Patent Publication Number: US-2022212237-A1

Title: Simultaneously unblocking multiple valve fittings

Description:
TECHNICAL FIELD 
     This disclosure relates to valves to control fluid flow. 
     BACKGROUND OF THE DISCLOSURE 
     Some valves have components and clearances between components that can become blocked with corrosion or debris over time. Valves can contain valve fittings positioned on an external surface of the valve and located proximal to regions of potential blockages for unblocking these regions of potential blockages. Multiple blockages can occur at the same time in a valve. One or more blockages can cause a valve to fail. 
     SUMMARY 
     This disclosure describes technologies related to methods for simultaneously unblocking multiple blocked valve fittings. Implementations of the present disclosure include a method for simultaneously unblocking the multiple blocked valve fittings. The method includes coupling a tool which unblocks multiple valve fittings simultaneously to a valve. The valve includes a first valve fitting and a second valve fitting. The first valve fitting and the second valve fitting are blocked to fluid flow through the valve. The tool includes a pressure vessel to hold a cleaning fluid. The tool also includes an input conduit fluidically coupled to the pressure vessel. The input conduit flows the cleaning fluid from a cleaning fluid source to the pressure vessel. The input conduit flows a fluid to adjust a pressure of the pressure vessel. The tool includes a first injection conduit having a first injection conduit first end mechanically coupled to the pressure vessel and a first injection conduit second end to mechanically couple to the first valve fitting. The first injection conduit flows the cleaning fluid from the pressure vessel to the first valve fitting. The tool includes a second injection conduit having a second injection conduit first end mechanically coupled to the pressure vessel. The tool includes a second injection conduit second end to mechanically couple to the second valve fitting. The second injection conduit flows the cleaning fluid from the pressure vessel to the second valve fitting. Flowing the cleaning fluid from the cleaning fluid source can include flowing the cleaning fluid through the input conduit into the pressure vessel. The tool is portable. 
     The method for simultaneously unblocking the multiple blocked valve fittings includes simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting. Flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include pressurizing the pressure vessel. 
     Simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include opening a first injection valve positioned in the first injection conduit. The first injection valve controls cleaning fluid flow through the first injection conduit. Responsive to opening the first injection valve, the cleaning fluid flows from the pressure vessel to the first valve fitting. Simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include shutting the first injection valve. Responsive to shutting the first injection valve, the flow of the cleaning fluid stops from the pressure vessel to the first valve fitting. Simultaneously with opening the first injection valve, the method can include opening a second injection valve positioned in the second injection conduit to control cleaning fluid flow through the second injection conduit. Responsive to opening the second injection valve, the cleaning fluid flows from the pressure vessel to the second valve fitting. The method includes shutting the second injection valve. Responsive to shutting the second injection valve, flow of the cleaning fluid stops from the pressure vessel to the second valve fitting. 
     Simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include a first pressure gauge fluidically coupled to the first injection conduit downstream from the first injection valve. Downstream from the first injection valve is away from the pressure vessel. The first pressure gauge monitors a first fluid pressure in the first valve fitting. A second pressure gauge is fluidically coupled to the second injection conduit downstream from the second injection valve. The second pressure gauge monitors a second fluid pressure in the second valve fitting. Simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include, before opening the first injection valve, sensing a first injection conduit pressure with the first pressure gauge. The method includes determining that the first injection conduit pressure is less than the minimum injection pressure. In response to determining that the first injection conduit pressure is less than the minimum injection pressure; the method includes opening the first injection valve positioned in the first injection conduit. The method includes sensing the first injection conduit pressure is at least the minimum injection pressure. Responsive to sensing the first injection conduit pressure is at least the minimum injection pressure, the method includes shutting the first injection valve. Simultaneously before opening the second injection valve, the method includes sensing a second injection conduit pressure with the second pressure gauge. The method includes determining that the second injection conduit pressure is less than the minimum injection pressure. In response to determining that the second injection conduit pressure is less than the minimum injection pressure; the method includes opening the second injection valve positioned in the second injection conduit. The method includes sensing the second injection conduit pressure is at least the minimum injection pressure. Responsive to sensing the second injection conduit pressure is at least the minimum injection pressure, the method includes shutting the second injection valve. 
     Pressurizing the pressure vessel, where the tool includes a manual hand pump, includes coupling a manual hand pump to the input conduit. Pressurizing the pressure vessel with the manual hand pump includes opening an input pressure isolation valve positioned in input conduit. Pressurizing the pressure vessel with the manual hand pump includes operating a manual hand pump coupled to the input conduit to raise the pressure to a minimum injection pressure. The minimum injection pressure is a minimum pressure necessary to unblock multiple valve fittings simultaneously. Pressurizing the pressure vessel with the manual hand pump includes determining a pressure vessel pressure has reached at least the minimum injection pressure. In response to determining that the pressure vessel pressure has reached at least the minimum injection pressure, pressurizing the pressure vessel with the manual hand pump includes shutting the input pressure isolation valve to maintain the pressure vessel pressure at the minimum injection pressure. 
     The method for unblocking the blocked valve fitting includes, responsive to flowing the cleaning fluid to the valve fitting, unblocking the first valve fitting. 
