The present invention relates to gas turbine engines, and in particular, to collector boxes for industrial gas turbine engines.
Gas turbine engines typically include one or more compressor sections, a combustor section, and one or more turbine sections. Gas flows through such gas turbine engines along a main flow path from the compressor sections where the gas is compressed, through the combustor where the gas is mixed with fuel and combusted, and then through the turbine sections where power is extracted from the gas. In some gas turbine engines, gas compressed by the compressor section can be diverted or “bled” to a second path where it bypasses the combustor and/or the turbine sections. Air can be bled from a gas turbine engine for various operating conditions, such as to assist in starting the gas turbine engine or to assist in emergency stopping of the gas turbine engine.
According to the present invention, a gas turbine engine includes a turbine section, a compressor section, a bleed air collector box, and a v-band clamp. The compressor section is positioned upstream of the turbine section and includes a compressor case circumferentially surrounding the compressor section. The v-band clamp attaches the bleed air collector box to the compressor case.
Another embodiment is a gas turbine engine including a turbine section, a compressor section, a sheet metal duct, and first and second v-band clamps. The compressor section is positioned upstream of the turbine section. The compressor section includes a rotor, a compressor case circumferentially surrounding the rotor, and an intermediate case connected to and positioned downstream of the compressor case. The sheet metal duct circumferentially surrounds a portion of the compressor case and a portion of the intermediate case. The first v-band clamp attaches the sheet metal duct to the compressor case. The second v-band clamp attaches the sheet metal duct to the intermediate case.
Another embodiment is a method of attaching a bleed air collector box to a gas turbine engine. The method includes positioning a compressor case axially upstream of and adjacent to a bleed duct and positioning the bleed air collector box circumferentially around a portion of the compressor case and a portion of the bleed duct. The bleed air collector box is attached to the compressor case via a first v-band clamp. The bleed air collector box is attached to the bleed duct via a second v-band clamp.
As is known in the art of gas turbines, incoming ambient air 30 becomes pressurized air 32 in the low and high pressure compressor sections 16 and 18. Fuel mixes with pressurized air 32 in combustor section 20, where it is burned. Once burned, combustion gases 34 expand through high and low pressure turbine sections 22, 24 and through power turbine section 26. High and low pressure turbine sections 22 and 24 drive high and low pressure rotor shafts 36 and 38 respectively, which rotate in response to the combustion products and thus rotate the attached high and low pressure compressor sections 18, 16.
Intermediate case (IMC) 40 is positioned between low pressure compressor section 16 and high pressure compressor section 18. IMC 40 defines a flow path for pressurized air 32 between low pressure compressor section 16 and high pressure compressor section 18. IMC 40 also provides structural support for gas turbine engine 10.
IMC centerbody 44 includes a plurality of struts 50 connecting outer diameter (OD) case 52 to inner diameter (ID) case 54. In the illustrated embodiment, eight struts 50 transfer load between OD case 52 and ID case 54 to provide structural support for gas turbine engine 10. Struts 50, OD case 52, and ID case 54 combine to define a flow path between low pressure compressor section 16 and high pressure compressor section 18 (shown in
Collector box 46 is connected to bleed duct 42 for receiving bleed air that passes through bleed duct 42. In the illustrated embodiment, collector box 46 is a sheet metal duct including front wall 56, aft wall 58, side walls 60 and 62, and bottom wall 64. Front wall 56 and aft wall 58 are substantially flat, parallel walls, with front wall 56 positioned axially forward of aft wall 58. Side walls 60 and 62 are substantially flat, parallel walls positioned on opposite sides of gas turbine engine 10 (shown in
Collector box 46 is connected to rear flange 48 of bleed duct 42 via clamp 68. Clamp 68 is a v-band clamp (also called a v-retainer, Marman clamp, or Marmon clamp) including v-band 70 and latches 72 and 74. V-band 70 extends circumferentially around rear flange 48 to connect aft wall 58 of collector box 46 to rear flange 48. Latches 72 and 74 can tighten v-band 70 so as hold collector box 46 tight against rear flange 48. Latches 72 and 74 can include T-bolt latches, quick release latches, over-center latches, C-30 clip latches, T-bolt saddle latches, double trunnion hex-bolt latches, or other latches suitable for the application.
Pressurized air 32 also flows as bleed air in a substantially radial direction through bleed duct outlets 88 to collector box 46 (shown in
Front section 86 of bleed duct 42 connects to low pressure compressor case 76 (shown in
V-band 80 of clamp 78 includes center portion 94 positioned between side portions 96 and 98. V-band 80 has a section that is shaped as an upside down U or upside down V. V-band 80 covers flange 90 and connection portion 92 such that flange 90 and connection portion 92 are positioned axially between side portions 96 and 98 and radially inward of center portion 94. Latches 82 and 84 (shown in
V-band 70 of clamp 68 includes center portion 102 positioned between side portions 104 and 106. V-band 70 has a section that is shaped as an upside down U or upside down V. V-band 70 covers rear flange 48 and connection portion 100 such that rear flange 48 and connection portion 100 are positioned axially between side portions 104 and 106 and radially inward of center portion 102. Latches 72 and 74 (shown in
Clamps 68 and 78 can thus connect collector box 46 to bleed duct 42 and low pressure compressor case 76 of gas turbine engine 10. Clamps 68 and 78 can be relatively large, for example, having a diameter in excess of about 50 inches (about 1.27 meters). Because clamps 68 and 78 can be relatively large, collector box 46 can also be relatively large and can extend circumferentially around bleed duct 42 and low pressure compressor case 76. Using clamps 68 and 78 can reduce or eliminate the number of bolts and bolt holes needed to connect collector box 46 to gas turbine engine 10. Thus, attaching collector box 46 to gas turbine engine 10 via clamps 68 and 78 can reduce the cost of and the time to manufacture and assemble gas turbine engine 10.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims. For example, low pressure compressor section 16, intermediate case 40, and collector box 46 need not be shaped and configured precisely as illustrated, but could be modified as appropriate for a given application.
The following are non-exclusive descriptions of possible embodiments of the present invention.
A gas turbine engine can include a turbine section, a compressor section, a bleed air collector box, and a v-band clamp. The compressor section can be positioned upstream of the turbine section and include a compressor case circumferentially surrounding the compressor section. The v-band clamp can attach the bleed air collector box to the compressor case.
The gas turbine engine of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional components:
A gas turbine engine can include a turbine section, a compressor section, a sheet metal duct, and first and second v-band clamps. The compressor section can be positioned upstream of the turbine section. The compressor section can include a rotor, a compressor case circumferentially surrounding the rotor, and an intermediate case connected to and positioned downstream of the compressor case. The sheet metal duct can circumferentially surround a portion of the compressor case and a portion of the intermediate case. The first v-band clamp can attach the sheet metal duct to the compressor case. The second v-band clamp can attach the sheet metal duct to the intermediate case.
The gas turbine engine of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional components:
A method of attaching a bleed air collector box to a gas turbine engine can include positioning a compressor case axially upstream of and adjacent to a bleed duct and positioning the bleed air collector box circumferentially around a portion of the compressor case and a portion of the bleed duct. The bleed air collector box can be attached to the compressor case via a first v-band clamp. The bleed air collector box can be attached to the bleed duct via a second v-band clamp.
The method of the preceding paragraph can optionally include, additionally and/or alternatively any, one or more of the following features, configurations and/or additional steps: