CN107796447A - A kind of orifice throttle structure - Google Patents

Abstract

The invention discloses a kind of orifice throttle structure, including two half shells, two half shells connect and compose housing by ring flange, sleeve pipe is installed on housing inner peripheral wall, secondary orifice plate is provided with the middle part of sleeve pipe, multiple primary orifice plates are evenly distributed on internal surface of sleeve pipe using secondary orifice plate as symmetry axis, and the both ends end of secondary orifice plate extends through the gap location extension between backward two ring flanges of sleeve pipe, and sealing gasket is provided with the extension two side of secondary orifice plate.The connecting end surface of secondary two half shells of orifice plate face, and two extensions of secondary orifice plate are respectively placed between two ring flanges, simultaneously sealing gasket is laid on the two side of extension, then two half shells are tightened together by bolt, so that two relative end faces of ring flange are directly pressed on sealing gasket, to complete to the sealing between sleeve pipe and housing.

Description

A kind of orifice throttle structure

Technical field

The present invention relates to flow sensor field, in particular to a kind of orifice throttle structure.

Background technology

When fluid flows through the throttling arrangement in pipeline, a fluid stream will form local contraction at the throttling element of throttling arrangement, So that flow velocity increases, static pressure is low, and pressure drop, i.e. pressure difference, the flow of media flow are then just generated before and after throttling element Bigger, caused pressure difference is bigger before and after throttling element, it is possible to weighs the size of fluid flow by measuring pressure difference.But It is that pressure at the vena contracta of the orifice plate in existing throttling arrangement is dropped to below the saturated vapour pressure under liquid corresponding temperature, Just there are steam and the gas being dissolved in water effusion in a fluid stream, form steam and the small bubble of gas mixing, pressure is lower, steam bubble It is more；When the pressure in orifice plate downstream is still below the saturated vapour pressure of liquid, the pipeline in downstream is continued to produce by steam bubble, liquid vapour Two-phase mixtures are present；If downstream pressure returns to the saturated vapour pressure higher than liquid, steam bubble is in the presence of high pressure, rapidly Condense and rupture, in the moment of steam bubble rupture, produce local hole, water under high pressure flows to these former steam bubbles with high speed to be occupied Space, formed an impulsive force；Because the gas in steam bubble and steam have little time, in moment all dissolving and condensations, impacting Power effect is lower to be divided into small bubble again, then is compressed, condenses by water under high pressure, is thusly-formed repeatedly repeatedly, orifice plate can be by more serious Cavitation influence, cause its service life to substantially reduce；And the replacing process of orifice plate is complex, substantial amounts of manpower thing is expended Power, add the use cost of throttling arrangement.

The content of the invention

It is an object of the invention to provide a kind of orifice throttle structure, avoids that cavitation phenomenons occurs on orifice plate, while Simplify the replacing flow of orifice plate when safeguarding, reduce the use cost of throttling arrangement.

The purpose of the present invention is achieved through the following technical solutions：

A kind of orifice throttle structure, including two half shells, ring flange, two half-shells are respectively arranged with the half shell end face Body connects and composes housing by ring flange, is provided with sleeve pipe on the housing inner peripheral wall, secondary is provided with the middle part of sleeve pipe Orifice plate, multiple primary orifice plates are evenly distributed on internal surface of sleeve pipe using secondary orifice plate as symmetry axis, the both ends end of the secondary orifice plate Portion extends through the gap location extension between backward two ring flanges of sleeve pipe, and on the extension two side of the secondary orifice plate It is provided with sealing gasket；Multiple perforates being arranged on the primary orifice plate include the first expansion being sequentially connected along a fluid stream direction of motion Big section, flat segments and the second expanding reach, first expanding reach, the internal diameter of the second expanding reach are passed along a fluid stream direction of motion Increase, and the axial length of first expanding reach is less than the axial length of the second expanding reach, is arranged on the secondary orifice plate The direction that hole diameter moves along a fluid stream is incremented by, and the internal diameter of aperture initial end is more than the internal diameter of the second expanding reach end.

