The production cost of sand aggregate is high and difficult to control. Maybe you haven't done that yet.Date: 2019-06-27 Views:
With the development of the construction of the infrastructure and the requirements of the environmental protection policy, the replacement of the natural sandstone with the artificial sandstone aggregate has become a big trend. And the quality of the artificial sandstone aggregate can directly influence the quality of the concrete and further influence the construction quality, so the quality of the sand and stone aggregate is very important.
1. Control the quality of material source
Before mining wool, it is necessary to remove the top overburden of the material yard, to ensure that there is no grass root, covering soil and other materials on the surface of the mining layer. When cleaning the overburden, it is necessary to set aside a certain width of the protective area, so as to avoid the vibration produced in the mining of wool to make the overburden at the boundary position slide and mix it into the wool again. In view of the fact that the buried degree of mudstone is different and the groundwater level is high, it is necessary to excavate the drainage canal and reduce the groundwater level before exploitation, and the mining should be carried out according to the order from low to high. For the overburden, the width of the peeling boundary is more than 0.8m larger than that of the planned mining area. For The depth of mining should be strictly controlled to ensure that the thickness of the reserved layer is more than 0.2 m.
2. Control particle size
The production of artificial sandstone aggregate is divided into the links of crushing, screening, sand making and the like, wherein the screening link is the key to controlling the particle size of the aggregate. The quality control of the sand and stone aggregate is mainly based on the particle size and grading requirements of the concrete aggregate, and adopts the advanced and mature crushing equipment and the screen of the vibrating screen and the standard pore size so as to ensure that the produced concrete aggregate meets the grading quality standard and requirements of the specification.
The screen for screening coarse aggregate can adopt polyurethane material square mesh screen, and the mesh size is divided into 5mm, 10mm, 20mm, 40mm, 80mm and other specifications according to the aggregate grading. Except for inspection at any time during the production process, centralized maintenance and replacement shall be conducted every month or every 20,000 m³ of production to ensure the integrity of the production equipment;In water conservancy and hydropower project, the general grading of coarse aggregate is divided into small stone(5~20mm), medium stone(20~40mm)and large stone(40~80mm);In hydropower projects, multilayer circular vibrating screen is widely used for screening and classification. The quantity is small, and the roller screen can be used for individual production according to the requirement. The screen of each sieve shall be inspected and replaced regularly, and the maintenance and replacement records shall be established, and the particle size of the sand and stone aggregate can be effectively controlled through the improved management means and scientific working procedures.
3. Control mud content
The inclination angle of the screen and the amount of raw material to be screened are strictly controlled and a reliable and stable flushing system is provided for the screen. the water supply capacity of the flushing system is 100-120m/ h, and the diameter is 100mm; the diameter of the water pipe used on the screening machine is 60 mm; the distance of the water supply pipe is controlled between 25 and 35 mm; the diameter of the water supply branch pipe used on the water supply pipe is between 5 and 8 mm, and the arrangement of the water spraying holes is uniform, The water pressure should be adjusted to the proper pressure at the time of flushing; the water sprayed from the adjacent water-spraying holes must cross so as to ensure that the sprayed water can cover the whole screen uniformly, otherwise, it is necessary to The arrangement quantity, interval and outlet direction of the nozzle are adjusted in time.
4. Protect the finished aggregate.
When the sand and stone aggregate screened from the screening workshop is transported through the belt conveyor to the finished material yard for storage, the wall should be set up for it to be stacked in a zone to prevent mixing in the yard. The product sign should be set up in the stacking place of the finished product, and the aggregate spacing without partition should be more than 3 m, and it should be orderly and orderly. The blind ditch drainage system is constructed in the finished product yard to ensure that the washed aggregate can be dehydrated quickly after entering the pile and meet the water content requirements used in concrete production.
For the production of natural sand aggregate, the production process of artificial sand aggregate is tedious, and the technical and professional requirements are very high. If there is any omission in the production process, it will have an impact on the quality of finished aggregate, and the cost of the whole production will rise in a straight line. Therefore, it is necessary to strictly control the production process, pay attention to the production process management, strictly monitor the whole production process, and ensure the high efficiency and orderly development of concrete sand aggregate production.