A kind of little ball valve of reliable open and close torque that seals
Technical field
The utility model relates to a kind of valve, and more particularly, it relates to a kind of little ball valve of reliable open and close torque that seals.
Background technique
Pneumatic ball valve is very widely valve of a kind of use, its structure generally include the valve body with valve pocket, the spheroid that places valve pocket inside, and the valve rod that is connected of spheroid and place valve body and spheroid between valve seat, described valve stem part is placed on the valve body outside, the valve body outside is provided with the operation drive unit of actuate valve stem rotation, and 90 ° of rotations that operation drive unit actuate valve stem drives spheroid make ball valve reach the switching of opening and closing.The valve base sealing structure of tradition fixing ball valve and force analysis are as shown in Figure 1,1A is spheroid among Fig. 1,2A is valve seat insert, 3A is valve seat, 4A is spring, 5A is valve body, and 6A is the sealing between valve body and the valve seat, and the sealing between spheroid and the valve seat insert normally relies on the pretightening force of spring and acts on making a concerted effort of valve seat these two power of medium power behind.Usually the pretightening force of spring only is in order to ensure the fitting tightly of spheroid and valve seat insert, and namely plays initial seal action.The cross section of valve seat is equivalent to a piston, by the design that changes valve seat can change the medium power on the valve seat of acting on or size, the differential pressure area that increases valve seat can increase the thrust of medium.For the spheroid that improves ball valve and the sealability between the valve seat insert, act on valve seat medium power behind by increasing and namely can realize.Yet it is larger to act on valve seat medium power behind, and the adhesive force between spheroid and the valve seat insert is larger, and the frictional force between them is also larger, just needs larger steering force during Open valve, perhaps needs larger driving mechanism.In addition, when the sealing force between spheroid and the valve seat insert is excessive, when Open valve, cause easily the damage of valve sealing face, particularly when containing solid particle in the medium, easier damage.In a word, from improving the angle of valve base seal property, need to increase valve seat medium thrust behind, but, from the open and close torque that reduces valve and the angle that prevents the damage of sealing surface, need to reduce valve seat medium thrust behind, therefore, this is conflict, and this contradiction is perplexing the design of ball valve for a long time.
Summary of the invention
For the deficiency that prior art exists, the purpose of this utility model is to provide a kind of seal reliable and the little ball valve of open and close torque.
For achieving the above object, the utility model provides following technological scheme: a kind of little ball valve of reliable open and close torque that seals, comprise the valve body with valve pocket, place the spheroid of valve pocket inside, and the valve rod that spheroid is connected and place valve body and spheroid between valve seat sealing mechanism, the valve pocket both sides respectively with inlet passage and outlet passage UNICOM, described valve stem part is placed on the valve body outside, the valve body outside is provided with the Pneumatic actuator of actuate valve stem rotation, it is characterized in that: described valve seat sealing mechanism comprises ring valve holder assembly and three-way diverter valve, described body cavity wall is provided with opening towards the ring valve holder assembly chamber of spheroid, the relative spheroid of described valve component is slidably disposed in the ring valve holder assembly chamber, described valve component and ring valve holder assembly chamber air-tight fit consist of similar piston structure, a described valve body dorsad side of spheroid is provided with the pretension elastic component, described valve body is provided with and the valve component valve support chamber passage that is connected of the ring valve holder assembly chamber conducting of spheroid one side dorsad, three interfaces of described three-way diverter valve respectively with the valve support chamber passage, inlet passage and outlet passage UNICOM, under the valve closing state, described inlet passage is through three-way diverter valve and described valve support chamber passage UNICOM, when valve opening, described valve support chamber passage is through three-way diverter valve and outlet passage UNICOM.
By adopting technique scheme, be that ball valve is when closing when spheroid is in closed position, in order to ensure the valve reliable sealing, handle three-way diverter valve, make valve support chamber passage and inlet passage UNICOM and disconnect with outlet passage, at this moment, the medium of valve inlet side elevated pressures enters into ring valve holder assembly chamber, pressure medium promotes valve component and is affixed to spheroid, thereby forms tight sealing.When needs are opened, switching three-way selector valve at first, make valve support chamber passage and outlet passage UNICOM and disconnect with inlet passage, at this moment, the pressure that pressure in the ring valve holder assembly chamber and valve export side are lower is identical, the pressure of valve component both sides is in a basic balance, the pressure that valve component is affixed to spheroid only comes from the pretension elastic component, and the elasticity pretightening force of pretension elastic component is usually less, at this moment, valve component is very little to pressure and the sealing force of spheroid, therefore the frictional force of sealing surface is also very little, can adopt less torque force to open ball valve, Pneumatic actuator Open valve that namely can selection of small, reduce the volume of valve, reduced cost; In addition, because when Open valve, the sealing force of valve component and spheroid is very little, therefore, is not easy to cause the damage of ball seal face and valve seat insert, has prolonged working life, solved the contradiction that opens and closes between torsion and the ball valve sealing performance.