In use, first the both ends of sleeve pipe are respectively placed in two half shells, until multiple primary orifice plates are evenly distributed on Inside two half shells, and the connecting end surface of secondary two half shells of orifice plate face, and two extensions of secondary orifice plate point It is not placed between two ring flanges, while sealing gasket is laid on the two side of extension, then by bolt by two half-shells Body tightens together so that two relative end faces of ring flange are directly pressed on sealing gasket, with complete to sleeve pipe and housing it Between sealing；After a fluid stream is entered by one end of half shell, now because two extensions of secondary orifice plate are fastened on ring flange On, i.e., whole sleeve pipe is fastened to enclosure interior, to ensure that sleeve pipe integrally keeps stable when being impacted by a fluid stream, and it is multiple Primary orifice plate and secondary orifice plate are provided with multiple round holes, and a fluid stream passes through the blocking of round hole, and its pressure declines, itself Energy start to be lost step by step, until a fluid stream is after one by one by primary orifice plate or secondary orifice plate, positioned at primary orifice plate or The pressure of secondary orifice plate is not less than the saturated vapour pressure of liquid, to reduce the generation of cavitation phenomenons, extends primary in sleeve pipe The service life of orifice plate and secondary orifice plate.And primary orifice plate, secondary orifice plate and sleeve pipe are overall structure, changed safeguarding When, only need to open ring flange then can take out the overall structure in the lump, rather than multiple orifice plates pass through multiple flanges in the prior art Fix and need repeated removal flange multiple in dismounting, and then reduce labor intensity of the orifice plate in installing/dismounting.

Wherein, the perforate on primary orifice plate includes three parts, i.e. the first expanding reach, flat segments and the second expanding reach, The internal diameter of first expanding reach and the second expanding reach is incremented by along the axial direction of perforate, and the internal diameter of flat segments then keeps constant, that is, is flowing When beam passes through the first expanding reach, its flow area constantly increases so that the flow velocity of fluid reduces, due to initial in the first expanding reach The pressure brought out is maximum, the fluid velocity flowed into by the initial end fluid speed that is maximum, and being moved along the first expanding reach inwall Spend it is relatively small, now then formed in the first expanding reach in the middle part of flow velocity is fast, surrounding flow velocity is slow transition flow regime, it is and relative with stream For the laminar condition of body, the transition flow regime of fluid to interfere between each water layer, consumes self-contained kinetic energy, i.e., gradually Reduce the pressure of fluid；After fluid flows into flat segments so that the motion state between each water layer is relatively steady, can avoid fluid Certain impact is being caused to primary orifice plate along flat segments axis direction generation component velocity, and is entering the second expanding reach in a fluid stream Afterwards, its running status is similar in the first expanding reach, and difference is that a fluid stream self-energy now is relatively weak, and second The axial length of expanding reach is more than the axial length of the first expanding reach, and then increases the attenuation rate of a fluid stream energy；Pass through perforate The decay step by step of interior three semiconvections speed energy, the impact strength that a fluid stream is formed when in direct-injection to next primary orifice plate are big It is big to reduce, that is, reduce the bearing load of primary orifice plate.Further, the hole diameter on secondary orifice plate is along a fluid stream direction of motion It is incremented by, i.e., a fluid stream will also carry out primary energy decay, and the initial end of aperture when through small holes, i.e., contacted at first with a fluid stream One end, the pressure value of the second expanding reach end of the relatively previous primary orifice plate of now suffered pressure value is small, and small The initial end internal diameter in hole is more than the internal diameter of the second expanding reach end, i.e., the pressure value of a fluid stream is maintained into the saturation not less than fluid Vapour pressure force value, guarantee will not be influenceed with the primary orifice plate contacted after a fluid stream by fluid cavitation.

Sealing ring is connected with two end faces of described sleeve pipe, and the sealing ring external diameter is more than the external diameter of described sleeve pipe. Because sleeve pipe is placed in inner walls, and minimum gap occurs between inner walls and sleeve pipe, and high-speed motion A fluid stream can be scurried into the gap, and multiply adverse current is formed in housing, influences the normal motion of a fluid stream, and sleeve pipe and housing Inwall washes away by fierce and causes stress raisers, that is, causes to damage；And the clamping on two end faces of sleeve pipe There is sealing ring, and the external diameter of the sealing ring is more than the external diameter of sleeve pipe, when sleeve pipe is put into half shell, sealing ring is with cannula tip Moved together on half shell inwall, while sealing ring is compressed and is tightly fitted on half shell inwall, to ensure sleeve pipe Sealing between outer wall and half shell inwall.

