One. Raw material quality management. Hot asphalt mixture is made up of three parts: aggregate, powder and asphalt. The management of raw materials mainly involves how to ensure the quality and safety of raw materials in all aspects of storage, transportation, loading and unloading and inspection. 1.1 management and sampling of asphalt material, quality management of 1.1.1 asphalt material (1) the quality certificate and inspection sheet of the original plant should be attached to the asphalt material when entering the mixing station. (2) the laboratory should check whether every batch of asphalt should be sampled to meet the requirements of the national standard. (3) after the test room sampling inspection is qualified, the material department should issue the acceptance list, record the source, mark, quantity, date of arrival, invoice number, place of storage, quality of inspection and the location of asphalt used. (4) every batch of bitumen should be kept for inspection of material not less than 4kg after inspection. 1.1.2 sampling of bituminous materials (1) sampling of bituminous materials shall ensure the representativeness of the material. The asphalt tank shall have a dedicated sampling valve and shall not be sampled from the top of the asphalt tank. Before sampling, 1.5 liters of asphalt should be released to remove pollutants from valves and pipes. (2) the sampling container should be clean and dry. Sticker on the container. The storage, transportation and management of 1.2 aggregates (1) should be stacked in a hard and clean site. The site should have good waterproof and drainage facilities, the fine aggregate is covered with shading cloth, and the aggregates of different specifications are separated by the partition wall. When the bulldozer is heaped, it should be noted that the thickness of each layer should not exceed 1.2m thickness. When the bulldozer is stacked, the disturbance of the aggregate should be as small as possible, and the material heap should not be pushed into the groove on the same plane. (2) every batch of materials should be sampled and analyzed in accordance with national standards on the specifications, gradation, mud content, and needle sheet content. It is proved that the material can be stacked in the rear and issued the acceptance list. The indexes of the quality inspection of the aggregate should be in accordance with the specifications and the requirements of the owners' documents, and should be checked regularly during the construction process. The gradation characteristic of the material pile is changed.
Two, the construction of aggregate, mineral powder and asphalt feeding system.
(1) the loader's hand should be loaded on the side of the material pile without coarse material rolling. In the loading, the bucket should be inserted into the bucket with the arm of the pile to make the bucket up to the top, and then back, do not dig with the method of rotating the bucket, which can reduce the segregation of the material. (2) for the parts that have already been clearly separated, the parts should be remixed and then reloaded; the loader hand should keep the warehouse full of the cold storage and prevent the mixing in the loading. (3) the flow of cold materials should be checked regularly to avoid intermittent feeding and gushing. (4) the speed of feeding belt should be maintained at medium speed when calibrating productivity, and the speed range should not exceed 20 to 80% of the maximum speed. (5). The mineral powder should be prevented from moisture absorption. The compressed air used for the broken arch should be used by water separation. The powder in the mineral powder conveying device should be emptied after the end of the project. (6) before mixing the equipment, the heat conduction oil furnace should be started to heat up the asphalt in the asphalt tank to the specified temperature, and to preheat all parts of the asphalt feeding system. When the asphalt pump is started, the oil valve should be shut down to make the empty turn start, then slowly open the oil intake valve and gradually add the load. The asphalt pump should be reversed for a few minutes at the end of the work so that the asphalt in the pipeline can be pumped back into the asphalt tank.
Three, the construction of the drying heating system
(1) at the beginning of the work, the drying drum should be started by manual control when the cold material supply system stops, and the small fire preheating barrel of the burner can be ignited after 5 to 10min, and the feeding amount should be gradually increased when the material is on the material, and the amount of oil supply will be gradually increased according to the hot material temperature of the outlet, so as to reach the specified production and stable temperature. After the working condition, it will be transferred to the automatic control mode. (2) when the cold material system suddenly stops feeding or other accidents, the burner should be shut down and the roller will continue to rotate, the fan will continue to pump the air, and then the cylinder will be shut down after the body is completely cooled. At the end of the work, the shutdown should be done in the same way. (4) check whether the infrared thermometer is clean, wipe off the dust and keep good sensing ability. (5) when the water content of the cold material is high, the automatic control system will be out of control and the temperature oscillates up and down. At this time, manual control should be used, and the residual water content of the hot material should be checked, such as the production quantity should be reduced too high. (6) the residual moisture content of hot aggregate should be checked regularly, especially in rainy days, and the residual water content should be controlled below 0.1%. (7) the temperature of the exhaust gas should not be too high or too low. The general control is about 135~180 degrees centigrade, such as the high temperature of the exhaust gas, and the increase of the aggregate temperature, mostly due to the large water content of the cold material, and the production should be reduced in time. (8) the pressure difference between the inside and outside of the bag filter should be kept within a certain range. The pressure difference is too large to indicate that the bag has been seriously blocked. It is necessary to deal with and replace the cloth bag in time.
Four. The construction of hot material sieving storage system (1) should often check whether the hot material screening system is overloaded, whether the screen is blocked or there is a hole, if the material on the screen is too high, it should be stopped to adjust. (2) the mixing rate of the 2 hot storage bin should be regularly sampled and the mixing rate should not exceed 10%. (3) when the material supply of the hot material system is unbalanced and the flow of the cold bin needs to be changed, the supply of a silo should not be increased suddenly, otherwise the aggregate gradation will be seriously affected.
Five, the construction of measurement control and mixing system (1) the weighing data of each batch of mixed material recorded by computer is a powerful means to check the normal work of the metering control system. After starting the machine every day, the weighing data should be printed for 2 hours after the work is stable, and the system error and random error are analyzed. If it is found to exceed the requirement, it should check the system work in time, analyze the reasons and eliminate it. (2) the mixing system should not stop during mixing. When mixing equipment should wait for the truck to stop working, the mixture in the mixing cylinder should be emptied. (3) every day after the end of the mixing cylinder work after the use of hot ore to scrub, to remove the residual asphalt in the agitator, usually with coarse aggregate, fine aggregate 1~2 times. (4) when the hoisting hopper is used to unload the mixture into the finished silo, the hopper must be located in the central discharge of the silo, otherwise the longitudinal segregation will appear in the barrel, that is, the coarse material will roll to the side of the silo. (5) when the scraper conveyor is used to unload the mixture into the batching bucket and then be unloaded into the finished material silo, a part of the mixture should be preserved in order to avoid the segregation of the mixture transported by the scraper directly into the silo after the material is completely empty. (6) when unloading from the finished silo to the truck, the truck is not allowed to unload on the side of the truck and should be dumped, otherwise it will cause serious segregation, and the truck driver is not allowed to add a small amount of mixture on the material heap for the rated capacity. (7) when discharging from the finished warehouse, the discharge door should be opened quickly, and it is not allowed to let the mixture flow out slowly, so as to avoid segregation. (8) when discharging to the truck, it is not allowed to discharge to the center of the car trough. It should be discharged to the front of the groove and then discharged to the rear end, and then discharged in the center.