Abstract:
A damped actuator for a fluid regulator includes a diaphragm disposed in a housing, and a damper arranged to stabilize movement of the diaphragm in response to changes in pressure inside the housing. The damper includes a ball check valve arranged to allow air to exhaust out of the housing when above a preselected pressure. The damper may include interchangeable components so as to be modifiable to have different set point pressures to achieve different backpressures inside the housing.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 13/618,275, filed Sep. 14, 2012, the entirety of which is incorporated by reference herein. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to fluid regulators, and more particularly, to a damper for use on the actuator of a fluid regulator. 
     BACKGROUND 
     The pressure at which typical gas distribution systems supply gas may vary according to a number of factors. These factors may include, for example, the demands placed on the system, the climate, the source of supply, and/or other factors. However, most end-user facilities equipped with gas appliances such as furnaces, ovens, etc., require the gas to be delivered in accordance with a predetermined pressure, and at or below a maximum capacity of the end-user appliance. Therefore, process fluid regulators are implemented in these distribution systems in order to ensure that the delivered gas meets the requirements of the end-user facilities. Process fluid regulators are also used to regulate the delivery of liquids to achieve similar functionalities. However, fluid regulators can become unstable and begin to flutter, or rapidly oscillate, undesirably in response to changes in pressure of the process fluid. 
       FIG. 1  shows a common process fluid regulator  10 . The fluid regulator  10  includes a regulator body  12 , a control element  14 , and an actuator  16 . The regulator body  12  defines a fluid flow path  18 , a fluid inlet  20 , a fluid outlet  22 , and an orifice  24 . The orifice  24  is operatively disposed between the fluid inlet  20  and the fluid outlet  22 . The fluid flow path  18  extends from the fluid inlet  20 , through the orifice  24 , and to the fluid outlet  22 . The control element  14 , such as a valve disk or plug, shifts to regulate the flow of fluid along the fluid flow path  18  through the orifice  24 . The actuator  16  is operatively connected to the regulator body  12  and the control element  14  to control the position of the control element  14  relative to the orifice  24 . The actuator includes an actuator housing  26 , a diaphragm  28  disposed inside the housing  26 , and an actuator linkage  30  operatively connecting the diaphragm  28  to the control element  14 . The diaphragm  28  separates the housing  26  into a first chamber  32  and a second chamber  34 . The first chamber  32  is hydraulically connected to the fluid outlet  22 , such as by one or more fluid conduits  35  extending from the first chamber  32  to a location in the fluid flow path  18  downstream of the orifice  24 , to sense a fluid pressure at the fluid outlet  22 . The second chamber  34  is hydraulically connected to the surrounding ambient atmosphere. The linkage  30  includes a lever  36  having a first end operatively connected to the diaphragm  28  and a second end operatively connected to a valve stem  38  operatively connected to the control element  14 . Movement of the diaphragm  28  in response to pressure changes at the fluid outlet  22  causes the linkage to shift the valve stem  38 , and thereby the control element  14 , in a manner to maintain a the process fluid pressure within a preselected range at the fluid outlet  22 . 
     The actuator housing  26  is formed of a first or spring case  40  and a second or diaphragm case  42  secured together, such as with one or more bolts connecting respective outer flanges of the first and second cases  40 ,  42 . The diaphragm  28  has an outer peripheral edge clamped between the outer flanges of the spring case  40  and the diaphragm case  42 . The first chamber  32  is defined at least partly by the diaphragm  28  and the diaphragm case  42 . The second chamber  34  is defined at least partly by the spring case  40  and the diaphragm. 
     A first or exhaust vent  44  is formed in the spring case  40  of the housing  26  and extends into the second chamber  34 . The exhaust vent  44  includes a bore  46  extending from an inlet  48  to an outlet  59 . The bore  46  is defined by a sleeve  50  extending along an outer surface of the spring case  40 . The inlet  48  is defined by a first orifice through the spring case  40 . The outlet  49  is defined by a distal end of the sleeve  50 . The exhaust vent  44  hydraulically connects the second chamber  34  to the surrounding ambient atmosphere to allow the second chamber  34  to be maintained at approximately the same pressure as the surrounding ambient atmosphere. 
