Ning Fang

Bio: Ning Fang is an academic researcher from General Electric. The author has contributed to research in topics: Shroud & Seal (mechanical). The author has an hindex of 7, co-authored 10 publications receiving 249 citations.

Supplemental seal for the chordal hinge seals in a gas turbine

Abstract: In a gas turbine having a chordal hinge seal between an inner rail of each nozzle segment and an annular axially facing sealing surface of a nozzle support ring, a supplemental seal is disposed between the support ring and inner bands of the nozzle segments on a lower pressure side of the chordal hinge seals. To minimize or prevent leakage flow across the chordal hinge seals, a generally U-shaped supplemental seal having reversely folded U-shaped marginal portions is received in a cavity formed in the axially extending sealing surface of the inner rail of the nozzle segment. At operating conditions, the marginal portions seal against the base of the cavity and the annular sealing surface of the nozzle support ring to prevent leakage flow past the chordal hinge seal from entering the hot gas path. To install the supplemental seal, the seal is first compressed and maintained in a compressed state by applying one or more wraps about the supplemental seal or an epoxy to secure the seal when compressed in the cavity. At operating temperatures, the retention means releases the seal to engage marginal portions against opposite sealing surfaces of the nozzle segment and support ring.

Seal for gas turbine nozzle and shroud interface

Abstract: In a gas turbine including a nozzle retaining ring having a first annular axially sealing surface and a shroud segment having an axial registering second surface. To minimize or prevent leakage flow between the retaining ring and shroud segments, a generally U-shaped seal having reversely folded U-shaped marginal portions is received in a cavity formed in the second surface. At operating conditions, the marginal portions seal against the base of the cavity and the first surface of the retaining ring to prevent leakage flow past the retaining ring/shroud segment interface. To install the seal, the seal body is first compressed and maintained in a compressed state by applying one or more wraps about the seal body and an epoxy is used to secure the seal when compressed in the cavity. At operating temperatures, the retention means releases the seal to engage marginal portions against opposite sealing surfaces of the shroud segments and retaining ring.

Cloth seal for an inner compressor discharge case and methods of locating the seal in situ

Abstract: Upper and lower halves of the inner barrel of a compressor for a turbine are bolted to one another along a horizontal midline joint with metal-to-metal surface contact. Elongated grooves are provided in the engaging surfaces, with the upper groove having a depth greater than the depth of the lower groove. Elongated seals are provided in the grooves, including an elongated shim with a metallic woven covering on opposite sides, and margins having sealing edges. The depth of the seal is equal to or less than the depth of the upper groove and an adherent material maintains the seal in the upper groove during installation. In operation, the adherent material dissolves at temperatures above ambient and the seal drops by gravity to bear against the walls of the grooves in response to high pressure air leaking through any gap at the horizontal midline joint.

A composite tubular woven seal for an inner compressor discharge case

Abstract: Upper and lower halves of the inner barrel of a compressor for a turbine are bolted to one another along a horizontal midline joint with metal-to-metal surface contact. Elongated grooves are provided in the margin of one of the barrel halves. Elongated composite tubular woven seals are provided in the grooves, the seals having a diameter in excess of the depth of the grooves. The seals comprise an inner woven metal core surrounded by an annular silica fiber layer, in turn surrounded by a metal foil with an outer protective covering of a braided stainless steel. Upon joining the upper and lower halves, the compliant seal is crushed within the groove, maintaining a seal between the barrel halves in the event of warpage of the compressor casing during turbine operation.

Composite tubular woven seal for gas turbine nozzle and shroud interface

Abstract: A compliant woven tubular seal is provided in an arcuate cavity opening through an axial face of a plurality of shroud segments in opposition to a nozzle retaining ring. The annular composite tubular woven compliant seal includes a stainless steel inner metal core surrounded by an annular layer of silica fiber. Surrounding the silica fiber is a metal foil which prevents flow past the supplemental seal. An outer wear-resistant braiding serves as a protective covering and wear surface.

