Floating air seal for a turbo machine

• US 8,215,645 B1
• Filed: 05/17/2010
• Issued: 07/10/2012
• Est. Priority Date: 05/17/2010
• Status: Active Grant

• Current Assignee: Florida Turbine Technologies, Inc. (Kratos Defense & Security Solutions Incorporated)
• Original Assignee: Florida Turbine Technologies, Inc. (Kratos Defense & Security Solutions Incorporated)
• Inventors: Aho, Wilho V Jr.
• Primary Examiner(s): Patel, Vishal
• Application Number:
  US12/781,327
• Time in Patent Office: 785 Days
• Field of Search: 277/370, 277/399, 277/401, 277/408
• US Class Current: 277/370
• CPC Class Codes: F16J 15/342 with means for feeding fluid directly to the face
• CPC Class Codes: F16J 15/441 with floating ring
• CPC Class Codes: F16J 15/46 with packing ring expanded or pressed into place by fluid pressure, e.g. inflatable packings connection of valves to inflatable elastic bodies B60C29/00; for sealing arrangements in vehicles B60J10/244; for sealing arrangements of openings in buildings E06B7/2318; for tube connections F16L

Abstract

A floating air seal to seal a lower pressure chamber from a higher pressure chamber and allow for both axial and radial shifting of the rotor with respect to the stator while maintaining the sealing capability. The floating seal includes an annular piston that slides within an annular groove formed within the stator in an axial direction with an annular flange secured to it that forms an annular manifold between the piston and the flange. The annular piston includes a plurality of feed holes that open into the annular manifold, and the annular flange includes a plurality of baffle holes that open into the annular manifold but offset from the feed holes so that Helmholtz excitations of the rotor disk do not occur. The baffle holes open into an outer annular groove that forms an air cushion against the rotor disk surface due to the air flow.

Claims

1. A floating seal comprising:

a rotor having a floating seal forming surface substantially perpendicular to a rotating axis of the rotor;

a stationary stator located adjacent to the rotor;

an annular groove formed within the stator and opening toward the floating seal forming surface of the rotor;

an annular floating piston axially movable within the annular groove of the stator;

the annular floating piston having an annular flange with an annular groove formed on the rotor side;

the annular piston having a plurality of feed holes opening into an annular manifold formed between the annular piston and the annular flange;

the annular flange having a plurality of baffle holes passing through and opening into the annular manifold;

the feed holes being offset from the baffle holes in order to reduce a Helmholtz excitation from an air flow through the feed holes and the baffle holes;

two of the baffle holes are used for each one of the feed holes;

the annular floating piston having a fluid pressure reacting surface on an opposite side to the annular groove; and

,

the annular floating piston having a fluid passage connecting the fluid pressure reacting surface to the annular groove to supply a fluid pressure and form a fluid cushion for the floating seal.

2. The floating seal of claim 1, and further comprising:

the annular piston is a composite annular piston with an acrylic annular piston having an aluminum annular flange secured to the annular piston.