Patent Publication Number: US-11028958-B2

Title: Automated pig launching system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation of U.S. patent application Ser. No. 14/963,751, filed 9 Dec. 2015, now U.S. Pat. No. 9,976,686, which is a non-provisional of U.S. Patent Application Ser. No. 62/090,057, filed 10 Dec. 2014, both of which are incorporated herein by reference in their entireties and to which priority is claimed. 
    
    
     FIELD OF THE DISCLOSURE 
     This subject matter of the present disclosure relates to devices and methods for launching pipeline pigs. More specifically, the disclosed subject matter relates to a system and methods for staging multiple pigs of any type and launching them individually with a fully-automated, semi-automated, or manually-operated pig launch system that can be horizontally oriented. 
     BACKGROUND OF THE DISCLOSURE 
     Pigging systems are installed on pipeline systems for the purpose of inserting a pipeline pig without interruption of the pipeline flow. Pipeline pigs are typically sized to the nominal pipeline diameter and configured of different designs and materials to serve the purpose of cleaning, liquid removal, drying, batching, chemical treatment, or inspection. Traditional pigging systems (sometimes known as launchers and receivers) have been utilized for decades to insert and retrieve pipeline pigs without interrupting the product flow. The launcher is installed upstream in the traditional pigging system and the receiver unit is installed downstream of the section of the pipeline to be pigged. 
       FIG. 1A  illustrates a pig launcher  10  according to the prior art, and  FIG. 1B  illustrates a pig receiver  20  according to the prior art. Briefly, the launcher  10  has an oversized barrel section  11  connected by an eccentric reducer  12  to a nominal line section  13 . A closure  14  on the barrel section  11  provides access to its interior for inserting a pig (not shown). The line section  13  has a flange  16  for connecting to a line pipe of a piping system. The barrel section  11  includes a blow-down connection  18 A, a kicker connection  18 B, and a drain connection  18 C. The line section  13  includes a pig signaler  15  and a vent  17 . 
     The receiver  20  is similar and has a nominal line section  23  connected by a concentric reducer  22  to an oversized barrel section  21 . A closure  26  on the barrel section  21  provides access to its interior for removing pigs (not shown). The line section  23  has a flange  24  for connecting to a line pipe of the piping system. The barrel section  21  includes a blow-down connection  28 A, a bypass connection  28 B, and a drain connection  28 C. The line section  23  includes a pig signaler  25  and a vent  27 . 
     These units  10 ,  20  are isolated from the mainline with isolation valves (not shown) to allow the pressure to be released and the product drained or vented so that pipeline pigs can be inserted or retrieved from the pipeline system with no pressure or product in the launcher  10  and receiver  20 . Such traditional units  10 ,  20  of the pigging system as shown in  FIGS. 1A-1B  are manually operated to launch and receive a single pipeline pig for each pigging operation. 
     Other pigging systems in the art have an automated pig launcher that can provide improved pipeline flow efficiency, cost savings, and safety by not requiring each pig to be loaded individually. To date, automated pig launchers use a vertical or angled design orientation where the pipeline pigs are gravity fed to the downstream launch mechanism. In particular, the existing launch mechanism has two pins that are retracted by means of hydraulics or pneumatics allowing the pipeline pig to be launched by gravity. Additionally, current automated pig launchers are designed for a specific type of pig and product type. 
     Because current automated pigging systems are gravity fed, the systems need to be elevated at an installation. This requires the installation to have a platform to provide access to the system components and requires lifting equipment to be used for the operation of the unit. Additionally, because current automated pigging systems use hydraulics or pneumatics to actuate launch mechanism, the existing system requires supply gas to drive the hydraulics, which complicates the installation and its operation. In fact, the controller for these current automated pigging systems can be complex, making them harder to operate and maintain. 
     The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above. 
     SUMMARY OF THE DISCLOSURE 
     A method and system stages multiple pigs and individually launches each pig in a fully-automated, semi-automated, or manually operated manner. The system has a launcher oriented in a horizontal position with a flow-through barrel and a launch mechanism. In general, the launch mechanism can be operated by a programmable logic controller, a user-operated switch, or manual operation. 