     A stabilizer valve  52  in the form of a normally-closed check valve is disposed in the exhaust vent  44 . The stabilizer valve  52  is disposed at the inlet  48  and includes a stabilizer, such as a seal disk  54 , a stabilizer guide, such as a rod  56 , and a spring  58 . The rod  56  depends from the inner surface of the sleeve  50  and extends through an aperture through the seal disk  54 . The seal disk  54  is slidingly disposed on the rod  56 . The spring  58  seats against the inner surface of the sleeve  50  and the seal disk  54  and biases the seal disk  54  into sealing engagement with an outer periphery of the inlet  48 . The seal disk  54  slides up along the rod  56  and compresses the spring  58  when air pressure inside the second chamber  34  exceeds a set point force of the spring  58 . 
     The stabilizer valve  52  stabilizes movement of the diaphragm  28  and the control element  14  in response to rapid changes in the outlet fluid pressure at the fluid outlet  22 . For example, without the stabilizer valve  52 , rapid changes in the outlet fluid pressure may cause undesirable oscillation, or flutter, of the diaphragm  28  and the control element  14 . The stabilizer valve  52  helps to reduce such oscillations by limiting exhausting of air through the exhaust vent  44  until the air inside the second chamber  34  reaches a minimum backpressure sufficient to overcome the bias force of the spring  58 . 
     It may sometimes be desirable to adjust a set point pressure or backpressure setting of the stabilizer valve  52 . In the present arrangement, it may be difficult to adjust the backpressure setting without disassembling the spring case  40  from the diaphragm case  42  in order to access the various components of the stabilizer valve  52 . This may require complete shutdown of the process line being controlled by the fluid regulator  10 , which may be undesirable at a time that the backpressure setting needs to be adjusted. 
     A second or control vent  68  is formed in the diaphragm case  42  of the housing  26  and extends into the first chamber  32 . The control vent  68  includes an aperture  70  through the diaphragm case  42  and a socket  72 . The socket  72  is defined by sleeve  74  on the outer surface of the diaphragm case  42 . Preferably, the sleeve  74  is an integral portion of the diaphragm case  42 . The sleeve  74  has a first end surrounding the aperture  70 , a second end spaced distal from the aperture, and interior threads  76  adjacent the second end. Fluid, such as air or liquid, from inside the first chamber  32  may pass through the aperture  70  and the socket  72 . In some applications, the control vent  68  is closed, such as with a plug (not shown) threadedely engaged into the socket  72  at the interior threads  76  at the second end of the sleeve. In other applications, the control vent  68  is operatively connected to a process line, for example, by a conduit  78  operatively connecting the sleeve  74  to a process pipe (not shown) operatively connected to the fluid outlet  22 . In this arrangement fluid pressure inside the first chamber  32  can equalize with fluid pressure at a downstream point in the process pipe through the aperture  70  and the conduit  78 . 
     SUMMARY 
     According to some aspects of the disclosure, an actuator for a fluid regulator includes a diaphragm disposed in a housing, and a damper arranged to stabilize movement of the diaphragm in response to changes in pressure inside the housing. The damper includes a ball check valve arranged to allow air to exhaust out of the housing when above a preselected pressure. 
     In one exemplary aspect, a damped actuator for use with a fluid regulator includes an actuator housing, a diaphragm, an actuator linkage, a vent opening, and a damper operatively coupled to the vent opening. The diaphragm is disposed in the actuator housing and separates the actuator housing into a first chamber and a second chamber. The actuator linkage is operatively connected to the diaphragm and arranged to be operatively connected to a valve stem and to shift the valve stem between a first position and a second position. The vent opening is formed in the actuator housing and extends into at least one of the first chamber and the second chamber. The damper includes a sleeve, a valve seat, a ball, and a spring. The sleeve is operatively coupled to the vent opening and includes a bore. The valve seat is disposed within the bore. The ball is shiftably disposed in the bore and arranged to shift from a closed position seated against the valve seat to an open position disposed away from the valve seat. The spring is positioned to bias the ball toward the valve seat and arranged to allow the ball to shift to the open position when fluid pressure within the selected chamber exceeds a threshold pressure to thereby vent fluid pressure from the selected chamber. 
     According to another exemplary aspect, a fluid regulator includes a regulator body, a control element, and the actuator of the present disclosure. The actuator is preferably operatively connected to the regulator body and the control element to control fluid flow through the regulator body. 