     The method for unblocking the blocked valve fitting includes, responsive to flowing the cleaning fluid to the valve fitting, unblocking the second valve fitting. 
     Where the tool includes a pressure vessel pressure gauge fluidically coupled to the pressure vessel, the method can include sensing, by the pressure vessel pressure gauge, pressure vessel pressure. 
     The method can include decoupling the tool from the valve. Decoupling the tool from the valve can include decoupling the first injection conduit second end from the first valve fitting and decoupling the second injection conduit second end from the second valve fitting. 
     The method can include determining the first valve fitting and the second valve fitting are blocked to fluid flow through the valve. Determining the first valve fitting and the second valve fitting are blocked to fluid flow through the valve includes opening the first injection valve. The method includes flowing the cleaning fluid through the first injection conduit. The method includes sensing the first injection conduit pressure is at least the minimum injection pressure. The method includes shutting the first injection valve. The method includes sensing a first injection conduit pressure rate decrease over a time period. The method includes comparing the first injection conduit pressure rate decrease to a first injection conduit pressure rate threshold decrease. The method includes determining that the first injection conduit is blocked when the first injection conduit pressure rate decrease is less than the first injection conduit pressure rate threshold decrease. The method includes opening the second injection valve. The method includes flowing the cleaning fluid through the second injection conduit. The method includes sensing the second injection conduit pressure is at least the minimum injection pressure. The method includes shutting the second injection valve. The method includes sensing a second injection conduit pressure rate decrease over the time period. The method includes comparing the second injection conduit pressure rate decrease to a second injection conduit pressure rate threshold decrease. The method includes determining that the second injection conduit is blocked when the second injection conduit pressure rate decrease is equal to or less than the second injection conduit pressure rate threshold decrease. 
     Further implementations of the present disclosure include a method including coupling a first injection conduit to flow a cleaning fluid to a first valve fitting. The first valve fitting is blocked to fluid flow through the valve. The method includes coupling a second injection conduit configured to flow the cleaning fluid to a second valve fitting. The second valve fitting is blocked to fluid flow through the valve. The method includes coupling the first injection conduit to a pressure vessel configured to hold the cleaning fluid. The method includes coupling the second injection conduit to the pressure vessel. The method includes pressurizing the pressure vessel holding the cleaning fluid. 
     The method includes, responsive to pressurizing the pressure vessel, simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting. Simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include a first pressure gauge fluidically coupled to the first injection conduit downstream from the first injection valve. Downstream from the first injection valve is away from the pressure vessel. The first pressure gauge monitors a first fluid pressure in the first valve fitting. A second pressure gauge is fluidically coupled to the second injection conduit downstream from the second injection valve. The second pressure gauge monitors a second fluid pressure in the second valve fitting. Simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include, before opening the first injection valve, sensing a first injection conduit pressure with the first pressure gauge. The method includes determining that the first injection conduit pressure is less than the minimum injection pressure. The method includes, in response to determining that the first injection conduit pressure is less than the minimum injection pressure, opening the first injection valve positioned in the first injection conduit. The method includes sensing the first injection conduit pressure is at least the minimum injection pressure. The method includes, responsive to sensing the first injection conduit pressure is at least the minimum injection pressure, shutting the first injection valve. The method includes, simultaneously before opening the second injection valve, sensing a second injection conduit pressure with the second pressure gauge. The method includes determining that the second injection conduit pressure is less than the minimum injection pressure. The method includes, in response to determining that the second injection conduit pressure is less than the minimum injection pressure, opening the second injection valve positioned in the second injection conduit. The method includes sensing the second injection conduit pressure is at least the minimum injection pressure. The method includes, responsive to sensing the second injection conduit pressure is at least the minimum injection pressure, shutting the second injection valve. The method can include flowing the cleaning fluid from a cleaning fluid source through an input conduit into the pressure vessel. 
     The method includes responsive to flowing the cleaning fluid to the valve fitting, unblocking the first valve fitting. The method includes, responsive to flowing the cleaning fluid to the valve fitting, unblocking the second valve fitting. 
     The method can include opening a first injection valve positioned in the first injection conduit. The first injection valve controls cleaning fluid flow through the first injection conduit. The method includes, responsive to opening the first injection valve, flowing the cleaning fluid from the pressure vessel to the first valve fitting. The method includes shutting the first injection valve. The method includes, responsive to shutting the first injection valve, stopping flow of the cleaning fluid from the pressure vessel to the first valve fitting. The method includes simultaneously with opening the first injection valve, opening a second injection valve positioned in the second injection conduit configured to control cleaning fluid flow through the second injection conduit. The method includes, responsive to opening the second injection valve, flowing the cleaning fluid from the pressure vessel to the second valve fitting. The method includes shutting the second injection valve. The method includes, responsive to shutting the second injection valve, stopping flow of the cleaning fluid from the pressure vessel to the second valve fitting. 