     In one embodiment, the launch mechanism can use a geared feed screw system that moves a paddle along the internal length of the oversized launch barrel to advance the pigs staged in the barrel. The staged pigs are engaged with the paddle of the geared feed screw launch mechanism, and one of the pipeline pigs is pushed into a reducer transitioning the larger diameter barrel to a pipeline section of the launcher. Differential pressure is created when the pig seals at least partially in the area of the reducer of the launcher located downstream of a flow-through nozzle. The process flow behind the advanced pig then allows the pig to be launched into the downstream piping. The gears on the drive mechanism can be manually operated, operated on-demand, or programed with an independent controller that allows pig launches to be made at a specific time or time interval. 
     The launcher does not require gravity to feed the pigs. Therefore, the launcher can be positioned horizontal at a site. This has the benefits of eliminating the need for an elevated platform and associated structures, lifting equipment, and the like. In addition, the horizontal arrangement reduces costs and the complexity of ancillary piping. 
     In general, the launch mechanism includes a guide and an actuator. The mechanism can use a motor, a feed screw, a cable, a cylinder, or other drive member used in conjunction with a paddle, a cradle, a tray, or the like. Pigs may also be positioned for launch using a conveyor belt type mechanism. 
     In the system, the launcher has a pipeline connection flange through which process flow normally flows. Pigs are positioned for launch using the controlled feed of the launch mechanism, which is independent of the particular pig. The launch and sequencing are not dependent on specific pig dimensions and can be programmed, thereby allowing the use of pigs of varying purpose, dimensions, and manufacture. Pigs for differing purpose and physical size/configuration may be loaded in the same batch. Finally, the flow-through pipeline connection on the launcher obviates the need for actuating pipeline valves. This reduces cost and complexity of unit. 
     In operation, process flow is initially diverted from the launcher, and any residual fluid is drained from the launcher. The closure door of the launcher is opened to provide access to the launcher&#39;s chamber. A batch of pigs is loaded in the launcher, which is then closed and filled with process flow. 
     Pig information and launch requirements are entered into the controller, and flow is redirected through the launcher. At the programed time, a pig is fed into the process flow by the launch mechanism and launched. The pig moves through the pipeline, accomplishes an intended task, and ultimately enters a receiver. At the programed time, the next pig in sequence is moved into the process flow and launched to move through pipeline and then enter the receiver. The sequence can be repeated until an entire batch of pigs is launched and received. A typical batch quantity can be about seven pigs. 
     The foregoing summary is not intended to summarize each potential embodiment or every aspect of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  illustrates a pig launcher according to the prior art. 
         FIG. 1B  illustrates a pig receiver according to the prior art. 
         FIG. 2A  illustrates a perspective view of a pig launcher according to the present disclosure with flow-through and kicker piping. 
         FIG. 2B  illustrates a perspective view of the disclosed pig launcher isolated from the additional piping. 
         FIG. 2C  illustrates a perspective view of the disclosed pig launcher with a cutaway showing internal components thereof. 
         FIG. 3A  illustrates a perspective view of a pig receiver according to the present disclosure with flow-through and flow-exit piping. 
         FIG. 3B  illustrates a perspective view of the disclosed pig receiver without the additional piping. 
         FIGS. 4A-4C  illustrate details of nozzles disposed on the disclosed pig launcher. 
         FIGS. 5A-5D  illustrate embodiments of launch mechanisms for guiding and mechanically feeding pigs in the disclosed pig launcher. 
         FIG. 6A  illustrates a gear box for the disclosed pig launcher. 
         FIG. 6B  illustrates a worm gear feed screw for the disclosed pig receiver. 
         FIG. 6C  illustrates a support bearing for the disclosed pig launcher. 
         FIG. 7  illustrates a cross-sectional view of a high pressure seal for the worm gear of the disclosed pig launcher. 
