A seal assembly having: a carbon ring annularly extending about a central axis and having an outer face, and a shrink band annularly extending about the central axis, the shrink band having an inner face, the inner face in contact with the outer face of the carbon ring at a contact interface defined therebetween, the inner face of the shrink band protruding axially beyond the contact interface.

A fan device includes a driving device, a fan wheel, and a locking fastener. The driving device includes a shaft. The fan wheel defines a shaft hole to receive the shaft. The locking fastener has a thermal expansion coefficient same as a thermal expansion coefficient of the shaft.

A composite blade formed by laying up composite layers containing reinforcing fiber and resin, the composite blade comprising: a blade root mounted in a blade groove; an airfoil extending from the blade root to a front end side; and a metal patch mounted between the blade groove and the blade root, and bonded to the blade root.

An angular pitch control ring (8) of stator vanes (2), the rotations of which are controlled by a mechanism (6) applying a thrust tangent to the ring (8), is also moved in translation when it is displaced, making it touch the stator (2). According to the invention, one lateral region (13) on one side of the mechanism (6) is constructed to be stiffer than the other region to take account of the larger forces that the mechanism (6) must apply in a direction of movement. Application to turbomachines.

A bearing compartment seal for a gas turbine engine includes at least one seal ring defining an axis and having a radially inward facing sealing surface and a seal runner having a support constructed of a first material and an interface portion constructed of a second material. The interface portion includes a radially outward facing surface. A first coefficient of thermal expansion of the second material is at most approximately equal to a second coefficient of thermal expansion of the at least one seal ring.

A seal assembly is disclosed for sealing a high pressure fluid cavity from a low pressure fluid cavity. The cavities are at least partially disposed between a rotatable shaft and a sump housing. The seal assembly comprises a circumferential runner and a seal ring. The circumferential runner is carried by the shaft and has a radially outward facing seal surface extending axially along the shaft. The seal ring is sealing engaged with the sump housing and has a radially inward facing seal surface that sealingly engages the radially outward facing seal surface of the runner. The runner and the seal ring are formed from materials having coefficients of thermal expansion that are matched to effect sealing engagement between the runner and the seal ring over a predetermined range of operating temperatures.

A gas turbine engine includes an annular structure disposed around an engine central longitudinal axis of the gas turbine engine. The annular structure defines an annular channel and comprises a first density, according to various embodiments. The gas turbine engine may further include a weight-saving filler disposed within the annular channel. The weight-saving filler may have a second density that is less than the first density. The gas turbine engine may further include an annular retention strap disposed around the engine central longitudinal axis of the gas turbine engine. The annular retention strap is at least partially embedded in the weight-saving filler, according to various embodiments.

A ceramic heat shield for a gas turbine. The ceramic heat shield has a ceramic body containing aluminium oxide and has a surface layer of the ceramic body which contains yttrium aluminium garnet as reaction coating material. A gas turbine includes such a ceramic heat shield and a method produces such a ceramic heat shield.

A gas turbine engine includes an annular structure disposed around an engine central longitudinal axis of the gas turbine engine. The annular structure defines an annular channel and comprises a first density, according to various embodiments. The gas turbine engine may further include a weight-saving filler disposed within the annular channel. The weight-saving filler may have a second density that is less than the first density. The gas turbine engine may further include an annular retention strap disposed around the engine central longitudinal axis of the gas turbine engine. The annular retention strap is at least partially embedded in the weight-saving filler, according to various embodiments.

A seal system a ceramic component having a surface region defining a first surface roughness, a metallic component situated adjacent the surface region, and a coating system disposed on the surface region. The coating system includes a silicon-containing layer on the surface region and a barrier layer on the silicon-containing layer. The silicon-containing layer has a surface in contact with the barrier layer. The barrier layer has a surface in contact with the metallic component. The surface of the barrier layer has a second surface roughness that is less than the first surface roughness. The barrier layer limits interaction between silicon of the silicon-containing layer and elements of the metallic component. The barrier layer has a coefficient of thermal expansion that is within about 60% of a coefficient of thermal expansion of the ceramic component. A gas turbine engine and a method are also disclosed.