JPH03272388A - Blow method in active pipe branching method - Google Patents

Abstract

PURPOSE:To return blow fluid by directly pressurizing the blow fluid by causing the blow fluid to flow through a main pipe through a blow piping, recovering chips by means of a filter, further causing the blow fluid to flow through an orifice to reduce a pressure, and returning the blow fluid in the main pipe in a state that the fluid is boosted in a circulating pipe with the aid of a pressure pump. CONSTITUTION:A blow piping 120 is incorporated, and fluid in a main pipe 100 is introduced through a feed branch pipe 121 to fill all of the blow piping 120, a branch short pipe 102, a gate valve 103, and a boring tool 104 with the fluid. The blow piping 100 is bored by the boring tool 104. When a drill 107 is started to drill through the main pipe 100, a valve 108 and a feed valve 122 are opened. Fluid flows through a filter 123, chips are recovered and filtered. The filtered fluid is caused to flow through an orifice 124 for reduction of a pressure, and the fluid is boosted with the aid of a pressure pump 125 to press it in the main pipe 100. As a result, a storage container is eliminated, a space is saved, and chips are recovered and blow fluid is re-used with high efficiency.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a blowing method used for collecting chips in a live pipe branching method, and in particular to a method in which the fluid to be blown (blow fluid) is directly pressurized. This relates to a blow method that returns the pipe to the main pipe.

[Conventional technology] Two live pipe branching methods for branching live pipes of main pipes that supply water, gas, etc. are one method that performs live pipe branching work by reducing the pressure inside the main pipe, and one method that performs live pipe branching work without reducing the pressure inside the main pipe. There is a construction method (hot tap method).

The method of performing live pipe branching work by reducing the pressure inside the main pipe is superior in safety because it reduces the pressure, but it takes time and effort to reduce the pressure, making it difficult to speed up the work and preventing the main pipe from being exposed to gas. When installing pipes, gas replacement work is also required, which takes even more time and effort, and even in live pipe branching work, there is a problem in that customers are inconvenienced during depressurization work.

Therefore, in recent years, in consideration of the inconvenience to customers, many methods have been adopted to perform live pipe branching work without reducing the pressure inside the main pipe.

Part 2 about this live pipe branching method using the hot tap method.
This will be explained using figures.

For example, when taking out the branch pipe 101 from the main pipe 100 of the gas pipe, without reducing the pressure inside the main pipe 100,
In addition, in order to perform live pipe branching without stopping the gas flow in the main pipe 100, first weld a short branch pipe 102 to the main pipe 100,
A gate valve 103 is attached to this.

Next, as shown in FIG. 2(a), the gate valve 103
The punching machine 104 is set at . This drilling machine 104 has a shaft 1
05, and a cylindrical cutter 106 having a drill 107 is attached to the tip of the shaft 105. The shaft 105 is rotated by an external drive source (not shown) such as an air motor, and the cutter 106 and Drill 1
07. Therefore, when the cutter 106 and the drill 107 are rotated and fed toward the main pipe 100, the drill 107 drills the main pipe 100 as shown in FIG. perforate.

During this drilling operation, the fluid gas in the main pipe 100 is transferred to the branch short pipe 102. It flows into the gate valve 103 and the perforator 104. However, since the perforator 104 is sealed, the gas flowing into the perforator 104 will not leak to the outside.

When the drilling of the main pipe 100 is completed, the rotation of the cutter 106 and the drill 107 is stopped, and the cutter 106 and the drill 107 are drawn into the drilling Ma 104 and stored. Thereafter, the disk 103a of the gate valve 103 is closed and the perforator 104 is removed from the gate valve 103 (FIG. 2(C)).

Thereafter, when the branch pipe 101 is connected and the gate valve 103 is opened, gas flows through the branch pipe 101, and the active pipe branching operation is completed as shown in FIG. 2(d).

