JPH0256590B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an apparatus for purging residual gas in a conduit and performing air purging after completion of the work, which is necessary during gas work.

(Prior art) Conventionally, in order to eliminate accumulated gas before construction work, for example, as shown in Fig. 3, a combustor E such as a general stove is connected to one side of a conduit D in the construction area. Connect an inert gas cylinder F such as nitrogen gas to the other side, and use the pressure of the nitrogen gas to send the remaining gas in the conduit D to the combustor E and burn it, and then purge this nitrogen gas etc. with air. This is done by method.

Furthermore, after the construction is completed, the air is purged with nitrogen gas, etc., and then the nitrogen gas is purged with gas.

However, in such conventional purging methods, the residual gas and air in the gas pipe are once replaced with an inert gas such as nitrogen, and then the nitrogen is replaced with air and gas again. Nitrogen gas or the like is required, and it takes time and effort to purge the gas and air in the conduit with nitrogen. Also, since nitrogen is used, measures must be taken to prevent oxygen deficiency in basements and the like.

Furthermore, since the above method involves burning residual gas and gas in a general combustor such as a stove, there is a problem in that harmful gases that cannot be burned are emitted.

(Problem to be Solved by the Invention) The problem to be solved by the present invention is to forcefully combust residual gas and gas in the conduit by introducing it into a combustor that is burning using another fuel. At the same time, the combustion air exhaust is used to suck out residual gas and other gases.

(Means for Solving the Problems) The technical means taken by the present invention to solve the above problems consists of a forced combustion piping system and a purge piping system, and the forced combustion piping system is composed of a forced combustion piping system and a purge piping system. The purge piping system is equipped with a combustion burner, a forced combustion fuel pipe that connects a fuel gas cylinder to the burner, and a forced combustion air pipe that is connected to this fuel pipe via a ventilary mixer, and the purge piping system is for burning the purge gas. It is equipped with a burner, a purge gas pipe connecting the burner and the conduit, and a purge gas combustion air pipe connected to the middle part of the purge gas pipe via a ventilator mixer, and the combustion gas is forced into the purge gas combustion burner. It is disposed close to the forced combustion burner so that it is discharged into the combustion atmosphere of the combustion burner.

(Function) According to the above-mentioned technical means of the present invention, the residual gas and gases in the conduit are sucked from the conduit into the purge piping system by the eject effect caused by flowing combustion air through the purge piping system, and the gas is absorbed into the purge piping system. It flows to a combustion burner and is burned there. When the concentration of the remaining gas drops to a level where it cannot be combusted, it is released from the purge gas combustion burner, but this unburned combustible gas is completely destroyed by the flame burning in a separate forced combustion burner. Burn.

(Example) Hereinafter, an example of the present invention will be described based on the drawings.

The purge machine is constructed by compactly incorporating a forced combustion piping system A and a purge piping system B together with a forcing panel G into a machine frame H.

Forced combustion piping system A is a forced combustion burner
A ₁ , a forced combustion fuel pipe A ₂ that supplies fuel gas to the burner A ₁ , and a forced combustion air pipe A ₃ that supplies combustion air _.
A ₃ is connected to the forced combustion piping system A midway through the ventilate mixer 1.

The forced combustion fuel pipe A ₂ is provided with a solenoid valve 3 and a zero governor 5 for flow rate adjustment, and the forced combustion air pipe A ₃ is provided with a blower 7 at the pipe base as a combustion air supply source, and at the midway point. A governor 8 and a butterfly valve 9 are provided.

The purge piping system B includes a burner B ₁ for burning purge gas, a purge gas piping B ₂ that guides residual gas or gas in the conduit D to the burner B ₁ , and an air piping B ₂ for burning purge gas that supplies combustion air. The above-mentioned both pipes B ₂ and B ₃ are the purge piping system B
Communication is made via a ventilator mixer 2 in the middle of the process. Air piping for combustion of the above purge gas B ₃
is the forced combustion air piping of the forced combustion piping system A.
A ₃ and the air supply source, that is, the blower 7, are the same,
It is installed by branching from forced combustion air piping _A3 .

In this purge piping system B, flashback preventers 12 and 13 are connected to burners for burning purge gas to prevent backfire.
It is double installed in front of B ₁ .

The flashback preventers 12 and 13 are screen burners 1
2 and a flame arrester 13, with the former located on the downstream side.

The purge gas piping B ₂ and the purge gas combustion air piping B ₃ are connected to the forced combustion fuel piping A ₂ of the forced combustion piping system A, and the forced combustion air piping A ₃ as well as the solenoid valve 4 and zero governor 6 of the former B. ₂ , a governor 8 and a butterfly valve 10 are installed in the latter _B3 . In addition, governor 8 is air piping for forced combustion.
Shared with _A3 .

On the other hand, the forced combustion burner A ₁ and the purge gas combustion burner B ₁ are incorporated into one combustion cylinder 11 as an integrated burner.

The combustion cylinder 11 has a vertical cylinder part 1 whose axis is substantially vertical.
1a, and an inclined cylindrical part 11b whose axis is inclined at a required angle and which connects to the vertical cylindrical part 11a in an upwardly slanted shape.The vertical cylindrical part 11a has a forced combustion burner _A1 , inclined cylinder part 1
A burner B ₁ for combusting purge gas and a screen burner constituting the flashback preventer 12 are provided in 1b, respectively. At this time, burner A ₁ for forced combustion
is arranged at a position where the flame is formed at the connecting portion between the vertical cylinder part 11a and the inclined cylinder part 11b. Further, at the upper part of the combustion tube 11, a double-cylindrical protection tube 18 for preventing burns is provided surrounding the opening of the vertical tube portion 11a, with a heat shield plate 18 on the inside and a punching metal 18b on the outside.