The axial width of the secondary orifice plate is more than the axial width of the primary orifice plate.A fluid stream passes through multiple primary successively Secondary orifice plate is flowed through after orifice plate, finally again through multiple primary orifice plates, and then the momentum for possessing a fluid stream itself runs out of Finish, and during a fluid stream moves, it is impaired relatively serious with several primary orifice plates that a fluid stream contacts at first, and when a fluid stream moves During to secondary orifice plate, the impact strength of the relatively large secondary orifice plate of axial width is greater than primary orifice plate, that is, can guarantee that set Pipe continues to use in housing.

The present invention compared with prior art, has the following advantages and advantages：

1st, primary orifice plate, secondary orifice plate and sleeve pipe of the invention are overall structure, when safeguarding replacing, only need to open ring flange The overall structure can then be taken out in the lump, rather than multiple orifice plates are fixed by multiple flanges and needed in dismounting in the prior art Repeated removal flange is multiple, and then reduces labor intensity of the orifice plate in installing/dismounting；

2nd, the present invention is connected with sealing ring on two end faces of sleeve pipe, and the external diameter of the sealing ring is more than the external diameter of sleeve pipe, When sleeve pipe is put into half shell, sealing ring is moved with cannula tip on half shell inwall, while sealing ring is compressed And be tightly fitted on half shell inwall, to ensure the sealing between sleeve outer wall and half shell inwall；

3rd, for the present invention when a fluid stream is moved to secondary orifice plate, the impact strength of the relatively large secondary orifice plate of axial width is big In primary orifice plate, that is, it can guarantee that sleeve pipe continues to use in housing.

Brief description of the drawings

Accompanying drawing described herein is used for providing further understanding the embodiment of the present invention, forms one of the application Point, do not form the restriction to the embodiment of the present invention.In the accompanying drawings：

Fig. 1 is schematic structural view of the invention；

Fig. 2 is the structural representation of perforate；

Fig. 3 is the structural representation of aperture.

Mark and corresponding parts title in accompanying drawing：

1- sealing rings, 2- sleeve pipes, 3- primary orifice plate, the expanding reach of 31- first, 32- flat segments, the expanding reach of 33- second, 4- secondary apertures Plate, 41- apertures, 5- half shells, 6- ring flanges, 7- sealing gaskets.

Embodiment

For the object, technical solutions and advantages of the present invention are more clearly understood, with reference to embodiment and accompanying drawing, to this Invention is described in further detail, and exemplary embodiment of the invention and its explanation are only used for explaining the present invention, do not make For limitation of the invention.

Embodiment 1

As shown in Fig. 1 ~ Fig. 3, the present embodiment includes two half shells 5, and ring flange 6 is respectively arranged with the end face of half shell 5, Two half shells 5 connect and compose housing by ring flange 6, sleeve pipe 2 are provided with the housing inner peripheral wall, in sleeve pipe 2 Portion is provided with secondary orifice plate 4, and multiple primary orifice plates 3 are that symmetry axis is evenly distributed on the inwall of sleeve pipe 2 with secondary orifice plate 4, described The both ends end of secondary orifice plate 4 extends through the gap location extension between 2 backward two ring flanges 6 of sleeve pipe, and in the secondary Sealing gasket 7 is provided with the extension two side of orifice plate 4；Multiple perforates being arranged on the primary orifice plate 3 are included along a fluid stream The first expanding reach 31 that the direction of motion is sequentially connected, the expanding reach 33 of flat segments 32 and second, first expanding reach 31, second The internal diameter of expanding reach 33 is incremented by along a fluid stream direction of motion, and the axial length of first expanding reach 31 is less than the second expanding reach 33 axial length, the direction that the internal diameter of aperture 41 being arranged on the secondary orifice plate 4 moves along a fluid stream are incremented by, and at the beginning of aperture 41 The internal diameter at top is more than the internal diameter of the end of the second expanding reach 33.

