Abstract: An assembly and method for detecting cross bores and the location of underground pipe system assets includes an acoustic generator placed within an interior of the sewer system and an acoustic receiver placed within proximity of the lateral(s) of the pipe system. The acoustic generator generates an acoustic signal to transmit through the interior of a sewer pipe of the sewer system. A controller detects, in response to the acoustic receiver hearing the acoustic signal, a location of the underground pipe.

Abstract: An assembly and method for detecting cross bores involving a sewer system and a gas pipe includes an acoustic generator placed within an interior of the sewer system and an acoustic receiver placed either within an interior of the gas pipe or in proximity to an end of the gas pipe. The acoustic generator generates an acoustic signal to transmit through the interior of a sewer pipe of the sewer system. A controller detects, in response to the acoustic receiver hearing the acoustic signal, a cross bore involving the sewer pipe and the gas pipe. A microphone may be placed within the interior of the sewer system at a location remote from the acoustic generator. In this case, the controller determines, in response to the acoustic receiver not hearing the acoustic signal and the microphone hearing the acoustic signal, that a cross bore involving the sewer pipe and the gas pipe is absent.

Abstract: An electro-magnetic acoustic transducer (EMAT) system and method for controlling the EMAT system are provided. The system includes an electromagnet array with one or more electromagnets. Each electromagnet includes a magnetic core and a wound coil wrapped around the magnetic core. The electromagnet array generates bias magnetic fields having different patterns when the wound coils are energized differently.

Abstract: An electro-magnetic acoustic transducer (EMAT) having an electromagnet array is provided. The electromagnet array includes electromagnets. Each electromagnet includes a magnetic core and a wound coil wrapped around the magnetic core. The electromagnet array generates bias magnetic fields having different patterns when the wound coils are energized differently. For instance, the electromagnet array generates a bias magnetic field having a given pattern, for the EMAT to transmit a first type of ultrasonic wave such as shear-horizontal wave, when the wound coils are energized in a given manner; and generates a bias magnetic field having a different pattern, for the EMAT to transmit a second type of ultrasonic wave such as a Lamb wave, when the wound coils are energized in a different manner.

Abstract: An electro-magnetic acoustic transducer (EMAT) having an electromagnet array is provided. The electromagnet array includes electromagnets. Each electromagnet includes a magnetic core and a wound coil wrapped around the magnetic core. The electromagnet array generates bias magnetic fields having different patterns when the wound coils are energized differently. For instance, the electromagnet array generates a bias magnetic field having a given pattern, for the EMAT to transmit a first type of ultrasonic wave such as shear-horizontal wave, when the wound coils are energized in a given manner; and generates a bias magnetic field having a different pattern, for the EMAT to transmit a second type of ultrasonic wave such as a Lamb wave, when the wound coils are energized in a different manner.

Abstract: An assembly and method for detecting cross bores involving a sewer system and a gas pipe includes an acoustic generator placed within an interior of the sewer system and an acoustic receiver placed either within an interior of the gas pipe or in proximity to an end of the gas pipe. The acoustic generator generates an acoustic signal to transmit through the interior of a sewer pipe of the sewer system. A controller detects, in response to the acoustic receiver hearing the acoustic signal, a cross bore involving the sewer pipe and the gas pipe. A microphone may be placed within the interior of the sewer system at a location remote from the acoustic generator. In this case, the controller determines, in response to the acoustic receiver not hearing the acoustic signal and the microphone hearing the acoustic signal, that a cross bore involving the sewer pipe and the gas pipe is absent.

Abstract: An electro-magnetic acoustic transducer (EMAT) generates both Lamb waves and shear horizontal (SH) waves or Lamb waves only. In configurations, the EMAT includes first and second coils shifted in alignment relative to one another and a magnet array overlaid over the coils. The EMAT generates a Lamb wave when the first coil is excited with an electrical current and generates a SH wave when the second coil is excited with an electrical current. In other configurations, the EMAT includes a coil and a magnet array which are movable relative to one another between a first position and a second position shifted in alignment relative to one another. The EMAT generates a Lamb wave when the coil is excited with an electrical current while in the first position and generates a SH wave when the coil is excited with an electrical current while in the second position.

Abstract: An electro-magnetic acoustic transducer (EMAT) generates both Lamb waves and shear horizontal (SH) waves or Lamb waves only. In configurations, the EMAT includes first and second coils shifted in alignment relative to one another and a magnet array overlaid over the coils. The EMAT generates a Lamb wave when the first coil is excited with an electrical current and generates a SH wave when the second coil is excited with an electrical current. In other configurations, the EMAT includes a coil and a magnet array which are movable relative to one another between a first position and a second position shifted in alignment relative to one another. The EMAT generates a Lamb wave when the coil is excited with an electrical current while in the first position and generates a SH wave when the coil is excited with an electrical current while in the second position.