Boiler tube insert and boiler tubes having inserts
Boiler systems having convection sections containing a set of boiler tubes having boiler tube inserts, boiler tubes for use in the convection section of a boiler system, and boiler tube inserts for boiler tubes for use in the convection section of a boiler system are provided herein. The boiler tube inserts are positioned in a first section of each boiler tube, where the first section extends from a front tube end the receives combustion gases from a furnace. The first section of the boiler tubes can be a plain tube section, and the boiler tubes can have a second section that includes a finned structure. The boiler tube inserts can be helical and can be made of a ceramic material.
1 . A boiler system comprising:
a housing;
a furnace within the housing, the furnace including a rear wall; and
a set of boiler tubes in a convection section of the boiler system;
wherein each boiler tube of the set of boiler tubes includes a front tube end that receives combustion gases from the furnace, a rear tube end at which the combustion gases exit the boiler tube, a first section that extends from the front tube end along at least a portion of a length of the boiler tube, and a second section that extends from the first section to the rear tube end;
wherein the first section of each boiler tube of the set of boiler tubes includes a boiler tube insert that includes a central core that extends along an entire length of the boiler tube insert, and a plurality of projections that each helically wrap around the central core in less than a full 360° arc.
2 . The boiler system of claim 1 , wherein each boiler tube of the set of boiler tubes is straight.
3 . The boiler system of claim 1 , wherein the first section of each boiler tube of the set of boiler tubes is a plain tube section.
4 . The boiler system of claim 1 , wherein the boiler tube insert is positioned in a front portion of the first section, wherein the front portion starts at the front tube end and extends along at least a portion of a length of the first section.
5 . The boiler system of claim 4 , wherein the front portion is up to about half of the length of the first section.
6 . The boiler system of claim 1 , wherein each boiler tube includes at least one indentation configured to retain the boiler tube insert within the boiler tube.
7 . The boiler system of claim 1 , wherein the boiler tube insert comprises:
a solid central core;
wherein the boiler tube insert is made of a ceramic material.
8 . The boiler system of claim 7 , wherein:
the plurality of projections consists of a from two projections to six projections;
each of the plurality of projections helically wraps around the solid central core in an arc that is from about 135° to about 225°; and
a length of the boiler tube insert is from about 1 inches to about 20 inches.
9 . A boiler tube configured to be used in a convection section of a boiler system, the boiler tube comprising:
a front tube end configured to receive combustion gases from a furnace;
a rear tube end configured to allow the combustion gases to exit the boiler tube; and
a first section that extends from the front tube end along at least a portion of a length of the boiler tube and a second section that extends from the first section to the rear tube end, wherein the first section includes a boiler tube insert that includes a central core that extends along an entire length of the boiler tube insert, and a plurality of projections that each helically wrap around the central core in less than a full 360° arc.
10 . The boiler tube of claim 9 , wherein the boiler tube is straight.
11 . The boiler tube of claim 9 , wherein the first section of the boiler tube is a plain tube section.
12 . The boiler tube of claim 9 , wherein the boiler tube insert is positioned in a front portion of the first section, wherein the front portion starts at the front tube end and extends along at least a portion of a length of the first section.
13 . The boiler tube of claim 12 , wherein the front portion is up to about half of the length of the first section.
14 . The boiler tube of claim 9 , wherein the boiler tube includes at least one indentation configured to retain the boiler tube insert within the boiler tube.
15 . The boiler tube of claim 9 , wherein the boiler tube insert comprises:
a solid central core;
wherein the boiler tube insert is made of a ceramic material.
16 . The boiler tube of claim 15 , wherein:
the plurality of projections consists of from two projections to six projections;
each of the plurality of projections helically wraps around the solid central core in a rotation that is from about 135° to about 225°; and
the length of the boiler tube insert is from about 1 inches to about 20 inches.
17 . A boiler system comprising:
a housing;
a furnace within the housing, the furnace including a rear wall; and
a set of boiler tubes in a convection section of the boiler system;
wherein each boiler tube of the set of boiler tubes includes a front tube end that receives combustion gases from the furnace, a rear tube end at which the combustion gases exit the boiler tube, and a first section that extends from the front tube end along at least a portion of a length of the boiler tube;
wherein the first section of each boiler tube of the set of boiler tubes includes a boiler tube insert that includes a central core that extends along an entire length of the boiler tube insert, and a plurality of projections that each helically wrap around the central core in less than a full 360° arc; and
wherein each boiler tube includes at least one indentation configured to retain the boiler tube insert within the boiler tube.
18 . The boiler system of claim 17 , wherein the boiler tube insert is positioned in a front portion of the first section of each boiler tube of the set of boiler tubes, wherein the front portion starts at the front tube end and extends along at least a portion of a length of the first section.
19 . A boiler tube configured to be used in a convection section of a boiler system, the boiler tube comprising:
a front tube end configured to receive combustion gases from a furnace;
a rear tube end configured to allow the combustion gases to exit the boiler tube; and
a first section that extends from the front tube end along at least a portion of a length of the boiler tube, wherein the first section includes a boiler tube insert that includes a central core that extends along an entire length of the boiler tube insert, and a plurality of projections that each helically wrap around the central core in less than a full 360° arc;
wherein the boiler tube includes at least one indentation configured to retain the boiler tube insert within the boiler tube.
20 . The boiler tube of claim 19 , wherein the boiler tube insert is positioned in a front portion of the first section, wherein the front portion starts at the front tube end and extends along at least a portion of a length of the first section.