Method and apparatus to provide sealing contact between first and second fueldraulic components

According to one aspect, an apparatus to provide sealing contact between first and second fueldraulic components includes a metallic member, wherein the metallic member comprises a layer of metal that is formed into a spring energized seal member. The apparatus also includes a layer disposed on an outer portion of the metallic member to provide sealing contact between the first and second fueldraulic components.

BACKGROUND OF THE INVENTION

The subject matter disclosed herein relates to sealing components and, more particularly, sealing fueldraulic aerospace components.

Fueldraulic components are hydraulic parts that utilize fuel as the working fluid for an application. Aerospace fueldraulic components may be exposed to extreme conditions, such as elevated temperatures, that may affect component operation or performance. In particular, fueldraulic components should be designed to withstand and operate during and after exposure to elevated temperatures, such as those associated with a fuel fire. Fire protection parts such as fire shields, fire blankets and intumescent fire paints may be added to components to help withstand fire exposure. In some cases, these fire protection parts add undesired weight, complexity, unwanted materials and cost to assemblies in aerospace applications.

BRIEF DESCRIPTION OF THE INVENTION

According to one aspect of the invention, an apparatus to provide sealing contact between first and second fueldraulic components includes a metallic member, wherein the metallic member comprises a layer of metal that is formed into a spring energized seal member. The apparatus also includes a layer disposed on an outer portion of the metallic member to provide sealing contact between the first and second fueldraulic components.

According to another aspect of the invention, a method for sealing fluid flow between first and second fueldraulic components includes placing a seal member in a gland of the first fueldraulic component and placing the second fueldraulic component on the first fueldraulic component, thereby compressing the seal member to form sealing contact with the first and second fueldraulic components, wherein the seal member comprises a layer of metal formed into spring energized metallic member and a polymeric layer disposed on an outer portion of the metallic member.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1is a perspective view of a portion of an exemplary fueldraulic assembly100. In the depicted example, the fueldraulic assembly100is part of a gas turbine engine system, such as a gas turbine for aerospace applications. Of course, the fueldraulic assembly100could be utilized in other turbine systems used for other applications. The illustrated fueldraulic assembly100includes a seal member102to be placed between a first fueldraulic component104and a second fueldraulic component106. The first fueldraulic component104includes a gland108to receive at least a portion of the seal member102, wherein the seal member102is configured to seal fluid flow (e.g., jet fuel) through a first passage110in the first fueldraulic component104into a second passage118in the second fueldraulic component106. In an embodiment, the seal member102includes a metallic member112that is formed into a spring energized shape. The spring energized shape of the metallic member112may be any suitable geometry to provide sealing contact between components when compressed along an axis120. As depicted, the seal member102is a ring or circular member that includes a passage116for flow of fluid between the first and second fueldraulic components104,106. The seal member102also includes a layer114disposed on an outer surface of the metallic member112. In an embodiment, the layer114is a polymeric layer configured to flex and deform to provide sealing contact to surfaces of the first and second fueldraulic components104,106. Further, the layer114flexes as the metallic member112is axially compressed when placed between two components or parts. As depicted, the exemplary layer114is disposed on portions of the outer surface of the metallic member112that contact the components. In other embodiments, the layer114is disposed on substantially the entire outer surface of the metallic member112. The metallic member112includes any suitable durable and strong metal alloy, such as stainless steel or a steel alloy. The seal member102is spring energized causing the seal member102to compress from an expanded shape when axially compressed and to expand back to the expanded shape when released.

As used herein, “downstream” and “upstream” are terms that indicate a direction relative to the flow of working fluid through the apparatus. As such, the term “downstream” refers to a direction that generally corresponds to the direction of the flow of working fluid, and the term “upstream” generally refers to the direction that is opposite of the direction of flow of working fluid. The term “radial” refers to movement or position perpendicular to an axis or center line. It may be useful to describe parts that are at differing radial positions with regard to an axis. In this case, if a first component resides closer to the axis than a second component, it may be stated herein that the first component is “radially inward” of the second component. If, on the other hand, the first component resides further from the axis than the second component, it may be stated herein that the first component is “radially outward” or “outboard” of the second component. The term “axial” refers to movement or position parallel to an axis. Further, the term “circumferential” refers to movement or position around an axis. In addition, the term “seal” refers to the action of or a part configured to join adjacent systems or mechanisms by reducing or preventing leakage of a fluid, containing pressure and/or excluding contamination.

FIG. 2is a sectional perspective view of the seal member102show inFIG. 1. The seal member102includes the metallic member112formed into a spring energized shape. Spring energized shapes may be described as a shape that deforms when compressed (e.g., axially compressed) while still exerting a force that resists the compression and which, when the compressive force is released, returns to substantially the pre-compression shape. From time to time herein, a member that has a spring energized shape may be referred to as a spring energized member. The exemplary spring energized shape includes a C-shaped cross section. Other spring energized shapes may include a toroid (i.e., O-shaped cross section), U-shaped cross section, V-shaped cross section or other suitable geometry to provide the spring energized feature. A layer114is disposed on the outer surface of the metallic member to provide sealing contact to adjacent components. The exemplary layer114is disposed on outer surface of the metallic member112, wherein the layer114on outer surface is configured to contact adjacent component surfaces. In an embodiment, a region200of the layer114provides sealing contact with the first fueldraulic component104while a region201of the layer114provides sealing contact with the second fueldraulic component106. The depicted layer114is formed from a polymeric material. In other embodiments, the layer114is formed from any suitable conforming and durable material to reduce fluid flow across the layer114when in sealing contact with adjacent surfaces. The polymeric material of the layer114provides sealing contact with the fueldraulic components104and106for a selected temperature range. In a case when the seal member102is exposed to a fire and corresponding elevated temperatures, the polymer material of layer114melts or burns off. After the layer114is melted, a region202of the metallic member112provides sealing contact with the first fueldraulic component104while a region203of the metallic member112provides sealing contact with the second fueldraulic component106.

Accordingly, the seal member102provides sealing contact via the layer114disposed on the metallic member during normal operation (i.e., operation without elevated temperatures and/or fires). In case of a fire or elevated temperatures that cause the layer114to melt and/or burn, the metallic member112of the seal member102provide sealing contact to adjacent surfaces of components. The sealing contact provided by the layer114may substantially restrict all or significant amount of fluid communication between the inner passage116and a region outside the seal member102. In addition, sealing contact may also maintain a desired pressure differential across the seal member102. In an embodiment, the metallic member112provides sealing contact with adjacent surfaces that restrict fluid communication between the inner passage116and a region outside the seal member102. Further, in an example, the sealing contact provided by the metallic member112may be less restrictive than the sealing contact provided by the layer114, due to deformation of the material of layer114. In one embodiment, the layer114provides sealing contact to surfaces of adjacent components up to about 600 degrees Fahrenheit or 315 degrees Celsius (e.g., elevated temperatures associated with burning fuel). The layer114may enable sealing contact in temperatures ranging from about −65 to about 600 degrees F. or about −53 to about 315 degrees C. At temperatures greater than about 600 degrees F. (315 degrees C.), the layer114burns and the metallic member112provides sealing contact to surfaces of adjacent components, such as fueldraulic components104and106. Therefore, the seal member102enables safe operation and durability for fueldraulic systems in elevated temperature environments.

FIG. 3is a sectional perspective view of an exemplary seal member300. The seal member300includes a metallic member302formed into a spring energized shape. The exemplary spring energized shape may be described as a toroid or as including an O-shaped cross section. A layer304is disposed on the entire outer surface of the metallic member302to provide sealing contact to adjacent components. In an embodiment, the layer304comprises a polymeric material that provides sealing contact with the fueldraulic components (e.g.,104,106) for a selected temperature range. In a case when the seal member300is exposed to a fire and corresponding elevated temperatures, the polymer material of layer304melts and/or burns off the metallic member302. After the layer304is burned or melted from the metallic member302, the spring energized shape of the metallic member302provides sealing contact between fueldraulic components, thereby reducing fluid leaking across the seal member300to maintain pressure differentials and fluid flow.

The exemplary layer114,304is formed from a suitable material, such as polymer and/or elastomer, which is adhered or bonded to the metallic member112,302. Examples of suitable organic polymers are thermoplastic polymers, thermosetting polymers, blends of thermoplastic polymers, blends of thermosetting polymers, and blends of thermoplastic polymers with thermosetting polymers. The organic polymer can be a homopolymer, a copolymer, a block copolymer, an alternating copolymer, an alternating block copolymer, a random copolymer, a random block copolymer, a graft copolymer, a star block copolymer, an ionomer, a dendrimer, or a combination comprising at least one of the foregoing polymers. An exemplary polymer for the member is a thermoplastic polymer.