Abstract:
A self-operated pressure transmission type of pressure reducing valve with corrugated pipe has an upper cover, a cylinder, a lower cover, a sealing board, a sealing sleeve, a first and second nut, and an upper valve rod. The pressure reducing valve needs no external driving force. It only needs a power-saving product which can automatically adjust the pressure according to the pressure change of the adjusted object. It has multiple functions such as measuring, implementing and controlling pressure, and it solves the problems in the operation process of the conventional pressure reducing valve.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a pressure reducing valve structure. 
       BACKGROUND OF THE INVENTION 
       [0002]    The fluid control of the piping system in the fields of petroleum, chemicals, metallurgy and heating and warming needs to apply the effect of pressure reducing, pressure stabilizing, pressure staticizing and differential pressure control, however the conventional pressure reducing valves have such shortages: 
         [0003]    Thin film plate type: it is easy to age, it can not resist temperature over 150° C. and can not resist pressure over 1.6 MPa, the stroke control of the valve flap is short, the extent of the pressure adjustment is narrow. 
         [0004]    Spring type: it can not realize pressure stabilizing and pressure staticizing. The range of the application field is narrow. 
         [0005]    Piston type: the piston is easy to be stuck, the friction force is great, it is not sensitive, the adjustment extent is narrow, it only can reduce the dynamic pressure but can not reduce the static pressure, the control is not reliable, the pressure adjustment is not precise. 
         [0006]    Corrugated pipe type: the design of the traditional corrugated pipe is not advanced. 
         [0007]    Lever type: the range of the application field is narrow. 
       SUMMARY OF THE INVENTION 
       [0008]    The object of the present invention is to design a self-operated pressure transmission type of pressure reducing valve with corrugated pipe, which has a reliable working stability, long working life, wide application range and needs no external driving force. 
         [0009]    The present invention disposes a valve seat on a valve body, and a spool is disposed on the valve seat and connected to the lower end of a lower valve rod, said lower valve rod passes through and disposed in a valve cover above the valve seat, the upper end of said lower valve rod is connected to an upper valve rod with connecting member; said upper valve rod is movable up and down and supported by a housing, the upper end of said upper valve rod is connected to the upper end of said housing with an regulating nut and a spring, a pressure guiding pipe is connected between said housing and the valve seat; said housing comprises an upper cover, a cylinder and a lower cover, a lower housing inlet is connected to the side wall of the lower cover, an upper housing inlet is connected to the side wall of the upper cover or the side wall of the cylinder, the upper cover and the lower cover are respectively and hermetically connected to the upper and the lower ends of the cylinder, a sealing board is transversely disposed between the cylinder and the lower cover, the center of said sealing board has a through hole; a sealing sleeve is disposed in the cylinder, a corrugated pipe which bears high pressure is disposed outside of the sealing sleeve, the upper and lower ends of the corrugated pipe are respectively and hermetically connected to the sealing sleeve and the sealing board, a first nut for connecting the upper valve rod is fixed above the bottom of said sealing sleeve, and a second nut for connecting the lower valve rod is fixed beneath the bottom of said sealing sleeve; the lower valve rod is thread joint with the second nut; the first nut is thread joint with the lower end of a sealing nut of the corrugated pipe of the upper valve rod; the sealing corrugated pipe of the upper valve rod is disposed between the sealing sleeve and the upper valve, the upper end of which is hermetically connected in the upper cover, the lower end of which is hermetically fixed to the sealing nut of the corrugated pipe of the upper valve rod; said corrugated pipe which bears high pressure, sealing corrugated pipe of the upper valve rod, sealing sleeve and the cylinder are respectively coaxially disposed with the upper valve rod. 
         [0010]    In operation, there is a space between the upper housing and the lower housing for the adjustment of up and down movement. 
         [0011]    The present invention applies the corrugated pipe which bears high pressure to seal and isolate the upper and lower housing, and applies the sealing corrugated pipe of the upper valve rod to seal and isolate the upper and lower valve rod, and applies the corrugated pipe made of the stainless steel of 316L type or other alloy as the pressure transmission type of adjustment and balancing element, the pressure of the object through the upstream or the downstream is transmitted to the upper housing or the lower housing through the guiding pipe equipped with a drain and pressure releasing filter, the corrugated pipe is pressed to stretch out and draw back, and causes the spool move, so the quantity of flow is changed to adjust the upstream pressure or the downstream pressure and to adjust the differential pressure, thereby it can realize the effects of pressure reducing, pressure stabilizing, pressure staticizing and controlling differential pressure by self-operated. 
