side moves forward to comparatively close to tail cone restriction (5-1) place, damped lobe inner cone (6-1) and tail cone restriction (5-1) throttling from the medium that tail cone restriction (5-1) flows out, rate-of flow reduces gradually, due to flap (3) move forward time, the volume of the internal cavities of flap (3) and valve body inner bag (1-2) is thereupon extended, when entering the medium of this internal cavities because being reduced by throttle-flow, then the medium static pressure of the internal cavities of flap (3) and valve body inner bag (1-2) can decline gradually, the speed of advancement of flap (3) also can decline to some extent.In the present embodiment, the stage of damping lobe (6) beginning throttling is set to remainder stroke accounts for total travel about 35 ~ 40%.Along with the continuation of flap (3) moves forward, damping lobe cylindrical (6-2) starts to enter tail cone restriction (5-1) (see Figure 14), the passage that medium enters the internal cavities of flap (3) and valve body inner bag (1-2) is blocked completely--the stage that in the present embodiment, damping lobe cylindrical (6-2) enters tail cone restriction (5-1) be set to that remainder stroke accounts for total travel about 10 ~ 15%, because flap (3) has dropped to close to minimum at time seat to the pressure close to flap during closed position (3) outside (outflow side of refluence medium), thus flap (3) still can continue reach with certain speed, the medium being enclosed in the internal cavities of flap (3) and valve body inner bag (1-2) is therefore made the pressure drop in cavity by dilatation gradually, flap (3) is slowed down until close (Figure 15).The setting of above-mentioned Slow Close protection can protect sealing surface and valve from impact failure effectively.

Embodiment two is different for the structure of the only damping lobe (6) of the Slow Close operator guards for liquid medium of the Slow Close operator guards of gas medium and embodiment one; and two kinds of damping lobes (6) are also identical with size with the linkage structure of valve rod (4), thus also organization of production can facilitated according to the different conditions of medium while selecting and be built with specific aim, the better Slow Close operator guards of suitability.

The Slow Close operator guards that the technical solution of the utility model proposes has the simple advantage of structure, and this structure only adds a part-damping lobe than the conventional structure not with Slow Close protection in number of spare parts, and thus product manufacturing is simple, cost of production is low.When the product that user purchases does not have Slow Close protection to require; the conversion of product when assembling with Slow Close operator guards and the conventional structure not with Slow Close protection is also comparatively simple; as long as do not fill damping lobe in valve stem end, the tail cone restriction position of tail cone body front end removed rear assembling by pattern requirement by turning simultaneously; just constitute and meet not with the product that the conventional structure product design document of Slow Close protection requires, as shown in Figure 16.

Because Slow Close operator guards of the present utility model is arranged in valve cavity, and the working medium of Slow Close protection mechanism is operating mode medium, thus valve is without exposing oil pipeline and medium bypass tube, product is not easy to produce and damages in installing and using, without the need to refueling, and there is not blocking and the frozen problem of bypass tube yet yet; Due on valve without external structure, thus there is not external leakage hidden danger and do not exist filler surface friction drag hinder flap motion problem; Because Slow Close protection of the present utility model is not structurally close to the piston rod clashing into and promote slow-closing structure during closed position by flap, therefore there is not the impact of flap and Slow Close mechanism and the jam of collision and part or pull, the work of Slow Close operator guards is more reliable; Because Slow Close operator guards is embedding structure; without nonmetallic Sealing; thus the operating temperature of valve can not be restricted, and only needs to select corresponding part material according to other characteristic of operating temperature and medium, valve just can be made to work under required any operating temperature.

Below in conjunction with the accompanying drawings and embodiments specific description has been done to the technical solution of the utility model, but these accompanying drawings and explanation can not be understood to limit scope of the present utility model.Those skilled in the art should know; the utility model is not subject to the restriction of above-described embodiment and accompanying drawing; its protection domain defined by appending claims; any in the technological scheme not exceeding the various changes in the scope that the utility model claims define, modification is formed; all do not depart from spirit of the present utility model and technical spirit, still can belong within right of the present utility model.

