Shrouded gas burners and jets therefor

Claim 2

A shrouded burner including in combination a gas jet having a plurality of gas orifices lying on a common ellipse producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud having at least one wall, said at least one wall protecting the gas orifices from direct airflow and being shaped and dimensioned so that a given flame passes in close proximity to the peripheral edge thereof, said peripheral edge being contoured so that at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 3

A burner as claimed in claim 1 in which the walls of the shroud are generally elliptical.

Claim 4

A burner as claimed in claim 2 in which two sets of orifices are provided the longitudinal axes of the orifices in each set having a different common point of intersection on the longitudinal axis of the jet.

Claim 5

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud for protecting the gas orifices from direct airflow in which: two sets of orifices are provided which lie on a common ellipse and which have diameters of 0.010 inches to 0.015 inches, the longitudinal axis of each orifice of one of the sets lying at an angle of the order of 15* to 20* to the longitudinal axis of the jet, and the longitudinal axis of each orifice of the other of the sets lying at an angle of the order of 30* to 40* to the longitudinal axis of the jet and in which the walls of the shroud are generally elliptical, the shroud having an internal diameter around the jet of the order of 0.30 inches ( + or - 25 percent), an internal width at the top in the minor axis of the order of 0.45 inch ( + or - 25 percent), and an internal length at the top in the major axis of the order of 0.84 inch ( + or - 25 percent), the distance of the orifices below the highest point of the shroud being of the order of 0.40 inch ( + or - 25 percent), whereby a given flame passes in close proximity to the peripheral edge of the shroud, and whereby at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge, and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 6

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud for protecting the gas orifices from direct airflow in which: two sets of orifices are provided which lie on a common ellipse and which have diameters of 0.010 inches to 0.015 inches, the longitudinal axis of each orifice of one of the sets lying at an angle of the order of 15* to 20* to the longitudinal axis of the jet, and the longitudinal axis of each orifice of the other of the sets lying at an angle of the order of 30* to 40* to the longitudinal axis of the jet and in which the walls of the shroud are generally elliptical, the shroud having an internal diameter around the jet of the order of 0.30 inches ( + or - 25 percent), an internal width at the top in the minor axis of the order of 0.45 inch ( + or - 25 percent), and an internal length at the top in the major axis of the order of 0.84 inch ( + or - 25 percent), the distance of the orifices below the highest point of the shroud being of the order of 0.40 inch ( + or - 25 percent), whereby a given flame passes in close proximity to the peripheral edge of the shroud, and whereby at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge, and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 7

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud protecting the gas orifices from direct airflow in which: the orifices lie on a common circle and have diameters of the order of 0.013 inch ( + or - 25 percent), the angle between the longitudinal axis of adjacent orifices being of the order of 20* to 30* and that between the longitudinal axis of each orifice and the longitudinal axis of the jet being of the order of 10* to 45*, and in which the shroud is in the form of an inverted truncated cone the shroud having an internal diameter around the jet of the order of 0.30 inch ( + or - 25 percent) and an internal diameter at the top of the order of 0.55 inch ( + or - 25 percent), the distance of the orifices below the highest point of the shroud being of the order of 0.40 inch ( + or - 25 percent), whereby a given flame passes in close proximity to the peripheral edge of the shroud and whereby at the maximum dEsign gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 8

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud protecting the gas orifices from direct airflow in which: the orifices lie on a common circle and have diameters of the order of 0.013 inch ( + or - 25 percent), the angle between the longitudinal axis of adjacent orifices being of the order of 20* to 30* and that between the longitudinal axis of each orifice and the longitudinal axis of the jet being of the order of 10* to 45*, and in which the shroud is in the form of an inverted truncated cone the shroud having an internal diameter around the jet of the order of 0.30 inch ( + or - 25 percent) and an internal diameter at the top of the order of 0.55 inch ( + or - 25 percent), the distance of the orifices below the highest point of the shroud being of the order of 0.40 inch ( + or - 25 percent), whereby a given flame passes in close proximity to the peripheral edge of the shroud and whereby at the maximum dEsign gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 9

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a tubular shroud for protecting the gas orifices from direct airflow in which: the orifices lie in a common plane containing the longitudinal axis of the jet and have diameters of 0.0095 inch to 0.0145 inch ( + or - 25 percent), the angle between the longitudinal axis of adjacent orifices being of the order of 17*, and in which a pair of opposed walls of the shroud are substantially planar in configuration, the walls being parallel or slightly upwardly convergent with respect to the longitudinal plane containing the orifices, the maximum width of the mouth of the shroud being of the order of 0.312 inch ( + or - 25 percent), the length of the mouth being of the order of 1.077 inch to 1.100 inch ( + or - 25 percent), and the tip of the jet being of the order of 0.570 inch ( + or - 25 percent) below the uppermost point of the shroud, whereby a given flame passes in close proximity to the peripheral edge of the shroud and whereby at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 10