     Pressurizing the pressure vessel can include, where the pressurizing vessel includes an input conduit to flow the cleaning fluid from a cleaning fluid source into the pressure vessel and where the pressurizing vessel includes a pressure vessel pressure gauge fluidically coupled to the pressure vessel, sensing, by the pressure vessel pressure gauge, pressure vessel pressure. The method includes determining that the pressure vessel pressure, by the pressure vessel pressure gauge, is less than or equal to a minimum injection pressure. The minimum injection pressure is a minimum pressure necessary to unblock multiple valve fittings simultaneously. In response to determining that the pressure vessel pressure is less than or equal to a minimum injection pressure, the method includes coupling a manual hand pump to the input conduit. The method includes opening an input pressure isolation valve positioned in input conduit. The method includes operating a manual hand pump coupled to the input conduit to raise the pressure vessel pressure to the minimum injection pressure. The method includes determining a pressure vessel pressure has reached at least the minimum injection pressure by the pressure vessel pressure gauge. In response to determining that the pressure vessel pressure has reached at least the minimum injection pressure, the method includes shutting the input pressure isolation valve to maintain the pressure vessel pressure at the minimum injection pressure. The method includes decoupling the manual hand pump from the input conduit. 
     The method can include decoupling a first injection conduit second end from the first valve fitting. The method can include decoupling a second injection conduit second end from the second valve fitting. 
     The method can include determining the first valve fitting and the second valve fitting are blocked to fluid flow through the valve. The method includes opening the first injection valve. The method include flowing the cleaning fluid through the first injection conduit. The method includes sensing the first injection conduit pressure is at least the minimum injection pressure. The method includes shutting the first injection valve. The method includes sensing a first injection conduit pressure rate decrease over a time period. The method includes comparing the first injection conduit pressure rate decrease to a first injection conduit pressure rate threshold decrease. The method includes determining that the first injection conduit is blocked when the first injection conduit pressure rate decrease is less than the first injection conduit pressure rate threshold decrease. The method includes opening the second injection valve. The method includes flowing the cleaning fluid through the second injection conduit. The method includes sensing the second injection conduit pressure is at least the minimum injection pressure. The method includes shutting the second injection valve. The method includes sensing a second injection conduit pressure rate decrease over the time period. The method includes comparing the second injection conduit pressure rate decrease to a second injection conduit pressure rate threshold decrease. The method includes determining that the second injection conduit is blocked when the second injection conduit pressure rate decrease is equal to or less than the second injection conduit pressure rate threshold decrease. 
     The method can include determining the first valve fitting and the second valve fitting are unblocked to fluid flow through the valve. The method includes opening the first injection valve. The method includes flowing the cleaning fluid through the first injection conduit. The method includes sensing the first injection conduit pressure is at least the minimum injection pressure. The method includes shutting the first injection valve. The method includes sensing a first injection conduit pressure rate decrease over the time period. The method includes comparing the first injection conduit pressure rate decrease to a first injection conduit pressure rate threshold decrease. The method includes determining that the first injection conduit is unblocked when the first injection conduit pressure rate decrease is greater than the first injection conduit pressure rate threshold decrease. The method includes opening the second injection valve. The method includes flowing the cleaning fluid through the second injection conduit. The method includes sensing the second injection conduit pressure is at least the minimum injection pressure. The method includes shutting the second injection valve. The method includes sensing a second injection conduit pressure rate decrease over the time period. The method includes comparing the second injection conduit pressure rate decrease to a second injection conduit pressure rate threshold decrease. The method includes determining that the second injection conduit is unblocked when the second injection conduit pressure rate decrease is equal to or greater than the second injection conduit pressure rate threshold decrease. 
     The details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic of a tool coupled to multiple valve fittings. 
         FIG. 2  is a schematic view of another tool configured to clean multiple valve fittings. 
         FIG. 3  is a schematic of the tool of  FIG. 1  coupled to a manual hand pump. 
         FIG. 4  is a flow chart of an example method of simultaneously cleaning multiple valve fittings. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
     The present disclosure relates to a method of using a tool to simultaneously unblock multiple valve fittings of a valve which are blocked to flow. Some examples of valves that can be blocked to flow are ball valves and gate valves. Valves have components such as valve seats or valve stems that can become blocked. Valve components can become blocked slowly due to corrosion of valve materials or due to buildup of organic or inorganic matter. For example, a valve can fail due to the inability of a valve to change position when operated due to corrosion on a valve stem of the valve. Also, valve components can become blocked by a larger particle or foreign object becoming lodged between components. These types of blockages can cause the blocked valve to fail to function as designed. Alternatively or in addition, a valve can fail because debris can become lodged in a valve seat of the valve resulting in a valve disk or gate&#39;s inability to fully shut. Valves can be equipped with a valve fitting fluidically coupled to the components to allow flow of a fluid from an external source to the component for the purpose of unblocking the component. For example, a valve stem fitting can flow fluid from the external source to the blocked area by the valve stem. 
