Advantages and Status Quo of Equipment in Concrete Mixing Station Industry in China
As China's urbanization process continues to advance, ready-mixed concrete has been rapidly developed and promoted in large and medium-sized cities across the country, and concrete mixing stations have also achieved rapid development. At present, there are many production enterprises in concrete mixing plants in China, and the products have been serialized, but the technical level is uneven. Only some products are close to the international advanced level. Some technologies have exceeded the level of imported concrete mixing plants, some of which have high automation and production. High capacity, high weighing accuracy, low investment, good mixing quality, can achieve multi-warehouse number, multi-mix ratio, continuous production continuously and high degree of localization of mainframe and its main components, but China's concrete mixing plant There are also shortcomings such as low overall technology content, low penetration rate, large regional differences, low intelligence and low environmental performance.
Advantages of concrete mixing plant in China: 1. High reliability The concrete mixing plant equipment has been developed in China for more than ten years. The development process is to introduce - digest - part of domestic - all domestic - improvement. It is normal for a concrete company to continuously produce 10,000 cubic meters of concrete. The performance of key components such as main engine, screw machine, main control and pneumatic components is quite stable. For example, the mixing blades are made of unique high chromium and high manganese alloy. The material, shaft end support and seal form use a unique multiple seal or airtightness to greatly improve the reliability of the mainframe. For the impact and easy wear, such as the discharge hopper, the transition bucket, etc., the wear-resistant steel plate is strengthened in the inner part; the ring-shaped belt joint is vulcanized and bonded, and the service life is increased by 3 times than the ordinary steel riveting, which is to ensure its reliability. Prerequisites for high sexuality.
2, the degree of automation control is higher After 2002, many concrete companies began to use two-way host multi-parallel way, to solve the increase in production capacity while ensuring a standby and reducing the waiting time of concrete transport vehicles. Most of its control systems are relatively advanced and stable, and the degree of automation is generally high. Both of them can be fully automated and continuously produced continuously for a long time. The operating platform and computer monitoring in the control room can visually reflect the entire production process and the situation of each part, such as cement storage of cement silos, aggregate storage in aggregate silos, aggregate transportation and concrete discharge, etc. In the case, once a problem occurs in a certain part, it can be found in the shortest time and solved in time.
3. All mixing stations are controlled by industrial computer, which can be controlled automatically or manually, and the operation is simple and convenient. The dynamic panel displays the operation of each part of the mixing station. At the same time, it can store various data of the mixing station, print various report materials according to requirements, and the storage formula can reach tens of thousands. The control room is equipped with air conditioning to ensure the durability of the electrical components, stable and reliable performance. The control system basically adopts two modes. One is the dual-machine dual control mode, that is, the system is composed of two high-performance industrial computers, one is used as the main control. The production system, another backup machine that serves as the main control production machine as the management and monitoring system, has the manual and automatic functions as the main control system, and the data sharing between the control machine and the management machine. When the control machine fails, it can be transferred to the management machine. Work to maximize the continuous operation of the system. The other is composed of an industrial computer plus batching control instrument, that is, the batching control instrument data is input into the industrial computer, and the execution signal is output through the board or the PLC programmable controller, thereby ensuring the system continues to operate normally. A surveillance camera can be set up in key components such as the main unit discharge port and the batching station.
4. High production capacity The emergence of double parallel stations and multiple parallel stations has greatly improved the production capacity of major concrete companies. For example, two 120 parallel stations can increase the annual output of concrete to 600,000 cubic meters, and three parallel stations. It can be raised to about 800,000 cubic meters, which fundamentally solves the problem that the lack of production capacity restricts the further development of most companies.
5. High measurement accuracy The measurement accuracy of concrete mixing station is divided into four aspects, namely aggregate, cement, water and admixture. The accuracy of aggregate is generally controlled within ±2%, and the precision of cement is generally controlled at ±1%. Within the water, the accuracy of the water is generally controlled within ±1%, and the accuracy of the admixture is generally controlled within ±1%. The measurement of aggregate is generally carried out by belt weighing and weighing hopper. The belt is called cumulative weighing, and the weighing hopper is individually weighed or accumulated. The weighing of cement and powder is generally carried out using a weighing hopper. When there are multiple powders, the weighing is used or weighed separately. The metering of water generally has two methods: volumetric type and weighing type. The volumetric type is divided into time metering method, quantitative meter metering method and turbine flow meter metering method; weighing type is divided into self-falling drainage weighing device and pressure water pump. Drainage weighing device and integral weighing barrel structure; the weighing of the admixture is volumetric, mass and pulse meter.
6. Whether it is the weighing of aggregate, powder or liquid, its weighing, control and signal conversion components are all imported components, high-precision sensors, imported microcomputer control, individual weighing or cumulative weighing, completely Ensure accurate measurement and stable performance.
Investing in the provincial concrete company's investment in the mixing plant is less than other pumping equipment. If the investment of one station 120 station is better than the configuration, it will not exceed 2 million yuan, and the two 120 parallel stations can also be controlled at about 3.6 million yuan.
Stirring quality is good. When the mixing machine is working, the transmission mechanism drives the two mixing shafts to rotate synchronously. Each mixing shaft is arranged with 4 to 8 stirring arms and two pairs of side stirring arms, which are equipped with stirring blades and scrapers. After the mixer, the mixing of the coarse and coarse aggregates, the blending agent, etc. by the stirring blade and the scraping plate causes the mixture to move radially and axially in the middle of the tank body, forming convection in the intersection between the two stirring shafts, thereby realizing strong material. Stir, so that the mixing quality is better and more uniform.
The twin-shaft forced mixer has strong mixing ability, uniform mixing quality and high productivity, and has good mixing effect on dry hard, semi-dry, plastic and various proportions of concrete. The lubrication system and the spindle drive system are all imported from a full set, and the hydraulic door opening mechanism can adjust the opening degree of the discharge door as needed. The mixing machine mixing shaft adopts anti-blocking technology to effectively prevent cement from agglomerating on the shaft. The shaft end seal adopts a unique multiple sealing structure to effectively prevent mortar leakage and ensure the long-term operation of the entire mixing system. The cleaning system adopts high-pressure water pump automatic control plus manual control. Each water outlet hole is located directly above the stirring spindle to improve the mixing efficiency, increase water mist, reduce dust pollution, and effectively remove cement agglomeration.
The localization of the mainframe and its main components is high. In recent years, many mixing plant manufacturers in China have developed multiple brands of hosts by absorbing foreign host technology, such as Siemens mainframe with Italian technology, Shigaoma host, Germany. The host of BHS technology has solved the situation that China's current mixing host has been plagued by quality defects for many years and has not been solved. In terms of major components, electrical and hydraulic components manufactured by Sino-foreign joint ventures or wholly foreign-owned enterprises, such as Toledo, Schneider, Siemens and Omron, are relatively stable, resulting in a significant reduction in the cost of domestic stations. And stability is no less than the imported mixing station.