Claims (10)

1. close the low flow resistance axial flow type check valve of latter end band Slow Close protective function for one kind, it comprises valve body (1), flap (3), be positioned at valve body (1) inlet side inwall and the valve seat (2) be tightly connected with valve body (1), by the valve rod (4) that screw thread and weld seam and flap (3) connect as one, be installed on the damping lobe (6) of valve rod (4) tail end, be threaded connection valve body inner bag (1-2) tail end that is installed on valve body (1) and the basic shape of outer surface is the tail cone body (5) of tip towards the taper of valve body (1) Way out, be fixedly installed in spring seat (12) and the spring (11) of valve body inner bag (1-2) lumen of valve body (1), it is characterized in that: the inside of tail cone body (5) is cavity--tail cone chamber (5-2), tail cone body (5) is provided with the tail cone water conservancy diversion group hole (5-3) be made up of multiple through hole inside from its conical outer surface, tail cone body (5) is provided with towards the front end in valve inlet direction circular tail cone restriction (5-1), when valve wide open, the damping lobe (6) being installed on the revolution bodily form of valve rod (4) tail end is positioned at tail cone chamber (5-2), flap (3) anterior crown flap main body--flap bizet (3-1) is provided with columnar flap cylindrical shell (3-3) backward, the cylindrical of flap cylindrical shell (3-3) is with the endoporus of valve body inner bag (1-2) front end--inner bag pilot hole (1-3) coordinates, through hole-the through flow hole (13) between internal cavities between multiple connection flap bizet (3-1), flap cylindrical shell (3-3) and valve body inner bag (1-2) and tail cone body (5) is also provided with at the step plane place of spring seat (12) rear end.

2. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1; it is characterized in that: the shape of the outer surface of the flap bizet (3-1) that described flap (3) is anterior is: middle part be to lordosis to valve body (1) inlet side, the surperficial circular arc turning surface for inwardly concaving; the recessed circular arc turning surface of circular arc turning surface laterally then for bulging, two sections of circular arc turning surface are tangent and form the streamline channel surface be smoothly connected.

3. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1, is characterized in that: the outside diameter of described damping lobe (6) is suitable with the aperture of tail cone restriction (5-1).

4. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1, is characterized in that: the periphery, front side of described damping lobe (6) is with the conical surface.

5. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1; it is characterized in that: the housing of valve body (1) is connected with uniform several gussets (1-1) that are connected with between valve body inner bag (1-2), the shape connecting gusset (1-1) is the streamlined platy structure that two ends zoom in forward with arc surface.

6. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1; it is characterized in that: it is the step hole that milling cutter is inwardly milled into from the conical surface that the section of opening is worked in the aperture, outside in described tail cone water conservancy diversion group hole (5-3), through hole is inwardly drill-through to tail cone chamber (5-2) from step hole plane.

7. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1, it is characterized in that: be respectively arranged with front guide sleeve (10) and rear guide sleeve (16) at the endoporus place at described spring seat (12) two ends, for being slidably matched after the polished rod of valve rod (4) surface and the endoporus of front guide sleeve (10), rear guide sleeve (16) assemble; Front guide sleeve (10) and rear guide sleeve (16) and valve rod (4) surface-mounted before all carry out surface peening through thermo-chemical treatment.

8. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1; it is characterized in that: after front guide sleeve (10) and rear guide sleeve (16) load the installation step hole at spring seat (12) two ends; load hole circlip (17) in the annular groove that the aperture of the mounting hole often held processes, loads two circlip for holes (17) in each annular groove.

9. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1; it is characterized in that: flap cylindrical shell (3-3) part of described flap (3) is for be welded mutually after roughing with cylindrical component and flap bizet (3-1), and both weld, and rear one-tenth is as a whole forms flap (3) through fine finishing.

10. the low flow resistance axial flow type check valve of closedown latter end band Slow Close protective function according to claim 1, is characterized in that: be provided with inside and outside concentric arrangement, dual spring that rotation direction is contrary in valve.