CN101254373A - a mesh filter - Google Patents

Abstract

The invention relates to a net filter and belongs to the technical field of water-saving irrigation. The technical solution includes a casing, a water inlet, a water outlet, and a sewage valve, and is characterized in that a multi-stage cylindrical wall filter is coaxially installed in the casing, and the mesh of the filter near the water inlet is large, The sieve hole of the filter screen near the water outlet side is small. The filter screen of the present invention adopts a multi-layer cylindrical wall surface type, and is structurally divided into multi-layer filter screens from coarse to fine, such as adopting three-layer filter screens. A coarse filter is used at the water inlet, a fine filter is used at the water outlet, and a medium filter is placed between the two. This structure allows impurities of different particle sizes to be intercepted by different filters, which reduces the load on each filter and prolongs the working time of filtration.

Description

a mesh filter

technical field

The invention relates to a net filter and belongs to the technical field of water-saving irrigation. It consists of a shell, an upper cover, an inlet, an outlet, and a sewage valve. It is characterized in that a multi-stage cylindrical wall filter is coaxially installed in the shell, and the filter on the side close to the water inlet has a large mesh. The sieve hole of the filter screen near the water outlet side is small.

technical background

The filter is an important key component in the micro-irrigation system. It filters the impurities and dirt in the irrigation water to make the water quality meet the requirements of the micro-irrigation system. It is required to have a simple structure and low price, so the commonly used filters mainly include mesh filters, laminated filters, sand filters and water-sand separators. Among them, the mesh filter is the most commonly used one.

Mesh filter Filtration principle: There is a sieve-like filter element inside the filter. When dirty water passes through the filter element, the impurities in the water are trapped on the sieve, and the clean water flows into the downstream irrigation pipeline. When the dirt on the screen reaches a certain amount, they are flushed out of the system through a cleaning process.

Generally, the filter surface of the mesh filter is a single cylindrical wall surface. When the water quality is not good, especially when the sediment content is high, the filter is particularly easy to filter because the sediment of different sizes is blocked on the same layer of filter net. Blockage requires frequent and repeated flushing, which affects the operating efficiency and function of the irrigation system, and also reduces the service life of the filter.

Contents of the invention

The purpose of the present invention is to provide a screen filter capable of intercepting silt with different particle sizes on different screens, which has the characteristics of high pollution interception capacity and long washing cycle.

The technical solution adopted in order to achieve the purpose of the present invention includes a casing, a water inlet, a water outlet, and a sewage valve, and it is characterized in that a multi-layer cylindrical wall filter screen is coaxially installed in the casing, and the side close to the water inlet The filter screen is a coarse filter screen with large sieve holes, and the filter screen near the water outlet is a fine filter screen with small sieve holes.

In the above-mentioned mesh filter, the filter screen has three stages, which are coarse filter screen, medium filter screen and fine filter screen.

In the above mesh filter, the water inlet is arranged on the axis of one end of the filter mesh, and the drain valve is arranged at the other end of the filter mesh.

In the above mesh filter, the water inlet is arranged on the side of the filter shell, and at this time, the coarse filter is arranged on the outermost layer.

In the above-mentioned mesh filter, drain valves are installed between the multi-layer filter screens to realize independent flushing of each layer of filter screens.

In the above-mentioned screen filter, a cleaning brush assembly for cleaning the filter screen may be provided in the housing.

The filter screen of the present invention adopts a multi-layer cylindrical wall surface type, and is divided into thick to fine multi-layer filter screens in structure. If a three-layer filter screen is used, a coarse filter screen is used for the water inlet, and a fine filter is used for the water outlet. net, the middle filter is between the two. This structure allows impurities of different particle sizes to be intercepted by different filters, which reduces the load on each filter and prolongs the working time of filtration.

The mesh filter has good flushing effect, strong dirt interception ability, long flushing period, simple structure and low price.

Description of drawings

Fig. 1 is the normal filtering state figure of mesh filter of the present invention;

Fig. 2 is the cleaning state figure of screen filter of the present invention;

Fig. 3 is a partially enlarged view of the sealing gasket between the filter screen of the present invention, the filter upper cover, and the housing.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

The filter includes shell, upper cover, water inlet, water outlet, sewage valve, primary screen (coarse filter), secondary screen (medium filter), and third screen (fine filter) (see figure 1, Figure 2).