By the way, as mentioned above, when drilling the main pipe 100 with the drill 107 and the cutter 106, chips are generated, but instead of flowing into the main pipe 100, the chips are collected in the branch short pipe 102 to be collected outside. Open the provided blow valve 108 and open the main pipe 1.
Chips are collected on the fluid flowing from 00 to the branch short pipe 102.

To explain this chip collection method with reference to Fig. 3, the flowmeter 1
09 and a flow rate control valve 110 is connected to the branch short pipe 102 via the blow valve 108, and the other end of the blow pipe 111 is connected to a plurality of containers (for example, drums) 112 and 1128 with valves, respectively. 113,11
3a, and the blow fluid that flows into the branch short pipe 102 from the main pipe 100 through this blow pipe 111 is put into one container 112, and when it is filled, it is put into the next empty container 112a. This procedure collects the blow fluid containing chips. Then, the container filled with the blow fluid is transported to another location, the chips and the fluid are separated in a subsequent process, and the separated fluid is reused.

[Problems to be Solved by the Invention] However, the recovery of chips by the conventional blow method as described above has the following problems.

■In order to put the blowing fluid into the container, space occupied by the container is required, and it is difficult to employ such a blowing method when working in a plant with limited space.

■When the fluid is a hazardous substance, it is necessary to handle and transport a large amount of the hazardous substance, so the work is always accompanied by danger.

The present invention solves the above-mentioned problems with the fluid treatment in the conventional blow method using the live pipe branching method, and provides a blow method in which the blow fluid can be directly pressurized and returned to the main pipe. It is an object.

[Means for Solving the Problems] In order to achieve the above object, the blow method in the live pipe branching method according to the present invention removes chips generated when carrying out the live pipe branching method by branching the main pipe to a shorter length. In the blow method, which collects the blow fluid together with the blow fluid flowing into the pipe, the blow fluid is passed to the main pipe through the blow pipe connected to the branch short pipe via the blow valve, and as the blow fluid flows through the blow pipe, a filter is used to collect the blow fluid. The chips are collected and the blow fluid is filtered, and the pressure of the filtered fluid is reduced by passing it through an orifice, and the pressure of the reduced pressure of the filtrate is increased by a pressurizing pump in the circulation pipe installed in the blow piping. It was designed so that it could be returned to the main pipe.

[Function] In the live pipe branching method, when the drill of the drilling machine begins to penetrate the main pipe, the fluid flowing through the main pipe begins to blow, and this blown fluid flows into the short branch pipe connected to the main pipe.

The branch short pipe, the blow pipe connected to it, the gate valve, and the inside of the drilling machine are filled with the same fluid as the main pipe, so when the pressure pump is activated, a pressure difference is created at the orifice, and this The pressure difference causes the fluid to begin to move, and the blow fluid begins to flow through the blow piping. During the flow of the blow fluid, the filter captures and collects chips mixed in the blow fluid. Since the filtered blow fluid is depressurized by passing through the orifice, the pressure is increased in the circulation pipe by the pressurizing pump and the fluid is pressurized into the main pipe.

[Example] Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram of blow piping for carrying out the blow method of the present invention. The blow pipe 120 is connected between the short branch pipe 102 and the feed branch pipe 121 connected to the downstream side of the main pipe 100 via a blow valve 108 and a feed valve 122, respectively. Flow meter 109 in order from the upstream side. Filter 123. Flow control valve 110. An orifice 124, a pressure pump 125, and a check valve 126 are provided. Further, a circulation pipe 127 is connected between the upstream side and the downstream side of the pressurizing pump 125, and a check valve 128 and a valve 129 are provided in the fluid flow direction. Further, a bypass pipe 131 having a valve 130 is provided on both sides of the check valve 126.
are connected. Although one filter 123 is shown, it is practical to connect two or more filters in parallel and use and replace them alternately or sequentially by switching valves. .

By configuring the blow plumber 20 as described above,
The chips mixed in the blow fluid are captured by the filter 123, and at the same time, the pressure of the filtered fluid is reduced by the orifice 124, and the fluid is blown due to the pressure difference between the pressure inside the main pipe 100 and the pressure at the outlet of the orifice 124. Piping 12
Flows through 0.

