JPH0311582Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention opens the main burner located on the central axis of the combustion tube into the combustion tube, which is provided concentrically at radial intervals within the radiant tube. The present invention relates to a radiant tube burner in which a pilot burner consisting of a mixed gas passage tube extending parallel to the main burner and a nozzle at the tip of the pilot burner similarly opens into a combustion tube.

[Conventional technology]

Generally, the nozzle of a gas burner serving as a main burner is placed concentrically in a combustion tube provided concentrically within a radiant tube, and the fuel gas ejected from the gas burner is passed between the gas burner and the combustion tube. A radiant tube burner is known in which primary combustion is performed by primary air supplied through an annular space between the combustion tube and the radiant tube, and secondary combustion is performed by secondary air supplied through an annular space between the combustion tube and the radiant tube. However,
The pilot burner used in such radiant tube burners usually burns inside a closed radiant tube, so the flame blows out due to pressure fluctuations, etc., and the pilot burner becomes useless. Because of this, it was necessary to create a combustion rate that would not be affected by pressure fluctuations, etc., and the flame was stabilized by burning 5,000 to 10,000 Kcal/h of gas.

[The problem that the idea attempts to solve]

The object of the present invention is to stabilize the flame of a pilot burner and reduce the amount of combustion of this burner.

[Means to solve the problem]

Therefore, according to the present invention, a flame stabilizing tube is provided which extends coaxially from the tip of the nozzle of the pilot burner and opens at the tip. Form an opening.

[Effect of idea]

Thus, according to the present invention, the mixed gas of air and fuel supplied through the mixed gas passage tube of the pilot burner is ignited at the nozzle to generate a flame, but this flame immediately flows from the nozzle into the combustion tube. Instead of being injected, the flame is ejected from the opening at the tip of the tube into the combustion tube only after passing through the flame-stabilizing tube, so even if the pressure inside the closed radiant tube fluctuates, the flame emitted from the nozzle remains within the flame-stabilizing tube. It will be maintained and will not disappear. Furthermore, the flame-holding cylinder is kept heated by the soft small flames emitted from the numerous openings distributed on the surrounding wall, which improves flame stability due to the flame-holding cylinder being maintained at a high temperature. do. In this way, the flame of the pilot burner is stabilized without being blown out even by pressure fluctuations within the radiant tube, so the amount of combustion of the pilot burner can be lowered than in the past. Since the flame is dispersed and exits not only from the opening at the tip of the flame stabilizing tube but also from a large number of openings in the peripheral wall, local heating of the combustion tube is also prevented. A large number of openings in the peripheral wall of the flame-stabilizing tube create diffusion turbulence inside the flame-stabilizing tube, which also stabilizes the flame. Incidentally, since the flow velocity of the flame ejected from the tip opening of the flame stabilizing cylinder can also be reduced to a flow velocity comparable to the flame propagation velocity, flame stabilization properties are improved.

〔Example〕

In FIG. 1, a gas burner 1 as a main burner has a distributed multi-nozzle 3 protruding into a combustion tube 2 provided concentrically around the burner 1, and a gas supply pipe at the rear end of the burner. At the rear of the combustion tube 2, a primary air supply tube 5 that similarly concentrically surrounds the burner is continuously formed, and four primary air inlets 6 are connected to the combustion tube 2 over the periphery thereof. is drilled there. Further, on the tip of the gas burner 1, a primary air swirling vane 7 having an angle of 15 to 60 degrees is fixed via a holding tube 8, and a radiant tube is attached to the outer periphery of the combustion tube 2 and the primary air supply tube 5. 9 are provided concentrically, the primary air supply tube and the radiant tube are closed at an end wall 12 via respective flanges 10 and 11, and the gas burner 1 extends rearward through the end wall. . An air supply pipe 13 is connected to the rear of the radiant tube 9, and air from here is fed to the primary air supply pipe 5 via the inlet 6.

Further, as shown in FIG. 2, the pilot burner 20 according to the present invention includes a flame stabilizing tube 22 formed by distributing a large number of openings 21 in the combustion tube 2 on the peripheral wall, and a gas nozzle. 23 and a mixed gas passage cylinder 24 are coaxially connected, a mixed gas supply member 25 is connected to the rear of the mixed gas passage cylinder, and a spark plug 26 is connected to the rear end of this mixed gas supply member. Mounted, the electrode 27 extends coaxially with the burner, and the entire burner is supported via the end wall 12 and the swirl vanes 7.

[Effect]

Now, the mixed gas of fuel gas and air supplied from the mixed gas supply member 25 is transferred to the mixed gas passage cylinder 2.
4 and is ejected from the gas nozzle 23, and this ejected gas generates a spark between the gas nozzle 23 and the electrode 27 by an ignition plug by appropriately operating an ignition device (not shown), and ignites the flame-holding tube 22. A soft flame 28 is ejected from the opening 21 (FIGS. 3 and 4), forming a stable flame with a low combustion amount and no blowout. This is achieved by heating the flame stabilizing tube 22 with a group of small flames ejected from a large number of openings 21 provided in the flame stabilizing tube 22, thereby stabilizing the flame. This prevents the flame from blowing out by setting it to about the flame propagation speed.

The pilot burner according to the present invention has a flame-holding cylinder at the tip, which allows for a low combustion rate.
1000 ~ 10000 Kcal/h combustion amount
The low combustion rate of 5000Kcal/h creates a stable flame that will not blow out, and the radiant tube and burner are placed inside the combustion tube to prevent local heating, so there is no deformation of the radiant tube and burner. It has become possible to increase the lifespan to a value that can withstand long-term use.

[Brief explanation of drawings]

FIG. 1 is an axial cross-sectional view of a radiant tube burner equipped with a pilot burner according to the present invention;
Fig. 2 is a vertical sectional view of the pilot burner, and Fig.
4 are a front view and a side view showing the combustion state by the pilot burner. 1... Main burner, 2... Combustion tube, 9... Radiant tube, 20... Pilot burner,
21...Opening, 22...Flame stabilizing tube, 23...Nozzle, 24...Mixed gas passage tube.

Claims (1)

[Scope of utility model registration request] The main burner 1 located on the central axis of the combustion tube 2 is opened into the combustion tube 2 provided concentrically at radial intervals in the radiant tube 9, and the mixed gas passage tube 2 extends parallel to the main burner 1.
In a radiant tube burner in which a pilot burner 20 consisting of a pilot burner 4 and a nozzle 23 at its tip is similarly opened to the combustion tube 2, a radiant tube burner further extends coaxially from the tip of the nozzle 23 of the pilot burner 20 to the nozzle 23 at the tip. A radiant tube burner characterized in that an open flame-holding tube 22 is provided, and a large number of small flame openings 21 are formed distributed on the peripheral wall of the flame-holding tube 22.