JPH0581675B2 - - Google Patents

Description

[Detailed description of the invention] (a) Field of industrial application The present invention relates to a method for stopping red water in plastic lined pipe equipment installed in a building, and in particular,
The present invention relates to a method for shutting off red water in existing water pipes in buildings, such as buildings and ships. The present invention also relates to a method for rehabilitating pipe joints of plastic-lined piping equipment that have been installed and have formed rust, and particularly relates to a method for rehabilitating pipe joints of existing water pipes in a building by stopping corrosion.

(B) Prior Art In general, plastic lined pipes have been used for water pipes in buildings, and pipe joints are used to connect these plastic lined pipes. Recently, corrosion-resistant pipe fittings have been used, but in the past, general pipe fittings were used, and corrosion of pipe fittings and pipe fittings such as pipe ends cannot be avoided over time. Due to corrosion or deterioration of pipe joints over time, rust occurs in the joints, which causes so-called red water.

Red water can be caused by colored laundry, washbasins,
It stains sanitary utensils such as toilet bowls, makes food and tea taste bad, and causes psychological and physiological discomfort to people, and as an industrial raw material, it causes coloring of products and deteriorates their quality. That's a problem.

In order to avoid such red water, plastic lined piping equipment is updated or pipe joints are replaced when red water occurs.

(c) Problems to be solved by the invention However, as a countermeasure against such red water, updating the entire plastic lined piping equipment requires a lot of time and effort because it is carried out on the existing plastic lined piping lines that are laid in a complicated manner. It takes
Moreover, the plastic lined tube that is still usable must be discarded, which is uneconomical. In addition, even if only the pipe joint is replaced, the front and rear of the pipe joint must be cut, and new pipe joints must be attached to both ends of a pipe of an appropriate length to connect the new pipe joint. This is problematic because it requires twice the number of items and requires a lot of effort.

The present invention aims to solve problems related to red water countermeasures in existing piping equipment.

(d) Means for solving the problems The present invention provides red water countermeasures for existing plastic lined piping equipment without replacing pipe joints or updating the plastic lined piping equipment.
The purpose of the present invention is to provide a method for stopping red water that can be performed easily and at low cost.

That is, the present invention prevents rust from forming on the inner surface of the pipe joints of a pipe line in which a plurality of plastic lined pipes are connected by a plurality of pipe joints and installed inside a building, causing red water to enter the pipe line. In the method of stopping red water in a pipe line that has caused red water to occur, drain water from the pipe line that has been laid in a building and that has caused red water to occur, drill a hole in the wall of each pipe joint in the pipe line, and remove the water inside each hole. In each case, a corrosion-resistant anode electrode is attached with an insulating seal around it and protruded into the pipe joint, water is poured into the pipe line, the anode electrode is connected to the anode of an external power source, and each By connecting the pipe joint to the cathode of an external power source and energizing it, a corrosion-protective potential is generated between the anode electrode and the wall of the pipe joint, thereby preventing the formation of red water in the piping path where rust has formed. And there is a red water stop method.

In the present invention, examples of the anode electrode member used include generally corrosion-resistant anode members, such as platinum-coated titanium electrodes used in galvanic corrosion protection technology for the inner surfaces of hot water tanks and boilers. In addition, in the present invention, a corrosion-resistant anode electrode member,
A highly elastic insulating material is disposed to seal around the anode electrode member in order to electrically insulate it from the pipe fitting member. As such an insulating material, any electrically insulating material can be used as long as it is water resistant and impermeable. However, from the standpoint of sealing, etc., it is preferable to use elastic materials such as rubber, plastic adhesives, etc., which have excellent sealing properties.

In the present invention, the smaller the hole provided in the pipe joint, the fewer members are required. However, if a packing member is provided around the electrode in advance to create an electrode seal structure, and this is formed into a plug shape to fit into the hole formed in the pipe joint, red water countermeasure work will be simple and easy. preferable.

(e) Effect In the present invention, when red water is generated in the existing plastic lined piping equipment, the water supply pipe stop valve of the plastic lined piping equipment is closed to drain the water in the pipe, or the upstream side Close the water shut-off valve, and for example, select all pipe joints or pipe joints that are severely corroded, drill a hole through the inside of the pipe joint wall, and fill the hole with electrically insulating material. Since a corrosion-resistant anode electrode is disposed through the tube and a cathode electrode is connected to the wall of the pipe joint, a voltage is applied between the anode and the cathode so that the corrosion-resistant potential, for example, the potential of the cathode is at the saturation electrode potential - Corrosion protection can be achieved by setting the potential to 770mv (SCE). By stopping the corrosion of the pipe joint, the red water is stopped and clean water can be supplied.

(f) Example Hereinafter, one embodiment of the red water stopping method of the present invention will be described with reference to the accompanying drawings, but the present invention is not limited in any way by the following explanation and illustrations. do not have.

