JPS60233410A - Burner plate body - Google Patents

Abstract

PURPOSE:To prevent an irregular red heating and prevent a surface temperature from being increased excessively by a method wherein a plurality of rhombic or rectangular projections are arranged in the surface of the burner plate with a die formation process and flame holes passing through the front and rear surfaces are arranged at the substantial central parts of the trough and projection of the outer circumferences of the projections, silica film is formed on the surface of the plate. CONSTITUTION:A plurality of rhombic or rectangular projections 8 are formed on the surface of a burner plate 7 which is composed of a composite heat-resistant ceramic with a heat- resistant clay mainly consisting of a alumina-silica fiber with die forming process, flame holes 9 and 10 passing through the front and rear surfaces are arranged at the substantial central part of the trough and projection at the outer circumference of the projection and then a silica film 11 is formed on the surface of the burner plate 7. Mixture injected from the flame holes 9 performs a surface combustion near the outlets of the flame holes 9 to form a stable flame holding without any disturbance of combustion gas at the projected part and lift while holding hot temperature, the projected part 8 is heated from its circumference to show a red heat. The mixture from the flame hole 10 performs a surface combustion near the outlet of the flame hole 10 to heat the central part of the projection 8. In this way, the projection 8 is heated concentrically from both its outer circumference part and the central part, resulting in that a fast raising of red heat can be made and a hot temperature of the surface part can be assured.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an infrared burner, particularly a burner plate body, which is mainly made of heat-resistant ceramic and is used in a gas combustor.

Structure of the conventional example and its problems Conventionally, the burner plate body used in this type of infrared burner has a plurality of V-Vs which cross each other in the horizontal and vertical directions on the surface of the burner plate 1, as shown in FIGS. 1 and 2. It has a structure in which a protrusion 2 is formed by providing a groove, and a plurality of flame holes 3 are provided at the bottom of the outer periphery of the protrusion 2.

In the combustion process as a burner, fuel gas from the nozzle 4 is ejected into the mixing tube 6 and reaches the mixing chamber 6. At this time, surface combustion occurs near the outlet of the flame hole 3 of the burner plate 1, mainly at the protrusion 2. becomes red hot.

The problems with this configuration are l) Since the protrusion 2 is not provided with the flame hole 3, the red heat of the protrusion 2 is indirectly received by the surface combustion heat of the flame hole 3 provided at the bottom of the outer periphery of the protrusion 2. 41) The protrusion 2 does not have a flame hole 3, so the red-hot temperature of the protrusion 2 is as low as 850 to 900°C, making it impossible to obtain high radiation as an infrared burner.411) The protrusion 2 does not have a flame hole 3,
Moreover, since the overall number of flame holes is small, the pressure loss when the fuel gas passes through the three flame holes of the burner plate becomes large. This causes a shortage of air intake from the vicinity of the nozzle 4, - The amount of carbon oxide generated increases and the flame length increases (60 to 80 wx), making it impossible to construct the equipment compactly.

In addition, as another conventional example, a plurality of triangular or rectangular protrusions are formed on the surface of a burner plate mainly made of heat-resistant clay, and within these protrusions, flame holes with the same diameter as the flame holes provided at the bottom of the outer periphery of the protrusions are used. Some have three or four flame holes. In this configuration, since a plurality of flame holes penetrate through the protrusion, the red-hot surface area decreases and the radiation intensity decreases, and the protrusion is exposed to high temperatures (900
When the plate surface becomes red-hot to a high temperature (e.g. 950 °C or higher), the red heat flows backwards into the plate with city gas, which has a high thermal conductivity and a fast combustion rate, and the plate surface temperature rises, causing a backfire phenomenon. 1050°C), making it difficult to provide a high-temperature radiant burner.

Other known radiation burners include metallic burners that burn fuel gas on the surface of metal gold and steel.

Metallic burners have the advantage of being easy to process and have a short time to reach red-hot temperature after ignition, but they have poor corrosion resistance at high temperatures and it is practically impossible to expect high radiation by raising the surface temperature. was there.

Purpose of the Invention The present invention solves the conventional problems, and aims to prevent red heat unevenness and increase the surface temperature (for example, 950 to 1050
An object of the present invention is to provide a burner plate body for a high-radiation burner that achieves rapid rise in red heat and achieves cc).

Structure of the Invention The present invention provides a plurality of diamond-shaped or rectangular protrusions formed by molding on the surface of a burner plate made of heat-resistant ceramic mainly composed of alumina-siliceous fibers, and troughs and protrusions on the outer periphery of the protrusions. A flame hole is provided approximately in the center of the plate, penetrating both sides, and a silica coating is formed on the plate surface.

With this configuration, it is possible to eliminate uneven red heat by making the shape of the protrusion uniform, and to increase the red heat temperature (for example, 1000 to 1050).
oC), as well as a rapid rise in red heat (e.g. 750
°C (approximately 30 seconds) to obtain a high radiation burner.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on FIGS. 3 to 6.

7 is a burner plate made of a composite ceramic plate of alumina-siliceous clay and heat-resistant fibrous ceramic;
The plate has a thermal conductivity smaller than 0.1 u/mh-'b, and one side of the bottom is 3-4 sow on the surface.
A diamond-shaped protrusion 8 having a continuous fin height of 1.0 to 1.6 fins and having a partially flattened upper surface is formed by dehydration molding using a mold. A flame hole 9 is provided at the bottom of the outer periphery of the diamond-shaped protrusion 8, and a flame hole 9 is provided at the bottom of the outer periphery at approximately the center of the protrusion 8.