         FIG. 8  illustrates a launch paddle for the disclosed pig launcher. 
         FIGS. 9A-9B  illustrate perspective and end views of a launch tray for the disclosed pig launcher. 
         FIG. 10A-10D  show example user interface screens for a controller of the disclosed pig launcher. 
     
    
    
     DETAILED DESCRIPTION OF THE DISCLOSURE 
     A. Pigging System 
     A pigging system of the present disclosure includes a pig launcher  100  ( FIGS. 2A-2C ) and a pig receiver  200  ( FIGS. 3A-3B ) for a pipeline. As will be appreciated, a typical pipeline can conduct any type of process flow, product, or non-solid material, such as a gas, a liquid, or a colloidal suspension capable of being transported through the pipeline. Examples of products that are transported through a pipeline may include: natural gas, propane, crude oil, water, and petroleum condensate. 
     The pig launcher  100  is assembled on the pipeline from where pigs P are to be launched to perform an intended task related to pigging. The launcher  100  is typically placed at the start of a pipeline section to be pigged. For its part, the pig receiver  200  is assembled on the pipeline to where pigs P are received after performing their intended tasks related to pigging. The receiver  200  is typically placed at the end of a pipeline section to be pigged. 
     As is known, a pig P is a device that is inserted into the pipeline to perform a specific task. In various embodiments, pigs P may be utilized to perform tasks that may include: cleaning, liquid removal, drying, batching, chemical treatment, and inspection. A pig may be unidirectional or bidirectional. 
     In  FIG. 2A , the pig launcher  100  is shown with additional piping  30 , while the pig launcher  100  is shown in an isolated view in  FIG. 2B  and is shown with internal components visible in  FIG. 2C . The pig launcher  100  is used for staging multiple pigs P and launching them individually into a pipeline (not shown) via an introductory pipe or line L. As discussed below, operation of the pig launcher  100  can be fully-automated, semi-automated, or manual, as desired for a particular implementation. 
     The pig launcher  100  includes a housing  102  defining a chamber  105  and having an inlet  104 A and an outlet  104 B. The inlet  104 A receives one or more pigs P into the chamber  105  and is sealable, for example, using a closure  111 , such as a door. The outlet  104 B connects in sealed communication with the process flow in the line L of the piping system  30 . The outlet  104 B passes the one or more pigs P out of the chamber  105  to the process flow. 
     Internally as best shown in  FIG. 2C , a guide  106  is disposed in the chamber  105  and guides the one or more pigs P in the chamber  105 . Additionally, an actuator  108  mechanically feeds the one or more pigs P guided by the guide  106  to the outlet  104 B. A portion of the chamber  105  is in communication with the process flow of the piping system  30  via a number of connections and valves discussed below. 
     In  FIG. 3A , the pig receiver  200  is shown with additional piping  40  for flow-through and flow-exit, while the pig receiver  200  is shown in an isolated view in  FIG. 3B . The pig receiver  200  includes a nominal line pipe section  230 , a concentric reducer  220 , and an oversized barrel section  210 . The receiver&#39;s barrel section  210  is of extended length to accommodate multiple pigs received from the line L to which the receiver  200  is coupled with an isolation valve  42 . 
     Looking more closely now at the pig launcher  100  of  FIGS. 2A-2C , the housing  102  has an oversized barrel section  110 , an eccentric reducer  120 , and a nominal line section  130 . A launching mechanism  140  incorporated into the housing  102  includes the guide  106  and the actuator  108 . 
     The barrel section  110  is elongated to stage multiple pigs P in its interior chamber  115 . During operation, the launching mechanism  140  launches the pigs P individually into the process flow of the line L to which the launcher  100  is coupled with an isolation valve  32  at the outlet  104 B of the launcher  100 . 