FIG. 1 is an explanatory diagram schematically showing a pipe joint part in an embodiment of the present invention, and shows an example of application to an L-shaped pipe joint.

FIG. 1 shows a connection section where plastic lined pipes 2 and 3 of an existing plastic lined piping facility 1 are connected by a pipe joint 4. In this example, the pipe joint 4 is not lined.
For this reason, as corrosion progresses over time, pipe joints 4
Rust occurs on the inner surface and forms red water. When red water is generated in this manner, in this example, the entire piping equipment 1 is drained, and a through hole 6 is formed in the outer curved portion 5 of the pipe joint 4. The through hole 6 is formed at one location on the wall 7 of the outer curved portion 5 of the pipe joint portion 4 using, for example, an electric drill. The shape of this hole 6 is tapered so as to open toward the inside of the pipe joint.
It is preferable that the plug 9 is fitted into the hole 6 because it is effective in preventing the stopper 9 from coming off. The positions of the holes 6 formed in the pipe fitting 4 are preferably such that the distances from the pipe end 10 to the anode electrode 8 are approximately the same; however, depending on the installation of the piping equipment 1, If it is not possible to form holes equidistant from the end 10,
There is no problem even if holes are made in other locations and the anode electrode 8 is attached.

The plug body 9 includes a short, solid cylindrical body 11 made of an electrically insulating material such as rubber, and two disks 12 made of a corrosion-resistant material such as stainless steel and having approximately the same diameter attached to the upper and lower ends of the cylindrical body, respectively. and 13. These cylindrical body 11 and disks 12 and 13 include
Screw holes 14 and 15 for tightening and a mounting hole 16 for the anode electrode 8 are formed, respectively. The outer disk 12 is formed larger than the inner disk 13 and larger than the through hole 6 formed in the pipe joint wall, and is further sealed with an electrically insulating adhesive or the like. You can also do this.

The plug formed in this way is attached to the pipe joint wall 7.
Insert the cylindrical body part 11 into the through hole 6 of
7 and 18 are screwed together, the cylindrical body 11 can be compressed in the axial direction, bulged in the lateral direction, that is, in the direction of the pipe joint wall 7, and fixed to the pipe joint wall 7.

The plug body 9 is fixed to the pipe joint wall 7, and the connection terminal 19 of the anode electrode 8 is connected to a constant voltage power source (not shown).
Connect to. On the other hand, the cathode (not shown)
is connected to a part of the plastic lined pipe wall of the plastic lined piping installation 1. When installing red water stop electrodes to multiple pipe joints, connect the connection terminal of the anode electrode 8 of each pipe joint to one conductor, and connect this conductor to a DC constant voltage power supply to complete the wiring circuit. It can be simplified.

In this way, the electrical corrosion protection electrode 8 is attached to the pipe joint wall 7, and tap water with a total iron content of 0.07 ppm is applied to the pipe equipment 1.
At the same time, the cathode side potential is -770mv (SCE)
In this case, the red water stopped, but the total iron content was 3.94ppm if the galvanic corrosion protection anode electrode was not installed.
The occurrence of red water was observed.

(G) Effects of the Invention The present invention provides an anode electrode that is electrically insulated from the pipe joint and protrudes from the inside of the pipe joint, and a cathode that is connected to the pipe joint where red water is generated in existing plastic lined piping equipment. Since it is connected to the wall, voltage can be applied between the anode and cathode to stop the red water.

Therefore, compared to conventional methods, the present invention provides
Red water can be stopped with simple work and at low cost without replacing pipe joints and plastic lined piping equipment.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram schematically showing a pipe joint part in an embodiment of the present invention, and shows an example of application to an L-shaped pipe joint. Regarding the symbols in the diagram, 1 is piping equipment, 2 and 3
is a plastic lined pipe, 4 is a pipe joint, 5 is an outer curved part of the pipe joint, 6 is a through hole, 7 is a wall of the pipe joint, 8 is an anode electrode, 9 is a plug body, 10 is a pipe end, 11
is a cylindrical body, 12 and 13 are disks, 14 and 15 are screw holes, 16 is a mounting hole, 17 and 18 are screws, 1
9 is a connection terminal.

Claims (1)

[Claims] 1 Piping where rust has formed on the inner surface of the pipe joints of a pipe line in which multiple plastic lined pipes are connected by multiple pipe joints and pipes are laid inside a building, resulting in red water inside the pipe line. In the method of stopping red water in pipes, water is drained from the pipes laid in the building that have caused red water, holes are drilled in the wall of each pipe joint in the pipes, and a corrosion-resistant material is installed in each hole. Attach a positive anode electrode with an insulating seal around the circumference and protrude into the pipe joint, fill the pipe with water, connect the anode electrode to the anode of an external power source, and connect each pipe joint to the external power source. A method for stopping red water, characterized in that the generation of red water in the piping path where rust has been formed is prevented by generating a corrosion-protective potential between the anode electrode and the wall of the pipe joint by connecting to the cathode of the pipe and applying electricity. .