An inspection crawler, and systems and methods for inspecting underwater pipelines are provided. The system includes the inspection crawler having a housing with a first side, an opposing second side, a power source, and a controller. The crawler includes an inspection tool, at least two pairs of latching arms, each latching arm including a rolling element, and at least two pairs of driving wheels. The system also includes at least one communication unit configured to communicate with the inspection crawler and to communicate aerially with one or more remote devices and, and at one sea surface unit. The inspection crawler can further include a connecting structure connecting the front and back portions of the crawler, and configured to elongate and shorten the inspection crawler.

A method for determining a quality of a friction stir welded seam is described. The method involves applying an impact to a welded plate and comparing its damping capacity with the damping capacity of a geometrically equivalent defect-free plate. Damping capacities that differ by a small percent difference indicate that the welded plate is also defect-free. This method is particularly advantageous when dealing with small defects, which produce miniscule changes in natural frequency which may not be measureable.

A method for determining a quality of a friction stir welded seam is described. The method involves applying an impact to a welded plate and comparing its damping capacity with the damping capacity of a geometrically equivalent defect-free plate. Damping capacities that differ by a small percent difference indicate that the welded plate is also defect-free. This method is particularly advantageous when dealing with small defects, which produce miniscule changes in natural frequency which may not be measureable.

A system for underwater inspection including an inspection crawler are provided. The inspection crawler includes a housing having first and second sides, a power source, a controller, an inspection tool, at least two driving wheels, and a moveable center of gravity. A method for traversing a weld joint with the inspection crawler having a moving mass is also provided. In the method, the crawler is parked proximate to the joint, and the mass is slid along a slide rail to the second end of the crawler distal to the joint. The first end of the crawler is then propelled over the joint and the mass is slid to the center of the crawler. A center portion of the crawler is then propelled over the joint and the mass is slid to the first end of the crawler. The second end of the crawler is then propelled over the joint.

There are provided an ultrasonic waveform data generation unit (123) that generates ultrasonic waveform data representing amplitudes of reflected ultrasonic beams received by a reception unit (132) in time series for each of ultrasonic elements (111) forming reception ultrasonic elements (114), an ultrasonic waveform data processing unit (124) that uses a plurality of origin time adjustment patterns, in which a plurality of relative positional relationships between a phased array probe (110) and a welded portion (210) are set, and performs processing to synthesize pieces of the ultrasonic waveform data each having the adjusted origin time to generate synthesized ultrasonic waveform data according to each of the origin time adjustment patterns, and a defect evaluation unit (125) that evaluates whether or not a defect (211) is present in the welded portion (210) based on the synthesized ultrasonic waveform data.

Weld seam testing chain for testing a weld seam by means of ultrasound on two plastic tubes welded together at the ends, comprising standard chain links, wherein the standard chain links are hooked together to form the weld seam testing chain, and the chain can be lengthened or shortened individually, a sensor receptacle for accommodating the ultrasonic sensor, and an adjusting unit for the fine adjustment of the weld seam testing chain length, wherein the standard chain links have a hook on one side and a hook receptacle on the opposite side, thereby enabling the individual chain links to be hooked together.

A method and device for the ultrasonic testing of a weld of an electric arc-welded sleeve (10) for plastic pipes (11), having the following steps: fastening a testing device (1) on the outer contour of the welded plastic pipe (11), comprising a circumferential fastening element (2) and a holder (3), the holder (3) preferably comprising a support (7), a carrier (8) and a gripper (9), and a coupling element with a recess, feeding a liquid, preferably water, into the recess (5) of the coupling element (4),
wherein the recess (5) in the coupling element (4) is fully filled with the liquid, and a constant liquid column is maintained in the coupling element (4) during the ultrasonic testing in order to transmit the ultrasound.

A method for non-destructive inspection of a weld seam. An array of ultrasonic transducers is positioned such that the array of transducers extends over at least part of the width of the weld seam. Each transducer element in the array of transducer elements is excited so that each transducer emits an ultrasonic signal. A plurality of reflected ultrasonic signals are received at the array of transducer elements and the reflected ultrasonic signals are converted to electrical signals. The electrical signals are analyzed to identify a defect, or a plurality of defects.

A scanner assembly for pipeline inspection, having a pipe mounting section and a scanner frame which is laterally displaceable with respect to the pipe mounting section.

An ultrasonic flaw detection device includes: a matrix array probe; an ultrasonic wave transmitting and receiving unit that controls the matrix array probe; and an evaluation unit that detects a planar defect based on the reflected ultrasonic waves received by the ultrasonic wave transmitting and receiving unit. The matrix array probe has a plurality of vibration elements arranged lattice-like, an array pitch of the vibration elements in the pipe axis direction is larger than a wavelength of ultrasonic waves transmitted and received, widths of the vibration elements in the pipe axis direction decrease outward in the pipe axis direction from a pipe axis direction center position of the matrix array probe, and the widths and center coordinates of the vibration elements in the pipe axis direction have been adjusted such that all of ultrasonic waves from the vibration elements overlap in a focal position control range for the ultrasonic waves.