Patent Publication Number: US-2022228674-A1

Title: Gate valve indicator devices for oil and gas applications

Description:
TECHNICAL FIELD 
     This disclosure relates to indicator devices for indicating a configuration of a gate valve, such as indicator devices for indicating whether a gate valve with a mechanical slab, non-rising stem design is open or closed. 
     BACKGROUND 
     During operation of a gate valve with a mechanical slab, non-rising stem design, several field issues can arise when the state of the gate valve (for example, the extent to which the gate valve is open) is unknown to a field operator. For example, such gate valves may be installed at wellhead equipment and provide no visible indication of the state of the gate valve. In some cases, the unknown state of the gate valve may require an intervention (for example, a manipulation of the gate valve) that compromises the safety of the field operator, the functionality of the gate valve, or the efficiency of a process carried out at the wellhead equipment. 
     SUMMARY 
     This disclosure relates to an indicator device for indicating a configuration of a gate valve (for example, the extent to which the gate valve is open). The gate valve includes a non-rising valve stem and a mechanical slab, and the indicator device is operable to indicate the configuration of the gate valve based on a rotational degree of the valve stem and a corresponding position of the slab. In this manner, the indicator device can indicate whether the gate valve has a closed configuration in which the slab is located at a reference position within a body of the gate valve or has an open configuration in which the slab is offset from the reference position within the body of the gate valve. The indicator device includes a gear mechanism that couples the valve stem of the gate valve to a gauge that displays an indicator of the gate valve configuration to a field operator in a safe and straight-forward manner. The gauge may be an analog gauge or a digital gauge. In some embodiments, the indicator device further includes a transmitter that can wirelessly transmit a signal corresponding to a rotational position of the valve stem and a corresponding configuration of the gate valve. 
     In one aspect, an indicator device is provided for indicating a configuration of a gate valve. The indicator device includes a cam that is coupled to a valve stem of the gate valve such that rotation of the valve stem causes rotation of the cam. The indicator device further includes a gear that is coupled to the cam such that rotation of the cam causes movement of the gear and a gauge along which the gear is movable. The gauge displays an indicator that corresponds to the configuration of the gate valve based on a first position of the gear and a second position of the valve stem. 
     Embodiments may provide one or more of the following features. 
     In some embodiments, the configuration of the gate valve is an open configuration or a closed configuration. 
     In some embodiments, the configuration of the gate valve is based on a third position of a slab of the gate valve that is coupled to the valve stem. 
     In some embodiments, the valve stem is a non-rising valve stem. 
     In some embodiments, the gear is configured to be rotated by the cam. 
     In some embodiments, the gear includes multiple gear teeth and the cam includes an indexer. 
     In some embodiments, the gear is configured to translate along the gauge. 
     In some embodiments, the gauge is coupled to multiple teeth that are arranged adjacent to the gear. 
     In some embodiments, the gauge is an analog gauge. 
     In some embodiments, the gauge includes a scale along which the indicator is movable. 
     In some embodiments, a first end of the scale corresponds to a fully open configuration of the gate valve and a second end of the scale corresponds to a closed configuration of the gate valve. 
     In some embodiments, the indicator includes a line. 
     In some embodiments, the indicator device further includes a transmitter that is configured to wirelessly transmit a signal corresponding to the configuration of the gate valve. 
     In some embodiments, the gauge is a digital gauge. 
     In another aspect, a system includes a gate valve and an indicator device for indicating a configuration of the gate valve. In some embodiments, the indicator device includes a cam that is coupled to a valve stem of the gate valve such that rotation of the valve stem causes rotation of the cam. The indicator device further includes a gear that is coupled to the cam such that rotation of the cam causes movement of the gear and a gauge along which the gear is movable. The gauge displays an indicator that corresponds to the configuration of the gate valve based on a first position of the gear and a second position of the valve stem. 
     Embodiments may provide one or more of the following features. 
     In some embodiments, the configuration of the gate valve is an open configuration or a closed configuration. 
     In some embodiments, the valve stem is a non-rising valve stem. 
     In some embodiments, the gauge is an analog gauge. 
     In some embodiments, the gauge is a digital gauge. 
     In another aspect, a method of indicating a configuration of a gate valve includes securing a cam of an indicator device to a valve stem of the gate valve, rotating the valve stem of the gate valve and the cam of the indicator device, moving a gear of the indicator device along a gauge of the indicator device in response to rotation of the cam, detecting a position of the gear along the gauge, and displaying an indicator on the gauge that corresponds to the configuration of the gate valve based on a first position of the gear and a second position of the valve stem. 