In Figure 1, 1 is the water inlet of the filter, 2 is the shell of the filter, 3 is the first layer of filter (coarse mesh), 4 is the third layer of filter (fine mesh), 5 is the second layer of filter (middle net), 6 is the sealing gasket between the filter shell and the upper cover, 7 is the sewage outlet of the second layer of filter screen, 8 is the sewage outlet of the first layer of filter screen, 9 is the upper cover of the filter, 10 is The sewage outlet of the third layer filter screen, 11 is a fixed bolt assembly, 12 is a water outlet, and 13 is a sealing washer. In this embodiment, there are three layers of filter screens, the first layer of filter screen 3 is close to the water inlet, so the mesh of the filter screen is large, the third layer of filter screen 4 is close to the water outlet, the mesh of the filter screen is small, and the second layer of filter screen The filter screen 5 is located between the first layer of filter screen 3 and the third layer of filter screen 4, and the mesh size of the filter screen is also between the two. In actual production, if the filtration accuracy is required to be higher, the structure of four-layer filter screen can also be considered.

In the above embodiment, the water inlet is set on the axis of one end of the filter screen, the drain valve is set at the other end of the filter screen, and the water outlet is set on the side of the casing. In actual production, the water inlet can also be arranged on the side of the filter housing, and at this time, the coarse filter screen is arranged on the outermost layer.

Each filter screen is provided with a blowdown valve, which is installed at the blowdown outlets 7, 8, and 10 respectively. In this way, each layer of filter screen can be washed independently, that is, according to the actual clogging situation of the filter, both three layers of filter screens can be washed at the same time, and only one or two layers of filter screens can be washed.

The filter works as follows:

Water flows into the first filter cavity from the water inlet of the filter, and first passes through the first-level screen (coarse filter), and the relatively coarse impurities are intercepted on this filter; water and finer impurities enter through the first-level screen. The second filter cavity passes through the secondary screen (middle filter), and the secondary coarse impurities are intercepted on this filter; water and fine impurities pass through the secondary screen and enter the third filter cavity, and pass through the third screen The fine impurities are intercepted on this filter; the water passing through the third-stage screen (fine filter) is clean water that meets the irrigation water quality requirements, and flows from the filter outlet into the downstream irrigation pipeline.

As shown in Figure 2, the flushing method of this filter is the direct flushing type. When there is a lot of dirt on each layer of the filter, the sewage valve (solenoid valve) is opened through the pressure difference or timing controller, and the sewage is washed through the sewage outlet. go out.

As shown in FIG. 3 , the filter screen is embedded with the filter housing or the upper cover through a sealing gasket 13 .

In actual production, a cleaning brush assembly for cleaning the filter screen can also be arranged in the housing.

Experiments show that adopting the strainer type filter of the present invention (120 order fine filter screen+80 order medium filter screen+30 order coarse filter screen) compares with common 120 order filter, at the concentration that silt content is 50mg/L (The range of sediment particle size is: less than 0.075mm accounts for 36%, 0.075-0.1mm accounts for 10%, 0.1-0.15mm accounts for 24%, and more than 0.15mm accounts for 30%). After 8 hours, the pressure difference between the front and back of the filter reaches 50kPa, that is, the filter has been clogged to the extent that it needs to be cleaned; while the filter of the present invention runs for 10 to 12 hours before it reaches the extent that it needs to be washed. Therefore, the present invention prolongs the filtering working time.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention without limitation, although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solution of the present invention can be Modifications or equivalent replacements without departing from the spirit and scope of the technical solutions of the present invention shall be covered by the claims of the present invention.

Claims (6)

1, a kind of well strainer comprises shell, water inlet, delivery port, blowoff valve, it is characterized in that, in described shell, be coaxially installed with multilayer cylinder wall surface type filter screen, and the filter screen near the water inlet one side is a coarse strainer, its sieve aperture is big, filter screen near the delivery port one side is a fie screen, and its sieve aperture is little.

2, well strainer according to claim 1 is characterized in that, described filter screen has three layers, is respectively coarse strainer, middle filter screen and fie screen.

3, well strainer according to claim 1 and 2 is characterized in that, described water inlet is located on the axis of filter screen one end, and blowoff valve is located at the other end of filter screen.

4, well strainer according to claim 1 and 2 is characterized in that, described water inlet is located at the side of filter housing, and at this moment, coarse strainer is located at outermost layer.

5, well strainer according to claim 1 and 2 is characterized in that, blowoff valve all is housed between the described multistorey strainer mesh.

6, well strainer according to claim 1 and 2 is characterized in that, can be provided with the cleaning brush assembly that cleans filter screen in described shell.

Images