阅读说明：本技术 一种机制砂复合筛网细度模数调节方法 (Method for adjusting fineness modulus of machine-made sand composite screen ) 是由 朱先杰 严章国 覃信海 张昌晶 沈杰 杨胜军 邓飞 钱永亮 张延� 杨志明 亓朝 于 2020-11-18 设计创作，主要内容包括：本发明提供的一种机制砂复合筛网细度模数调节方法；包括n个筛网区,n个筛网区依次排列在筛网上,n个筛网依次按物料流动方向网孔降序排列,所述n个筛网的比例根据进入的物料筛透率E确定,所述n为进入筛网物料的粒度n个分级数。本发明通过将筛网分为多级不同网孔,使不合格的机制砂快速被筛出来,提高加工效率和产品质量。(The invention provides a method for adjusting fineness modulus of a machine-made sand composite screen; the screening device comprises n screening areas, wherein the n screening areas are sequentially arranged on a screen, the n screens are sequentially arranged in a descending order according to meshes in the material flowing direction, the proportion of the n screens is determined according to the material screening penetration rate E, and n is n grading numbers of the particle size of materials entering the screen. The screen mesh is divided into a plurality of stages of different mesh holes, so that unqualified machine-made sand is rapidly screened out, and the processing efficiency and the product quality are improved.)

1. The method for adjusting the fineness modulus of the machine-made sand composite screen is characterized by comprising the following steps of: the screening device comprises n screening areas, wherein the n screening areas are sequentially arranged on a screen, the n screens are sequentially arranged in a descending order according to meshes in the material flowing direction, the proportion of the n screening areas is determined according to the material screening penetration rate E, and n is n grading numbers of the particle size of the material entering the screen.

2. The machine-made sand composite screen fineness modulus adjusting method of claim 1, characterized in that: the screen penetration rate E is calculated in a mode of E ═ Q2/(Q1 multiplied by alpha) multiplied by 100%;

e-sieve penetration rate;

Q1-Total volume of material entering the shaker;

Q2-Total volume of material passing through the screen surface;

alpha is the material proportion coefficient smaller than the size of the sieve pore in the material entering the vibrating sieve; .

3. The machine-made sand composite screen fineness modulus adjusting method of claim 2, characterized in that: the alpha is the average value of the volume ratio of the screened material to the material entering the screen after a plurality of screening tests.

4. The machine-made sand composite screen fineness modulus adjusting method of claim 1, characterized in that: the proportion of the n screens is the proportion of the total volume of the n grading numbers of the materials.

5. The machine-made sand composite screen fineness modulus adjusting method of claim 2, characterized in that: the proportion of the total volume among the n grading numbers is based on the average value of the volume ratio of the materials which are sieved after a plurality of sieving tests to the materials which enter the sieve.

Technical Field

The invention relates to a method for adjusting fineness modulus of a machine-made sand composite screen.

Background

In the machine-made sand production process technology, raw material stones are coarsely crushed, medium crushed and finely crushed to obtain finished materials, the grading of the crushed sand is different due to different structures, strengths and the like of various raw materials, however, if the grading of the machine-made sand for concrete is not reasonable, the construction performance of the concrete is affected, and the mixing cost of a cementing material and the like needs to be increased.

According to the mechanism sand crushing principle and the actual situation, the smaller the particle size, the more difficult the crushing, therefore, the mechanism sand is mainly coarse particles with higher proportion and less fine particles, and the mechanism sand with coarse particles needs to be screened out quickly for processing again.

The theory of operation of shale shaker is that the material is at the sieve and the in-process that moves upward, throw the material again repeatedly through the shale shaker amplitude and fall back on the sifter, at this in-process, small granule material can sink the bottom and the screen cloth contact of special material stream and compare, when material footpath is less than screen cloth mesh size, when just handling the sieve mesh position, will pass the sifter and be screened out, and current shale shaker sifter mesh size is unanimous, when getting into the screen cloth originally, great granule shines the rate low, leads to its screening efficiency to hang down.

Disclosure of Invention

In order to solve the technical problem, the invention provides a method for adjusting the fineness modulus of a machine-made sand composite screen.

