In an example, a mandrel for a composite part includes an upper-mandrel portion, a lower-mandrel portion, and a mid-mandrel portion between the upper-mandrel portion and the lower-mandrel portion. The mandrel also includes a cavity and an exterior surface defined by the upper-mandrel portion, the lower-mandrel portion, and the mid-mandrel portion. An actuator is movable in the cavity between a first position and a second position. The exterior surface can support the composite part. A perimeter of the exterior surface has a first length when the actuator is in the first position and the perimeter has a second length when the actuator is in the second position. The first length is greater than the second length such that the mandrel is in an expanded state when the actuator is in the first position and the mandrel is in a contracted state when the actuator is in the second position.

In an example, a mandrel for a composite part includes an upper-mandrel portion, a lower-mandrel portion, and a mid-mandrel portion between the upper-mandrel portion and the lower-mandrel portion. The mandrel also includes a cavity and an exterior surface defined by the upper-mandrel portion, the lower-mandrel portion, and the mid-mandrel portion. An actuator is movable in the cavity between a first position and a second position. The exterior surface can support the composite part. A perimeter of the exterior surface has a first length when the actuator is in the first position and the perimeter has a second length when the actuator is in the second position. The first length is greater than the second length such that the mandrel is in an expanded state when the actuator is in the first position and the mandrel is in a contracted state when the actuator is in the second position.

There is provided a crack repairing method for suppressing a crack growth in a wall portion. The crack repairing method includes an injection step in which working fluid is injected into a crack formed into a surface of the wall portion of a target object and a vibration step in which vibration is applied to the working fluid in a direction from an crack initiation portion of the crack on the surface to an inner end portion of the crack. The crack repairing method further includes a deformation step in which a cavity is generated in the working fluid by the applied vibration and compressive residual stress is generated at the inner end portion of the crack.

There is provided a crack repairing method for suppressing a crack growth in a wall portion. The crack repairing method includes an injection step in which working fluid is injected into a crack formed into a surface of the wall portion of a target object and a vibration step in which vibration is applied to the working fluid in a direction from an crack initiation portion of the crack on the surface to an inner end portion of the crack. The crack repairing method further includes a deformation step in which a cavity is generated in the working fluid by the applied vibration and compressive residual stress is generated at the inner end portion of the crack.

The invention relates to a repaired plastic product comprising a body (1) made from a first plastic material (2) and at least one repaired segment having a second plastic material (3) comprising particles designed to be visible under the application of light (4) comprised in the infrared or ultraviolet electromagnetic spectrum.

Complex laminated composites may be repaired by removal of individual damaged plies through peeling in order to exploit the weaker interlaminar properties of these composites. Upon removal of the individual damaged plies through peeling, replacement plies may be added to restore the laminated composite. In addition, when damage extends through the thickness of a laminated composite, a plug may be used to allow plies to be replaced while maintaining contour within the repair region. A caul plate also may be used to stiffen and maintain the contour of a repair region while peeling and removing plies from the repair region.

Complex laminated composites may be repaired by removal of individual damaged plies through peeling in order to exploit the weaker interlaminar properties of these composites. Upon removal of the individual damaged plies through peeling, replacement plies may be added to restore the laminated composite. In addition, when damage extends through the thickness of a laminated composite, a plug may be used to allow plies to be replaced while maintaining contour within the repair region. A caul plate also may be used to stiffen and maintain the contour of a repair region while peeling and removing plies from the repair region.

The present invention is an automated wind turbine servicing system that includes a rover, and uses an active electro-mechanical gripping roller system to attach to the horizontally positioned airfoil and navigate along it in order to clean, inspect, service (paint, remove material or repair), or otherwise maintain the wind turbine airfoil. An electromechanical compression system adapts to various turbine airfoil profiles so that it can be used to service many different types of wind turbines. The rover operates on a horizontal airfoil rather than a vertical airfoil to utilize gravity and prevent movement along the chord of the airfoil. Once secured to the airfoil, the rover activates a drive system that propels the rover along the airfoil as it travels along the upper edge, using wind pressure, the rover wheels' frictional adherence to the airfoil, and gravity to assist in coupling the rover to the airfoil. The rover, which preferably includes a robotic arm, is able to utilize multiple tools to perform various tasks such as inspecting, cleaning, sanding, repairing, painting and laying leading edge protection tape as well as vortex generators on the surface of the airfoil.

A method for repair of a damaged stiffened panel of isogrid type, wherein the repair method comprises a step of removal of material with the aim of removing at least one damaged rib and also steps of fitting at least one structural reinforcement connecting at least two nodes positioned about the damaged zone and of at least one wall reinforcement connecting the wall of the stiffened panel and the structural reinforcement.

A method for repair of a damaged stiffened panel of isogrid type, wherein the repair method comprises a step of removal of material with the aim of removing at least one damaged rib and also steps of fitting at least one structural reinforcement connecting at least two nodes positioned about the damaged zone and of at least one wall reinforcement connecting the wall of the stiffened panel and the structural reinforcement.