         [0012]    The present invention needs no external driving force, it only needs a power-saving product which can automatically adjust the pressure according to the pressure change of the pressure adjusted object, it has multiple functions such as measure, implement and control, and it will solve the problems in the operation process of the conventional pressure reducing valve. It has the advantages such as high temperature resistant (≦400° C.), high pressure resistant (≦25 MPa), the adjustment extent is wide, it can realize the precise control of pressure stabilizing, pressure staticizing and differential pressure; it is adaptable for horizontal-mounted or reverse-mounted, the leakage is completely avoided, the corrugated pipe made of the stainless steel 316L or other alloy is applied as the pressure transmission type of adjustment and balancing element. It has the features such as reliable working stability, long working life and wide application range. The present invention is widely used the fluid pressure of the piping system in the fields of petroleum, chemicals, metallurgy and heating and warming: the effect of pressure reducing, pressure stabilizing and pressure staticizing and the differential pressure control can be realized, the adaptable objects can be water, air, steam, ammonia, nitrogen, acetic acid and corrosive objects such as urea, the adaptable temperature is from −253° C. to +650° C. 
         [0013]    Further, the outer periphery of the sealing board of the present invention is hermetically fixed to the inner side wall of the cylinder. 
         [0014]    Said upper valve rod is coaxially disposed with said lower valve rod. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]      FIG. 1  is a structural view of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0016]    As showed in  FIG. 1 , a valve seat  2  is disposed in the valve body  1 , a spool  3  is disposed above the valve seat and connected to a lower end of the lower valve rod  4 , after the lower valve rod  4  passing through the supporting shelf  5 , then it will pass through the sealing corrugated pipe  6  of the lower valve rod and disposed therein, further it is hermetically connected to the sealing corrugated pipe  6  of the lower valve rod, the upper end of the lower valve rod  4  sequentially passes through and disposed in the valve cover  7 , connecting nut  8 , lower cover  9  and sealing board  10 . The connecting nut  8  is connected between the lower valve rod  4  and an implementing mechanism which controls the up and down movement of the spool. 
         [0017]    The housing is mainly composed of the upper cover  18 , housing  16  and the lower cover  9 , a lower housing inlet  28  is connected to the side wall of the lower cover  9 , an upper housing inlet  30  is connected to the side wall of the upper cover  18  or the side wall of the cylinder  16 , the upper cover  18  and the lower cover  19  are respectively and hermetically connected to the upper and lower ends of the cylinder  16 . A sealing board  10  is transversely disposed between the cylinder  16  and the lower cover  9 , the center of the sealing board  10  has a through hole for the lower valve rod  4  to freely move up and down, moreover, the outer periphery of the sealing board  10  is hermetically fixed to the side wall of the cylinder  16 . 
         [0018]    A sealing sleeve  17  is disposed in the cylinder  16 , a corrugated pipe  14  which bears high pressure is disposed outside of the sealing sleeve  17 , the upper and lower ends of the corrugated pipe  14  are respectively and hermetically connected to the sealing sleeve  17  and the sealing board  10 . 
         [0019]    A first nut  12  for connecting the upper valve rod is welded above the bottom of the sealing sleeve  17 , and a second nut  11  for connecting the lower valve rod is welded beneath the bottom of the sealing sleeve  17 , the upper end of the lower valve rod  4  is connected in the second nut  11 , the first nut  12  is connected to the bolt of the lower end of the sealing nut  13  of the corrugated pipe of the upper valve rod with the inner thread of the first nut  12 , the lower end of the upper valve rod  20  is thread joint with the sealing nut  13  of the corrugated pipe of the upper valve rod. 
         [0020]    A sealing corrugated pipe  15  of the upper valve rod is disposed between the sealing sleeve  17  and the upper valve rod  20 , the upper end of which is hermetically connected to the upper cover  18 , the lower end of which is hermetically fixed to the sealing nut  13  of the corrugated pipe of the upper valve rod. 
         [0021]    The upper valve rod  4  is coaxially disposed with the lower valve rod  20 , the corrugated pipe  14  which bears high pressure, the sealing corrugated pipe  15  of the upper valve rod, the sealing sleeve  17  and the cylinder  16  are respectively coaxially disposed with the upper valve rod  4  or the lower valve rod  20 . 
         [0022]    The upper valve rod  20  passes through and disposed in the upper cover  18 , the upper end of which is connected to the spring  19  and the regulating nut  21 . 
         [0023]    A piezometer  22  is connected to the inlet of upstream of the valve. 
