A method of stretch forming a double curvature panel having corrugations or other surface features formed therein includes providing a reconfigurable forming surface defined by a flexible interpolator sheet mounted on an array of height adjustable pins, the interpolator sheet having a profiled upper surface adapted to form corrugations or other surface features in a workpiece as it is stretched over the forming surface, adjusting the height of each pin to suit the shape of the panel to be produced, placing a workpiece onto the forming surface, and stretching the workpiece over the forming surface such that the profiled upper surface of the interpolator sheet forms the desired corrugations or other surface features in the workpiece.

An exchangeable forming component is configured for removable mounting relative to an interface block of a modular forming tool, with the interface block of the modular forming tool configured for removable mounting relative to a support structure to form a sheet metal component. The exchangeable forming component includes a component structure which is constructed using additive manufacturing, wherein the exchangeable forming component presents a first surface which provides an exchangeable forming surface shaped to form the sheet metal component, and a second surface configured to removably engage the support structure.

An exchangeable forming component is configured for removable mounting relative to an interface block of a modular forming tool, with the interface block of the modular forming tool configured for removable mounting relative to a support structure to form a sheet metal component. The exchangeable forming component includes a component structure which is constructed using additive manufacturing, wherein the exchangeable forming component presents a first surface which provides an exchangeable forming surface shaped to form the sheet metal component, and a second surface configured to removably engage the support structure.

An apparatus for forming a sector of an annular component having an arrangement for securely retaining at least a portion of a blank mountable thereon. The retaining arrangement is adapted for leaving a portion of the retainable blank accessible. A punch is provided having an external surface contour shaped to correspond to the shape of all or a part of the profile of the sector of the annular component from a trailing edge to a leading edge and/or from a leading edge to an inlet edge. The apparatus has a cooperating forming arrangement for forming the profile of the sector of the annular component from the leading edge to the inlet edge. The retaining arrangement is adapted for forming a clamping boundary enclosing the accessible part of the blank to be formed by the punch.

A method of forming a sector of an annular component such as an inlet cowl/lip skin of a nacelle for an aircraft engine. The method comprising the steps of clamping at least part of a blank along a clamping boundary in a retaining arrangement so as to leave a portion of the blank exposed within the clamping boundary. Moving a punch and/or retaining arrangement radially so that the punch comes in to contact with the exposed portion of the blank and through the main body of the exposed blank thereby drawing the blank onto an external surface of the punch forming the sector from the leading edge to the trailing edge. Activating cooperating forming arrangement for engaging the blank and drawing the blank over the punch forming the sector of the inlet cowl from the leading edge to the inlet edge, the method comprising using a second draw forming tooling arrangement for the cooperating forming arrangement.

A method of forming a sector of an annular component such as an inlet cowl/lip skin of a nacelle for an aircraft engine. The method comprising the steps of clamping at least part of a blank along a clamping boundary in a retaining arrangement so as to leave a portion of the blank exposed within the clamping boundary. Moving a punch and/or retaining arrangement radially so that the punch comes in to contact with the exposed portion of the blank and through the main body of the exposed blank thereby drawing the blank onto an external surface of the punch forming the sector from the leading edge to the trailing edge. Activating cooperating forming arrangement for engaging the blank and drawing the blank over the punch forming the sector of the inlet cowl from the leading edge to the inlet edge, the method comprising using a second draw forming tooling arrangement for the cooperating forming arrangement.

An apparatus for forming a sector of an annular component having an arrangement for securely retaining at least a portion of a blank mountable thereon. The retaining arrangement is adapted for leaving a portion of the retainable blank accessible. A punch is provided having an external surface contour shaped to correspond to the shape of all or a part of the profile of the sector of the annular component from a trailing edge to a leading edge and/or from a leading edge to an inlet edge. The apparatus has a cooperating forming arrangement for forming the profile of the sector of the annular component from the leading edge to the inlet edge. The retaining arrangement is adapted for forming a clamping boundary enclosing the accessible part of the blank to be formed by the punch.

An apparatus for forming a sector of an annular component having an arrangement for securely retaining at least a portion of a blank mountable thereon. The retaining arrangement is adapted for leaving a portion of the retainable blank accessible. A punch is provided having an external surface contour shaped to correspond to the shape of all or a part of the profile of the sector of the annular component from a trailing edge to a leading edge and/or from a leading edge to an inlet edge. The apparatus has a cooperating forming arrangement for forming the profile of the sector of the annular component from the leading edge to the inlet edge. The retaining arrangement is adapted for forming a clamping boundary enclosing the accessible part of the blank to be formed by the punch.

A method of forming a compound curvature metal skin includes providing a blank defining at least a sector of a truncated cone, providing an arcuate or annular punch substantially corresponding in shape to an inner surface of the compound curvature metal skin, gripping a leading edge of a sheet metal blank between mating faces of a first blank holder on a first side of the punch, gripping a trailing edge of the blank between mating faces of a second blank holder on a second side of the punch opposite to the first side, displacing the blank holders with respect to the punch to draw the blank over the punch while permitting the blank to flow between mating surfaces of at least one of the blank holders, including displacing each of the blank holders with respect to the punch by different amounts and at different rates.

A method of forming a compound curvature metal skin includes providing a blank defining at least a sector of a truncated cone, providing an arcuate or annular punch substantially corresponding in shape to an inner surface of the compound curvature metal skin, gripping a leading edge of a sheet metal blank between mating faces of a first blank holder on a first side of the punch, gripping a trailing edge of the blank between mating faces of a second blank holder on a second side of the punch opposite to the first side, displacing the blank holders with respect to the punch to draw the blank over the punch while permitting the blank to flow between mating surfaces of at least one of the blank holders, including displacing each of the blank holders with respect to the punch by different amounts and at different rates.