JPH0531351Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The invention relates to a pipe flange. Specifically, when connecting pipes coated with anti-corrosion coating such as internally lined steel pipes, the end face of the pipe, This invention relates to a pipe flange that can prevent corrosion from the remaining threaded portion of the flange and the gasket seat of the pipe flange.

(Prior Art) For example, when connecting internally lined steel pipes with each other with a flange, the following two methods are available as means for preventing corrosion from the end of the pipe, the remaining threaded part of the pipe flange, and the gasket seat of the pipe flange. Mainly adopted.

First, as shown in FIG. 2, the first method is to prevent corrosion by applying an anticorrosive agent 1 to the above-mentioned corroded locations, that is, locations that come in contact with water. In addition, in Figure 2, 2
3 is a pipe flange, 3 is an inner lining steel pipe, 4 is a gasket, and 5 is a bolt or nut used to connect the pipe flanges 2 together.

The second method uses a short vinyl tube.

(Problems to be Solved by the Invention) However, the first method described above has a problem in that it is not easy to apply the anticorrosive agent 1 to corroded areas, and the process is uneven, resulting in a lack of reliability. Furthermore, in this first method, since the anticorrosive agent 1 comes into direct contact with tap water, there is a risk that the anticorrosive agent 1 will flow out.

In addition, as shown in Fig. 3 A to F, the second method includes bolt hole alignment (Fig. 3 A, scraping off the end face of the steel pipe 3 (Fig. C), the application of adhesive 6 (D in the same figure), the insertion of the short vinyl pipe 7 (E in the same figure), and the fixing with the mating flange 8 (F in the same figure) require a lot of man-hours during construction.
Moreover, it requires skill. Note that 9 in FIG. 3 indicates a hand grinder for scraping off the end face of the steel pipe 3. In addition, although this second method is suitable for hard vinyl chloride-lined steel pipes, it cannot be installed on-site because the adhesive 6 is not effective for polyethylene powder-lined steel pipes, so it has the disadvantage that all processes must be done in a factory. There is also.

The present invention aims to provide a pipe flange that can solve these problems.

(Means for Solving the Problems) The present invention is based on the resin of the anti-corrosion core on the non-pipe connection side of the tapered female thread for pipe connection provided on the threaded pipe flange that connects the lined steel pipe with the anti-corrosion core attached to the tip. The part where the screw reaches is made of resin, and the same resin as above is applied to a part of the inner circumferential side of the gasket seat located on the opposite side of the pipe connection, so the remaining threaded part of the pipe flange and the gasket can be easily removed. Can prevent corrosion of the seat.

(Example) The present invention will be described below based on an example shown in FIG.

FIG. 1 is a sectional view showing the usage state of the pipe flange according to the present invention. As shown in FIG. 1, the pipe flange 2 according to the present invention has an inner lining steel pipe 3
A resin screw 11 is attached to the tapered female thread 10 on the opposite side of the steel pipe 3 to which the tapered female thread 10 is connected.
The first feature is that it is provided to be connected to.

In addition, a second feature of the pipe flange 2 of the present invention is that a portion of the inner peripheral side of the gasket seat 12, which is the end surface on the resin screw 11 side, is coated with resin. Here, the inner circumferential part refers to the range from the inner diameter of the pipe flange 2 to the diameter approximately 5 mm larger than the inner diameter of the gasket 4 used when connecting these pipe flanges 2, 2. In the example, one side of the resin screw 11 is shown to also serve as this.

Therefore, when connecting the internally lined steel pipes 3 using the pipe flanges 2 and 2 according to the present invention constructed as described above, first, the anticorrosive cores are applied to the pipe ends of these steel pipes 3 via the anticorrosive agent 1. 13, and in this state are screwed onto the respective pipe flanges 2. At this time, the steel pipe 3 is tightened to the pipe flange 2 until the threaded portion 14 of the anticorrosive core 13 is screwed into the resin screw 11.

After that, the pipe flanges 2, 2 with these steel pipes 3, 3 tightened are bolted together through the gasket 4.
They are integrally connected using a nut 5.

Therefore, when the pipe flange 2 of the present invention is used, the end of the steel pipe 3 and the remaining threaded portion of the pipe flange 2 are prevented from coming into contact with water passing through the inside of the steel pipe 3 due to the action of the anti-corrosion core 13 and the resin screw 11. It disappears. In addition, in the pipe flange 2 of the present invention, a part of the inner circumferential side of the gasket seat 12 is coated with resin, so even if the gasket 4 is deviated during assembly or the bolts or nuts 5 are deviated, the pipe will remain intact through the gasket 4. Flange 2, 2
They are firmly crimped together to keep them out of contact with water.

The gasket 4 may be a commonly used asbestos joint sheet, rubber gasket, or the like.

(Effects of the Invention) As explained above, the pipe flange of the invention is configured in such a way that the portion of the tapered female pipe thread for pipe connection provided in a threaded pipe flange for connecting a lining steel pipe with a corrosion-resistant core attached to its tip, which is reached by the plastic thread of the corrosion-resistant core, is formed from plastic, and the same plastic is applied to part of the inner circumference of the gasket seat located on the opposite pipe connection side. Therefore, when combined with the corrosion-resistant core, it provides excellent corrosion resistance and is also easy to install.

Furthermore, by using the pipe flange of the present invention, it can be used for vinyl chloride-lined steel pipes and polyethylene powder-lined steel pipes that cannot be bonded, by using different anti-corrosion cores.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a pipe flange according to an embodiment of the present invention in use, Fig. 2 is a drawing similar to Fig. 1 when a conventional pipe flange is used, and Fig. 3
Figures A to F are explanatory diagrams showing the drawbacks when using other conventional pipe flanges. 2 is a pipe flange, 3 is an inner lining steel pipe, 1
0 is a tapered female thread, 11 is a resin thread, and 12 is a gasket seat.

Claims (1)

[Scope of utility model registration request] A portion of the taper female thread for pipe connection provided on the threaded pipe flange that connects the lining steel pipe with the anticorrosive core attached to the tip thereof, on the opposite pipe connection side, where the resin thread of the anticorrosive core reaches, is made of resin, and A pipe flange characterized in that a part of the inner peripheral side of a gasket seat located on the pipe connection side is coated with the same resin as described above.