         [0024]    A valve outlet  23  is disposed on the passageway of the downstream of the valve, a pressure guiding pipe  24  is connected to the valve outlet  23  and is disposed with a ball valve  25 , a filter  26 , and a drain and pressure releasing valve  27 , the upper end of the pressure guiding pipe  24  is connected to a piezometer  32  of the outlet of the downstream of the valve. 
         [0025]    When the downstream pressure is adjusted, the pressure on the pressure guiding pipe  24  is connected to the upper housing inlet  30  through a three-way pipe (as showed in  FIG. 1 ). 
         [0026]    When the upstream pressure is adjusted, the pressure on the pressure guiding pipe  24  is connected to the lower housing inlet  28  through a three-way pipe. 
         [0027]    The working principle of the present invention is: 
         [0028]    (1) the working principle of the downstream pressure adjustment: (please refer  FIG. 1 ) 
         [0029]    After the object passes through the valve  1  with a low-ingress and high-egress manner and throttled by the valve seat  2  and the spool  3 , the upstream pressure P 1  is transferred into the downstream pressure P 2 , at the same time, the downstream pressure P 2  is transmitted into the upper housing  31  of the implementing device with the pressure guiding pipe  24  and then acts on the corrugated pipe  14  which bears high pressure, the corrugated pipe  14  shrinks, the applied force is balanced with the reaction force of the spring  19 , so the relative position of the valve seat  2  and the spool  3  is determined, the downstream pressure P 2  is controlled. When the downstream pressure P 2  is increased, the shrinking force on the corrugated pipe  14  by the downstream pressure P 2  will be increased. At this moment, the shrinking force is greater than the reaction force of the spring, so the spool  3  will close toward the valve seat, until the shrinking force is balanced with the reaction force of the spring  19 . Meanwhile, the flow area between the valve seat  2  and the spool  3  is decreased, and the flow resistance is increased, so the downstream pressure P 2  is decreased to the predetermined value. According to the same principle, when the downstream pressure P 2  is decreased, the acting direction will be opposite to the original direction, that is the working principle of the downstream pressure adjustment. The predetermined value of the downstream pressure P 2  can be adjusted by adjusting the regulating nut  21 . 
         [0030]    (2) the working principle of the upstream pressure adjustment: 
         [0031]    After the object passes through the valve  1  with a low-ingress and high-egress manner and throttled by the valve seat  2  and the spool  3 , the upstream pressure P 1  is transferred into the downstream pressure P 2 , at the same time, the upstream pressure P 1  is transmitted into the lower housing  29  of the implementing device with the pressure guiding pipe  24  and then acts on the corrugated pipe  14  which bears high pressure, the corrugated pipe  14  expands, the applied force is balanced with the reaction force of the spring  19 , so the relative position of the valve seat  2  and the spool  3  is determined, the upstream pressure is controlled. When the upstream pressure P 1  is increased, the expanding force on the corrugated pipe  14  by the upstream pressure P 1  will be increased. At this moment, the expanding force is greater than the reaction force of the spring, so the spool  3  will move opposite the valve seat  2 , until the expanding force is balanced with the reaction force of the spring  19 . Meanwhile, the flow area between the valve seat  2  and the spool  3  is increased, and the flow resistance is decreased, so the upstream pressure P 1  is decreased to the predetermined value. According to the same principle, when the upstream pressure P 1  is decreased, the acting direction will be opposite to the original direction, that is the working principle of the upstream pressure adjustment. The predetermined value of the upstream pressure P 1  can be adjusted by adjusting the regulating nut  21 . 
         [0032]    The working principle of the differential pressure control: 
         [0033]    After the object is throttled through the valve  1  with a low-ingress and high-egress manner and enters the controlled device, the differential pressure of the controlled device are respectively leaded into the upper housing  31  and the lower housing  29  of the valve, a pushing force is generated in upper housing  31  and the lower housing  29  and balanced with the reaction force of the spring  19 , so the relative position of the valve seat  2  and the spool  3  is determined, then the value of the differential pressure ΔP is decided by the relative position. When the controlled differential pressure is changed, the balance of the forces is broken up, so the spool  3  is driven to move, and the resistance coefficient of the valve is changed by the movement of the spool  3 , so the value of the controlled differential pressure will be controlled as a predetermined value. That is the working principle of the differential pressure control. The predetermined value of the differential pressure can be adjusted by adjusting the regulating nut  21 . 
         [0034]    Although the present invention has been described with reference to the preferred embodiments thereof for carrying out the invention, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.