     The tool that simultaneously unblocks multiple valve fittings includes a pressure vessel, an input conduit, a first injection conduit, and a second injection conduit. The pressure vessel holds a cleaning fluid at a pressure. The input conduit is fluidically coupled to the pressure vessel. When a cleaning fluid source is coupled to the input conduit, the input conduit flows the cleaning fluid from the cleaning fluid source to the pressure vessel. When a pressure source is connected to the input conduit, the pressure source adjusts a pressure of the pressure vessel. The first injection conduit has a first injection conduit first end mechanically coupled to the pressure vessel and a first injection conduit second end mechanically coupled to the first valve fitting. The first injection conduit flows the cleaning fluid from the pressure vessel to the first valve fitting. The second injection conduit has a second injection conduit first end mechanically coupled to the pressure vessel and a second injection conduit second end mechanically coupled to the second valve fitting. The second injection conduit flows the cleaning fluid from the pressure vessel to the second valve fitting. The blocked valve has a blocked first valve fitting and a blocked second valve fitting. The tool simultaneously flows the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting blocked to flow and through the second injection conduit to the second valve fitting blocked to flow. The first valve fitting is unblocked in response to flowing the cleaning fluid to the first valve fitting. The second valve fitting is unblocked in response to flowing the cleaning fluid to the second valve fitting. 
     Implementations of the present disclosure realize one or more of the following advantages. The time required for valve maintenance can be reduced. For example, unblocking multiple blocked valve fittings on a valve simultaneously instead of sequentially can result in reduced equipment down time for maintenance. Valve operational time can be increased. For example, performing frequent cleanings can prevent valve damage that requires systems to be shut down and damaged or permanently blocked valves to be replaced. Additionally, valve life can be increased. For example, valves can be completely unblocking more frequently and cleaning of valve components can be achieved. Also, equipment safety can be improved. For example, proper operation of a valve required for a safety barrier for a high pressure, high temperature, or hazardous fluid can be maintained. 
     Other advantages can include increased personnel safety. For example, the risk of equipment damage causing system failure can be reduced. Additionally, the tool and included components are sized so as to be small and portable. For example, the tool can more easily access difficult to reach valves such as in subsea application, congested areas, and high elevation areas. 
     As shown in  FIG. 1 , a valve fitting unblocking tool  100  simultaneously unblocks a valve  102  with multiple valve fittings  104  blocked to flow. The first valve fitting blocked to flow is valve fitting  104   a . The second valve fitting blocked to flow is valve fitting  104   b . The valve fitting  104  prevents fluids from leaking out of a valve when sealed, but allows fluid to flow into the valve when flushing the valve or out of the valve when bleeding the valve. For example, the valve fitting can be a screw-in connector or a nipple connector. As discussed earlier, the valve fittings  104  are connected to different parts of the valve  102  such as a valve body to block or bleed the valve, the valve seat, or the valve stem. Some examples of valves with valve fittings are ball valves and gate valves. 
     The valve fitting unblocking tool  100  includes a pressure vessel  126 . The pressure vessel  126  receives the cleaning fluid  106 , holds the cleaning fluid  106 , and supplies the cleaning fluid  106  to the valve fittings  104  blocked to flow. The pressure vessel  126  can be pressurized by an external pressure source, as shown in  FIG. 3 . The pressure vessel  126  can be pressurized to between 10,000 pounds per square inch (psi) to 30,000 psi. A typical operating pressure for the valve fitting unblocking tool can be 15,000 psi. The pressure vessel  126  can be a container or housing constructed of a metal, for example steel, a steel alloy, or aluminum and that is fluidically sealed. The pressure vessel  126  can be sized to have different capacities. 
     The pressure vessel  126  receives the cleaning fluid  106  from an external cleaning fluid source  108 . The external cleaning fluid source  108  can be pressurized or un-pressurized depending on the pressure of the pressure vessel  126 . For example, in a pressurized state, the cleaning fluid source  108  can inject the cleaning fluid  108  into the pressure vessel  126 . In this example, the external cleaning fluid source  108  can be another pressure vessel such as a can of cleaning chemicals. Alternatively, in an un-pressurized state, the cleaning fluid source  108  can pour the cleaning fluid  108  into the pressure vessel  126 . For example, the external cleaning fluid source  108  can be a capped fluid container. 
     The cleaning fluid  108  can be water, de-ionized water, or contain additional cleaning agents. Some examples of additional cleaning agents include specialized valve cleaner liquids. Valve cleaner liquids can have additional chemicals that react with the hardened material blocking the valve fittings  104  to dissolve the blockage. The unblocking process can require both high pressure and chemical reaction to clear the blockage. The valve fitting unblocking tool  100  can also be used to pressurize a valve sealant and lubricant. 
     An input conduit  110  is mechanically coupled to the pressure vessel  126 . The input conduit  110  flows a fluid from the external source  108  into the pressure vessel  126 . For example, the external source  108  can contain the cleaning fluid  106  and the input conduit  110  can flow the cleaning fluid  106  from the external source  108  into the pressure vessel  126 . Alternatively or in addition, the external source  108  contain pressurized gas such as air or nitrogen and the input conduit  110  and the input conduit can flow the pressurized gas from the external source  108  into the pressure vessel  126  to adjust a pressure of the pressure vessel  126 . For example, the external source  108  can be a manual hand pump  302 , as shown in  FIG. 3 , to increase the pressure of the cleaning fluid  106  in the pressure vessel  126 . Referring to  FIG. 3 , the manual hand pump  302  is a piston type pump with a piston  304  positioned within a pump body  306 . The piston  304  moves within the pump body  306  to compress the fluid within a volume  308  defined by the piston body  306  and piston  304 . The piston  304  is moved by a piston rod  310  connected to a handle  312 . The handle  312  is moved by an operator. The input conduit  110  can be a solid metal pipe, a braided metal hose, or a synthetic hose. The input conduit  110  can include a fitting (not shown) to couple the input conduit to the external source. For example, the fitting can be a screw-in connector or a nipple connector. 
