JPS63180356A - Production of gasifying type combustor - Google Patents

Abstract

PURPOSE:To simply produce a gasifying type combustor, which is possible to use at high temp., by casting sheath heater in a casting space of metallic mold having the casting space of burner structural body for the combustor at the time of producing the gasifying type combustor for liquid fuel by casting a cast iron. CONSTITUTION:At the time of producing the burner structural body 1 having a passage of air for gasifying fuel combustion at the center part and a gasifying room 4 heating and gasifying the liquid fuel, such as petroleum, at both sides, as the casting of cast iron, electric insulating material 6, such as MgO, is packed into an iron pipe 5, in which a heating wire 7 is inserted through, as the sheath heater 3 for heating the gasifying room 4, and it is cast in the bottom part 2 of the burner structural body 1 at the same time of casting the burner structural body 1, to integrate with the body 1. By conducting the power to the heating wire 7, to heat it, the gasifying room 4 is heated by its heat, and the liquid fuel passing through in it is heated and gasified under good thermal efficiency, to burn by air from the center passage in the burner structural body 1.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a method for manufacturing a cast iron vaporization combustor that vaporizes liquid fuel such as petroleum, mixes it with combustion air, and burns it. .

[Prior Art] As shown in FIG. 3, a vaporizing combustor that has been widely used in conventional heating devices, for example, has a vaporizing chamber 4 around the outer circumference of a cylindrical combustion air passage formed in the center. The burner structure 17 has a bottomed container structure and is equipped with a sheathed heater 3 that heats the burner structure 17 and promotes vaporization of fuel. The burner structure 17 is made of cast iron, which has excellent heat resistance and durability, and is integrally molded by casting.

The sheathed heater 3 has a structure in which a heating wire 7 is inserted through an iron vibrator 5 through magnesia.The outer shell is made of iron and has a melting point close to that of cast iron, and since it is an electric component, a burner structure is used to avoid damage. It is later assembled into 17.

That is, a ring-shaped groove 18 for embedding the sheathed heater 3 is formed in the bottom of the burner structure 17. has been done.

[Problems to be Solved by the Invention] The conventional vaporization type combustor described above incorporates the sheathed heater 3 into the groove 18 at the bottom of the burner structure 17, and integrates it into the burner structure 17 with one copper braze. It requires many manufacturing steps and requires copper brazing19
Even if the burner structure 17 is made of cast iron, its use at high temperatures is limited.

The present invention has been made in order to solve these conventional problems, and therefore, an object of the present invention is to provide a highly reliable manufacturing method for a vaporizing combustor that does not cause problems in high-temperature use, requires fewer manufacturing steps, and can reduce costs. The purpose is to

[Means for Solving the Problems] The method for manufacturing a vaporizing combustor according to the present invention includes installing a sheathed heater in a main part of a casting space of a mold having a casting space corresponding to the shape of a burner structure. The molten cast iron is held in a floating state by a heater holding structure formed in the mold, and the molten cast iron is heated to a predetermined temperature while monitoring the position of the connection terminal pulled out of the held sheathed heater mold and the mold. It is poured into the casting space.

[Function] In this invention, since the sheathed heater is embedded in the cast iron burner structure together with casting, there is no need for a process or structure for fixing the sheathed heater, and a vaporization type combustor that can withstand high-temperature use is obtained. It is easy to determine the position of the sheathed heater in the casting space, and it is easy to detect positional deviation of the sheathed heater in the casting space.

[Example] FIG. 1 shows a vaporizing combustor obtained by a manufacturing method as an example of the present invention.

The characteristic of this vaporization type combustor is that a sheathed heater 3 is cast into the bottom part 2 of the burner structure 1 made of cast iron, which heats the burner structure 1 and promotes vaporization of the supplied liquid fuel. It is almost completely buried, leaving only the connection end to the external circuit.

The burner structure l has a bottomed container structure having a vaporization chamber 4 around the outer circumference of a cylindrical combustion air passage formed in the center,
The wall thickness of the bottom part 2 of the burner structure 1 in the part where the sheathed heater 3 is cast is about 61 mm. The sheathed heater 3 has a structure in which an iron pipe 5 (carbon steel) is filled with magnesia 6 which has electrical insulation properties, and a heating wire 7 is inserted into it, except for the connection end with an external circuit and about three exposed parts 8. is completely embedded in the bottom part 2 of the burner structure 1 and is connected and integral with the burner structure 1. A 100V AC power source is applied to the sheathed heater 3 from an external circuit, and the burner structure 1 is
It is heated to about 0°C to promote vaporization of the fuel in the vaporization chamber 4. This vaporization type combustor does not have any particular peculiarities in the combustion operation itself, but the sheathed heater 3 is integrated by casting, and the copper soldering does not have any fixed structure, so there are restrictions on high-temperature use. It has a feature that it is much looser than the conventional one and can be used within the temperature range that the burner structure 1 can withstand. Furthermore, since the outer surface of the sheathed heater 3 is in close contact with the burner structure 1 almost entirely, resistance to heat conduction is small and heating performance is good.