     The details of one or more embodiments are set forth in the accompanying drawings and description. Other features, aspects, and advantages of the embodiments will become apparent from the description, drawings, and claims. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a front view of a system including an indicator device installed to a gate valve with a mechanical slab, non-rising stem design. 
         FIG. 2  is a cross-sectional, cutaway view of the indicator device and the gate valve of  FIG. 1 , with the gate valve in a fully open configuration. 
         FIG. 3  is a cross-sectional, cutaway view of the indicator device and the gate valve of  FIG. 1 , with the gate valve in a closed configuration. 
         FIG. 4  is a front cutaway view of the indicator device of  FIG. 1 . 
         FIG. 5  is a flow chart illustrating an example method of indicating a configuration of a gate valve with the indicator device of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-4  illustrate an example indicator device  100  that is designed to indicate a configuration of a gate valve  106  (for example, the extent to which the gate valve  106  is open). The gate valve  106  may be embodied as a mechanical slab gate valve with a non-rising stem design and may be produced by any manufacturer of such valves. When the indicator device  100  is installed to the gate valve  106 , the indicator device  100  and the gate valve  106  together form a system  170 . The gate valve  106  may be installed to wellhead equipment located at any well for controlling the flow of production fluids or injected fluids from the well or from an injection plant. The gate valve  106  includes a non-rising valve stem  102  and a mechanical slab  104 , and the indicator device  100  is operable to indicate the configuration of the gate valve  106  based on a rotational degree of the valve stem  102  and a corresponding position of the slab  104 . In addition to the valve stem  102  and the slab  104 , the gate valve  106  includes a lower body  108 , an upper body  110 , and a wheel  112  (for example, a hand wheel). 
     The lower body  108  defines an internal fluid channel  114  through which fluid can flow when the gate valve  106  has an open configuration. The lower body  104  is equipped with flanges  172  for connecting the gate valve  106  to an inflow line and an outflow line (for example, represented by arrows  116 ,  118 ). The lower body  108  is also equipped with a label  174  (for example, a marking tag) on which manufacturing information (for example, date of manufacture, size, and trim features) may be printed or hand-marked. The upper body  110  includes a bonnet  120  and a cap  122  and is secured to the lower body  108  at fasteners  124 . The upper body  110  surrounds the valve stem  102  and the slab  104  and supports the indicator device  100 . 
     Referring particularly to  FIGS. 2 and 3 , the valve stem  102  is rotatable and is connected to the slab  104  at threads such that rotation of the valve stem  102  about an axis  126  (for example, an axis coming out of the page in  FIGS. 2-4 ) causes vertical movement of the slab  104 . For example, the slab  104  may be moved to completely, vertically align an opening  160  of the slab  104  with a seat  178  along the fluid channel  114  to fully open the fluid channel  114  to fluid flow or moved to completely, vertically offset the opening  160  of the slab  104  from the seat  178  along the fluid channel  114  such that a wall  168  of the slab  104  fully closes off (for example, blocks) the fluid channel  114  to fluid flow. The slab  104  may also be moved to an intermediate position in which the fluid channel  114  is partially open to fluid flow. The wheel  112  is supported above the indicator device  100 . Accordingly, the gate valve  106  further includes a coupling member  128  that is connected to the valve stem  102  such that rotation of the wheel  112  causes rotation of the valve stem  102 . 
     Referring particularly to  FIG. 4 , the indicator device  100  includes a housing  130  that surrounds a portion of the valve stem  102  (for example, or an adaptor that is coupled to the valve stem  102 ) and that is supported on the upper body  110  of the gate valve  106 . The indicator device  100  further includes a cam  132  that is connected to the valve stem  102 . The cam  132  includes a ring  134  that is fixedly attached to the valve stem  102  such that the cam  132  rotates with the valve stem  102 . The cam  132  also includes an indexer  136  (for example, a tooth) that extends from the ring  134 . The indicator device  100  also includes a rotatable gear  138  that is coupled to the indexer  136  of the cam  132  at gear teeth  140 . 