     Referring to  FIG. 1 , the input conduit  110  can include an input isolation valve  112  to control flow through the input conduit  110 . For example, the input isolation valve  112  can be a ball valve that when in an open position allows flow of the fluid from the external source  108  to the pressure vessel  126  and when in a shut position stops flow of the fluid from the external source  108  to the pressure vessel  126 . 
     Multiple injection conduits are mechanically and fluidically coupled to the pressure vessel  126 . The injection conduits flow pressurized cleaning fluid  106  from the pressure vessel  126  to multiple valve fittings simultaneously. The first injection conduit  114   a  flows the pressurized cleaning fluid  106  from the pressure vessel  126  to the first valve fitting  104   a . The second injection conduit  114   b  flows the pressurized cleaning fluid  106  from the pressure vessel  126  to the second valve fitting  104   b . As shown in  FIG. 2 , the valve fitting unblocking tool  200  can include more than two injection conduits. For example, the valve fitting unblocking tool  200  has a third injection conduit  114   c  that flows the pressurized cleaning fluid  106  from the pressure vessel  126  to a third valve fitting (not shown). Additionally, valve fitting unblocking tool  200  has a fourth injection conduit  114   d  that flows the pressurized cleaning fluid  106  from the pressure vessel  126  to a fourth valve fitting (not shown). 
     Referring to  FIG. 2 , the injection conduits have a first end and a second end. The first end is mechanically and fluidically coupled to the pressure vessel  126  and the second end is coupled to the valve fitting. The first injection conduit  114   a  is mechanically and fluidically coupled to the pressure vessel  126  by the first end  216   a . The first injection conduit  114   a  is mechanically and fluidically coupled to the first valve fitting  104   a  by the second end  218   a . The second injection conduit  114   a  is mechanically and fluidically coupled to the pressure vessel  126  by the first end  216   a . The second injection conduit  114   a  is mechanically and fluidically coupled to the second valve fitting  104   a  by the second end  218   a . The third injection conduit  214   c  is mechanically and fluidically coupled to the pressure vessel  126  by the first end  216   c . The third injection conduit  214   c  is mechanically and fluidically coupled to the third valve fitting (not shown) by the second end  118   c . The fourth injection conduit  114   d  is mechanically and fluidically coupled to the pressure vessel  126  by the first end  216   d . The fourth injection conduit  114   d  is mechanically and fluidically coupled to the fourth valve fitting  2  (not shown) by the first end  216   d.    
     As shown in  FIG. 1 , each injection conduit can include an isolation valve positioned in the respective injection conduit to control the flow of fluid through the respective injection conduit. The isolation valves are operated simultaneously to flow the cleaning fluid  106  from the pressure vessel  126  to the blocked valve fittings. A first isolation valve  120   a  controls the flow of fluid through the first injection conduit  114   a . A second isolation valve  120   b  controls the flow of fluid through the second injection conduit  114   b . Referring to  FIG. 2 , a third isolation valve  220   b  controls the flow of fluid through the third injection conduit  214   c . A fourth isolation valve  220   d  controls the flow of fluid through the fourth injection conduit  214   d . The isolation valves ( 120   a ,  120   b ,  220   c , and  220   d ) can be a ball valve that when in an open position allows flow of the fluid from the pressure vessel  126  to the respective valve fitting  104   a ,  104   b , and the third valve fitting and the fourth valve fitting (not shown) and when in a shut position stops flow of the fluid from the pressure vessel  126  to the respective valve fitting  104   a ,  104   b , and the third valve fitting and the fourth valve fitting (not shown). 
     Each injection conduit can include a pressure gauge fluidically coupled to the injection conduit to sense the pressure of the cleaning fluid  106 . The pressure gauges are positioned in the downstream direction from both the pressure vessel  126  and the isolation valve, toward the valve fitting. The downstream direction is the direction of fluid flow from the pressure vessel  126  toward the valve  102 . For example, a first pressure gauge  122   a  is fluidically coupled to injection conduit  114   a  to sense the pressure of the cleaning fluid  106  in injection conduit  114   a . Similarly, a second pressure gauge  122   b  is fluidically coupled to injection conduit  114   b  to sense the pressure of the cleaning fluid  106  in injection conduit  114   b . Referring to  FIG. 2 , a third pressure gauge  222   c  is fluidically coupled to injection conduit  214   c  to sense the pressure of the cleaning fluid  106  in injection conduit  214   c . Likewise, a fourth pressure gauge  222   d  is fluidically coupled to injection conduit  214   d  to sense the pressure of the cleaning fluid  106  in injection conduit  214   c.    
     A pressure vessel pressure gauge  124  can be fluidically coupled to the pressure vessel  126 . The pressure vessel pressure gauge  124  senses the pressure in the pressure vessel  126 . When the pressure vessel  126  contains cleaning fluid  106 , the pressure vessel pressure gauge  126  senses the pressure of the cleaning fluid  106  in the pressure vessel  126 . 