     The pig launcher  100  has a horizontally oriented design that connects by means of a flange connection  131  at the outlet  104 B to the isolation valve  32 . The barrel section  110  is oversized in its diameter, which allows for flow to bypass the pigs and relieves any motive force. For example, the diameter of the barrel section  110  may be twice the diameter of the nominal pipe section  130 . The nominal pipe section  130  may be sized to be twice as long as the nominal pipe diameter. The length of the barrel section  110  may be about 14× the line pipe diameter. The distal end of the barrel section  110  either has a flanged connection at the inlet  104 A or is prepared with a weld bevel to install a quick opening closure  111  or other access fitting to allow access for loading pigs P into the barrel section  110 . 
     As noted above, portion of the chamber  105  is in communication with the process flow of the piping system  30  via a number of connections and valves. In particular, a blow-down nozzle or port  112  (shown in detail in  FIG. 4A ) is disposed toward the top of the housing  110  and communicates with the chamber  115  near the inlet  104 A. The blow-down nozzle  112  is used for depressurizing the chamber  115 . 
     A flow-through nozzle or port  114  (shown in detail in  FIG. 4B ) is located on the barrel section  110  and is oriented horizontally, one nominal pipe diameter upstream of the distal end of the eccentric reducer  120 . The area of the housing  102  upstream from the flow-through nozzle  114  to the outlet  104 B forms a flow-through section where process flow continuously flows as part of the launcher&#39;s operation. 
     Finally, a kicker nozzle or port  116  and a drain nozzle or port  118  (both shown in detail in  FIG. 4C ) communicate with the chamber  115  near the inlet  104 A. The kicker nozzle  116  is disposed toward the side of the housing  110  and is used for providing a kick of fluid into the chamber  115  when launching a specialized pig that is not launched automatically. The drain nozzle  118  comes off the bottom of the housing  102  and is used for draining the chamber  115  of fluid. 
     In the present embodiment, the integrated components of the launch mechanism  140  include a worm gear feed screw  150 , one or more bearing assemblies  152 A-B, a launch paddle  156 , a gear box  154 , a motor  160 , and a controller  170 . Some details of the feed screw  150 , the paddles  156 , etc. are shown in  FIG. 2C . Details of the launch mechanism  140  are discussed further below. 
     In one advantage, the pig launcher  100  is horizontally oriented, which eliminates the need for elevated platforms required to insert the pigs P. Additionally, the oversized barrel section  110  and the pipe section  130  of the launcher  100  (as well as the receiver) are longer for the purpose of launching and receiving multiple pigs P. In particular, the tubular barrel section  110  is elongated to accommodate a series of pipeline pigs P loaded end-to-end to stage their introduction into the pipeline system. Moreover, the disclosed launching mechanism  140  can be adapted to accommodate a various number of pigs P and is not restricted to a specific pig type to be used, launch interval, or pipeline product. 
     B. Launch Mechanisms 
     The launch mechanism  140  introduces (launches) the pipeline pigs P one at a time into the line L of the pipeline system. As noted above, the launch mechanism  140  in  FIGS. 2A-2C  includes the worm gear feed screw  150  installed inside the elongated barrel section  110 . This is represented again more schematically in a transparent view of the launcher  100  in  FIG. 5A . 
     The feed screw  150  is installed at the 12 o&#39;clock position in the barrel section  110  and extends the entire length of the elongated section  110 . The feed screw  150  (an example of which is shown in  FIG. 6B ) can be composed of stainless steel. At its distal end toward the inlet  104 A of the barrel section  110 , the worm gear feed screw  150  is attached to the barrel section  110  by means of a bearing assembly  152 A, which attaches the feed screw  150  to the internal wall of the oversized barrel section  110 . 
     The bearing assembly  152 A can be a pillow block, such as shown in  FIG. 6C , which is connected to the barrel section  110  to support the distal end of the worm gear feed screw  150 . The feed screw  150  extends to the proximal end of the over-sized barrel section  110  at the 12 o&#39;clock position and can connect to a secondary bearing assembly  152 B. Then at the eccentric reducer  120 , the feed screw  150  exits the housing  102  with a high pressure seal  158 , such as shown in  FIG. 7 . 