This air/heat type combustor is obtained by casting the sheathed heater 3 together with the burner structure 1, but the outer shell of the sheathed heater 3 is made of iron and its melting point is close to that of the iron casting.
Moreover, since it is an electrical component, it cannot be used as a handcart to avoid damage due to impacts during casting, but as shown in Figure 2, it has a casting hole E9 corresponding to the shape of the burner structure 1. A split mold 10 divided into a fixed side and a movable side is made of a material such as a copper alloy with good heat dissipation.
A runner part 1 to the main part in the casting space 9 of
The sheathed heater 3 is supported in a floating state by touching two holding protrusions 12 that protrude into the casting space 9 of the split mold 10, avoiding the entrance of the sheathed heater 3. While monitoring the positional relationship between the connection terminal 13 and the mold 1o with a sensing device 14 whose electrical resistance changes depending on the state of contact between the two,
Mold 10 is made by splitting molten cast iron whose temperature is controlled at ~1380°C.
It can be manufactured by pouring into the casting space 9 from the sprue 15. The sheathed heater 3 is held in the casting space 9 by using a mold structure of the holding protrusion 12 and the connecting end pull-out part.
The relative positional relationship between the connecting terminal 13 and the mold 10 is stabilized by narrowing down the clearance Q to a level of 111, and the reliability is increased by monitoring with the sensing device 14.In other words, if the sheathed heater 3 becomes misaligned, the relative positional relationship between the connecting terminal 13 and the mold 10 will be changed. changes, so the positional shift of the internal sheathed heater 3 can be detected from the outside.

What should be noted in the above manufacturing method is that the pouring temperature is 1320°.
The mold should be designed so that the flow rate of the molten cast iron poured from the sprue 15 from the runner part 11 to the outer periphery of the sheathed heater 3 is smaller than the flow velocity of the runner part 11. The temperature of the mold is controlled within a certain range by the forced cooling means 16 so that the temperature of the hot water decreases to about 100°C by the time the hot water reaches the gas vent at the top of the casting space 9. The purpose is to ensure that the sheathed heater 3 is held within the casting space 9, and that its position in the casting space 9 is not shifted. Carbon and ions in molten cast iron are quantified and controlled at a predetermined ratio. Further, since the pouring temperature is the main cause of damage or destruction of the sheathed heater 3, strict control is required. The forced cooling means 16 for cooling the split mold 10 conducts a liquid refrigerant to the split mold 10, and controls the temperature by controlling the flow rate.

As a result, a vaporizing combustor having a sheathed heater cast therein can be obtained, and according to this manufacturing method, the manufacturing process of the vaporizing combustor can be significantly reduced compared to the conventional method.

In other words, there is no need to assemble the sheathed heater 3, there is no need for brazing, and it is possible to obtain a vaporization type combustor that is superior in terms of functionality, and since there is no problem with the casting position of the sheathed heater 3, it is possible to reduce the number of defective products. It is difficult to produce and reduces manufacturing costs.

[Effects of the Invention] As is clear from the above description of the embodiments, the method for manufacturing a vaporizing combustor of the present invention has a method for producing a vaporizing combustor in which the main part in the casting space of a mold having a casting space corresponding to the shape of the burner structure is The sheathed heater is held in a floating state by a heater holding structure formed in the mold, and the temperature is controlled to a predetermined temperature by monitoring the position of the connection terminal pulled out of the held sheathed heater mold and the positional relationship with the mold. Since the molten cast iron is poured into the casting space of the mold, the sheathed heater can be embedded in the burner structure of the iron casting along with the casting, and there is no need for a process or structure for fixing the sheathed heater, and it is a vaporizer that can withstand high-temperature use. In addition to obtaining a type combustor, it is easy to determine the position of the sheathed heater in the casting space, and the positional deviation of the sheathed heater in the casting space can be easily detected, eliminating defects in the casting position of the sheathed heater and reducing costs. .

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the configuration of a vaporizing combustor obtained by a manufacturing method according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing an embodiment of the manufacturing method of the present invention, and FIG. 3 is a conventional In Figure 0, which is a cross-sectional view of an example vaporizing combustor, 1 is a burner structure, 2 is a bottom, 3 is a sheathed heater, 9 is a casting space,
10 is a split mold, 12 is a holding protrusion, 13 is a connecting terminal, 1
4 is a sensing device, and 16 is a forced cooling means. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (2)

[Claims] (1) When casting a vaporizing combustor, a sheathed heater that heats the burner structure and promotes vaporization of the supplied liquid fuel is embedded in the bottom of the burner structure made of iron casting. A sheathed heater is held in a floating state by a heater holding structure formed in the mold in a main part of the casting space of a mold having a casting space corresponding to the shape of the structure, and the held sheathed heater is pulled out of the mold. A method for manufacturing a vaporizing combustor, characterized by pouring molten cast iron whose temperature is controlled to a predetermined temperature into a casting space of a mold while monitoring the positional relationship between the connection terminal and the mold. (2) A method for manufacturing a vaporization type combustor according to claim 1, characterized in that an increase in concentration due to mold casting is suppressed within a certain range by forced cooling means.