Patent Publication Number: US-2023142564-A1

Title: Apparatus for couplant management

Description:
CLAIM FOR PRIORITY 
     The present application claims priority to U.S. Provisional Application Ser. No.  63 / 003 ,379 entitled “Apparatus For Couplant Management” having attorney docket number 6409.097PRV to Faucher et al. filed on Apr. 1, 2020, the contents of which are incorporated herein in their entirety. 
    
    
     TECHNICAL FIELD 
     This document pertains generally, but not by way of limitation, to Nondestructive Testing (NDT) of structural components and systems. In particular, implementations of the present disclosure provide a compact apparatus that manages couplant used therein during NDT of structural components and systems. 
     BACKGROUND 
     NDT can be used to locate and characterize material features on or within an article. Such features can indicate a presence of flaws such as cracks or voids, or material characteristics such as porous regions or interfaces between differing materials. For example, NDT can be used in the aerospace field to perform non-destructive inspection of components such as airfoils or turbine components, as illustrative examples. Generally, NDT is performed in a manner that does not damage the article during or after testing. Examples of NDT can include ultrasonic scanning where a couplant facilitates coupling of acoustic energy from a transducer array to an article under test. For example, water or a gel can be used as a couplant where the couplant serves an acoustic matching medium between the article and the transducer array, avoiding unwanted scattering or reflection that might occur if dissimilar materials (e.g., air) were present between the transducer array and the article. When water is used as the couplant during testing, an immersion bath can be used or, in instances where an immersion bath is not viable, a device can be used that dispenses the water over the article being tested and an area surrounding the article. Such an approach can be wasteful if the water merely drains away from the inspection interface. In instances where an immersion bath is not viable, air bubbles may be present within or near an inspection interface between a probe and the article under test during NDT. 
     SUMMARY 
     What is needed is an apparatus that suppresses or inhibits air bubbles from an inspection area of an article during NDT of the article. The apparatus can economize expenditure of couplant, such as using a recirculation approach, and may be adaptable for surfaces having various contours. 
     Examples of the present disclosure can provide a couplant feeding circuit plate that can be used with a device that inspects an article using NDT. Couplant is routed to an area of the article being inspected and, at least in part, removed from the area being inspected via the couplant feeding circuit plate. In an implementation, the couplant feeding circuit plate can include a housing the extends circumferentially around a couplant cavity. In an implementation, the couplant cavity defined by the wall and a membrane. Moreover, in an implementation, the couplant feeding circuit plate can include a couplant port and a vacuum port. The couplant port can route couplant to the couplant cavity while the vacuum port can route at least a portion of the couplant from the couplant cavity. 
     In an implementation, the couplant feeding circuit plate can include a first set of walls extending from a bottom surface of the couplant feeding circuit plate and a second set of walls extending from the bottom surface of the couplant feeding circuit plate and between the first set of walls. Moreover, the couplant feeding circuit plate can include a membrane that extends between the first set of walls and the second set of walls where the first set of walls, the second set of walls, and the membrane form a couplant cavity. In an implementation, the couplant feeding circuit plate can include a couplant port and a vacuum port disposed in one of the first set of walls and the second set of walls. In an implementation, the couplant port allows pushing of a couplant to the couplant cavity while the vacuum port allows removal of at least a portion of the couplant from the couplant cavity. In an implementation, in addition to pulling the couplant, the vacuum port can pull air bubbles that may be present in the couplant cavity. 
     In an implementation, the couplant feeding circuit plate can be configured to couple with different wedges of different NDT apparatuses at a top surface of the couplant feeding circuit plate opposite the bottom surface. Moreover, in an implementation, the couplant feeding circuit plate can include a first side and a second side opposite the first side, where the couplant port and the vacuum port can be in one of the first set of walls or the second set of walls disposed at the first side. In an implementation, only one of the first set of walls or the second set of walls can include couplant and vacuum ports. In this implementation, this configuration can capture or suppress any air bubbles that may rise within a couplant cavity of the couplant feeding circuit due to a buoyant force. 