     The feed screw  150  extends beyond the high pressure seal  158  and connects to an output shaft  155 B of a gear box  154  ( FIG. 6A ). An input gear box shaft  155 A ( FIG. 6A ) can be utilized to install the motor  160  for fully-automated or semi-automated embodiments. Alternatively, the gear box shaft  155 A can be hand-operated for manual capabilities. 
     Either way, the worm gear feed screw  150  can be rotated circumferentially within the barrel section  110 . Rotation of the feed screw  150  then moves the launch paddle  156  along the feed screw&#39;s length so pigs P can be loaded toward the launch reducer  120 . Being internal to the barrel section  110 , the paddle  156  is movably attached to the feed screw  150  by a threaded coupling  157 A ( FIG. 8 ) and travels from the distal end to the proximal end of the barrel section  110  to push the pipeline pigs P into the launch reducer  120 . 
     The motor  160  can be an electric motor, although other drives can be used. For example, a hydraulic motor can be used, but may require a pneumatic supply gas to operate/actuate the launch mechanism  140 . Most pneumatic supply gases are provided by natural gas from the pipeline so a pump can drive the hydraulics. There may be methane emissions as the pneumatic pump strokes so using an electric motor can eliminate such methane emissions. 
     For automated operation, the motor  160  can be connected to a controller  170  having a programmable logic controller and a display. The controller  170  is operable to actuate the motor  160  based on pre-programmed time intervals, local operation, remote operation, or other automated control scheme. Further details of any automated operation are discussed below. 
     As noted above, the gear box  154  and the motor  160  are preferably disposed external to the barrel section  110 . Therefore, the connection of the gear box  154  to the worm gear feed screw  150  passing through the housing&#39;s wall uses the high-pressure seal  158 , as shown in  FIG. 7 . The high pressure seal  158  seals the extended gear drive mechanism from the internal line pressure so that it can be operated external to the pressurized side of the launch mechanism  140 . 
     In general, the seal  158  can be created in several ways, including but not limited to one or more of: an O-ring type seal being of either conventional or one of the many existing varieties of cross-section, a lip-type rotary seal, or a conventional stuffing box arrangement (e.g., a gland-type of stuffing box seal). For the gland-type seal, a loosely braided or otherwise deformable sealing material is layered in a cavity around the shaft of the feed screw  158  passing through the barrel wall. A packing gland/nut, which generates a large force along the axis of the shaft, is used to compress the seal material within the cavity causing it to exert pressure against the cavity wall and shaft surface. Sufficient force is applied so that the compression forces of the packing material exceed the pressure being contained and leakage is prevented. As will be appreciated, the sealing and packing area of the seal  158  can be incrementally increased based on the specified pipeline pressures and other requirements of an implementation. 
     In addition to the feed screw  150 , the paddle  156 , and other features for the launch mechanism  140  to guide and mechanically feed the pigs P horizontally, other mechanisms can be used. For example, the launch mechanism  140  can use a motor, a feed screw, a cable, a cylinder, or other drive member used in conjunction with a paddle, a cradle, a tray, or the like. Pigs may also be positioned for launch using a conveyor belt type mechanism. 
     Although a rotatable feed screw  150  and paddle  156  have been disclosed above for the launch mechanism  140 , other actuators and guides can be used to move the staged pigs P along the length of the barrel section  110 . In this regard, hydraulic or pneumatic cylinders can have arms that move inside the barrel section  110  and push and/or pull the paddle  156  inside the barrel section  110 . The paddle  156  may be supported on rails or the like. Alternatively, a rack and pinion system could be used. As will be appreciated with the benefit of the present disclosure, these and other mechanisms can be used to move the pigs in the launcher  140 . 
       FIG. 5B  shows an example of a launch mechanism  140  having a motor  160  that rotates a drive belt  151  with a gear  161 . Forward and reverse rotation of the gear  161  can move a paddle  156  on the belt  151  back and forth in the chamber  115  of the barrel section  110 . In this way, pigs P can be individually fed with the belt  151  to the area adjacent the feed-through nozzle  114  upstream of the line section  130  of the launcher  100 . 