The forced combustion burner A ₁ and the purge gas combustion burner B ₁ each consist of a straight flame burner.

In the figure, 14 is a spark rod for igniting the forced combustion burner _A1 , and 15 is a flame rod for flame detection.

Further, 16 and 17 are flame detectors that detect backfire flames, and when these detect backfire, they shut off solenoid valve 4 of purge gas pipe B ₂ and send only air to extinguish the flame. be.

Such a purge machine is mounted on a truck or automobile, and is connected to the forced combustion fuel piping of the forced combustion piping system A.
Propane gas cylinder C is connected to A ₂ , and purge gas piping B ₂ of purge piping system B is connected to conduit D for use, and its operation is activated by turning on an operation switch (not shown) installed at an appropriate location. , control panel G
automatically controlled.

When the operation switch is turned on, the blower 7 starts operating and the solenoid valves 3 and 4 open.
A spark is generated in the ignition spark rod 14.

Then, first, a mixture of propane gas supplied from the propane gas cylinder C via the forced combustion fuel pipe A ₂ and combustion air supplied from the blower 7 via the forced combustion air pipe A ₃ is forced. Combustion burner A ₁ burns to form a flame.

At the same time, the combustion air generated by the blower 7 also flows into the purge gas combustion air pipe _B3 , and by passing through the ventilary mixer 2, the residual gas and gas in the conduit D are discharged from the purge gas pipe due to the eject effect.
The gas is sucked in through B ₂ and mixed in mixer 2, and then ejected from burner B ₁ for combustion of purge gas.

In the case of air purge, the ejected gas is ignited by the flame of the forced combustion burner _A1 serving as an ignition source, and combusted in the purge gas combustion burner _B1 .

As the remaining gas is replaced with air, it is gradually diluted and the gas no longer burns. In this case, harmful combustibles will be ejected from the purge gas combustion burner B ₁ , but since these combustibles will be ejected against the flame of the forced combustion burner A ₁ , the flame will forcibly It is burned and completely combusted and released in a harmless state.

Burner for purging gas combustion to purge residual gas like this
When burning in B ₁ , the residual gas is diluted with air, so gas in the combustible range is created in conduit D, and there is a possibility that the flame will backfire, but as mentioned above, purge piping system B is double flashback preventer 12,
13, and a flashback detector 16 that detects flashback flame and closes the solenoid valve 4 of the purge gas pipe _B2 ;
17 is also provided in duplicate, so backfire is completely prevented.

By completely preventing backfire in this way,
It becomes possible to safely perform gas purge without using inert gas such as nitrogen.

Completion of the purge can be confirmed by checking the pointer of the gas concentration meter connected in the conduit, and the output from the gas concentration meter is input to the control panel G and displayed.

After the purge is completed, turn off the operation switch and stop the operation. Incidentally, the operation may be automatically stopped after the purge is completed.

The above explanation of the operation is for the case of air purge, but the operation is similar in the case of gas purge. In addition, in the case of gas purge, contrary to the case of air purge, the purge gas combustion burner _B1 does not ignite at first, but gradually burns.

In the above description, the operation of the purge machine was automatically controlled by the control panel G, but it is of course possible to operate the purge machine manually.

(Effects) Since the present invention has the above configuration, it has the following advantages.

(1) In a combustor that is burning using another fuel,
Since the residual gas and gas in the conduit are guided and forcibly burned, it is possible to prevent unburned harmful gas from blowing out.

(2) Since the eject effect produced by flowing combustion air through the piping system is used to suction the residual gas and gas in the pipe, a source of pressure for the residual gas and air is not required.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main parts of a gas conduit construction gas/air purge machine showing an embodiment of the present invention, with some parts cut away. FIG. 2 is a sectional view of the combustor portion, and FIG. 3 is an explanatory diagram illustrating a conventional gas air purging method for gas pipe construction. A: Piping system for forced combustion, A ₁ : Burner for forced combustion, A ₂ : Fuel piping for forced combustion, A ₃ : Air piping for forced combustion, B: Piping system for purge, B ₁ : Burner for burning purge gas, B ₂ : Purge gas piping,
_B3 : Air piping for combustion of purge gas, C: Fuel gas cylinder, D: Conduit, 1, 2: Ventilation mixer.

Claims (1)

[Claims] 1. The forced combustion piping system consists of a forced combustion piping system and a purge piping system, and the forced combustion piping system includes a forced combustion burner, a forced combustion fuel piping that connects a fuel gas cylinder to the burner, and a ventilator connected to this fuel piping. The purge piping system includes a forced combustion air piping connected through a mixer, and a purge gas combustion burner, a purge gas piping that connects the burner and the conduit, and a ventilary mixer in the middle of the purge gas piping. and an air pipe for combustion of purge gas connected to the burner, and the burner for combustion of purge gas is disposed close to the burner for forced combustion so that the combustion gas is discharged into the combustion atmosphere of the burner for forced combustion. A gas and air purge machine for gas pipeline construction featuring the following.