     In an implementation, when the couplant feeding circuit plate having the couplant port and the vacuum port disposed on the first side couples with a wedge, the first side of the couplant feeding circuit plate is a first distance from a top surface of the wedge and the second side is a second distance from the top surface of the wedge. In an implementation, the first distance can be less than the second distance such that first side of the couplant feeding circuit plate is closer to the wedge top surface than the second side of the couplant feeding circuit plate. In this implementation, this configuration can capture or suppress any air bubbles that may rise within a couplant cavity of the couplant feeding circuit due to a buoyant force when the couplant feeding circuit plate is inclined. 
     In another implementation, the couplant feeding circuit plate can include couplant ports on a first side of the plate and a second side of the plate. Moreover, in another implementation, the couplant feeding circuit plate can include vacuum ports on the first side of the couplant feeding circuit plate and the second side of the couplant feeding circuit plate. 
    
    
     
       BRIEF DESCRIPTION OF FIGURES 
         FIG.  1    illustrates a NDT apparatus, in accordance with examples of the present disclosure. 
         FIG.  2 A  illustrates a couplant feeding circuit plate of the NDT apparatus shown with reference to  FIG.  1   , in accordance with examples of the present disclosure. 
         FIG.  2 B  is a side view of the NDT apparatus shown with reference to  FIG.  1   , in accordance with examples of the present disclosure. 
         FIG.  2 C  illustrates a couplant feeding circuit plate of the NDT apparatus shown with reference to  FIG.  1   , in accordance with examples of the present disclosure. 
         FIGS.  3  and  4    are side views of the NDT apparatus shown with reference to  FIG.  1   , in accordance with examples of the present disclosure. 
         FIG.  5    is a cut-away view of the couplant feeding plate shown with reference to  FIGS.  2 A and  2 C , in accordance with examples of the present disclosure. 
         FIGS.  6 A and  6 B  are bottom views of the couplant feeding plate shown with reference to  FIGS.  2 A and  2 C , in accordance with examples of the present disclosure. 
         FIG.  7    is a bottom view of the couplant feeding plate shown with reference to  FIGS.  2 A and  2 C , in accordance with examples of the present disclosure. 
         FIG.  8    is a cut-away view of the couplant feeding plate shown with reference to  FIGS.  2 A and  2 C , in accordance with examples of the present disclosure. 
         FIG.  9    is a bottom view of the couplant feeding plate shown with reference to  FIGS.  2 A and  2 C , in accordance with examples of the present disclosure. 
         FIG.  10    illustrates an alternative implementation of a NDT apparatus, in accordance with examples of the present disclosure. 
         FIGS.  11  and  12    illustrate alternative implementations of a couplant feeding circuit plate, in accordance with examples of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Examples of the present disclosure provide a couplant feeding circuit plate that can be used with a device that inspects an article using NDT. Couplant is pushed to an area of the article being inspected and pulled from the area being inspected in a closed loop via the couplant feeding circuit plate. In an implementation, the couplant feeding circuit plate can include a housing defined by a first set of walls extending from a bottom surface of the couplant feeding circuit plate and a second set of walls extending from the bottom surface of the couplant feeding circuit plate and between the first set of walls. Moreover, the couplant feeding circuit plate can include a membrane that extends between the first set of walls and the second set of walls where the first set of walls, the second set of walls, and the membrane form a couplant cavity that can be placed in proximity with an article to be inspected. In an implementation, the couplant feeding circuit plate can include a couplant port and a vacuum port disposed in one of the first set of walls and the second set of walls. In an implementation, the couplant port allows pushing of a couplant to the couplant cavity while the vacuum port allows removal of couplant from the couplant cavity. In an implementation, in addition to pulling the couplant, the vacuum port can pull air bubbles that may be present in the couplant cavity. 
     Now making reference to the Figures, and more specifically  FIG.  1   , a NDT apparatus  100  is shown in accordance with an implementation. The NDT apparatus  100  can include a couplant feeding circuit plate (CFCP)  104  along with a wedge  102 . In some implementations, as will be discussed below, the wedge  102  can be configured to allow couplant to be pushed to the CFCP  104 . Moreover, as will be discussed further below, the wedge  102  can be configured to allow couplant to be pulled from the CFCP  104 . The NDT apparatus can also include a couplant inlet  106  and vacuum inlets  108  that couple with vacuum hoses  110  (only one is shown in  FIG.  1   ). 