     According to a further exemplary aspect, a method of modifying an actuator for a fluid regulator is disclosed. The actuator includes an actuator housing, a diaphragm, a linkage, and a vent opening formed in the actuator housing. The diaphragm is disposed in the actuator housing and separates the actuator housing into a first chamber and a second chamber. The linkage is operatively connected to the diaphragm and arranged to be operatively connected to a valve stem. The vent defines an air exhaust path out of at least one of the first and second chambers. The method includes steps of providing a damper including a ball check valve, and operatively securing the damper to the vent so as to control flow of air exhausted though the vent. 
     In further accordance with any one or more of the exemplary aspects, a pressure regulator, actuator, damper, and/or system of this disclosure optionally may include any one or more of the following further preferred forms. 
     In some preferred forms, the damper includes a control element in the form of a ball, a valve seat, a spring, and a spring seat. The sleeve may define an inlet, an outlet, and a bore extending from the inlet to the outlet. The valve seat may be disposed in the bore, preferably near the inlet. The spring seat may be disposed in the bore spaced apart from the valve seat toward the outlet. The ball is disposed in the bore and engages the valve seat. The spring may be disposed in the bore between the ball and the spring seat and may engage the ball and the spring seat. The spring may bias the ball against the valve seat in a closed position and allow the ball to separate from the valve seat in response to an increase in air pressure at the inlet in an open position. In the open position, air can travel from the inlet to the outlet, thereby exhausting air from the respective first and/or second chamber. The spring may be a coil spring having a first end and a second end. The first end of the spring may be operatively engaged with the ball, such as by being seated against the ball. A second end of the coil spring may be operatively engaged with the spring seat, such as by being seated against the spring seat. 
     In a still further exemplary aspect, a system for customizing the damper is disclosed in which one or more of the ball, the valve seat, the spring, and the spring seat is/are interchangeable to allow customization of the damper. Any one of two or more different sized valve seats may be selectively coupled to the sleeve, such as by being secured in the outlet of the bore. Each of the different size valve seats may have a first plug body that fits into the bore. The first size valve seat may have a bleed aperture of a first size, and the second size valve seat may have a bleed aperture of a second size. Any one of two or more different sized spring seats may be selectively coupled to the sleeve, such as by being secured in the bore. Each of the different size spring seats may have a second plug body that fits into the bore. The first size spring seat may have a bleed aperture of a first size, and the second size spring seat may have a bleed aperture of a second size. Any one of two or more different sized springs may be selectively operatively disposed to bias the ball. Any one of two or more different sized balls may be selectively operatively disposed in the bore. In this way, the damper may be customized to have any one of several different possible characteristics, such as different backpressure set points and/or flow rate capacity. 
     In some preferred forms, the vent extends into the first chamber through the housing. The vent may be in the form of a port for connection to a control line to a process line extending from the fluid outlet of the regulator. 
     In some preferred forms, the vent extends into the second chamber through the housing. The vent may define a second inlet, a second outlet, and a second bore extending from the second inlet to the second outlet. The actuator further may include a relief valve disposed in the vent. The relief valve may be disposed in the second bore. The sleeve of the damper may be disposed in the second bore. The relief valve may be disposed at the second inlet. The damper may be disposed at the second outlet. The vent may extend from the second chamber to atmosphere. 
     In some preferred forms, a protective cover is disposed across the outlet of the damper. The protective cover may include a neck and shield. The neck may fit into the outlet of the damper. The neck may have outer threads that engage inner threads of the outlet. The neck may be removably secured in the outlet, for example by a threaded connection. The shield may be spaced from the outlet when the neck is operatively disposed in the outlet. One or more air flow passageways may extend through the neck to allow air to exhaust from the outlet. 
     In some preferred forms, the regulator body defines a fluid inlet, a fluid outlet, and a fluid flow path extending from the fluid inlet to the fluid outlet. The control element may be arranged to shift between a first position and a second position within the fluid flow path to control flow of fluid through the fluid flow path. The linkage may operatively connect the control element and/or a valve stem to the diaphragm. The first chamber of the actuator may be operatively coupled with the fluid outlet to be hydraulically connected to an outlet fluid pressure at the fluid outlet, whereby the diaphragm is responsive to changes in the outlet fluid pressure. The second chamber may be hydraulically coupled with ambient atmosphere. 
