Containment structure

A containment casing for blocking the movement of particles originating in the axially extending flow path of a gas turbine engine, the particles having a radial component of velocity, which comprises:

• an inner casing which has an exterior and which extends circumferentially about the axially extending flow path;
• a fabric including
• a plurality of layers of material which extend circumferentially about the exterior of the inner casing, each layer having
• a first end,
• a second end,
• a first mass per unit length in a first portion of the layer, and
• a second mass per unit length in a second portion of the layer which is smaller than the first mass per unit length,
• a first ribbon of material attached to a pair of layers at the first ends of the pair of layers the first ribbon having a first strip and a second strip spaced from the first strip leaving a gap therebetween, and
• a second ribbon of material attached to a pair of layers of material at the second ends of the pair of layers, the second ribbon having a first strip and a second strip spaced from the first strip leaving a gap therebetween;
• and
• means for applying a load to the fabric which includes
• a first bar adapted to engage the strips of the first ribbon and a second bar adapted to engage the strips of the second ribbon,
• means for bringing the bars closer together which engages the first bar and the second bar and which extends through the gaps between the strips.

A flexible casing for blocking the movement of particles having a radial component of velocity, which comprises:

• a fabric which is adapted to extend circumferentially about an axially extending region containing said particles, the fabric having
• a first end,
• a second end,
• a first mass per unit length in a first portion of the fabric, and
• a second mass per unit length in a second portion of the fabric which is smaller than the first mass per unit length;
• and,
• means for applying a load to the first end and the second end which engages the ends to place the fabric in tension.

A flexible casing for blocking the movement of particles orginating in the axially extending flow path of a gas turbine engine, the particles having a radical component of velocity, which comprises:

• a fabric including
• a plurality of layers of material which is adapted to extend circumferentially about the axially extending flow path, each layer having
• a first end,
• a second end,
• a first mass per unit length in a first portion of the layer, and
• a second mass per unit length in a second portion of the layer which is smaller than the first mass per unit length;
• and,
• a first ribbon of material attached to a pair of layers at the first ends of the pair of layers, the first ribbon having a first strip and a second strip spaced from the first strip leaving a gap therebetween and,
• a second ribbon of material attached to a pair of layers of material at the second ends of the pair of layers, the second ribbon having a first strip and a second strip spaced from the first strip leaving a gap therebetween;
• and
• means for applying a load to the fabric which includes
• a first bar adapted to engage the strips of the first ribbon and a second bar adapted to engage the strips of the second ribbon,
• means for bringing the bars closer together which engages the first bar and the second bar and which extends through the gaps between the strips.

A method of forming a containment case for a rotary machine, the containment case including a fabric extending circumferentially about a first casing, the fabric having circumferential length and axial length, including the steps of:

• wrapping a fabric about the first casing, the fabric having a first mass per unit length in the leading edge region of the fabric and a second mass per unit length in the remaining portion of the fabric;
• applying a first load to a first portion of the axial length of the fabric which is in the leading edge region to cause an elongation in the circumferential length of the first portion of the fabric;
• and
• applying a second load to a second portion of the axial length of the fabric to cause an elongation in the circumferential length of the second portion of the fabric, the second load being smaller than the first load.