The invention is realized by the following technical scheme.

The invention provides a method for adjusting fineness modulus of a machine-made sand composite screen; the screening device comprises n screening areas, wherein the n screening areas are sequentially arranged on a screen, the n screens are sequentially arranged in a descending order according to meshes in the material flowing direction, the proportion of the n screens is determined according to the material screening penetration rate E, and n is n grading numbers of the particle size of materials entering the screen.

The screening efficiency of the vibrating screen is related to the processing capacity of the screen, the processing capacity per screen surface and the proportion of materials smaller than the size of the screen holes. The screening efficiency is gradually reduced according to the unit screen surface and the increase of the treatment capacity. The screening efficiency is reduced by increasing the proportion of material smaller than the size of the screen holes. Therefore, the screening areas with different apertures are controlled, and the proportion of each gradation of the control sand is controlled by changing the treatment capacity of the unit area, thereby adjusting the fineness modulus.

The screening penetration rate E is calculated in a mode of E ═ Q2/× 100%;

e-sieve penetration rate;

Q1-Total volume of material entering the shaker;

Q2-Total volume of material passing through the screen surface;

alpha is the material proportion coefficient smaller than the size of the sieve pore in the material entering the vibrating sieve; .

The alpha is the average value of the volume ratio of the screened material to the material entering the screen after a plurality of screening tests.

The proportion of the n screens is the proportion of the total volume of the n grading numbers of the materials.

The proportion of the total volume among the n grading numbers is based on the average value of the volume ratio of the materials which are sieved after a plurality of sieving tests to the materials which enter the sieve.

The invention has the beneficial effects that: through dividing into the screen cloth multistage different mesh, make unqualified mechanism sand by the sieve out fast, improve machining efficiency and product quality.

Drawings

Fig. 1 is a schematic structural view of the present invention.

Detailed Description

The technical solution of the present invention is further described below, but the scope of the claimed invention is not limited to the described.

A method for adjusting fineness modulus of a machine-made sand composite screen; the screening device comprises n screening areas, wherein the n screening areas are sequentially arranged on a screen, the n screens are sequentially arranged in a descending order according to meshes in the material flowing direction, the proportion of the n screens is determined according to the material screening penetration rate E, and n is n grading numbers of the particle size of materials entering the screen.

The calculation mode of the sieve penetration rate E is that E is Q2/Q1 multiplied by alpha 100 percent;

e-sieve penetration rate;

Q1-Total volume of material entering the shaker;

Q2-Total volume of material passing through the screen surface;

alpha is the material proportion coefficient smaller than the size of the sieve pore in the material entering the vibrating sieve; .

The alpha is the average value of the volume ratio of the screened material to the material entering the screen after a plurality of screening tests.

The proportion of the n screens is the proportion of the total volume of the n grading numbers of the materials.

The proportion of the total volume among the n grading numbers is based on the average value of the volume ratio of the materials which are sieved after a plurality of sieving tests to the materials which enter the sieve.

Example (b):

as shown in fig. 1, the same screening surface is divided into zones 1, 2, 3 and 3. According to the proportion of different materials in the materials, the area 1 is 6X 6mm, the area 2 is 4.5X 4.5mm, the area 3 is 3X 3mm, the area 4 is 2.5X 2.5mm, the area of the screen is 1: 3: 3: 1.

when the materials enter the vibrating screen, the materials with larger particle sizes are firstly screened off in the first screening area 4, so that the materials with smaller particle sizes in the second screening area 1, the third screening area 2 and the fourth screening area 3 are prevented from being influenced by blocking smaller meshes of the screen due to larger particle sizes and irregular shapes, and the other principles are the same;

the 1/3 that the areas of the first screen area 4 and the fourth screen area 3 at the two ends are reduced to the second screen area 1 and the third screen area 2 prevents larger and smaller materials from falling too much to influence the subsequent processing quality, and the purpose of the screen is to process the machine-made sand after separating coarse-granularity machine-made sand and small-granularity machine-made sand and improve the quality of the machine-made sand.