     Additional optional aspects and features are disclosed, which may be arranged in any functionally appropriate manner, either alone or in any functionally viable combination, consistent with the teachings of the disclosure. Other aspects and advantages will become apparent upon consideration of the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view in partial cut-away of a fluid regulator of the prior art; 
         FIG. 2  is a cross-sectional view of a damper according to the present disclosure; and 
         FIG. 3  is a side view in partial cut-away of a fluid regulator having a damped actuator including dampers according to the present application. 
     
    
    
     DETAILED DESCRIPTION 
     Turning now to the present disclosure,  FIG. 2  shows a damper  100  for an actuator, such as the actuator  16  on the fluid regulator  10 . The damper  100  includes a sleeve  102  and a ball check valve  104  operatively carried by the sleeve  102 . The sleeve  102  defines a bore  106  extending from an inlet  108  to an outlet  110 . The ball check valve  104  is arranged to allow fluid, such as air or water, to travel through the bore  106  from the inlet  108  to the outlet  110  when a minimum backpressure is reached on the inlet side of the ball check valve  104 . 
     The ball check valve  104  includes a flow control member in the form of a ball  111 , a valve seat  112 , a spring  114 , and a spring seat  116 . The valve seat  112  is disposed in the bore  106 , preferably at the inlet  108  of the bore  106 . The spring seat  116  is disposed in the bore  106  spaced apart from the valve seat  112  toward the outlet  110 . The ball  111  is shiftably disposed in the bore  106 . The ball  111  releasably sealingly engages the valve seat  112  and is arranged to shift between a closed position seated against the valve seat  112  and an open position spaced away from the valve seat  112 . The spring  114  is positioned to bias the ball  111  toward the valve seat  112  and arranged to allow the ball  111  to shift to the open position when fluid pressure at the inlet  108  exceeds a threshold pressure, or set point pressure, to thereby vent fluid pressure through the bore  106  to the outlet  110 . The spring  114  is disposed in the bore  106  between and engaging against the ball  111  and the spring seat  116 . The spring  114  biases the ball  111  against the valve seat  112  in a normally closed position. The spring  114  allows the ball  111  to disengage from the valve seat  112  in response to increased backpressure at the inlet  108  when the backpressure exceeds the set point pressure resulting from a spring force of the spring  114 . When the pressure at the inlet  108  falls below the set point pressure, the spring  114  resiliently urges the ball  111  back into engagement with the valve seat  112 . Thus, the ball check valve  104  allows fluid to pass through the bore  106  from the inlet  108  to the outlet  110  and prevents fluid from passing the opposite direction through the bore  106  from the outlet  110  to the inlet  108 . 
     The valve seat  112  has a body that is disposed in the inlet  108  to the bore  106 . The body has in inner side facing into the bore  106  toward the spring seat  116  and an outer side facing out of the inlet  108 . The valve seat  112  includes a bleed aperture  120  extending from the outer side to the inner side, and a seating surface  118  disposed on the inner side surrounding the bleed aperture  120 . The seating surface  118  is adapted to sealingly engage the ball  111  and preferably is formed by a recessed surface sized to partly receive the ball  111 , such as a recessed frustoconical surface, disposed on an inner side of the valve seat  112 . 
     The spring seat  116  has a body disposed in the bore  106 . The body has in inner side facing the valve seat  112  and an outer side facing the outlet  110 , at least one bleed bore  126  extending through the body from the inner side to the outer side, and a seating surface  128  on the inner side. The seating surface  128  is formed by a protruding surface, such as an inner annular shoulder in the bleed bore  126  disposed inside the bleed bore  126 . The seating surface  128  is adapted to provide a seating surface against which the spring  114  seats. Additional or alternative air passageways may also be defined through the spring seat  116  to provide additional or alternative bleed passageways. 
     In one arrangement, one or both of the valve seat  112  and the spring seat  116  is integral with the sleeve  102 . 
