JPH01155919A - Strainer with cleaning function of screen - Google Patents

Abstract

PURPOSE:To perfectly clean without disassembling by forming a screen with an electric magnet and forcedly removing the foreign matter stuck to the screen by the electric magnet disposed on a primary side surface with a specified distance. CONSTITUTION:The screen 5 is always magnetized during normal operation so that the foreign matter such as carbon or dust, etc., is stuck to the fine pores of the screen 5 and accumulated. When the accumulated amount is increased and the liquid passing area of the screen 5 is decreased so that the pressure difference between a flow outlet 3 side and a flow inlet 2 side becomes larger than the standard value, the magnetizing of the screen 5 is stopped by a controller 11 and the electric magnet 4 of screen shape or rod shape, etc., is magnetized so that the foreign matter stuck to the surface and pores of the screen 5 is stuck to the surface of the electric magnet 4. After a specified time, the magnetizing of the electric magnet 4 is stopped, and, by opening a discharge valve 8, the foreign matter is discharged to the outside of the unit by the liquid pressure on primary side.

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a strainer that is installed in the middle of a fluid pipe to remove foreign matter from the fluid, and in particular has a function of discharging foreign matter caught by a screen to the outside of the device. related to things.

Prior Art Fluids, especially steam and its condensate, contain many foreign substances such as carbon and dust, and these foreign substances can cause problems in various valves,
For example, it adhered to the valve opening of a steam trap, causing various problems.

Therefore, conventionally, Y
There is something called a mold strainer. This has an inlet and an outlet for fluid in the main body, and a porous cylindrical screen is placed between the inlet and the outlet, and is designed to discharge foreign matter stuck in the pores of the screen to the outside of the vessel. It consists of a discharge valve.

Problems to be Solved by the Invention In the strainer, when the fluid that flows in from the inlet passes through the screen, foreign substances such as dust and carbon contained in the fluid are accumulated in the pores and removed.

As the amount of accumulated fluid increases, the fluid passage area of the screen decreases and eventually the fluid stops flowing. Therefore, a discharge valve installed at the bottom of the screen removes the accumulated foreign matter.

However, at this time, large foreign objects on the screen surface are discharged out of the vessel by the primary fluid pressure, but small foreign objects stuck in the pores cannot be removed and remain. The only way to completely remove the problem was to remove the screen from the main unit and clean it.

As a result of analyzing the components of foreign substances such as carbon and dust,
The main component was found to be iron.

In particular, in piping through which high-temperature, high-pressure fluid such as steam flows, oxidation of the metal surface is accelerated and corrosion is significant.

Taking this point into consideration, the technical means of the present invention taken to solve the above problems has an inlet and an outlet, and a screen for trapping foreign matter is provided between the inlet X and the outlet. In the strainer, the screen is formed of an electromagnet, and the electromagnet is arranged at a short distance so as to face the entire primary side of the screen, and a discharge valve is provided for discharging foreign matter caught by the screen. and when the screen of the electromagnet is magnetized, the electromagnet is not magnetized and the discharge valve remains closed, and when the screen is demagnetized, the electromagnet is magnetized and set to marry. The strainer is configured such that the discharge valve is placed in an open state at the same time as the magnetization of the electromagnet is cut off after a period of time.

Operation During normal operation, the screen is always magnetized, and foreign matter (iron) in the fluid adheres to the pores of the screen and accumulates.

As the amount of accumulation further increases, the area through which the fluid passes through the screen becomes smaller, and when the fluid becomes difficult to flow, the magnetization of the screen is cut off and the electromagnet is magnetized. Then, foreign matter adhering to the surface and pores of the screen is attracted to the electromagnet and adheres to the surface. Thereafter, when the magnetization of this electromagnet is also cut off and the discharge valve is opened, the foreign matter becomes free and is blown out of the vessel from the discharge valve by the action of the primary pressure flow and is discharged.

Effect Foreign matter attached to the screen is forcibly removed using an electromagnet, so it can be completely cleaned without disassembling the screen from the main body. In addition, since the screen is magnetized, it is possible to remove small foreign objects that would otherwise pass through. Therefore, the valve provided on the secondary side of the strainer operates well without clogging the valve port.

Embodiment An embodiment illustrating a specific example of the above technical means will be described. (See Figure 1) A fluid inlet 2 and an outlet 3 are provided in the main body 1, and porous cylindrical screens 4 and 5 are arranged between the inlet 2 and the outlet 3, and fixed with a screen holder 6. do. The screens 4 and 5 are formed into electromagnets by winding a coil (not shown) around a portion thereof. The roughness of the screen is rougher in 5 than in 4.

An exhaust lower to the outside of the device is formed in the screen holder 6, and an electric valve 8 is connected thereto. Also, screens 4 and 5 are installed on the side of the screen holder 6, and pressure sensors 9 and 1 are installed on the inlet 2 side and the outlet 3 side relative to the magnetized screens 4 and 5.
0 is installed, and the respective signals from there are input to the controller 11 to constantly check the differential pressure.

Controller 11, power supply line 12 to the coil, electric valve 8
and connect them respectively. The controller 11 houses control equipment that performs the following operations.

At the beginning of operation and during normal operation, when the screen is not clogged, the pressure difference between the inlet 2 side and the outlet 3 side is minute, so the controller 11 determines that it is normal, the screen 4 is not magnetized, and the screen 5 is is placed in a magnetized state. Further, at this time, the electric valve 8 is in a closed state.

Large foreign particles (iron) flowing in from the inlet 2 are removed by a screen 4, and small particles that cannot be removed there are attracted by the pores of the screen 5 and magnetic force. At this time, even small foreign objects that pass through the pores of the screen are normally attracted and removed because the screen 5 itself is magnetized.

When foreign matter accumulates in the screen contact area and in the screen 5, and the amount of accumulated foreign matter increases, the fluid passage area of the screen increases and the controller 11
The voltage supplied to the screen 5 is cut off, and the magnetization is also cut off. At the same time, power is supplied to the screen 4 to magnetize it. Then, the foreign matter adhering to the pores of the screen 5 is forcibly drawn to the screen 4 and adheres to its surface.

After allowing the screen 4 to perform an adsorption action for a certain set time, the magnetization of the screen 4 is also cut off and the electric valve 8 is opened. ) is also discharged outside the vessel by the action of the fluid pressure on the downstream side.

After discharging for a certain period of time, the electric valve 8 is closed to restore the magnetized state of the screens 4 and 5 to their original state.

Here, as a guideline, the pressure difference between the incoming side and the secondary side should be approximately 0.3 when the screen is not clogged. A value below 'j/crA is considered normal, and anything above that is considered to be clogged. It is.

Although the screen 4 is not initially magnetized in this embodiment, it may be magnetized. Further, the screen 4 may be an ordinary rod-shaped electromagnet without a screen function.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of this embodiment. 1: Main body 2: Inlet 3: Outlet 4,5 Niclean 8: Electric valve 9, 10: Pressure sensor - 11: Controller

Claims (1)

[Claims] 1. In a strainer having an inlet and an outlet, and a screen for trapping foreign matter provided between the inlet and the outlet, the screen is formed of an electromagnet, and the entire primary side of the screen is Electromagnets are arranged facing each other at a distance, and a discharge valve is provided to discharge foreign matter captured by the screen, and when the screen of the electromagnet is magnetized, the electromagnet is not magnetized. The discharge valve remains closed, and when the screen is demagnetized, the electromagnet is magnetized, and after a certain set time, when the electromagnet is also demagnetized, the discharge valve is opened. A strainer with a screen cleaning function configured as follows.