     The valve fitting unblocking tool  100  can include a controller  224  as shown in  FIG. 2 . In some implementations, the controller  224  is a non-transitory computer-readable medium storing instructions executable by one or more processors to perform operations described herein. In some implementations, the controller includes firmware, software, hardware or combinations of them. The instructions, when executed by the one or more computer processors, cause the one or more computer processors to unblock multiple valve fittings with the valve fitting unblocking tool. The controller  224  is operatively coupled to the various valves described herein. The controller  224  also receives signals representing conditions from the various sensors described herein. 
     The controller  224  is operatively coupled to the input isolation valve  112  to control flow through the input conduit  110 . The controller  224  commands the input isolation valve  112  to open, allowing flow or to close, stopping flow through the input conduit  110 . In the same way, the controller  224  is operative coupled to the first isolation valve  120   a , the second isolation valve  120   b , the third isolation valve  220   c , and the fourth isolation valve  220   d . The controller  224  commands the first isolation valve  120   a  to open, allowing flow or to close, stopping flow through the first injection conduit  114   a . The controller  224  commands the second isolation valve  120   b  to open, allowing flow or to close, stopping flow through the second injection conduit  114   b . The controller  224  commands the third isolation valve  220   c  to open, allowing flow or to close, stopping flow through the third injection conduit  214   c . The controller  224  commands the fourth isolation valve  220   d  to open, allowing flow or to close, stopping flow through the fourth injection conduit  214   d.    
     The controller  224  receives a signal from the pressure vessel pressure gauge  124  representing the pressure vessel  126 . The controller  224  receives a signal from the first pressure gauge  122   a  representing the pressure of the cleaning fluid  106  in injection conduit  114   a . Similarly, the controller  224  receives a signal from the second pressure gauge  122   b  representing the pressure of the cleaning fluid  106  in injection conduit  114   b . Referring to  FIG. 2 , the controller  224  receives a signal from the third pressure gauge  222   c  representing the pressure of the cleaning fluid  106  in injection conduit  214   c . Likewise, the controller  224  receives a signal from the fourth pressure gauge  222   d  representing the pressure of the cleaning fluid  106  in injection conduit  214   c.    
     The controller  224  can control the process of pressurizing the pressure vessel. The pressure vessel pressure gauge  124  senses the pressure vessel pressure. The pressure vessel pressure gauge  124  transmits a signal representing the pressure vessel pressure to the controller  224 . The controller  224  then determines when the pressure vessel pressure is less than or equal to a minimum injection pressure. In response to determining that the pressure vessel pressure is less than or equal to a minimum injection pressure, the controller  224  opens the input pressure isolation valve  112  allowing flow of the pressurized cleaning fluid into the pressure vessel  102 . Alternatively, the manual hand pump  108 , shown in  FIG. 3 , is operated to raise the pressure vessel pressure to the minimum injection pressure. The controller  224  determines that a pressure vessel  102  pressure has reached at least the minimum injection pressure by receiving signals from the pressure vessel pressure gauge  124 . In response to determining that the pressure vessel  102  pressure has reached at least the minimum injection pressure, the controller  224  shuts the input pressure isolation valve  112  to maintain the pressure vessel  102  pressure at the minimum injection pressure. 
     The controller  224  can simultaneously flow the cleaning fluid from the pressure vessel  102  through the first injection conduit  114   a  to the first valve fitting  104   a  and through the second injection conduit  114   b  to the second valve fitting  104   b . The first pressure gauge  122   a  samples the first fluid pressure in the first valve fitting  104   a  and transmits a signal representing the first fluid pressure to the controller  224 . The second pressure gauge  122   b  samples a second fluid pressure in the second valve fitting  104   b  and transmits a signal representing the second fluid pressure to the controller  224 . The controller  224  receives the first injection conduit  114   a  pressure and the second injection  114   b  conduit pressure. The controller  224  determines that the first injection conduit  114   a  pressure is less than the minimum injection pressure. In response to determining that the first injection conduit  114   a  pressure is less than the minimum injection pressure, the controller  224  opens the first injection valve  120   a  positioned in the first injection conduit  114   a . The controller  224  senses when the first injection conduit  114   a  pressure is at least the minimum injection pressure. Responsive to sensing the first injection conduit  114   a  pressure is at least the minimum injection pressure, the controller  224  shuts the first injection valve  120   a . Simultaneously before the controller  224  opens the second injection valve  120   b , the controller  224  receives a second injection conduit  114   b  pressure sensed with the second pressure gauge  122   b . The controller  224  determines that the second injection conduit  114   b  pressure is less than the minimum injection pressure. In response to determining that the second injection conduit  114   b  pressure is less than the minimum injection pressure; the controller  224  opens the second injection valve  120   b  positioned in the second injection conduit  114   b . The controller  224  compares the signal representing the second injection conduit  114   b  pressure to the minimum injection pressure. The controller  224  determines when the second injection conduit  114   b  pressure is at least the minimum injection pressure. Responsive to determining that the second injection conduit  114   b  pressure is at least the minimum injection pressure, the controller  224  shuts the second injection valve  114   b.    