In use, first the both ends of sleeve pipe 2 are respectively placed in two half shells 5, until multiple primary orifice plates 3 are uniformly distributed Inside two half shells 5, and the connecting end surface of two half shells 5 of face of secondary orifice plate 4, and two of secondary orifice plate 4 prolong Stretch section to be respectively placed between two ring flanges 6, while sealing gasket 7 is laid on the two side of extension, then will by bolt Two half shells 5 are tightened together so that the relative end face of two ring flanges 6 is directly pressed on sealing gasket 7, to complete to set Sealing between pipe 2 and housing；After a fluid stream is entered by one end of half shell 5, now due to two extensions of secondary orifice plate 4 It is fastened on ring flange 6, i.e., whole sleeve pipe 2 is fastened to enclosure interior, to ensure that sleeve pipe 2 is overall when being impacted by a fluid stream Keep stable, and multiple primary orifice plates 3 and secondary orifice plate 4 are provided with multiple round holes, a fluid stream passes through the resistance of round hole Disconnected, its pressure declines, and the energy of itself starts to be lost step by step, until a fluid stream is passing through primary orifice plate 3 or secondary orifice plate 4 one by one Afterwards, the pressure at primary orifice plate 3 or secondary orifice plate 4 is not less than the saturated vapour pressure of liquid, to reduce cavitation phenomenons Generation, extend sleeve pipe 2 in primary orifice plate 3 and secondary orifice plate 4 service life.And primary orifice plate 3, secondary orifice plate 4 and Sleeve pipe 2 is overall structure, is safeguarding that only need to open ring flange 6 then can take out the overall structure in the lump, and non-existing when changing Multiple orifice plates are fixed by multiple flanges and need repeated removal flange multiple in dismounting in technology, and then reduce hole Labor intensity of the plate in installing/dismounting.

Wherein, the perforate on primary orifice plate 3 includes three parts, i.e. the first expanding reach 31, flat segments 32 and second expand Big section 33, the internal diameter of the first expanding reach 31 and the second expanding reach 33 is incremented by along the axial direction of perforate, and the internal diameter of flat segments 32 is then protected To hold constant, i.e., when a fluid stream passes through the first expanding reach 31, its flow area constantly increases so that the flow velocity of fluid reduces, due to Maximum in the pressure that the first expanding reach 31 is initially brought out, the fluid velocity flowed into by the initial end is maximum, and expands along first The fluid velocity of section 31 inwalls movement is relatively small, now then formed in the first expanding reach 31 in the middle part of flow velocity is fast, surrounding flow velocity Slow transition flow regime, and it is relative with for the laminar condition of fluid, the transition flow regime of fluid to interfere between each water layer, disappear Self-contained kinetic energy is consumed, i.e., gradually reduces the pressure of fluid；After fluid flows into flat segments 32 so that the fortune between each water layer Dynamic state is relatively steady, and fluid can be avoided to cause necessarily to rush to primary orifice plate along the axis direction of flat segments 32 generation component velocity Hit, and after a fluid stream enters the second expanding reach 33, its running status is similar in the first expanding reach 31, and difference is now A fluid stream self-energy is relatively weak, and the axial length of the second expanding reach 33 is more than the axial length of the first expanding reach 31, enters And increase the attenuation rate of a fluid stream energy；I.e. by the decay step by step of three semiconvection speed energy in perforate, a fluid stream in direct-injection extremely The impact strength formed when on next primary orifice plate 3 substantially reduces, that is, reduces the bearing load of primary orifice plate 3.Further Ground, the internal diameter of aperture 41 on secondary orifice plate 4 are incremented by along a fluid stream direction of motion, i.e., a fluid stream will also be carried out once when through small holes 41 Energy attenuation, and the initial end of aperture 41, i.e., the one end contacted at first with a fluid stream, now suffered pressure value are relatively previous The pressure value of the end of the second expanding reach 33 of individual primary orifice plate 3 is small, and the initial end internal diameter of aperture 41 is more than the second expanding reach The internal diameter of 33 ends, i.e., maintain the saturated vapor pressure force value not less than fluid by the pressure value of a fluid stream, and guarantee is followed by with a fluid stream Tactile primary orifice plate 3 will not be influenceed by fluid cavitation.