     In another, separable arrangement, one or both of the valve seat  112  and the spring seat  116  is a separate component from the sleeve  102  that is removably coupled to the sleeve  102 , for example, by being mounted, either permanently or releasably, into the bore  106 . In this separable arrangement, the body of the valve seat  112  is in the form of a plug having an outer peripheral wall extending between the outer side and the inner side, the bleed aperture  120  extends through the plug, and the valve seat is releasably mounted in the bore  106 , for example, by outer threads  122  on the outer peripheral wall that engage inner threads  124  carried by the sleeve  102  at the inlet  108  to the bore  106 , a bayonet connection, a snap-fit connection, or other type of releasable mounting connection. In this, separable arrangement, the valve seat  112  may be one of several interchangeable different size valve seats  112  adapted to be mounted in the bore  106 , each size valve seat  112  having different arrangements, such as different diameter, length, and/or shape bleed apertures  120  and/or seating surfaces  118 , wherein each different size valve seat  112  can be interchangeably mounted in the bore  106 . For example, a first size valve seat  112  may have a bleed aperture  120  having a first diameter, and a second size valve seat  112  may have a bleed aperture  120  having a second bleed diameter different than the first bleed diameter. The spring seat  116  has a body in the form of a plug or disk permanently or releasably mounted in the bore  106 . The spring seat  116  has an outer peripheral wall extending from the inner side to the outer side of the body that engages the inner peripheral surface of the bore  106 . The spring seat  116  may be releasably mounted in the bore  106  by any sufficient mechanism. In the exemplary mechanism, the outer peripheral wall includes an annular projection or lip  130 , the bore  106  includes an inner annular shoulder  132 , the lip  130  engages against the annular shoulder  132 , and a snap ring  134  is adapted to releasably lock the spring seat  116  into engagement against the annular shoulder  132 . However, other mechanisms may also or alternatively be used, such as a threaded connection, a bayonet connection, a snap-fit connection, and/or other locking mechanisms. The spring seat  116  may be one of several different interchangeable size spring seats  116  adapted to be mounted in the bore  106 , each size spring seat  116  having different arrangements, such as different diameter, length, number and/or shape of bleed apertures  126 , wherein each different size spring seat  116  can be interchangeably mounted in the bore  106 . For example, a first size spring seat  116  may have a bleed aperture  126  having a first diameter, and a second size spring seat  116  may have a bleed aperture  126  having a second bleed diameter different than the first bleed diameter. In the separable arrangements, the spring  114  may also be interchangeable with other sized springs  114 . For example, a first size spring  114  having a first spring rate may be interchangeable with a second size spring  114  having a second spring rate different than the first spring rate. The ball  111  may also be interchangeable with other sized balls  111 . For example a first size ball  111  having a first diameter may be interchangeable with a second size ball  111  having a second diameter different than the first diameter. 
     With the separable arrangements, a system for customizing the damper  100  with interchangeable components may be provided, such as by an operator in the field or at a field shop, wherein the system includes a sleeve  102  and one or more interchangeable balls  111 , valve seats  112 , springs  114  and/or spring seats  116  of different sizes and/or configurations as described herein. With the system, an operator may select a size of the ball  111 , the valve seat  112 , the spring  114 , and/or the spring seat  116 , to obtain a selected backpressure and assemble the damper  100  by mounting the selected valve seat  112 , spring  114 , and/or spring seat  116  into the sleeve  102 . The backpressure created by the damper  100  into the respective chamber  32  and/or  34 , i.e., the set point pressure, may be selectably adjusted to be larger or smaller by selecting a particular combination of the different sized balls  111 , spring seats  112 , springs  114 , and valve seats  116 . Thus, interchanging any one of the first and second sized balls  111 , first and second sized valve seats  112 , first and second sized spring seats  116 , and first and second sized springs  114  results in changing the backpressure the damper  100  produces as fluid passes through the ball check valve  104 . 
     A protective cover  140  may optionally be mounted to the damper  100 . The protective cover  140  is adapted, for example, to prevent rain and/or debris from entering into the bore  106  while also allowing fluid to exhaust from the outlet  110 . The protective cover  140  includes a neck  142  having a first end and a second end and a shield  144  disposed at the second end. The neck  142  mounts into the outlet  110  of the bore  106  and has a hollow bore extending from the first end to the second end. The neck may releasably mount into the sleeve with, for example, outer threads  146  at the first end of the neck  142  that engage inner threads  148  formed by the sleeve  102  adjacent the outlet  110 . The shield  144  is in the form of a cover, such as a flat plate or curved bowl, that covers the second end of the hollow bore. One or more vent apertures  150  through the neck  142  are arranged to allow air exhausting from through the bore  106  of the damper  100  to exhaust though the protective cover  140  to atmosphere. The vent apertures  150  are disposed adjacent an underside of the shield  144 , preferably within a recess formed in the underside of the shield  144 . The shield  144  prevents or limits rain and/or debris from passing through the vent apertures  150  and into the bore  106  of the damper  100 . 