     The controller  224  can determine when the first valve fitting  104   a  and the second valve fitting  104   b  are blocked to fluid flow through the valve  102 . The controller  224  opens the first injection valve  120   a . The cleaning fluid  106  is flowed through the first injection conduit  114   a . The controller  224  receives a signal representing the first injection conduit  114   a  pressure, which is compared to the minimum injection pressure. The controller  224  determines when the first injection conduit  114   a  is at least the minimum injection pressure. The controller  224  shuts the first injection valve. The controller  224  receives signals representing the first injection conduit  114   a  over time. The controller  224  determines the first injection conduit  114   a  pressure rate decrease over a time period. The controller  224  compares the first injection conduit  114   a  pressure rate decrease to a first injection conduit  114   a  pressure rate threshold decrease. The controller  224  determines that the first injection conduit  114   a  is blocked when the first injection conduit  114   a  pressure rate decrease is less than the first injection conduit  114   a  pressure rate threshold decrease. The controller  224  opens the second injection valve  120   b . The cleaning fluid  106  is flowed through the second injection conduit  114   b . The controller  224  receives a signal representing the second injection conduit  114   b  pressure and compares the second injection conduit  114   b  pressure to the minimum injection pressure. When the controller  224  determines that the second injection conduit  114   b  pressure is at least the minimum injection pressure, the controller  224  shuts the second injection valve  120   b . The controller  224  determines a second injection conduit  114   b  pressure rate decrease over the time period. The controller  224  compares the second injection conduit  114   b  pressure rate decrease to a second injection conduit  114   b  pressure rate threshold decrease. The controller  224  determines the second injection conduit  114   b  to be blocked when the second injection conduit  114   b  pressure rate decrease is equal to or less than the second injection conduit  114   b  pressure rate threshold decrease. 
     The controller  224  can determine when the first valve fitting  104   a  and the second valve fitting  104   b  are unblocked to fluid flow through the valve  102 . The controller  224  opens the first injection valve  120   a . The cleaning fluid  106  is flowed through the first injection conduit  114   a . The controller  224  receives a signal from the first pressure gauge  122   a  representing the first injection conduit  114   a  pressure. The controller  224  determines that the first injection conduit  114   a  pressure is at least the minimum injection pressure. The controller  224  shuts the first injection valve  102   a . The controller  224  continues to receive signals representing the first injection conduit pressure. The controller  224  determines a first injection conduit  114   a  pressure rate decrease over the time period. The controller  224  compares the first injection conduit  114   a  pressure rate decrease to a first injection conduit  114   a  pressure rate threshold decrease. The controller  224  determines that the first injection conduit  114   a  is unblocked when the first injection conduit  114   a  pressure rate decrease is greater than the first injection conduit  114   a  pressure rate threshold decrease. The controller  224  opens the second injection valve  120   b . The cleaning fluid  106  is flowed through the second injection conduit  114   b . The controller  224  receives a signal representing the second injection conduit  114   b  pressure and compares the second injection conduit  114   b  pressure to the minimum injection pressure. The controller  224  determines that the second injection conduit  114   b  pressure is at least the minimum injection pressure. The controller  224  shuts the second injection valve. The controller  224  continues to receive the signal representing the second injection conduit  114   b  pressure. The controller  224  determines a second injection conduit  114   b  pressure rate decrease over the time period. The controller  224  compares the second injection conduit  114   b  pressure rate decrease to a second injection conduit  114   b  pressure rate threshold decrease. The controller  224  determines that the second injection conduit  114   b  is unblocked when the second injection conduit  114   b  pressure rate decrease is equal to or greater than the second injection conduit  114   b  pressure rate threshold decrease. 
       FIG. 4  is a flow chart of an example method  400  of unblocking multiple valve fittings with the valve fitting unblocking tool. At  402 , a first injection conduit configured to flow a cleaning fluid is coupling to a first valve fitting. The first valve fitting is blocked to fluid flow through the valve. 
     At  404 , a second injection conduit configured to flow the cleaning fluid is couple to a second valve fitting. The second valve fitting is blocked to fluid flow through the valve. At  406 , the first injection conduit is coupled to a pressure vessel configured to hold the cleaning fluid. The cleaning fluid can be flowed from a cleaning fluid source through an input conduit into the pressure vessel. At  408 , the second injection conduit is coupled to the pressure vessel. At  410 , the pressure vessel holding the cleaning fluid is pressurized. 
     At  412 , responsive to pressurizing the pressure vessel, the cleaning fluid from the pressure vessel is simultaneously flowed through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting. The cleaning fluid from the pressure vessel can be simultaneously flowed through the first injection conduit to the first valve fitting by opening a first injection valve positioned in the first injection conduit. The first injection valve is configured to control cleaning fluid flow through the first injection conduit. Responsive to opening the first injection valve, the cleaning fluid is flowed from the pressure vessel to the first valve fitting. Then, the first injection valve is shut. Responsive to shutting the first injection valve, flow of the cleaning fluid is stopped from the pressure vessel to the first valve fitting. Simultaneously with opening the first injection valve, a second injection valve positioned in the second injection conduit configured to control cleaning fluid flow through the second injection conduit is opened. Responsive to opening the second injection valve, the cleaning fluid from the pressure vessel is flowed to the second valve fitting. Then, the second injection valve is shut. Responsive to shutting the second injection valve, flow of the cleaning fluid from the pressure vessel to the second valve fitting is stopped. 