     In an implementation, the CFCP  104  can include a first set of sidewalls  112  and a second set of sidewalls  114 . Throughout this document, reference may be made to the first set of sidewalls  112  and the sidewall  112 . It should be noted that reference to the first set of sidewalls  112  and the sidewall  112  can be used interchangeably. Similarly, throughout this document, reference may be made to the second set of sidewalls  114  and the sidewall  114 . It should be noted that reference to the second set of sidewalls  114  and the sidewall  114  can be used interchangeably. In an implementation, the first set of sidewalls  112  and the second set of sidewalls  114  can form a housing  116  that extends circumferentially around a couplant cavity  200 , as shown with reference to  FIGS.  2 A- 2 C . In an implementation, the housing  116  can include a wall, such as the sidewall  112 , the sidewall  114 , or both the sidewall  112  and the sidewall  114 . Throughout this document, reference will be made to elements being disposed within the sidewall  112  and the sidewall  114 . It should be noted that when an element is described as being disposed within the sidewall  112  and/or the sidewall  114 , this also can refer to the element being disposed in a wall of the housing  116 . As may be seen with reference to  FIG.  2 A , the second set of sidewalls  114  can extend between the first set of sidewalls  112  such that the couplant cavity  200  can be defined by the sidewalls  112  and  114  ( FIG.  2 B ). 
     Moreover, as may be seen with regards to  FIGS.  2 B and  2 C , the couplant cavity  200  can also be enclosed by a membrane  202  that extends between the sidewalls  112  and  114 . As such, the couplant cavity  200  can be formed by the sidewalls  112  and  114  and the membrane  202 . The membrane  202  can be formed from any elastomer suitable for ultrasonic inspection. In particular, the couplant pushed into the couplant cavity  200  can have a first acoustic impedance. In an implementation, the membrane  202  can have a second acoustic impedance similar to the first acoustic impedance of the couplant. In implementations where the couplant is water, the membrane  202  can be Aqualene™. 
     As noted above, the NDT apparatus  100  can include the vacuum inlet  108  that can couple to the wedge  102 . In an implementation, a partial vacuum source (not shown) can pull couplant from the wedge  102  and the CFCP  104  via the vacuum inlet  108 . Thus, the vacuum inlet  108  allows for the removal of couplant from the couplant cavity  200 . The vacuum inlet  108  can be any type of coupling that facilitates the coupling of the vacuum hose  110  to the wedge  102 , such as a Milton style coupler, a quick connect hose coupling, or the like. Moreover, the vacuum inlet  108  can be in fluid communication with a vacuum port  300  disposed within the wedge  102 , as shown with reference to  FIG.  3   . In an embodiment, the vacuum inlet  108  can be coupled to a vacuum source (not shown) via the vacuum hose  110 . As will be discussed in further detail below, the vacuum source operates to pull couplant pushed to the CFCP  104  via the couplant inlet  106  during operation of the NDT apparatus  100 . More specifically, the vacuum source pulls the couplant via the vacuum inlet  108  and the vacuum port and  300 . 
     As previously mentioned, the NDT apparatus  100  can include the couplant inlet  106  that can couple to the wedge  102 . In an implementation, a couplant source (not shown) can push couplant into the wedge  102  and the CFCP  104  via the couplant inlet  106 . The couplant inlet  106  can be any type of coupling that facilitates the coupling of a couplant source to the wedge  102 , such as a female/male coupler, a quick connect hose coupling, or the like. In an implementation, the wedge  102  can include a couplant port  400  that is in fluid communication with the couplant inlet  106 , as shown with reference to  FIG.  4   . In an implementation, the couplant inlet  106  receives a couplant from a couplant source (not shown) and facilitates passage of the couplant to the wedge couplant port  400 . The wedge couplant port  400  passes the couplant through the wedge  102  and to the CFCP  104 . In an implementation, examples of couplant can include water, gel, or oil. 
     In an implementation, the NDT apparatus  100  can include a probe  402  disposed within a couplant chamber  404  defined within the wedge  102 . In an embodiment, the probe  402  can include any type of ultrasonic transducer. For example, the probe  402  can include either a single element immersion transducer having a wavelength layer or an array of single element immersion transducers having a wavelength later acoustically matched with a couplant disposed within the couplant chamber  404 , such as water. Such transducers are available from Olympus Corporation of the Americas headquartered in Center Valley, PA. 