The reduced pressure of the filtered fluid is then increased in pressure within the circulation pipe 127 by the pressurizing pump 125 to obtain a higher pressure than the pressure on the downstream side of the main pipe 100, and returned to the main pipe 100 through the feed branch pipe 121. I can do it.

The procedure of the blow method using this blow pipe 120 is as follows.

(Step l) First, as shown in Fig. 1, install the blow piping 120,
Before starting to drill mains 100, inlet valve 122. The valve 130 of the bypass pipe 131 and the blow valve 108 are opened, the fluid in the main pipe 100 is introduced from the feed branch pipe 121, and the fluid is introduced into the blow pipe 120 and the branch short pipe 102. Gate valve 103.
All of the drilling machines 104 are filled with the fluid in the main pipe 100. Whether or not the fluid is filled is determined by opening the release valve 114 provided in the drilling machine 104. After the fluid is filled, valve 130 and blow valve 108 are closed.

However, only the inlet valve 122 is left open.

(Step 2) When the main pipe 100 is drilled with the drilling machine 104 and the drill 107 reaches the inside of the main pipe 100 (this can be determined by the reading of the length measuring device attached to the drilling machine), the inside of the main pipe 100 is fluid begins to move to the branch short pipe 102.

Therefore, about one minute before the drill 107 penetrates, the inlet valve 122 is closed, the pressurizing pump 125 is operated, and the fluid is circulated within the circulation pipe 127. This is because the fluid is circulated in a closed loop, and if this is done for a long time, a load will be applied to the pump 125 and the pump 125 will malfunction, so it is necessary to do this a little before the drill 107 penetrates the main pipe.

(Step 3) Then, when the drill 107 begins to penetrate the main pipe 100, the blow valve 108 and the inlet valve 122 are opened. Then, the fluid in the blow pipe 120 begins to flow toward the feed branch pipe 121 by the pressurizing pump 125. As the fluid passes through the filter 123 and the orifice 124, a pressure loss occurs, and the pressure is increased by the pressurizing pump 125, and the inlet branch pipe 1
21 into the main pipe 100.

(Step 4) As the drilling into the main pipe 100 progresses, the area of the drilling into the main pipe 100 by the cutter 106 increases, and the flow rate to be blown increases accordingly. In that case, the circulation pipe 127
Close valve 129.

The blow method according to the present invention has been described above, but it goes without saying that the pressure pump 125 used should be selected so that the pressure raised by the capacity is greater than the pressure value in the main pipe. Note that after the connection of the branch pipe 101 is completed, the blow valve 108 and the feed valve 122 are closed, and the blow pipe 120 is removed.

[Effects of the Invention] As described above, according to the present invention, the blow fluid can be directly pressurized and returned to the main pipe, which eliminates the need for a conventional blow fluid storage container, thus saving space and space. Naturally, there is no need for transportation, so there is an effect that it becomes possible to collect chips and reuse the blow fluid more safely and efficiently than in the past.

[Brief explanation of drawings]

Figure 1 is a diagram of the blow piping used in the blow method of the present invention.
FIGS. 2(a) to 2(d) are explanatory diagrams showing the procedure of the conventional live pipe branching method, and FIG. 3 is an explanatory diagram showing the swarf collection method in the live pipe branching method of FIG.

Claims (1)

[Claims] In a blow method in which chips generated when performing a live pipe branch method are collected together with blow fluid flowing from a main pipe into a branch short pipe connected to the main pipe, the blow fluid is transferred to the branch short pipe by a blow valve. The blow fluid is connected to the main pipe through a blow pipe connected through the pipe, and in the process of the blow fluid flowing through the blow pipe, the chips are collected by a filter and the blow fluid is filtered, and the filtered fluid is The blow in the live pipe branching method is characterized in that the pressure is reduced by passing through an orifice, and the reduced pressure of the filtered fluid is increased in pressure by a pressurizing pump in a circulation pipe provided in the blow piping and returned to the main pipe. Construction method.