Modified fc molecules

Abstract: Disclosed is a process for preparing a pharmacologically active compound, in which at least one internal conjugation site of an Fc domain sequence is selected that is amenable to conjugation of an additional functional moiety by a defined conjugation chemistry through the side chain of an amino acid residue at the conjugation site. An appropriate amino acid residue for conjugation may be present in a native Fc domain at the conjugation site or may be added by insertion (i.e., between amino acids in the native Fc domain) or by replacement (i.e., removing amino acids and substituting different amino acids). In the latter case, the number of amino acids added need not correspond to the number of amino acids removed from the previously existing Fc domain. This technology may be used to produce useful compositions of matter and pharmaceutical compositions containing them. A DNA encoding the inventive composition of matter, an expression vector containing the DNA, and a host cell containing the expression vector are also disclosed.

Supplemental seal for the chordal hinge seals in a gas turbine

Abstract: In a gas turbine having a chordal hinge seal between an inner rail of each nozzle segment and an annular axially facing sealing surface of a nozzle support ring, a supplemental seal is disposed between the support ring and inner bands of the nozzle segments on a lower pressure side of the chordal hinge seals. To minimize or prevent leakage flow across the chordal hinge seals, a generally U-shaped supplemental seal having reversely folded U-shaped marginal portions is received in a cavity formed in the axially extending sealing surface of the inner rail of the nozzle segment. At operating conditions, the marginal portions seal against the base of the cavity and the annular sealing surface of the nozzle support ring to prevent leakage flow past the chordal hinge seal from entering the hot gas path. To install the supplemental seal, the seal is first compressed and maintained in a compressed state by applying one or more wraps about the supplemental seal or an epoxy to secure the seal when compressed in the cavity. At operating temperatures, the retention means releases the seal to engage marginal portions against opposite sealing surfaces of the nozzle segment and support ring.

Low-ductility open channel turbine shroud

Abstract: A turbine shroud apparatus for a gas turbine engine includes: a plurality of arcuate shroud segments arranged as an annular shroud, each of the shroud segments comprising low-ductility material and having a cross-sectional shape defined by opposed forward and aft walls, and opposed inner and outer walls, the walls extending between opposed first and second end faces, wherein an open channel is formed through the outer wall of each shroud segment; an annular stationary structure surrounding the shroud segments; and a hanger received in the open channel of each shroud segment and mechanically coupled to the stationary structure, each of the hangers passing through the respective open channel and including an enlarged portion having greater cross-sectional area than the open channel, the enlarged portion engaging the outer wall of the respective shroud segment, so as to retain the shroud segment radially relative to the stationary structure.

System for sealing an inner retainer segment and support ring in a gas turbine and methods therefor

Abstract: Arcuate seal layers conforming with one another are disposed between inner retainer segments and inner rails of nozzle segments of a gas turbine. The layers are secured to the aft axial face of the segments and project radially outwardly to seal against the forward axial faces of the rails. The rear axial faces of the rails have chordal seals for sealing against the forward axial faces of the support rings. The seal layers have radial cuts misaligned with one another in an axial direction to preclude leakage flows through gaps formed by the cuts. Arcuate spacers are staggered circumferentially with the arcuate retainer segments whereby an intermediate pressure plenum is formed between the finger seals and chordal seals.

Low leakage finger seal

Abstract: A seal (26) for an exhaust duct (18) includes a metal mesh member (32) sandwiched between an outer plate (28) and an inner plate (30). The seal (26) includes a plurality of flexible members (34) defined by a plurality of slots (42, 44) in both the inner and outer plates (28, 30). The flexible members (34) provide for expansion and contraction along with creating flexibility in the region of contact between a seal land (36) and the seal (26). The metal mesh member (32) substantially eliminates gaps and leak paths created through the slots (42, 44). The metal mesh member (32) is composed of a plurality of interwoven wire strands (50) impregnated with a high temperature elastomeric sealant. The impregnation of high temperature elastomeric sealant over the metal mesh member (32) improves sealing while maintaining the desired flexibility of the seal (26).