     During operation of the NDT apparatus  100 , couplant is pushed into the couplant cavity  200  while the NDT apparatus  100  inspects an article  406 . However, air bubbles  407  may form within the couplant cavity  200  during inspection of the article  406 . The air bubbles  407  may become trapped within the couplant cavity  200  when the NDT apparatus  100  is first placed on a surface  408  of the article  406 . Furthermore, the article surface  408  may be uneven such that when the NDT apparatus  100  passes over the uneven portion of the article surface  408 , the air bubbles  407  may become trapped within the couplant cavity  200 . 
     During ultrasonic testing, sound waves traveling through a couplant reflect in predictable ways off of flaws such as cracks and voids that can be present in the article  406  or the article surface  408 . In particular, sound waves from the probe  402  couple to the article  406  via couplant in the couplant cavity  200 , the membrane  202 , and the couplant chamber  404 . Sound waves travel through the couplant in each of the chambers  200  and  404  and through the membrane  202 . The sound waves are reflected from the article  406  and are processed to create a waveform display that can be used to identify defects in the article  406 . The probe  402  generates and processes ultrasonic signals that can be used to create a waveform display that can be used to identify hidden defects in the article  406 . A characteristic reflection pattern can be identified from an article that does not have defects, and then this may be used to identify changes in the reflection pattern that may indicate defects. However, if the air bubbles  407  are present within the couplant cavity  200 , the air bubbles  407  can create reflectional attenuations, which can cause inaccurate readings of the article  406  and the creation of an inaccurate waveform display and hence the misidentification of potential defects in the article  406 . 
     In an implementation, the CFCP  104  is configured to remove air bubbles from the couplant cavity  200  during operation of the NDT apparatus  100 . Making reference to  FIGS.  5  and  6 A , the CFCP  104  can include vacuum ports  500  along with vacuum ports  600 . The CFCP vacuum ports  500  can be in fluid communication with the wedge vacuum ports  300  of the wedge  102 . As may be seen with reference to  FIG.  6 A , the CFCP vacuum ports  600  can extend between the couplant cavity  200  and the CFCP vacuum ports  500 . In an implementation, the CFCP vacuum ports  600  can be recessed within a surface  700  of the CFCP  104 , as shown with reference to  FIG.  7   . Thus, in an embodiment, the CFCP vacuum ports  600  can form a passageway within the CFCP  104  that can extend between the couplant cavity  200  and the CFCP vacuum ports  500 . 
     In addition, the CFCP  104  can include CFCP couplant ports  602  along with couplant ports  604  as shown with reference to  FIGS.  6 A and  8   . In an implementation, the CFCP couplant ports  602  can be in fluid communication with the couplant inlet  106  and the wedge couplant port  400  such that the CFCP couplant ports  602  can receive couplant from the couplant inlets  106 . Therefore, the CFCP couplant ports  602  can allow for the pushing of couplant into the couplant cavity  200 . As can be seen with reference to  FIG.  6 A , the CFCP couplant ports  604  can extend between the CFCP couplant ports  602  and the couplant cavity  200 . In an implementation, the CFCP couplant ports  604  can be recessed within CFCP surface  700 , as shown with reference to  FIG.  7   . Thus, in an implementation, the CFCP couplant ports  604  can form a passageway within the CFCP  104  that extends between the couplant cavity  200  and the CFCP couplant ports  602 . In an implementation, the CFCP couplant ports  602  and  604  can form a couplant feeding circuit where the CFCP couplant ports  602  and  604  can provide couplant to the couplant cavity  200 . 
