Fuel fitting

Abstract

A fuel fitting assembly includes a monolithic fuel fitting formed by additive manufacturing. The fitting includes a first end, a second end, a conduit extending axially through the fitting from the first end to the second end, and a first sealing element. The first end is to be connected to a fuel line. The second end is to be connected to a device requiring or providing fuel. The first sealing element includes a sealing seat circumferentially surrounding the conduit at the second end of the fitting. The fuel fitting is integrally formed as a stack of layers of material.

1 . A method for manufacturing a monolithic fuel fitting comprises:
 building the fuel fitting by a layer-by-layer additive manufacturing process;   forming, while building the fitting, a first end, a second end opposite the first end, and a conduit extending axially through the fitting from the first end to the second end; and   integrally forming a first sealing element including a sealing seat circumferentially surrounding the conduit at the second end of the fitting.   
     
     
         2 . The method of  claim 1 , further including integrally forming a second sealing element, the second sealing element including a thinner portion of a fuel fitting wall such that when the fuel fitting is under axial compression, the thinner portion bulges radially outward. 
     
     
         3 . The method of  claim 1 , further including integrally forming a second sealing element, the second sealing element including an O-ring channel, the channel extending circumferentially around an exterior of the fitting. 
     
     
         4 . The method of  claim 3 , wherein the O-ring channel has a semi-circle shape in circumferential cross-section. 
     
     
         5 . The method of  claim 1 , wherein a width of the conduit varies along a length of the conduit to change fluid flow velocity along the length of the conduit. 
     
     
         6 . The method of  claim 1 , wherein additively manufacturing comprises using laser powder deposition. 
     
     
         7 . The method of  claim 1 , wherein additively manufacturing comprises using direct metal laser sintering. 
     
     
         8 . A fuel fitting assembly comprising:
 a monolithic fuel fitting formed by additive manufacturing, the fitting including:
 a first end to be connected to a fuel line; 
 a second end to be connected to a device requiring or providing fuel; 
 a conduit extending axially through the fitting from the first end to the second end; and 
 a first sealing element, the first sealing element including a sealing seat circumferentially surrounding the conduit at the second end of the fitting; 
 wherein the fuel fitting is integrally formed as a stack of layers of material. 
   
     
     
         9 . The assembly of  claim 8 , wherein the fitting further comprises a second sealing element, wherein the second sealing element includes a thin-walled portion of the fitting circumferentially surrounding the conduit, such that the thin-walled portion bows radially outward when the fitting is place under axial compression. 
     
     
         10 . The assembly of  claim 9 , further comprising:
 a tube nut, the tube nut including nut threads;   a cylindrical wall circumferentially surrounding an opening in the device through which fuel is to pass, the cylindrical wall projecting from the device, and including device threads for engaging the nut threads; and   the fitting further includes a flange radially projecting radially outward from the fitting,   wherein the fitting is placed under axial compression by engagement between the nut threads and the device threads to force the tube nut against the flange; the axial compression forcing the sealing seat into contact with the device to form a first seal, and forcing the thin-walled portion into contact with the cylindrical wall to form a second seal.   
     
     
         11 . The assembly of  claim 8 , wherein the fitting further comprises a second sealing element, wherein the second sealing element includes an O-ring channel, the channel extending circumferentially around an exterior of the fitting. 
     
     
         12 . The assembly of  claim 11 , wherein the O-ring channel has a semi-circle shape in circumferential cross-section. 
     
     
         13 . The assembly of  claim 11 , further comprising:
 an O-ring partially contained by the O-ring channel;   a cylindrical wall circumferentially surrounding an opening in the device through which fuel is to pass, the cylindrical wall projecting from the device, and including device threads; and   the fitting further includes fitting threads for engaging the device threads;   wherein engagement between the fitting threads and the device threads forces the sealing seat into contact with the device to form a first seal, and forces the O-ring into contact with the cylindrical wall to form a second seal.   
     
     
         14 . The assembly of  claim 8 , wherein the fitting is made of a sintered metal. 
     
     
         15 . The assembly of  claim 8 , wherein the fitting is made of a nickel alloy. 
     
     
         16 . The assembly of  claim 8 , wherein a width of the conduit decreases along a length of the conduit to increase fluid flow velocity within the conduit along the length of the conduit. 
     
     
         17 . The assembly of  claim 8 , wherein a width of the conduit increases along a length of the conduit to decrease fluid flow velocity within the conduit along the length of the conduit.