       FIG. 5C  shows another example of a launch mechanism  140  having a motor  160  that moves a linear actuator  153 . For example, the motor  160  can be hydraulic, and the linear actuator  153  can be a piston or the like. Extension and retraction of the linear actuator  153  can move a paddle  156  back and forth in the chamber  115  of the barrel section  110 . In this way, pigs P can be individually fed with the linear actuator  153  to the area adjacent the feed-through nozzle  114  upstream of the line section  130  of the launcher  100 . 
       FIG. 5D  shows yet another example of a launch mechanism  140  having a motor  160  moves a conveyor belt  155  with a gear  165 . Forward and reverse rotation of the gear  165  can move the conveyor belt  151  back and forth in the chamber  115  of the barrel section  110 . In this way, pigs P can be individually fed with the belt  155  to the area adjacent the feed-through nozzle  114  upstream of the line section  130  of the launcher  100 . 
     As the various launch mechanisms  140  disclosed in  FIGS. 5A-5D  will show, a number of different mechanisms that guide and actuate can move pigs P in the barrel section  110  and can be used with the launcher  100 . Accordingly, these and other alternatives of the disclosed launch mechanisms  140  can be used. Moreover, discussion herein may refer to the components of the launch mechanism  140  in  FIG. 5A , but not necessarily others as in  FIGS. 5B-5D . However, it will be appreciated with the benefit of the present disclosure that features discussed herein can be readily adapted to the various disclosed launch mechanisms. 
     C. Launch Tray 
     Most commonly, but not always, a launch tray  180  as shown in  FIGS. 9A-9B  can install into the bottom of the barrel section  110  to stage multiple pipeline pigs P into the launch mechanism  140 . The launch tray  180  can be removed from the barrel section  110 , loaded with a specific number of pigs P, and reinserted into the barrel section  110  to stage the pigs P for launching. In general, the launch tray  180  is a channel in which pigs P are horizontally placed for staging into the launching mechanism  140 . 
     The launch tray  180  includes sidewalls  182  and a curved base  184  for resting in the barrel section  110 . Guide rails  183  are provided on the sidewalls  182  to help hold the pigs P on the base  184 . Additionally, the guide rails  183  can allow guide arms, such as arms  157   b  on the paddle  156  in  FIG. 8 , to ride and guide movement of the paddle  156  along the launch tray  180  as the paddle  156  is moved inside the barrel section  110 . Friction guides  185  can also be installed on the sidewalls  182  of the tray  180  to produce friction on the moving pigs P. This controlled friction from the guides  185 , the base  184 , etc. on the tray  180  can be used to ensure that only one pig P at the end of the tray  180  is fed into the reducer  180  at a time during a launch sequence. 
     Depending on the pigs P used, the launch tray  180  may not be needed, or a particular launch tray  180  may have adjustable components (e.g., sidewalls  182 , guide rails  183 , etc.) that allow it to accommodate different types of pigs. Alternatively, a different launch tray may be used to accommodate different types of pigs. For example, the launch tray  180  need not be an open-type of bed with sidewalls  182  and base  184 . Instead, the launch tray  180  can be an elongated canister for staging the pigs P and can be composed of a perforated aluminum tube or the like having a slot to accommodate the paddle&#39;s passage. 
     D. Controller/Automation 
     As noted above, an external drive mechanism (e.g., gear box  154 , motor  160 , etc.) operates the launch mechanism  140 . The external drive mechanism can be operated manually, semi-automatically, and automatically. In particular, to operate the launch mechanism  140  manually, operators can manually operate the shaft  155 A of the worm gear drive mechanism with a wrench or a drill motor to actuate the pig paddle  156  towards the reducer  120  to launch a pipeline pig P. In this manual operation, the travel distance of paddle  156  is controlled by the number of turns made to the extended gear shaft  155 A. 
     The launch mechanism  140  can also be operated automatically or semi-automatically. As noted previously, the gear shaft  155 A of the drive mechanism  154  can be operated with a motor  160 , such as an explosion-proof electric motor, to actuate the launch paddle  156  towards the reducer  120  to launch a pipeline pig P. The electric motor  160  can be controlled semi-automatically by an operator with an ON/OFF switch to the desired paddle travel distance. Alternatively, the electric motor  160  can be controlled automatically by programmed logic of the controller  170 . 
     In general, the controller  170  can include a control panel, which can display control screens to program the specific launch interval, launch time, remote actuation, or other operation. The controller  170  is programmed in accordance to the pig type and pig length. In turn, the controller  170  controls the electric motor  160  and the travel distance of the paddle  156  to launch pipeline pigs P. In short, the controller  170  controls the actuation of the launching mechanism  140  for the fully-automated operation. 
     The controller  170  can have an Ethernet or other connection to remotely access the launch mechanism  140  to monitor performance and/or control the launching of a pipeline pig P. The controller  170  also operates as a terminal to monitor pig passages with a signal receiver from a remote pig signaler, and the controller  170  can monitor the amperage during operation of the launcher  100 , among other monitoring operations. 
     The controller  170  may have connections to (or may use any signals from) flow sensors, pig detectors, or other sensing equipment, and the controller  170  can use such signals to control operation of the launcher  100  automatically. For example, the controller  170  can have a number of auxiliary terminals to provide various functions. In particular, the controller  170  can use a pig signaler  137  located on the nominal pipe section  130  immediately downstream of the eccentric reducer  120 . Signals from the signaler  137  can be used by the controller  170  to validate passage of a pig P whenever the launch mechanism  140  has launched a pig P. 
     The controller  170  may also receive a signal from a signaler located downstream of the mainline isolation valve  32  attached to the pig launcher  100  to validate a pig&#39;s passage, and the controller  170  can use that information to determine that the pig is traversing the pipeline L whenever the launch mechanism  170  has launched a pig P. Additionally, the controller  170  can have a terminal connection to a remotely-operated valve that can act as a fail-safe mechanism. In this sense, the controller  170  can automatically shut-off the pig launcher  100  any time that the mainline isolation valve  32  is closed. 
       FIGS. 10A-10D  illustrate example user interface screens  176   a - d  for programming the controller  170  to operate the disclosed launcher  100 . In  FIG. 10A , the first screen  176   a  shows an example of how an operator can set the number of pigs P to be loaded in the launcher  100 . The length of each pig P can be input, should different length pigs P be used. The timing of the launch for the various pigs P can also be input. The number of pigs P in the barrel section  100  and the position of the paddle  156  inside the section  100  can be known and displayed. Manual mode or over-ride controls may also allow operators to manually move the paddle  156  back and forth. 
     The screen  176   b  in  FIG. 10B  shows some input and control information of the controller  170 . The screen  176   c  in  FIG. 10C  shows how an operator can set different launch intervals for the various pigs P and can set when a first launch is to take place. Finally, the screen  176   d  in  FIG. 10D  shows how the length of a given pig P can be input so the controller  170  can track the position of the pig P in the section  110  and the needed movement of the paddle  156  and the like to launch the pig P. 
     As these user interface screens  176   a - d  will show, the controller  170  of the present disclosure can be programmed in a number of ways and with a number of inputs to control operation of the disclosed launcher  100 . As will be appreciated, these and other inputs and controls can be used. 
     E. Operation 
     In operation, the pig launcher  100  can stage multiple pipeline pigs P from the horizontally-oriented pig launch mechanism  140  and can launch a single pig P from the housing  102  in liquid and gas service from its horizontal orientation. The launch mechanism  140  can be fully-automated, semi-automated, or manually-operated and can launch various types of pigs P on a controlled basis. 
     For fully-automated operation, operators can program the controller  170  to operate the electric gear-operated pig launch mechanism  140  based on pipeline pig length and other factors. In this way, the launcher  140  can launch a single pig P and can stage multiple pipeline pigs P even in low flow conditions. 