     As noted above, the CFCP  104  can function to remove air bubbles from the couplant cavity  200  during inspection of the article  406 . In particular, making reference to  FIG.  6 A , couplant can be pushed or routed into the couplant cavity  200  via the CFCP couplant ports  602  and CFCP couplant ports  604  as shown with directional arrows  606 . The couplant within the couplant cavity  200  is used by the probe  402  to determine the existence of any defects of the article  406  during inspection of the article  406 , as noted above. Moreover, the couplant can be pulled or routed from the couplant cavity  200  via the CFCP couplant vacuum ports  600 , as denoted by directional arrows  608 . Specifically, a vacuum source coupled with the CFCP vacuum ports  500  and  600  creates a negative pressure acting through the CFCP vacuum ports  500  and  600 , thereby pulling the couplant from the couplant cavity  200 . It should be noted that the couplant is present within the couplant cavity  200  long enough for accurate inspection of the article  406 . In an implementation, when the couplant is pulled from the couplant cavity  200  via the CFCP vacuum ports  600 , any air bubbles within the couplant cavity  200 , such as the air bubbles  407 , can be pulled from the couplant cavity  200 . 
     In the implementation shown with regards to  FIG.  6 A , a side  620  of the CFCP  104  only includes the CFCP vacuum ports  500 , the CFCP vacuum ports  600 , the CFCP couplant ports  602 , and the CFCP couplant ports  604  while a side  622  of the CFCP  104  is free of these features. However, in an implementation, each of the CFCP sides  620  and  622  can include the CFCP vacuum ports  500 , the CFCP vacuum ports  600 , the CFCP couplant ports  602 , and the CFCP couplant ports  604 , as shown with respect to  FIG.  6 B . Moreover, in an implementation, the CFCP vacuum ports  500  and the CFCP vacuum ports  600  can only be located one of the CFCP sides  620  or  622  while the CFCP couplant ports  602  and the CFCP couplant ports  604  can be on both the CFCP side  620  and the CFCP side  622 . Alternatively, the CFCP vacuum ports  500  and the CFCP vacuum ports  600  can located at both the CFCP side  620  and the CFCP side  622  while the CFCP couplant ports  602  and the CFCP couplant ports  604  can only be located on one of the CFCP side  620  and the CFCP side  622 . 
     In an implementation, couplant is provided into the couplant cavity  200  via the couplant inlet  106 , the wedge couplant port  400 , and the CFCP couplant ports  602 . Any type of device can be used to provide couplant into the couplant cavity  200  via the couplant inlet  106 , the wedge couplant port  400 , and the CFCP couplant ports  602 . For example, any type of pump that can move fluid through a circuit such as a circuit created by the couplant cavity  200 , the couplant inlet  106 , the wedge couplant port  400 , and the CFCP couplant ports  602  may be used to provide couplant. The CFCP couplant port  604  is in fluid communication with the CFCP couplant port  602  and extends therefrom to the couplant cavity  200 . Thus, the couplant provided to the CFCP couplant port  602  is routed into the couplant cavity  200  via the CFCP couplant port  604  as shown with directional arrows  606  in  FIG.  6 A . 
     While the couplant is being routed (e.g. pumped) into the couplant cavity  200  and is disposed within the couplant cavity  200 , the probe  402  can be used to inspect the article  406  for any defects. Making reference again to  FIG.  4   , the NDT apparatus  100  can include the couplant chamber  404  that can be filled with a couplant. In an implementation, the couplant chamber  404  can be separated from the couplant cavity  200  via the membrane  202  such that the membrane  202  separates the couplant cavity  200  from the couplant chamber  404 . However, as mentioned above, the membrane  202  can have an acoustic impendence similar to a couplant disposed within the couplant cavity  200  and the couplant chamber  404 . Therefore, the membrane  202  does not substantially interfere with acoustic transmissions between couplants in each of the couplant cavity  200  and the couplant chamber  404 . Similar to the couplant provided to the couplant cavity  200 , examples of couplant in the couplant chamber  404  can include water, gel, or oil. In an implementation, the couplant in the couplant cavity  200  and the couplant chamber  404  can be the same. In an implementation, the couplant within the couplant chamber  404  and the couplant cavity  200  can function as a delay between an initial pulse from the probe  402  and a surface signal from the article  406  during ultrasonic scanning. The surface signal can be a reflection of the initial pulse from the article surface  408 . 
