Abstract: A method for manufacturing a trailer wall includes welding wall members together on a work surface while pressing the wall members with a rotatable roller toward the work surface and cooling the wall members adjacent points of welding there between to reduce bowing of the wall members related to heat created in the wall members by the welding. A related apparatus includes a movable welding unit having a welding tip for welding a pair of wall members together at a plurality of locations while on a work surface. A rotatable roller is pivotally mounted on the welding unit for applying pressure to the wall members toward the work surface adjacent the welding tip while rolling along the wall members. A cooling unit moves liquid or gas coolant to provide the cooling effect. Preferably, the wall members are hollow shiplap panels and the coolant passes through the hollow panels.

Abstract: A wall for a truck bed and particularly for dump trucks includes planks joined to one another along their lengths and a cap member joined to the upper plank along their lengths. Adjacent planks are joined along respective connecting sides by engagement of a pivot of a first plank within a pivot-receiving slot of a second plank, rotation of the planks with respect to one another about the pivot and attachment by snap-fit engagement. The first plank connecting side includes an arcuate wing and the second plank connecting side includes an arcuate extension, the wing and extension being received respectively in a wing-receiving slot formed in the second plank and an extension-receiving slot formed in the first plank during the relative rotation of the planks. The cap member is joined to the upper plank in a similar manner except that attachment is by welding rather than snap-fit engagement.