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a tubular shroud for protecting the gas orifices from direct airflow in which: the orifices lie in a common plane containing the longitudinal axis of the jet and have diameters of 0.0095 inch to 0.0145 inch ( + or - 25 percent), the angle between the longitudinal axis of adjacent orifices being of the order of 17*, and in which a pair of opposed walls of the shroud are substantially planar in configuration, the walls being parallel or slightly upwardly convergent with respect to the longitudinal plane containing the orifices, the maximum width of the mouth of the shroud being of the order of 0.312 inch ( + or - 25 percent), the length of the mouth being of the order of 1.077 inch to 1.100 inch ( + or - 25 percent), and the tip of the jet being of the order of 0.570 inch ( + or - 25 percent) below the uppermost point of the shroud, whereby a given flame passes in close proximity to the peripheral edge of the shroud and whereby at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 11

A shrouded burner as claimed in claim 6 in which: there are five orifices, the three inner orifices having a diameter of the order of 0.0125 inch ( + or - 25 percent) and the two outer orifices having a diameter of the order of 0.0095 inch ( + or - 25 percent).

Claim 12

A shrouded burner as claimed in claim 6 in which: there are five orifices, the three inner orifices having a diameter of the order of 0.0145 inch ( + or - 25 percent) and the two outer orifices having a diameter of the order of 0.0115 inch ( + or - 25 percent).

Claim 13

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud for protecting the gas orifices from direct airflow, in which: the orifices lie in a common plane containing the longitudinal axis of the jet and have diameters of the order of 0.0117 inch ( + or - 25 percent), the angle between the longitudinal axis of adjacent orifices being of the order of 18* and in which the shroud consists of two substantially semicircular substantially parallel walls of the order of 0.687 inch ( + or - 25 percent) radius and having a separation of the order of between 0.260 and 0.312 inch ( + or - 25 percent), whereby a given flame passes in close proximity to the peripheral edges of said walls and whereby at the maximum design gas pressure the point of divergence of adjacent flames is level with said edges and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 14

A shrouded burner for providing stable nonaerated flames with natural gas at operating pressures of approximately 6 to 10 inches water gauge including in combination a gas jet having a plurality of gas orifices producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud for protecting the gas orifices from direct airflow, in which: the orifices lie in a common plane containing the longitudinal axis of the jet and have diameters of the order of 0.0117 inch ( + or - 25 percent), the angle between the longitudinal axis of adjacent orifices being of the order of 18* and in which the shroud consists of two substantially semicircular substantially parallel walls of the order of 0.687 inch ( + or - 25 percent) radius and having a separation of the order of between 0.260 and 0.312 inch ( + or - 25 percent), whereby a given flame passes in close proximity to the peripheral edges of said walls and whereby at the maximum design gas pressure the point of divergence of adjacent flames is level with said edges and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 15

A shrouded burner as claimed in claim 9 in which: the walls are closed at the bottom by a pair of flat plates which project from the jet at an angle of about 10* below the horizontal.

Claim 16

A shrouded burner including in combination a gas jet having a cylindrical wall surmounted by a frustum of a cone, a plurality of gas orifices being formed in the conical surface and being arranged parallel to the longitudinal axis of the jet so as to produce, in use, diverging flames whiCh coalesce only in the region of the gas orifices, and a shroud having at least one wall, said at least one wall protecting the gas orifices from direct airflow and being shaped and dimensioned so that a given flame passes in close proximity to the peripheral edge thereof, said peripheral edge being contoured so that at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 17

A shrouded burner including in combination a gas jet having a cylindrical wall surmounted by a frustum of a cone, a plurality of gas orifices being formed in the conical surface and being arranged parallel to the longitudinal axis of the jet so as to produce, in use, diverging flames whiCh coalesce only in the region of the gas orifices, and a shroud having at least one wall, said at least one wall protecting the gas orifices from direct airflow and being shaped and dimensioned so that a given flame passes in close proximity to the peripheral edge thereof, said peripheral edge being contoured so that at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 18

A shrouded burner including in combination a gas jet having a plurality of gas orifices lying in a common plane containing the longitudinal axis of the jet and producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud having at least one wall, said at least one wall protecting the gas orifices from direct airflow and being shaped and dimensioned so that a given flame passes in close proximity to the peripheral edge thereof, said peripheral edge being contoured so that at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 19

A shrouded burner including in combination a gas jet having a plurality of gas orifices lying in a common plane containing the longitudinal axis of the jet and producing, in use, diverging flames which coalesce only in the region of the gas orifices, and a shroud having at least one wall, said at least one wall protecting the gas orifices from direct airflow and being shaped and dimensioned so that a given flame passes in close proximity to the peripheral edge thereof, said peripheral edge being contoured so that at the maximum design gas pressure the point of divergence of adjacent flames is level with said edge and at minimum design gas pressure the point of divergence of adjacent flames is slightly below said edge.

Claim 20

A burner as claimed in claim 12 in which saId shroud has a pair of opposed walls, said walls being substantially planar in configuration and being parallel or slightly upwardly convergent with respect to the longitudinal plane containing the orifices.

Claim 21

A burner as claimed in claim 12 in which the shroud consists of two substantially semicircular plane walls, said walls being parallel or slightly upwardly convergent with respect to the longitudinal plane containing the orifices.

Claim 22

A burner as claimed in claim 14 in which the walls are closed at the bottom by a pair of flat plates.