     Moreover, as the couplant is being routed into the couplant cavity  200 , a vacuum is applied to the wedge vacuum port  300  and the CFCP vacuum port  600 . Any type of device may be used to apply vacuum at the wedge vacuum port  300  and the CFCP vacuum port  600 . Examples of devices that may be used to create a vacuum at the wedge vacuum port  300  and the CFCP vacuum port  600  include various types of vacuum pumps to create a suction. For example, a vacuum pump or any negative pressure source that can create any type of vacuum or negative pressure with a small flow rate can be used. Any type of vacuum pump or negative pressure source known to those skilled in the art may be used. Further examples may include rotary vane single or dual stage lubricated pumps, such as oil lubricated pumps, or nonlubricated pumps. It should be noted that throughout this document, reference to a vacuum source can also include a negative pressure source. Moreover, any type of vacuum pump that can be modified to accept different flow rates based on a surface and area to be inspected can also be used. The vacuum applied at the wedge vacuum port  300  and the CFCP vacuum port  600  pulls or routes the couplant that is within the couplant cavity  200  into the CFCP vacuum ports  600  along the directional arrows  608  during ultrasonic scanning by the probe  402 . In an implementation, as the couplant is pulled from the couplant cavity  200 , air bubbles, such as the air bubbles  407 , that are present in the couplant cavity  200  are also pulled from the couplant cavity  200  by virtue of the vacuum being applied at the wedge vacuum port  300  and the CFCP vacuum port  600 . Thus, the problems discussed above that air bubbles create during inspections of articles are minimized since air bubbles are pulled from the couplant cavity  200 . More specifically, air bubbles can be removed such that the air bubbles do not interfere with the surface signals reflected from the article surface  408 . 
     During inspection of the article  406 , couplant within the couplant cavity  200  may escape the couplant cavity  200 . In order to contain couplant within the couplant cavity  200 , the CFCP  104  can include a gasket  412  and a gasket  414 , as shown with reference to  FIGS.  4  and  9   . In an embodiment, each of the gaskets  412  and  414  can be formed from the same material or different materials. For example, each of the gaskets  412  and  414  can be formed of foam and Polytetrafluoroethylene. In addition, each of the gaskets  412  and  414  can be formed from Aqualene™. Regardless of the material used to form the gaskets  412  and  414 , the gaskets  412  and  414  can function to contain couplant within the couplant cavity  200  during inspection of the article  406  with the NDT apparatus  100 . In some implementations, the gaskets  412  and  414  can compress such that the CFCP  104  can sealingly engage with the article  406  during inspection. Moreover, in some embodiments, the CFCP  104  can include pins  624  ( FIG.  6 A ) that can limit an amount of compression of the gaskets  412  and  414 . 
     Making reference to  FIGS.  6 A,  7 , and  9   , in an embodiment, the CFCP  104  can include walls  610 - 614  that can function to hold the gaskets  412  and  414  in the CFCP  104 . In an embodiment, the walls  610 - 614  can extend away from the CFCP surface  700  where the walls  610  and  612  can form a groove  616 . In addition, the walls  610  and  614  can form a groove  618 . As shown with reference to  FIG.  9   , the gasket  414  can be disposed within the groove  616  defined by the walls  610  and  612  such that walls  610  and  612  can hold the gasket  414  in the CFCP  104  via the groove  616 . Moreover, as shown with reference to  FIG.  9   , the gasket  412  can be disposed within the groove  618  defined the walls  610  and  614  such that the walls  610  and  614  can hold the gasket  412  in the CFCP  104  via the groove  618 . 
     When the couplant, which can include air bubbles, is pulled from the couplant cavity  200  via the vacuum inlet  108 , the CFCP vacuum port  500 , and the CFCP vacuum port  600 , the pulled couplant can be provided to a filtration device that can extract air bubbles from the couplant prior to feeding the couplant back to the couplant source that provides couplant to the CFCP couplant port  602 . Examples of devices that may be used to filter air bubbles from the couplant recovered from the NDT apparatus  100  include any type of filter with an air separator or even a tank configured to allow the air bubbles rise to a surface of fluid within the tank. Moreover, once the air bubbles are separated from the couplant, the device can return the couplant to the couplant source. Thus, a closed loop is formed where the closed loop includes the couplant inlet  106 , the wedge couplant port  400 , the CFCP couplant ports  602 , the CFCP couplant ports  604 , the couplant cavity  200 , the CFCP vacuum ports  600 , and the CFCP vacuum port  500 . Moreover, the CFCP  104  can have a closed loop formed from the CFCP  104 , the CFCP couplant ports  602 , the CFCP couplant ports  604 , the couplant cavity  200 , the CFCP vacuum ports  600 , and the CFCP vacuum ports  500 . 