     Outer threads  152  are optionally disposed on an outer peripheral surface of the sleeve  102 . The outer threads  152  are disposed at the inlet end of the sleeve  102  and may be used to mount the sleeve into a reciprocally threaded socket as discussed hereinafter. 
     Turning now to  FIG. 3 , the damper  100  is shown installed as part of the actuator  16  of the fluid regulator  10  previously described herein, thereby modifying the actuator  16  into a damped actuator. The damper  100  is optionally operatively coupled to either or both of the exhaust vent  44  and the control vent  68 , for example, by operatively coupling the sleeve  102  to the vent opening of the exhaust vent  44  and/or the control vent  68 . 
     At the exhaust vent  44 , for example, the damper  100  is mounted, preferably releasably, in the bore  46 , for example by reciprocal inner threads  154  at the outlet  59  of the bore  46  that engage the outer threads  152  of the sleeve  102 . Thus, the actuator  16  includes the stabilizer valve  52  and the damper  100  to provide additional damping of oscillations. Further, the damper  100  may be retrofitted to an existing actuator and/or fluid regulator, such as the actuator  16  and fluid regulator  10 , by installing the damper  100  into the exhaust vent  44  without taking the fluid regulator  10  out of service. The damper  100  may be selected from a plurality of dampers  100  that are pre-assembled having different sizes or backpressure set points, and/or the ball  111 , valve seat  112 , spring  114 , and/or the spring seat  1116  of the damper  100  may be selected and mounted to the sleeve  102  to provide a selected backpressure set point as described herein before. The protective cover  140  is optionally mounted to the sleeve  102  as previously described to prevent rain and/or debris from entering and possibly fouling the ball check valve  104 . 
     At the control vent  68 , the damper  100  is mounted, preferably releasably, in the socket  72 , for example by threaded engagement between the inner threads  76  at the second end of the sleeve  74  and the outer threads  152  of the sleeve  102 . In this arrangement, the protective cover  140  is not mounted to the sleeve  102 . Rather, the conduit  78  is connected to the sleeve  102 , for example, by threaded engagement of the inner threads  146  to reciprocal outer threads at the end of the conduit  78 . Similar to the damper  100  disposed in the exhaust vent  44 , the damper  100  disposed in the control vent  68  may be custom selected and/or modified to provide one of several selected characteristics, such as a minimum backpressure set point, flow capacity, and the like. 
     Other components of the fluid regulator  10  are identical as previously described and known in the art, and are not repeated here, but reference is made to such description. However, the damper  100  may be used in combination with other types and styles of fluid regulators and/or actuators in accordance with the present disclosure. Thus, the disclosure is not limited to the specific type, style, or size of the fluid regulator and/or actuator described herein, it being understood that the particular type of fluid regulator and actuator described herein are exemplary only. 
     A method of modifying an actuator of the prior art, such as the actuator  16 , to include one or more of the dampers  100 . For example, in a first step, a damper  100  is selected and/or customized to provide one of a plurality of different backpressure set points as described previously herein. Thereafter, the damper  100  is mounted at the exhaust vent  44  or the control vent  68  so as to control the flow of fluid through the respective vent. Preferably, the sleeve  102  of the damper  100  is mounted into the respective vent  44  and/or  68 , for example, by engaging the threads  152  to the threads  76  or  154 . 
     Each of the optional arrangements described herein may be arranged in any set of combinations or permutations sufficient to provide any combination of one or more functionalities suggested by the description provided herein. Further, it is understood that each of the features disclosed with respect to each exemplary arrangement may be combined in any functional combination, such as to provide any useful combination of functionalities as would be understood by a person of ordinary skill. 
     The damper  100  may be useful in some arrangements to provide additional damping to a fluid regulator and/or actuator. The damper  100  may be useful in some arrangements to allow a fluid regulator and/or actuator to be field adjusted in a way to reduce and/or control oscillation or flutter of the diaphragm and/or the control element. Other uses and/or benefits not listed herein may also or alternatively be provided by these and/or other arrangements of the damper, actuator, and/or fluid regulator disclosed herein. 
     Numerous modifications to the damper, actuator, and/or fluid regulator disclosed herein will be apparent to those skilled in the art in view of the foregoing description. Accordingly, this description is to be construed as illustrative only and is presented for the purpose of enabling those skilled in the art to make and use the invention and to teach the preferred mode of carrying out same. The exclusive rights to all modifications within the scope of the disclosure and the appended claims are reserved.