The flame hole diameters of flame holes 9 and 10 are smaller than those of propane gas plates, since in city gas plates where the combustion speed is fast, the combustion interface runs to the back side through the flame holes and causes a backfire phenomenon. Also, when propane gas is used as fuel, there is less occurrence of flashback, so the flame hole diameter is 1.
．． It is provided at 3 to 1.4+w. 11 is a silica film formed on the surface of the burner plate 7, which is sprayed with an inorganic mixture of silica sol or heated at a high temperature (800 to 10
A silica film 11 is formed by baking at 00°C.

In the above structure, the heat-resistant ceramic plate thus obtained is assembled into a burner metal frame consisting of a mixing chamber equipped with a mixing tube similar to that shown in FIG. Gas pressure city gas (6C)
When it is ejected from a nozzle and ignited and burned on the surface of the ceramic plate, the surface temperature of the protrusion increases to 1000-1050℃.
Burns stably without causing backfire even when heated to a certain degree,
Uniform red heat with no red heat unevenness was obtained, and the surface temperature was approximately 160 to 2000 C higher than that of the conventional Shpank burner, and an increase in radiation efficiency was observed.

That is, the air-fuel mixture ejected from the flame hole 9 provided in the trough on the outer periphery of the protrusion 8 undergoes surface combustion near the outlet of the flame hole 9, and the turbulence of the combustion gas at the protrusion and high temperature maintenance result in stable combustion without lift. A stable flame is formed, and the protrusion 8 is heated from the surrounding area and becomes red hot. Furthermore, the air-fuel mixture from the flame hole 10 provided approximately at the center of the protrusion 8 performs surface combustion near the outlet of the flame hole 10, thereby heating the center portion of the protrusion 8. In this way, the protrusion 8 is heated intensively from both the outer periphery and the center, so that the red heat rises quickly and the surface temperature is high (1000 to 1050 cc).
) was secured.

Furthermore, the protrusions 8 are formed by adding a coagulant (for example, a Na o H solution and a starch solution) to a suspension of ceramic raw material powder and coagulating it in water, followed by dehydration in a mold while stirring. Since the height of the protrusion is set by molding, the height of the protrusion is set to a high value in advance (for example, 2 to 3 baits), and after dehydration molding, it is fired at a high temperature, and the height of the protrusion is adjusted to a predetermined height using a grinder. (approx. 1.0 m)
Compared to the conventional method of grinding, the height and shape of the protrusions 8 are made more uniform. As a result, when the protrusion 8 is heated by the surface combustion flames on the outer periphery and the center, it will be uniformly red-hot without unevenness (for example, the temperature unevenness on the plate surface will be 1S°C).
The following) were secured. Furthermore, since the height of the protrusion 8 is set by dehydration molding using a mold, secondary grinding of the protrusion is unnecessary, the number of processing steps can be reduced, and an inexpensive burner plate can be provided.

Furthermore, a silica film 11 is formed on the surface of the burner plate 7 to increase the thermal conductivity on the plate surface and promote heat transfer with the combustion gas, thereby suppressing local abnormal heating at the protrusion 8 and producing uniform red heat. and a surface temperature of 70 to 8
It has the effect of raising the temperature by 0°C, as shown in Figure 7 (1000 to 1
A high temperature of 0.50 oc was ensured.

In addition, in combination with the concentrated heating of the protrusion 8, the red-hot rise time can be greatly shortened (for example, to about 30 seconds to reach 750 cc), and a burner with high heating speed can be provided.

Furthermore, similar effects were confirmed for propane gas burner plates.

Effects of the Invention As described above, the present invention provides a plurality of diamond-shaped or rectangular protrusions by molding on the surface of a burner plate made of heat-resistant ceramic mainly composed of alumina-siliceous fibers. A large number of flame holes are provided at the bottom of the outer periphery and inside the protrusions, and a silica film is formed on the plate surface. Burner can be provided.

■ We can provide a radiant burner that quickly rises to red heat and has excellent heating properties.

(Grinding of the three protrusions is no longer necessary, and by reducing the number of processing steps, an inexpensive burner plate can be obtained.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a conventional burner plate body.Figure 2a
, b are a sectional view and a plan view of the burner plate body, and FIG. 3 is a plan view showing an embodiment of the burner plate body of the present invention.
Fig. 4 is a sectional view of the burner plate body, Fig. 5 is a plan view of the main part of the flame hole of the burner plate body, Fig. 6 is a sectional view of the main part of the flame hole, and Fig. 7 is a plate temperature characteristic diagram. shows. 7...Burner plate, 8...Protrusion, 9...
...Flame hole 10...Flame hole, 11...
・Silica film. Name of agent: Patent attorney Toshio Nakao and one other person Figure 1 Figure 2 Figure 3 Figure 5

Claims (1)

[Claims] A plurality of diamond-shaped or rectangular protrusions are formed by molding on the surface of a burner plate made of composite heat-resistant ceramic with fireclay mainly composed of alumina and siliceous fibers, and these protrusions have outer troughs and protrusions. A burner plate body provided with a flame hole penetrating both the front and back sides in an approximately central portion, and a silica coating formed on the surface of the burner plate.