     During use of the NDT apparatus  100 , couplant may escape the couplant cavity  200 . In some implementations, in order to limit the amount of couplant that escapes from the NDT apparatus  100  during inspection, such as couplant that is left on a surface of the article  406  after the NDT apparatus  100  passes over the article  406 , the gaskets  412  and  414  can be next to each other and can form a couplant suction circuit  900 , as shown with reference to  FIG.  9   . In an implementation, the suction circuit  900  can include suction ports  628 , as shown with reference to  FIGS.  6 A and  9   . The suction ports  628  can be in fluid communication with the vacuum source and the device that removes the air bubbles from the couplant and returns the couplant to the couplant source to which the CFCP vacuum ports  500  are coupled. As shown with regards to  FIG.  9   , the suction circuit  900  is formed between an outer periphery of the gasket  414  and an inner periphery of the gasket  412 . During operation of the NDT apparatus  100 , couplant that escapes the couplant cavity  200  may be pulled away from the article  406 , i.e., sucked up, from the article  406  by the suction ports  628  in the couplant suction circuit  900 . 
     In some embodiments, when the CFCP  104  couples to a wedge of a NDT apparatus, a bottom surface of the NDT apparatus may be placed in a position along article  406  such that the CFCP  104  is inclined. To further illustrate, reference is now made to  FIG.  10   , which illustrates an NDT apparatus  1000  having the CFCP  104 , in accordance with an implementation. As noted above with reference to  FIG.  6 A , in an implementation, the CFCP side  620  can have the CFCP vacuum ports  500 , the CFCP vacuum ports  600 , such as to capture or suppress any air bubbles that may rise within the couplant cavity due to a buoyant force, with the CFCP inclined as shown. The region  620  can also include the CFCP couplant ports  602 , and the CFCP couplant ports  604  while the CFCP side  622  is free of the CFCP vacuum ports  500 , the CFCP vacuum ports  600 , the CFCP couplant ports  602 , and the CFCP couplant ports  604 . In an implementation, the NDT apparatus  1000  can have a configuration where the CFCP side  620  is closer to the couplant inlet  106  and the vacuum inlet  108 , as shown with reference to  FIG.  10   . More specifically, the CFCP side  620  can be located a distance D 1002  from an upper surface  1004  of a wedge  1006  of the NDT apparatus  1000 . Moreover, in this implementation, the CFCP side  622  can be a distance D 1004  away from the wedge upper surface  1004 . It should be noted that in an implementation, the NDT apparatus can be used at angle and any focal distance. 
     In some of the implementations discussed above, the CFCP  104  is in fluid communication with a couplant source via the wedge  102 . In addition, in some of the implementations discussed above, the CFCP  104  is in fluid communication with a vacuum source via the wedge  102 . In further implementations, a CFCP having the CFCP vacuum ports  500 , the CFCP vacuum ports  600 , the CFCP couplant ports  602 , and the CFCP couplant ports  604  may directly couple with a couplant source. Moreover, in further implementations, a CFCP having the CFCP vacuum ports  500 , the CFCP vacuum ports  600 , the CFCP couplant ports  602 , and the CFCP couplant ports  604  may directly couple with a vacuum source. Additionally, in further implementations, a CFCP having the CFCP vacuum ports  500 , the CFCP vacuum ports  600 , the CFCP couplant ports  602 , and the CFCP couplant ports  604  may directly couple with both a couplant source and a vacuum source. For example, in some implementations, the CFCP vacuum source ports  1100  may be disposed within a CFCP  1102 , as shown with reference to  FIG.  11   . In particular, the CFCP vacuum source ports  1100  may couple with a vacuum source and a device that removes the air bubbles from the couplant and returns the couplant to the couplant source as discussed above. In this implementation, the CFCP couplant outlets may still couplant source via a wedge, such as the wedges  102  and  1006  described above. In implementations where both sides of a CFCP include vacuum ports and vacuum ports, the CFCP may include CFCP vacuum source ports on both sides of the CFCP. 