     Pressurizing the pressure vessel, where the pressurizing vessel includes an input conduit configured to flow the cleaning fluid from a cleaning fluid source into the pressure vessel and a pressure vessel pressure gauge fluidically coupled to the pressure vessel, can include sensing, by the pressure vessel pressure gauge, pressure vessel pressure. Pressurizing the pressure vessel can then include determining that the pressure vessel pressure, by the pressure vessel pressure gauge, is less than or equal to a minimum injection pressure. The minimum injection pressure is a minimum pressure necessary to unblock multiple valve fittings simultaneously. In response to determining that the pressure vessel pressure is less than or equal to a minimum injection pressure, a manual hand pump is coupled to the input conduit. An input pressure isolation valve positioned in input conduit is opened. A manual hand pump coupled to the input conduit is operated to raise the pressure vessel pressure to the minimum injection pressure. It is determined that a pressure vessel pressure has reached at least the minimum injection pressure by the pressure vessel pressure gauge. In response to determining that the pressure vessel pressure has reached at least the minimum injection pressure, the input pressure isolation valve is shut to maintain the pressure vessel pressure at the minimum injection pressure. The manual hand pump is decoupled from the input conduit. 
     Simultaneously flowing the cleaning fluid from the pressure vessel through the first injection conduit to the first valve fitting and through the second injection conduit to the second valve fitting can include where a first pressure gauge is fluidically coupled to the first injection conduit downstream from the first injection valve. Downstream from the first injection valve is away from the pressure vessel. The first pressure gauge is configured to monitor a first fluid pressure in the first valve fitting. A second pressure gauge is fluidically coupled to the second injection conduit downstream from the second injection valve. The second pressure gauge is configured to monitor a second fluid pressure in the second valve fitting. A first injection conduit pressure is sensed with the first pressure gauge. It is determined that the first injection conduit pressure is less than the minimum injection pressure. In response to determining that the first injection conduit pressure is less than the minimum injection pressure; the first injection valve positioned in the first injection conduit is opened. It is sensed that the first injection conduit pressure is at least the minimum injection pressure. Responsive to sensing the first injection conduit pressure is at least the minimum injection pressure, the first injection valve is shut. Simultaneously before opening the second injection valve, a second injection conduit pressure is sensed with the second pressure gauge. It is determined that the second injection conduit pressure is less than the minimum injection pressure. In response to determining that the second injection conduit pressure is less than the minimum injection pressure; the second injection valve positioned in the second injection conduit is opened. It is sensed that the second injection conduit pressure is at least the minimum injection pressure. Responsive to sensing the second injection conduit pressure is at least the minimum injection pressure, the second injection valve is shut. 
     The method can further include determining that the first valve fitting and the second valve fitting are blocked to fluid flow through the valve. The first injection valve is opened. The cleaning fluid is flowed through the first injection conduit. The first injection conduit pressure is sensed to be at least the minimum injection pressure. The first injection valve is shut. A first injection conduit pressure rate decrease over a time period is sensed. The first injection conduit pressure rate decrease is compared to a first injection conduit pressure rate threshold decrease. It is determined that the first injection conduit is blocked when the first injection conduit pressure rate decrease is less than the first injection conduit pressure rate threshold decrease. The second injection valve is opened. The cleaning fluid is flowed through the second injection conduit. The second injection conduit pressure is sensed to be at least the minimum injection pressure. The second injection valve is shut. A second injection conduit pressure rate decrease over the time period is sensed. The second injection conduit pressure rate decrease is compared to a second injection conduit pressure rate threshold decrease. The second injection conduit is determined to be blocked when the second injection conduit pressure rate decrease is equal to or less than the second injection conduit pressure rate threshold decrease. 
     The method can further include determining the first valve fitting and the second valve fitting are unblocked to fluid flow through the valve. The first injection valve is opened. The cleaning fluid is flowed through the first injection conduit. The first injection conduit pressure is sensed to be at least the minimum injection pressure. The first injection valve is shut. A first injection conduit pressure rate decrease over the time period is sensed. The first injection conduit pressure rate decrease is compared to a first injection conduit pressure rate threshold decrease. The first injection conduit is determined to be unblocked when the first injection conduit pressure rate decrease is greater than the first injection conduit pressure rate threshold decrease. The second injection valve is opened. The cleaning fluid is flowed through the second injection conduit. The second injection conduit pressure is sensed to be at least the minimum injection pressure. The second injection valve is shut. A second injection conduit pressure rate decrease over the time period is sensed. The second injection conduit pressure rate decrease is compared to a second injection conduit pressure rate threshold decrease. The second injection conduit is determined to be unblocked when the second injection conduit pressure rate decrease is equal to or greater than the second injection conduit pressure rate threshold decrease. 
     At  414 , responsive to flowing the cleaning fluid to the valve fitting, the first valve fitting is unblocked and responsive to flowing the cleaning fluid to the valve fitting, the second valve fitting is unblocked. A first injection conduit second end can be decoupled from the first valve fitting and a second injection conduit second end can be decoupled from the second valve fitting. 
     Although the present implementations have been described in detail, it should be understood that various changes, substitutions, and alterations can be made hereupon without departing from the principle and scope of the disclosure. Accordingly, the scope of the present disclosure should be determined by the following claims and their appropriate legal equivalents.