The utility model further is set to: described ring valve holder assembly chamber is that the approximate rectangular annular groove in cross section consists of, described valve component comprises sectional shape and annular groove cross section the ring valve seat body that matches and the valve seat insert that is embedded on the ring valve seat body, be equipped with seal ring on the inside-and-outside ring sidewall of described ring valve seat body and contact the described piston structure of formation with the sidewall sealing in ring valve holder assembly chamber, sealing surface and the spheroid of described valve seat insert are affixed, described ring valve seat body evenly is provided with a plurality of spring cavity volumes with being provided with on the opposing face of valve seat insert, be provided with Compress Spring in the described spring cavity volume and consist of described pretension elastic component; The pipeline that is provided with annular groove bottom UNICOM near the position in ring valve holder assembly chamber on the described valve body consists of described valve support chamber passage.
By adopting ring valve holder assembly chamber and the valve component of said structure, relatively simple for structure, easy to make.
The utility model further is set to: be provided with filtrating equipment in the pipeline of described three-way diverter valve and inlet passage and outlet passage UNICOM.
Consider under some operating mode, flowing medium in the pipe-line system contains solid impurity, by taking in the pipeline of three-way diverter valve and inlet passage and outlet passage UNICOM, to be provided with filtrating equipment or piston mechanism, can prevent effectively that solid impurity from entering into three-way diverter valve and ring valve holder assembly cavity.
Description of drawings
Fig. 1 is existing ball seat portion structure sectional view;
Fig. 2 is the stressed schematic representation in existing ball seat position;
Fig. 3 is the utility model specific embodiment structural representation;
Fig. 4 is the utility model specific embodiment valve seat pressure control section pipeline connection diagram;
Fig. 5 is the utility model valve seat pressure control section structural representation when being provided with piston.
Embodiment
Such as Fig. 3, shown in 4, seal the little ball valve of reliable open and close torque and comprise the valve body 1 with valve pocket, place the spheroid 2 of valve pocket inside, and the valve rod 3 that spheroid 2 is connected and place valve body 1 and spheroid 2 between valve seat sealing mechanism, the valve pocket both sides respectively with inlet passage 4 and outlet passage 5 UNICOMs, described valve rod 3 parts are placed on valve body 1 outside, valve body 1 outside is provided with the operation drive unit 6 of actuate valve stem 3 rotations, described valve seat sealing mechanism comprises ring valve holder assembly and three-way diverter valve 7, described valve body 1 internal chamber wall is provided with opening towards the ring valve holder assembly chamber 8 of spheroid 2, the relative spheroid 2 of described valve component is slidably disposed in the ring valve holder assembly chamber 8, described valve component and ring valve holder assembly chamber 8 air-tight fit consist of similar piston structure, described valve body 1 a dorsad side of spheroid 2 is provided with pretension elastic component 9, described valve body 1 is provided with and the valve component valve support chamber path 10 that is connected of ring valve holder assembly chamber 8 conductings of spheroid 2 one sides dorsad, three interfaces of described three-way diverter valve 7 respectively with the valve support chamber path 10, inlet passage 4 and outlet passage 5 UNICOMs, under the valve closing state, described inlet passage 4 is through three-way diverter valves 7 and described valve support chamber path 10 UNICOM, when valve opening, described valve support chamber path 10 is through three-way diverter valve 7 and outlet passage 5 UNICOMs.In this specific embodiment, described ring valve holder assembly chamber 8 is that the approximate rectangular annular groove in cross section consists of, described valve component comprises sectional shape and annular groove cross section the ring valve seat body 11 that matches and the valve seat insert 12 that is embedded on ring valve seat body 11, be equipped with seal ring 13 on the inside-and-outside ring sidewall of described ring valve seat body 11 and contact the described piston structure of formation with the sidewall sealing in ring valve holder assembly chamber 8, the sealing surface of described valve seat insert 12 and spheroid 2 are affixed, evenly be provided with a plurality of spring cavity volumes 14 on described ring valve seat body 11 face opposing with being provided with valve seat insert 12, general 3-6 gets final product, be provided with Compress Spring in the described spring cavity volume 14, the free length of Compress Spring slightly is longer than the degree of depth of spring cavity volume 14, and the bottom that two ends are against respectively spring cavity volume 14 and annular groove consists of described pretension elastic component 9.Described pretension elastic component 9 also can such as rubber, consider that the elastic module of spring is large, flexibly movable for other elastic materials consist of, and present embodiment is preferred.In order to prevent that ring valve seat body 11 from coming off, the opening in described ring valve holder assembly chamber 8 preferably is provided with annular pressing plate 16; The pipeline that is provided with annular groove bottom UNICOM near the position in ring valve holder assembly chamber 8 on the described valve body 1 consists of described valve support chamber path 10.Consider under some operating mode, flowing medium in the pipe-line system contains solid impurity, enter in three-way diverter valve 7 and the ring valve holder assembly chamber 8 for fear of impurity and to cause cisco unity malfunction, as shown in Figure 5, be provided with filtrating equipment or piston apparatus 17 in the pipeline of described three-way diverter valve 7 and inlet passage 4 and outlet passage 5 UNICOMs, left and right sides balance by piston in the piston apparatus 17 moves, make the ring valve holder assembly chamber 8 can be as required and the pressure balance of valve inlet end or outlet end, prevent that effectively solid impurity from entering into three-way diverter valve 7 and ring valve holder assembly chamber 8 simultaneously.
These ring valve holder assembly chamber 8 and ring valve seat body 11 sectional shapes that seal the little ball valve of reliable open and close torque are not unique, as long as the central axes of the cylndrical surface at two annular sidewall place or parallel.