     In further implementations, a CFCP can couple directly with both a couplant source and a vacuum device that removes the air bubbles from the couplant and returns the couplant to the couplant source as discussed above. For example, a CFCP  1200  can include CFCP couplant source ports  1202  that couple directly with a couplant source as discussed above along with the CFCP vacuum source ports  1100 . In implementations where both sides of a CFCP include couplant ports, couplant ports, vacuum ports, and vacuum ports, the CFCP may include CFCP couplant source ports and CFCP vacuum source ports on both sides of the CFCP. 
     Thus, the NDT apparatuses  100  and  1000  according to the present disclosure comprises vacuum ports and couplant ports that can keep almost all of the couplant, such as water, within the NDT apparatus. Moreover, couplant used to fill the couplant chamber  404  can be constant where no couplant will be entering or exiting the probe chamber during use of the NDT apparatus  100  or  1000 . Also, during operation of the NDT apparatuses  100  and  1000 , couplant that can be used to fill the couplant cavity  200  can be recirculated. Thus, little to no couplant is wasted during use. 
     As noted above, the NDT apparatuses  100  and  1000  can include the CFCP vacuum ports  500  along with the CFCP vacuum ports  600 . Therefore, any air bubbles within the couplant cavity  200  that could potentially cause problems during use of the NDT apparatuses  100  and  1000  can be removed. As described above, the couplant cavity  200  can be surrounded by a water feeding circuit formed by the CFCP couplant ports  604  and CFCP vacuum ports  500  where the CFCP couplant ports  604  supply couplant that is routed into the couplant cavity  200  and the CFCP vacuum ports  500  pull the couplant along with any air bubbles that form during filling of the couplant cavity  200  and placement of the NDT apparatuses on article to be inspected. In addition, a compression thickness of the gaskets  412  and  414  help to prevent air bubble formation. The compression thickness of the gaskets  412  and  414  can be managed with the pins  624  such that the gaskets  412  and  414  can sustain a compression between about 1 mm and about 2 mm. Accordingly, the NDT apparatuses  100  and  1000  can be used to inspect structures that have a curved configuration since the gaskets  412  and  414  can adapt to the height differences imparted by curved surfaces. 
     Additionally, during inspection, multiple NDT apparatuses  100  or  1000  may be used to inspect a single structure. During operation, the NDT apparatuses  100  or  1000  are placed where the CFCP vacuum ports  500  are at the top of the NDT apparatuses  100  and  1000  such that any air bubbles within the couplant cavity  200  draft upward and can be sucked out. 
     Upon completion of an inspection of a structure, the NDT apparatuses  100  and  1000  can remove almost all couplant from the couplant cavity  200  by no longer feeding couplant through the CFCP couplant ports  602  while still being connected to a vacuum. Thus, when the NDT apparatus  100  or  1000  is removed from an inspected article, there is very little “wetness” left behind because the couplant cavity  200  has been emptied. 
     The above detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show, by way of illustration, specific examples in which the invention can be practiced. These examples are also referred to herein as examples. Such examples can include elements in addition to those shown or described. However, the present inventor also contemplates examples in which only those elements shown or described are provided. Moreover, the present inventor also contemplates examples using any combination or permutation of those elements shown or described (or one or more aspects thereof), either with respect to a particular example (or one or more aspects thereof), or with respect to other examples (or one or more aspects thereof) shown or described herein. 
     In this document, the terms a or an are used, as is common in patent documents, to include one or more than one, independent of any other instances or usages of at least one or one or more. In this document, the term or is used to refer to a nonexclusive or, such that A or B includes A but not B, B but not A, and A and B, unless otherwise indicated. In this document, the terms including and in which are used as the plain-English equivalents of the respective terms comprising and wherein. Also, in the following claims, the terms including and comprising are open-ended, that is, a system, device, article, composition, formulation, or process that includes elements in addition to those listed after such a term in a claim are still deemed to fall within the scope of that claim. Moreover, in the following claims, the terms first, second, and third, etc. are used merely as labels, and are not intended to impose numerical requirements on their objects. 
     The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other examples can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed example. Thus, the following claims are hereby incorporated into the Detailed Description as examples or examples, with each claim standing on its own as a separate example, and it is contemplated that such examples can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.