     With an understanding of the pig launcher  100  and its components, particular discussion is provided on the operation of the launcher  100  to launch pigs for a pigging operation. Initially, all valves must be in the closed position to initiate the operation of the pig launching mechanism  140 . For example, the closed valves on the housing  102  as in  FIG. 2A  include the mainline isolation valve  32 , the flow-through valve  34  for the flow-through nozzle  114 , the blow-down valve  38  for the blow-down nozzle  112 , the kicker valve  36  for the kicker nozzle  116 , and the drain valve (not shown) for the drain nozzle  116 . The pig launching sequence is initiated by opening the access door  111  located at the input  104 A of the over-sized barrel section  110  after the pressure has been relieved from the entire launch system by opening the system&#39;s blow-down nozzle  112  located at the 12 o&#39;clock orientation. 
     The launch paddle  156  is removed from the feed screw  150 , and the launch tray  180 , if used, is removed at the inlet  104 A from the over-sized barrel section  110  in the distal direction. Pigs P are loaded into the launch tray  180 , and the launch tray  180  is reinserted into the over-sized barrel section  110 . If a launch tray  180  is not used, the pigs P are loaded directly into the over-sized barrel section  110 . 
     The access door  111  is closed, then the valve  38  for the blow-down nozzle  112  is closed to allow for pressurization of the launcher  100 . The flow-through valve  34  is slowly opened to equalize the pressure between the launcher  100  and the line L. The flow-through nozzle valve  34  will remain in the “open” position throughout the duration of the operation of the launch mechanism  140 . Once the pressure has equalized in the automated launcher  100 , the mainline valve  32  is opened. 
     In preparation of the operation, the controller  170  can be programmed for fully-automated operation, as shown by the example screens  176  in  FIGS. 10A-10D . The pig length, number of pigs, schedule for the first pig launch, and the interval for subsequent launches are entered into the controller  170 . The controller  170  will actuate a pig of a specific length at the scheduled time based on the travel distance of the launch paddle  156  in the proximal direction into the eccentric reducer  120 . 
     Alternatively, semi-automated launch operations can be performed by activating the electric motor  160  for a predetermined period based on the measured pig length and travel distance of the launch paddle  156  in the proximal direction into the eccentric reducer  120 . In this semi-automated operation, the launcher  100  does not necessarily need to be equipped with a controller  170  since the semi-automated function can be operated with the motor  160  to actuate the mechanical launch mechanism  140 . 
     As noted previously, manual operation can also be performed by turning the gear box shaft  155 A the appropriate revolutions to actuate the launch paddle  156  the measured length of one pig P in the proximal direction to the eccentric reducer  120 . For a manually operated implementation, the launcher  100  does not require a motor  160  or a controller  170  since the launcher  100  is hand-operated to actuate the mechanical launch mechanism  140 . 
     The foregoing description of preferred and other embodiments is not intended to limit or restrict the scope or applicability of the inventive concepts conceived of by the Applicants. It will be appreciated with the benefit of the present disclosure that features described above in accordance with any embodiment or aspect of the disclosed subject matter can be utilized, either alone or in combination, with any other described feature, in any other embodiment or aspect of the disclosed subject matter. 
     Although the pig launcher  100  has been described as being used horizontally at an installation, this is not strictly necessary since the launcher  100  can be used in other orientations and can even be angled. In fact, it is contemplated that the launcher  100  can be oriented vertically with the paddle  156  moving the pigs P upward to the pipeline or downward to the pipeline. If fed upward, the angled or vertical launcher  100  may not require much alteration to accommodate individually introducing the pigs P to the pipeline. However, if fed downward, a hydraulic mechanism (pin or the like) may be needed to stop the advance of the pigs P in the angled or vertical launcher  100 . 
     In exchange for disclosing the inventive concepts contained herein, the Applicants desire all patent rights afforded by the appended claims. Therefore, it is intended that the appended claims include all modifications and alterations to the full extent that they come within the scope of the following claims or the equivalents thereof.