     The indicator device  100  further includes a gauge  142  (for example, an analog gauge) that is coupled to the gear  138  at a row of indicator teeth  144 . In addition to the indicator teeth  144 , the gauge  142  includes a body  146  that supports the indicator teeth  144 , a display  148  that shows a movable indicator  150  (for example, a visible line), and a scale  152  that indicates a rotational position of the valve stem  102 . In some examples, the rotational position may be provided as a number of rotations of the valve stem  102  (for example, with respect to a reference rotational position) in a first direction  164  (for example, clockwise) or a second, opposite direction  166  (for example, counterclockwise) about the axis  126 . The rotational position ranges from a fully open configuration of the gate valve  106  (for example, corresponding to complete alignment of the opening  160  of the slab  104  with the fluid channel  114 ) to a closed configuration of the gate valve  106  (for example, corresponding to a complete offset of the opening  160  of the slab  104  with respect to the fluid channel  114 ). In some embodiments, placing the gate valve  106  in the fully open configuration may require several complete turns (for example, 360 degree turns) of the valve stem  102  in one of the directions  164 ,  166 . Similarly, adjusting the gate valve  106  from the fully open configuration to the closed configuration may require the same number of complete turns of the valve stem  102  in the other, opposite direction  164 ,  166 . As the gear  138  is rotated due to movement of the valve stem  102 , the gear  138  translates along the row of indicator teeth  144 . A point of contact  158  between one of the gear teeth  140  and one of the indicator teeth  144  determines a position of the indicator  150 . In some embodiments, the point of contact  158  may be detected by gear threads. 
     Presentation of the indicator  150  at the display  148  can provide an indication (for example, a visual indication) of the gate valve configuration to a field operator in a safe and straight-forward manner. In some embodiments, the indicator device  100  is additionally or alternatively equipped with a transmitter  162  that can wirelessly transmit data containing the rotational position of the valve stem  102  and, accordingly, the configuration of the gate valve  106 , to a receiver (for example, located at a control room). 
     In some embodiments, an indicator device that is otherwise substantially similar in construction and function to the indicator device  100  can additionally or alternatively include a digital gauge (for example, including a digital display and a visible, digital indicator) instead of the analog gauge  142  (for example, including the analog display  148  and the movable indicator  150 ). In some embodiments, the digital gauge may not include the scale  152  and the indicator  150  and instead display a number on the display  148  that corresponds to a rotational position of the valve stem  102  (for example, a number that corresponds to a number along the scale  152  of the analog gauge  142 ). In some embodiments, the digital gauge may alternatively or additionally display a textual description of the configuration of the gate valve  106  that reads “Fully open,” “Partially open,” or “Closed.” Such textual descriptions may correspond to a rotational position of the valve stem  102  that falls within predetermined position ranges. In other embodiments, the textual description may alternatively or additionally display a number of rotations of the valve stem, depending on the gate valve design. 
     The indicator device  100  can be easily installed to the gate valve  106 . For example, the wheel  112  can be operated to fully open or to close the gate valve  106  until a positive stop is achieved. The indicator  150  may then be reset to a position that corresponds respectively to the fully open or closed configuration of the gate valve  106 , and the wheel  112  may be removed from the upper body  110 . The indicator device  100  may then be installed to the upper body  110  by sliding the housing  130  over the valve stem  102  (for example, or an adapter coupled to the valve stem  102 ). The wheel  112  may then be reinstalled to the upper body  110 , and the gate valve  106  and the indicator device  100  can be operated. 
       FIG. 5  is a flow chart illustrating an example method  200  of indicating a configuration of a gate valve (for example, the gate valve  106 ). In some embodiments, the method  200  includes a step  202  for securing a cam (for example, the cam  132  of an indicator device (for example, the indictor device  100 ) to a valve stem (for example, the valve stem  102 ) of the gate valve. In some embodiments, the method  200  further includes a step  204  for rotating the valve stem of the gate valve and the cam of the indicator device. In some embodiments, the method  200  further includes a step  206  for moving a gear (for example, the gear  138 ) of the indicator device along a gauge (for example, the gauge  142 ) of the indicator device in response to rotation of the cam. In some embodiments, the method  200  further includes a step  208  for detecting a position of the gear along the gauge. In some embodiments, the method  200  further includes a step  210  for displaying an indicator (for example, the indicator  150 ) on the gauge that corresponds to the configuration of the gate valve based on a first position of the gear and a second position of the valve stem. 
     While the indicator device  100  has been described and illustrated with respect to certain dimensions, sizes, shapes, arrangements, and methods  200 , in some embodiments, an indicator device that is otherwise substantially similar in construction and function to the indicator device  100  may include one or more different dimensions, sizes, shapes, arrangements, and configurations, or may be utilized according to different methods. Accordingly, other embodiments are also within the scope of the following claims.