The present embodiment is connected with sealing ring 1 on 2 two end faces of described sleeve pipe, and the external diameter of the sealing ring 1 is more than described The external diameter of sleeve pipe 2.Because sleeve pipe 2 is placed in inner walls, and occur between inner walls and sleeve pipe 2 it is minimum between Gap, and a fluid stream of high-speed motion can be scurried into the gap, and multiply adverse current is formed in housing, influence the normal motion of a fluid stream, And sleeve pipe 2 and inner walls are washed away by fierce and cause stress raisers, that is, cause to damage；And in sleeve pipe Sealing ring 1 is connected with 2 two end faces, and the external diameter of the sealing ring 1 is more than the external diameter of sleeve pipe 2, and half shell is put into sleeve pipe 2 When in 5, sealing ring 1 is moved with the end of sleeve pipe 2 on the inwall of half shell 5, while sealing ring 1 is compressed and is tightly bonded On the inwall of half shell 5, to ensure the sealing between the outer wall of sleeve pipe 2 and the inwall of half shell 5.

Preferably, the axial width of the secondary orifice plate 4 is more than the axial width of the primary orifice plate 3.A fluid stream is successively Secondary orifice plate 4 is flowed through after multiple primary orifice plates 3, finally again through multiple primary orifice plates 3, and then has a fluid stream itself Standby momentum is exhausted, and during a fluid stream moves, it is impaired relatively tight with several primary orifice plates 3 that a fluid stream contacts at first Weight, and when a fluid stream is moved to secondary orifice plate 4, the impact strength of the relatively large secondary orifice plate 4 of axial width is greater than just Level orifice plate 3, that is, can guarantee that sleeve pipe 2 continues to use in housing.

Above-described embodiment, the purpose of the present invention, technical scheme and beneficial effect are carried out further Describe in detail, should be understood that the embodiment that the foregoing is only the present invention, be not intended to limit the present invention Protection domain, within the spirit and principles of the invention, any modification, equivalent substitution and improvements done etc., all should include Within protection scope of the present invention.

Claims (3)

1. a kind of orifice throttle structure, including two half shells（5）, in the half shell（5）End face is respectively arranged with ring flange （6）, two half shells（5）Pass through ring flange（6）Connect and compose housing, it is characterised in that：Pacify on the housing inner peripheral wall Equipped with sleeve pipe（2）, in sleeve pipe（2）Middle part is provided with secondary orifice plate（4）, multiple primary orifice plates（3）With secondary orifice plate（4）To be symmetrical Axle is evenly distributed on sleeve pipe（2）On inwall, the secondary orifice plate（4）Both ends end extend through sleeve pipe（2）Backward two methods Blue disk（6）Between gap location extension, and in the secondary orifice plate（4）Extension two side on be provided with sealing gasket（7）；It is more It is individual to be arranged on the primary orifice plate（3）On perforate include the first expanding reach for being sequentially connected along a fluid stream direction of motion（31）, it is flat Straight section（32）And second expanding reach（33）, first expanding reach（31）, the second expanding reach（33）Internal diameter transported along a fluid stream Dynamic direction is incremented by, and first expanding reach（31）Axial length be less than the second expanding reach（33）Axial length, be arranged on The secondary orifice plate（4）On aperture（41）The direction that internal diameter moves along a fluid stream is incremented by, and aperture（41）The internal diameter of initial end is big In the second expanding reach（33）The internal diameter of end.

A kind of 2. orifice throttle structure according to claim 1, it is characterised in that：In described sleeve pipe（2）On two end faces It is connected with sealing ring（1）, and the sealing ring（1）External diameter is more than described sleeve pipe（2）External diameter.

A kind of 3. orifice throttle structure according to claim 1, it is characterised in that：The secondary orifice plate（4）It is axially wide Degree is more than the primary orifice plate（3）Axial width.