Extended orifice for a premixed burner

Abstract

An extended orifice for a premixed burner system is provided, comprising: an inlet section configured to couple to a fuel supply line, the inlet section including an inlet opening; a central body; an outlet section configured to couple to a manifold of a burner tube, the outlet section including a metering orifice; a central bore extending through the inlet section, the central body and the outlet section between the inlet opening and the metering orifice; and an extended tube extending from the outlet section, the extended tube having a tube wall that defines a bore, the bore extending between the metering orifice and an outlet opening at a distal end of the extended tube.

What is claimed is: 
     
         1 . An extended orifice for a premixed burner system, comprising:
 an inlet section configured to couple to a fuel supply line, the inlet section including an inlet opening;   a central body;   an outlet section configured to couple to a manifold of a burner tube, the outlet section including a metering orifice;   a central bore extending through the inlet section, the central body and the outlet section between the inlet opening and the metering orifice; and   an extended tube extending from the outlet section, the extended tube having a tube wall that defines a bore, the bore extending between the metering orifice and an outlet opening at a distal end of the extended tube.   
     
     
         2 . The extended orifice of  claim 1 , wherein the extended tube has a length such that the outlet opening at the distal end is positioned adjacent a central longitudinal axis of the burner tube when the extended orifice is coupled to the manifold of the burner tube. 
     
     
         3 . The extended orifice of  claim 1 , wherein the inlet section includes external threads configured to mate with internal threads of the manifold. 
     
     
         4 . The extended orifice of  claim 1 , wherein the inlet section includes a conical surface extending between the inlet opening and the central bore. 
     
     
         5 . The extended orifice of  claim 3 , wherein the conical surface defines a radial cross-section that decreases with distance from the inlet opening. 
     
     
         6 . The extended orifice of  claim 1 , wherein the bore of the extended tube has a substantially circular radial diameter. 
     
     
         7 . The extended orifice of  claim 1 , wherein a radial diameter of the bore of the extended tube is greater than a radial diameter of the metering orifice. 
     
     
         8 . An extended orifice for a premixed burner system, comprising:
 an orifice having an inlet section configured to mate with a fuel supply line, an outlet section having an exit opening, and a metering orifice between the inlet section and the outlet section; and   an extended orifice adapter, comprising:
 a head having an orifice opening configured to receive the outlet section of the orifice; 
 a threaded end configured to mate with a manifold of a burner tube and a delivery opening in flow communication with the orifice opening; and 
 an extended tube defining a cylindrical bore extending between an inlet opening at a proximal end of the extended tube and an outlet opening at a distal end of the extended tube, the inlet opening being in flow communication with the delivery opening of the threaded end. 
   
     
     
         9 . The extended orifice of  claim 8 , wherein the extended orifice adapter further comprises a disk having a central opening, the disk being coupled to an outer end of the threaded end and the central opening being coupled to the proximal end of the extended tube such that the cylindrical bore is in flow communication with the central opening. 
     
     
         10 . The extended orifice of  claim 9 , wherein the disk is welded to the outer end and the proximal end of the extended tube is welded to the central opening of the disk. 
     
     
         11 . The extended orifice of  claim 8 , wherein the threaded end of the extended orifice adapter includes external threads configured to mate with internal threads of the manifold. 
     
     
         12 . The extended orifice of  claim 8 , wherein the head includes internal threads configured to mate with external threads on the outlet section of the orifice. 
     
     
         13 . The extended orifice of  claim 8 , wherein the extended tube has a length such that the outlet opening at the distal end is positioned adjacent a central longitudinal axis of the burner tube when the extended orifice is coupled to the manifold of the burner tube. 
     
     
         14 . The extended orifice of  claim 8 , wherein the head includes a plurality of faces configured to accommodate a wrench to tighten the extended orifice adapter into the manifold. 
     
     
         15 . A premixed burner system, comprising:
 a burner tube including a tube wall defining a flow bore and a manifold having an orifice opening and a fuel opening in flow communication with the flow bore; and   an extended orifice, comprising:
 an inlet section configured to couple to a fuel supply line, the inlet section including an inlet opening; 
 an outlet section configured to couple to the manifold of the burner tube, the outlet section including a metering orifice; 
 a central bore extending through the inlet section and the outlet section between the inlet opening and the metering orifice; and 
 an extended tube extending from the outlet section, the extended tube having a tube wall that defines a bore, the bore extending between the metering orifice and an outlet opening at a distal end of the extended tube; 
   wherein, when the extended orifice is coupled to the manifold of the burner tube, the outlet opening of the extended tube is positioned adjacent a central longitudinal axis of the burner tube to deliver fuel from the extended orifice into an oxidizer flow through the burner tube at a location adjacent the central longitudinal axis of the burner tube.   
     
     
         16 . The premixed burner system of  claim 15 , wherein the bore of the extended tube has a radial diameter that is greater than a radial diameter of the metering orifice. 
     
     
         17 . The premixed burner system of  claim 15 , wherein a longitudinal axis of the extended orifice is substantially perpendicular to the central longitudinal axis of the burner tube. 
     
     
         18 . The premixed burner system of  claim 15 , wherein the bore of the extended tube has a substantially circular radial cross-section. 
     
     
         19 . The premixed burner system of  claim 15 , wherein a longitudinal axis of the extended orifice forms an acute angle with the central longitudinal axis of the burner tube. 
     
     
         20 . The premixed burner system of  claim 15 , wherein a longitudinal axis of the extended orifice is one of above or below the central longitudinal axis of the burner tube. 
     
     
         21 . The premixed burner system of  claim 15 , wherein the extended tube has a length that is based upon an expected oxidizer flow rate and an expected fuel flow rate.