DAMPER CLIP FOR A SERVICE TUBE
Publication Date: 2017-Mar-09
The IP.com Prior Art Database
In a gas turbine engine, a damper clip attached to a service tube provides mid span damping and also assists in moving natural frequencies out of the engine's operating range.
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DAMPER CLIP FOR A SERVICE TUBE
 In a gas turbine engine, a damper clip attached to a service tube provides mid span
damping and also assists in moving natural frequencies out of the engine's operating
 This disclosure relates generally to gas turbine engines and more particularly to
service tubes in such engines.
 A typical gas turbine engine includes one or more shafts which carry
turbomachinery blading which is enclosed by one or more stationary casings of the
 The shafts are mounted for rotation in several bearings, usually of the rolling-
element type. The bearings are enclosed in enclosures called "sumps" which are
pressurized and provided with an oil flow for lubrication and cooling.
 The engine is provided with several "service tubes" each of which is a pipe, tube,
or conduit generally extending from one of the sumps (or other interior engine
component) to one of the casings, in a generally radial direction.
 The service tubes may serve to transport fluids such as air, oil, fuel, or hydraulic
fluids within the engine. The service tubes may also serve as passageways or conduits for
structure such as electrical wires or actuating rods.
 One problem with service tubes is that they are generally of a relatively small
diameter with thin walls and extend over a relatively large axial length. In operation,
engine vibrations can excite one or more natural frequencies of the service tubes, leading
to cracking and failure.
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 Described herein are damper clips configured to stiffen service tubes and prevent
BRIEF DESCRIPTION OF THE DRAWINGS
 The concept may be best understood by reference to the following description
taken in conjunction with the accompanying drawing figures, in which:
 FIGS. 1A-1E illustrate several variations of a damper clip having a pair of legs or
wings configured in a U- or V-shape;
 FIGS. 2A-2F illustrate several variations of a damper clip having a pair of legs or
wings configured in a spiral shape;
 FIGS. 3A-3C illustrate several variations of a damper clip having a pair of clip
members secured to opposite sides of a service tube ;
 FIGS. 4A-4D illustrate several variations of a damper clip incorporating a
 FIGS. 5A and 5B illustrate a damper clip including pair of legs or wings with an
additional compression spring placed between them; and
 FIGS. 6A-6C illustrate a tube having two or more damper clips attached thereto,
each damper clip having a single leg configured in a spiral shape.
DETAILED DESCRIPTION OF THE CONCEPT
 Illustrated in FIG. 1A is a schematic representation of a strut and service tube
assembly suitable for inclusion in a gas turbine engine. The strut 10 has spaced-apart
sidewalls 12 defining a hollow interior space 14.
 A service tube 16 passes through the hollow interior space 14. The service tube 16
defines an internal bore 18 whi...